Fill in the space:EMBRYOLOGY

1- The ....................... begins by fertilization of the ovum till the development of three germ layers 2- The ............................ extends from the beginning of the third week of intra-uterine life (3rd wiu) to the end of the 8th wiu. 3- The ........................... is considered as the first trimester of pregnancy, so any maternal illness are well known to cause congenital deformities.

4- The fetal period extends from the end of the 8th wiu,...................... 5- During the ...............l period there is a rapid increase in the overall size of the fetus. 6- The nervous system begins to develop at the ............. intra uterine life.

7- During the development of nervous system, certain group of nervous system cells forms a unique population of cells known as the .......................

8- All the tooth structures are derived from neural crest cells except .................9-The stomodeum is separated from the blind end of the foregut by the ..............................

10-.............................. formed by double layers of epithelium, ectoderm of the stomodeum and endoderm of the foregut.

11- At ....................intra uterine life the buccopharyngeal membrane soon breakdown and the stomodeum communicates with the foregut.

12-From the roof of the stomodeum, .......................... develops and forms the anlage of the anterior lobe of the pituitary glands.

13- At the 4th week intra uterine life, the anterior portion of the foregut gives six pairs of outgrowths called the ........................

14- The mandibular arch send out a prominence called .................... at its proximal end before extension, while its distal extension is called .......................

15-The branchial arches are covered by ................... from out side and lined by ................... from inside except the first arch. 16- The cartilage bar of the first arch is called ................... and has a role in the development of the mandible.

17- The remnant of the anterior portion of Meckel's cartilage gives the .....................

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18-The remnant of middle part of Meckel's cartilage gives the .................of the mandible.19- The............................. ligament originates from the fibrous coverage around the Meckel's cartilage.20- The remnant of posterior portion of ..................... gives the incus and the malleus of the middle ear.21- The muscles of mastication are drived from the ..........................., while the muscles of facial expression are drived from the ..................22- Each branchial arch is supplied by blood vessels originating from the ..................23-The first arch is supplied by the................................................ arteries, while the ................ arch is supplied by the facial artery.24- The................. arch is supplied by the internal and common carotid arteries.25- The sensory nerve that enters the corresponding arch and divide inside the arch is called...........................26-The sensory nerves gets from the nerve of the preceding arch is called ...........................as its division occurs before entering the arch). 27-The first arch is supplied by the.....................nerve as a posttrematic nerve and supplied by the ...................... which is the branch of the second branchial arch, facial nerve as post trematic nerve.

28-The................arch is supplied by the glossopharyngeal nerve, while the other preceding arches are supplied by the ............... nerve.

29- The branchial arches are separated by external shallow depression called ........................

30- The branchial arches are separated from the pharyngeal side by deep depression called ..........................31-The ......................... is involved in the formation of the external auditory meatus, tympanic membrane, tympanic cavity of the middle ear and Eustachian tube. 32-The second pharyngeal pouch deepens to give rise to the.........................and capsule.33-development of the face starts at ................wiu.34-The lower lip developed by the median fusion of the two .........................prominences.

35- At the 5th wiu, the frontonasal process develops two bilateral oval shaped ectodermal thickening named ...........................

36-During the development of face, the horseshoe shaped outgrowth encircling the nasal placodes has lateral and medial edges called ................................

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37- The lateral and medial nasal processes convert the nasal placode into depression called......................

38-The lateral nasal processes of both sides are separated from the maxillary processes by a groove named ................................

39- The lateral nasal process gives rise to the ...............................

40-The mouth orifice is determined by the degree of fusion between the ........................and ...........................processes of both sides.

41-The primitive lip and cheeks are invaded by the mesenchymal tissues of the ...............branchial arch which give rise to the muscles of facial expression.

42- The .......................... is due to failure of union of the mandibular processes at the midline. 43-The maxillary cleft lip results from failure in the proper union of the .............................. with the...........................

44- Macrostomia occurs as a result of lack of union between the ................. and .................... processes.45- Transverse facial cleft is the other name of ......................46-Microstomia results from .................. of the maxillary and mandibular processes, leading to very small mouth.47-.......................... resulting from lack of fusion between the medial and lateral nasal processes with maxillary processes.

48- During development of the secondary palate, the maxillary prominences from both sides give new outgrowths from their medial edges called the ..........................49- During fusion of palatal shelves, the surface epithelial cells are sloughed off as they undergo............................ to expose the basal epithelial cells.50-................... is result of lack of union of both palatine processes with each other and with the nasal septum.

51- Vestibular lamina gives rise to ..............................52- The tongue develops from two separate parts which later on fused together in V shape line called.............................53- The anterior 2/3 of the tongue is known as ................... portion of the tongue while the posterior 1/3 of the tongue is named .................... portion of the tongue.

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54-The persistence of the tuberculum impare during tongue development leads to appearance of reddish rhomboid structure known as ......................................... 55-The epiglottis originates from the ..................................as it is supplied by superior laryngeal nerve which is a branch of the vagus nerve

56- The foramen ceacum represents the opening of a ..........................

57- The circumvallate and foliate papillae are supplied by the ................................. nerve for taste sensation.

58- The posterior portion of the posterior 1/3 of the tongue and the epiglottis are supplied by the ............................ (nerve of the 4th arch) for general sensation.

59-The ................nerve supplies the intrinsic and extrinsic muscles of the tongue.60-The extrinsic muscles of the tongue are developed from the...................... migrating on the hypoglossal nerve.

61- The final tongue papilla developed is the..........................papillae.62- The circumvallate and foliate papillae are the first papillae appears near to the termination of........................................nerve.63-The........................ papillae appear near to the termination of the chorda tympani branch of the facial nerve.64- The first sign in the development of fungiform, circumvallate and foliate papillae is the appearance of ........................65-The ..............................papillae are localized at the tip and border of the anterior 2/3 of the tongue.

66-When the alveololingual groove fails to separate the tip of the tongue from

the floor of the mouth this condition is known as...................

67-The ........................ is the 1st gland develops at 6 wiu at the angle of the stomodium between the mandibular and maxillary prominences of both sides.

68-The mandible develops in the lower part of the first branchial arch by ...........................ossification.

69- The development of the mandible starts by the appearance of ossification center at the bifurcation of the ................. and........................ nerves.

70- The secondary cartilages centers in the developing mandible are .............., ............... and..........................cartilages

71- The ...................cartilage appears at 14 wiu and continues till the age of 20 years of life.

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72- The ...................r cartilage gives rise to the condylar head and neck of the mandible and the posterior part of the ramus as low at the mandibular foramen.

73-The.................cartilage appears at 4 miu and disappears before birth at 6 miu.74- The.....................cartilage gives rise to the the coronoid process and the anterior part of the ramus to a point as low as the mandibular foramen.75-The.................... cartilage appears after the coronoid cartilage formation and disappears at the end of the first year of life. 76-The..................... cartilages give rise to the symphysis of the mandible 77- The most important secondary cartilage for the growth of the mandible is .....................cartilage. 78- Maxilla proper develops by the appearance of 1st center of the intramembranous ossification at the bifurcation of the ...............................nerve and the .............................79-Development of maxillary sinus starts at .......................as a small depression of the mucosa of the lateral wall of the nasal cavity.80-Growth of the..................... depends mainly on secondary cartilage.81-Growth of the ..................... depends mainly on their bony sutures.82- The sutural growth of the maxilla continues till ................... of age then become less significant.83- The ................. suture lies between the frontal process of the maxilla and the frontal bone.84- The .................... suture lies between the maxilla and the zygomatic bone.85-The ..................... suture lies between the temporal process of zygomatic bone and the tempral bone.86-The ................ suture lies between the pterygoid process of the sphenoid bone and the pyramidal process of the palatine bone. 87-The growth at the maxillary sutures allows shift the maxilla .................and ....................88-The enlargement of the maxillary sinus by bone resorption on the sinus side and bone deposition on the facial surface of maxillary process is known as .................................

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Key answers

EMBRYOLOGY

1- proliferation period 2- embryonic period 3- embryonic period

4- until birth. 5- fetal 6- third week

7- neural crest cells

8- enamel. 9- buccopharyngeal membrane.

10- buccopharyngeal membrane

11- 4th week

12- Rathke's pouch

13- branchial arches

14- maxillary process / mandibular process

15- ectoderm/ endoderm 16- Meckel's cartilage17- mental ossicles18- lingula 19- spheno-mandibular 20- Meckel's cartilage 21- mandibular arch22- aortic arch 23- external and internal carotid/ second 24- third 25- post-trematic nerve26- pre-trematic nerve 27- mandibular / chorda tympani

28- third / vagus

29- branchial clefts

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30- pharyngeal pouches 31- first branchial cleft 32- tonsillar fossa 33- 4th 34- mandibular

35- nasal placodes

36- lateral and medial nasal processes

37- nasal pit

38- nasolacrimal groove

39- ala of the nose

40- maxillary/ mandibular

41- second

42- mandibular cleft lip

43- medial nasal process/ maxillary process

44- maxillary/ mandibular45- Macrostomia46- over fusion 47-Oblique facial cleft

48- palatine processes49- apoptotic cell death 50-Cleft palate

51- oral vestibule52- sulcus terminals53- papillary/ lymphoid54- median rhomboid glossitis 55- 4th branchial arch

56- thyroglossal duct

57- glossopharyngeal

58- internal laryngeal nerve

59- hypoglossal 60- occipital myotomes

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61- filiform 62- glossopharyngeal 63- fungiform 64- taste buds65- fungiform

66- tongue tie

67- parotid gland

68- intramembranous

69- mental/ incisive

70- condylar, coronoid and symphysial

71- condylar

72- condylar

73- coronoid 74- coronoid 75- symphysial 76- symphysial 77- condylar 78- anterior superior dental / infra-orbital nerve 79- 4 miu 80- mandible 81- maxilla 82- 10 years 83- fronto-maxillary 84- zygomatico-maxillary 85- Zygomatico-temporal 86- pterygo-palatine 87- forward/ downward88- pneumatization

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TOOTH DEVELOPMENT

1-Odontogenesis of the primary dentition begins at ................. wiu life.2- The first stage of tooth development known as the .......................3- The vestibular lamina located ................ to the dental lamina.

4- An........................... is the space between the maxilla and the mandible on one side and the lips and the checks on the other side 5-The second stage of odontogensis is called the ..................

6-The ectomesenchymal cells condensation just beneath the enamel organ is called ..........................

7- The connective tissue-beneath-and around the enamel organ and dental papilla forming what is called ....................................

8- A .............................. remains between the bud and the growing underlying ectomesenchyme.

9-The tooth primordium has three components ........................, ................... and dental sac 10-The dental organ is..................... in origin, while both dental papilla and dental sac are .......................... in origin.11-The .......................proposes that ectomesenchyme assumes the dominant role in crown pattern formation. 12- The ...........................proposes that epithelium assumes the dominant role in crown pattern formation. 13-The third stage of odontogenesis is called the .....................

14- The stellate reticulum cells synthesize and secrete ................................

15-The lingual extension of the dental lamina is called the .......................................

16-The ..............................are non succedaneous and have no primary predecessors.

17-The permanent molars develop from a ...........................of the dental lamina.

18-The fourth stage of odontogensis is called the .............................

19-In the bell stage, the connection of dental organ to the dental lamina is elongated forming a .....................................

20-The point at which inner enamel epithelium differentiation first occurs represents the site of future ...........................................

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21-The region where the inner and outer enamel epithelia meet at the rim of the enamel organ is known as..................................

22-The stellate reticulum layer is most fully developed at the .........................23- The cells of stratum intermedium contain much ............................. enzyme which essential for enamel maturation.

24- The remnants of the dental lamina and the lateral dental lamina are called ..............................

25-After the crown of the tooth is formed, the dental papilla is called ...........................26-The peripheral cells of the dental papilla will differentiate into ...............whereas the inner cells are the primordium of the .....................

27-The final stage of odontogensis is known as ............................

28- The ...........................seen during the early stages of tooth development are enamel knot, enamel cord and enamel niche.29- A layer of cells that seems to be essential to enamel formation but does not actually secrete the enamel is ......................................30-The .......................... is a strand of cells extending form the stratum intermedium into the outer enamel epithelium.

31-The process of root development takes place after the .................. is completely formed.

32-The....................... is the structure responsible for root development.

33-The function of ...................... is to map out the root and induce dentin formation in the root area.

34- The remnants of epithelial root sheath of Hertwig are called .....................................35- The number of roots that are formed is determined by the number of ..........................................

36-............................... is the union of the root structure of two or more teeth through the cementum only.37- Concrescence commonly occurs in ....................................

38- Misplaced enamel formed on the cemental root surface is called ..........................39- ...................................... is distortion in root (or roots) or crown angulations in a formed tooth.

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40- ........................is a deviation or bends restricted just to the root portion of the tooth and less than 90 degrees. 41- Supernumerary roots occurs mainly in the ..........................42- The stimulus that initiates the actual formation of enamel matrix seems to be the presence of .........................43- The lateral dental lamina gives rise to .............................44- The epithelial rests in the periodontal ligament are derived from ..................................45- The last hard dental tissue to be deposited is ............................46- The epithelial root sheath of Hertwig disintegrates .................. odontoblastic differentiation & dentin matrix deposition.47- The dental lamina is induced to proliferate into a tooth bud by the ................................48- The .......................... lies between inner enamel epithelium & stellate reticulum.49- The epithelial component of the tooth germ is known as ....................................

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Key answers

TOOTH DEVELOPMENT

1- sixth2- initiation stage3- buccal

4- oral vestibule 5- bud stage

6- dental papilla

7- dental sac (follicle)

8- basement membrane

9- enamel organ, dental papilla 10- ectodermal / ectomesenchymal 11- field model 12- clone model 13- cap stage

14- glucosaminoglycans

15- successional dental lamina

16- permanent molars

17- posterior extension

18- bell stage

19- lateral dental lamina

20- incisal edge or cusp

21- cervical loop

22- bell stage 23- alkaline phosphatase

24- epithelial rests of Serre's

25- dental pulp26- odontoblasts / pulp

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27- apposition stage

28- transitory structures 29- stratum intermedium30- enamel cord

31- crown

32- cervical loop

33- root sheath

34- epithelial rests of Malassez 35- medial ingrowths at the epithelial diaphragm

36-Concrescence 37- permanent maxillary molars

38- enamel pearls 39- Dilaceration 40- Flexion 41- permanent third molars 42- predendtin43- deciduous teeth44- epithelial root sheath of Hertwig's45- cementum46- after 47- ecto-mesenchyme48- stratum intermedium 49- enamel organ

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Tooth Eruption

1- ......................begins in the early bell stage and ends at the beginning of root formation. 2- Increase in width of the jaws leads to movement of the germs ..............................3-Increase in height of jaws leads to the ....................... movement of the germs (Excentric growth).4-.................... growth means that one part of the developing tooth germ remains stationary and the remainder continues to grow leading to a shift in its center.5- In ...................... bone resorption occurs only on the crypt wall facing the growing tooth germ.

6- .................. begins by root formation and ends when the tooth reaches the occlusal plane.

7- In ....................... stage of eruption, the rate of eruption accelerates. Then it becomes very slow as it approaches the occlusal plane.

8- If there are prolonged delays in eruption, ...............of tooth to bone can result.9- Eruption of the maxillary third molar in the maxillary sinus represents an ...................eruption.

10- ...........................is a bluish, opaque asymptomatic swelling which overlays an erupting tooth due to the accumulation of blood or tissue fluid in the dilated follicular sac around the eruption crown.

11- Eruptive path is achieved by the ........................ canal which is filled with the ...................................12- In a dried skull, holes that identified in the jaws on the lingual aspects of the anterior deciduous teeth represents the opening of the ...............................

13- ......................phase begins after the tooth has reached its functional position in the occlusal plane and continues through the whole life of the tooth.

14- The occlusal wear is compensated by continued..................deposition.15-......................... is compensated by a process known as mesial drift.

16- ........................ theory supposes the existence of cushion- hammock ligament, running across the base of the socket from to provide a fixed base for the growing root to react against.17-............................... theory proposed that the cells and fibers of the periodontal ligament pull the tooth into occlusion.

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18-................................... supposes that a local increase in tissue fluid pressure in the periapical region is sufficient to move the tooth.

19-................ is a fusion of cementum or dentin to alveolar bone due to cellular changes in the periodontal ligament caused by trauma and other pathologies.

20- The ankylosed tooth appears.................... in relation to adjacent teeth that continue to erupt.

21- The ankylosis most commonly affects....................... and .......................22- Ankylosis can lead to:- .........................................- .............................................................- ................................................................

23- ................... is a cessation of eruption of a tooth.

24- The ......................are particularly prone to impaction because they erupt last when the least room is available. 25- The................................. also frequently is impacted because of its late eruption.

26-.......................... is eruption of a developing tooth beyond the range of the normal eruption path.

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Key answers

Tooth Eruption

1- Pre-eruptive phase 2- labially or buccally 3- occlusal 4-Eccentric 5- eccentric growth

6- Eruptive phase

7- extra-osseous

8- ankylosis 9- ectopic

10- Eruption hematoma

11- Gubernacular bony / Gubernacular cord 12- Gubernacular canal

13- Post eruptive

14- cementum 15-The interproximal wear

16- Root formation 17-Periodontal ligament traction

18-Vascular pressure theory

19-Ankylosis

20- submerged

21- Dentin and Enamel 22- Loss of arch length / Extrusion of teeth of the opposite arch / Interference with the eruption of succedaneous teeth.

23- Impaction

24- third molar25- upper canine

26-Ectopic eruption

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SHEDDING

1- .................. is the physiological elimination of the deciduous teeth.

2- The permanent incisors and canines develop................ to the deciduous teeth and erupt in an occlusal and vestibular direction.

3- The resorption of the roots of the ........................ often begins early on their inner surface facing the inter-radicular septum.

4- The premolar tooth germs move................... to the deciduous molars to relieve the pressure on the roots of the overlying deciduous molars.

5-The process of tooth resorption is ....................; there periods of resorption and periods of rest and repair.

6-The resorption of the hard dental tissues of deciduous teeth is achieved by highly specialized multinucleated cells called .........................

7-Odontoclasts are derived from ...................................

8-Odontoclasts are found on a shallow hollowed out depressions or bays called ...............................

9-.............................. are able to resorb all hard dental tissues including cementum, dentin and on occasions enamel.

10-The tooth sheds with some pulpal tissue intact except that ..................... seem to be missing.

11-the pulp plays a ...................... role in the shedding process.

12-Retained deciduous tooth are most often the..................................

13-The most frequently remnants are found in the region of .......................... because their roots are widely divergent.

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Key answers

SHEDDING

1- Shedding

2- lingual

3- deciduous molars

4- apical

5- intermittent

6- odontoclasts

7- blood circulating monocytes

8- Howship's lacunae

9-Odontoclasts

10- neural elements

11- passive

12- upper lateral incisor

13- premolars

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ENAMEL

1- Ameloblasts having ruffled borders are........................ ameloblasts.2- .................. ameloblasts are characterized by having a distal cell membrane with many infoldings.3-......................... are a result of variation in rhythmic apposition.4- Enamel.....................are grass like structure.5- Organic components of enamel are primarily removed from enamel by .........................6- Enamel is composed of rod,....................................7- The extensions from secretory ameloblast cells that give structure to enamel rods are called ...............................8- ...........................s are due to rhythmic apposition of enamel. 9- ................. is formed of 96% minerals & 4% organic materials and water.10- In enamel ...................... appear to be periodic bands at 4 microns interval across the rod.11- The complex arrangement of rods over the cusps of teeth is termed .............................12- Prismless enamel is ...................mineralized than prismatic enamel.13- The predominant inorganic portion of enamel is .........................14- Developmental enamel lamellae is type............. enamel lamellae.15- The predominant organic portion of mature Enamel is...............................16-.........................makes up the outside layer of anatomical crown of a tooth.17- The ............... lines fissures, grooves and pits.

18- The property that enables enamel to withstand the mechanical forces applied during tooth functioning is ............................19- Enamel has a certain degree of .................. The main pathway is from saliva to the outer layer of enamel.

20- Mature enamel is composed of 88-90 % inorganic material and 10-12 % organic material and water by .......................

21- Fluoro-apatite is 20% less soluble than ..................... which means that it is much less susceptible to demineralization.22- Because ........................help killing cavity-causing bacteria. So, it used as topical application on the teeth to minimize caries.23- 90% of the developing enamel proteins is a heterogeneous group of low-molecular weight hydrophobic proteins known as.........................24- ........................secreted by differentiating ameloblasts.25- ...................... interdigitate with the surface of the forming enamel giving it a picket fence appearance.

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26- ...................... determine the orientation of hydroxyapatite crystals and so responsible for the rod structure of enamel

27- ....................... is a brief reorganization stage between enamel secretion and maturation.28- During .......................stage there is selective withdrawal of enamel proteins, mainly amelogenin, and water.29 - The maturative ameloblasts are either ..........................ended (80 % of maturation ameloblasts) or ..................ended (20 %). 30- In the .....................ended ameloblasts the distal junctions are leaky and the proximal are tight. 31- The .............................protects the enamel from being in contact with connective tissue cells in the dental sac. 32- The reduced dental epithelium and the oral epithelium are joined to form the .................................of the erupting tooth.33- Human enamel forms at a rate of ......................... per day.

34- differentiating ameloblasts release small isolated drops of unmineralized enamel proteins called ................................

35- .....................................is characterized by gradual completion of mineralization to reach the 96 % of the total weight of enamel.36- During the maturation process,..................... and ameloblastins are removed leaving ..................... and tuftelin in the mature enamel. 37- Histological structure of................. could be described in ground sections only.38- Under the cusp tip and incisal ridges, the course of the rods is more complicated where they become twisted and braided together and it is called .........................

39-....................... are an optical phenomenon, viewed by oblique reflected light.

40- ...........................overlying the cusps and incisal edges do not reach the surface unless there is some enamel loss due to attrition. 41- ...................... mainly appears in deciduous teeth and first permanent molars and may be associated with increased caries susceptibility .42- The quality of the ................enamel is better than that of the ................ enamel due to the more protected condition and constant nutrition.43- ..................... results from some odontoblastic processes, during the early stages of enamel formation, pushed themselves between the pre-ameloblasts.44- Enamel .................. are most common beneath cusps where most crowding of odontoblasts would have occurred.

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45- Enamel lamellae are............................... or unmineralized and narrower, longer and less common than enamel tufts.

46- ..................... lamellae are hypo mineralized. They never extend to dentin.They would contain more enamel proteins and less crystals than the rest of enamel.47-......................... is a crack occurs in the enamel before the tooth eruption due to a stimulus on the enamel surface causing its fracture. 48- .................... is a crack occurs in the enamel after the tooth eruption while it is functioning in the oral cavity.

49-The convexities of the scallops of the DEJ are directed towards the ......................50- Rodless enamel occurs as a result of the absence of ....................... on the ameloblasts in the final stage of enamel formation.

51- Perikymata is numerous near the .................... and nearly disappear at the ...........................region. 52- Rod-end markings are shallowest in the ....................... and deepest near the ............................surfaces.53- ...................cementum occurs in 60 % of cases.54- ................is the physiological wearing away of the tooth hard substance as a result of tooth to tooth contact .

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Key answersENAMEL

1- maturative2- Maturative 3-Incremental lines4- tufts 5- maturative ameloblasts6- interrod & rod sheath7- Tomes processes8- Striae of Retzius 9- Enamel 10- cross striations 11- Gnarled enamel12- more 13- calcium14- A 15- enamelin16-Enamel 17- enamel

18- hardness19- permeability

20- volume

21- hydroxyapatite 22- fluoride ions 23- amelogenins 24-Stippled material 25-Tomes' processes 26- Tomes' processes

27- Transitional stage 28- maturative 29 - ruffled/ smooth30- smooth31- reduced dental epithelium 32- dento-gingival junction 33- 2.5-6 microns

34- stippled material.

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35- Secondary maturation 36- amelogenins / enamelins 37- enamel 38- gnarled enamel

39-Hunter-Schreger bands

40- Brown striae of Retzius 41- Neonatal line 42- prenatal / post natal 43-Enamel spindle44- spindles

45- hypomineralized

46- Developmental 47-Type B lamella 48- Type C lamella

49- dentine 50- Tomes, processes

51- cervical region / incisal or cusp 52- cervical region / occlusal and incisal 53- Afibrillar 54- Attrition

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Dentinogenesis & Dentin Structures

1- .................. is the mineralized tissue that forms the bulk of the tooth.

2-Two major properties distinguish dentin from enamel: First, dentin is .......... Second, dentin ...................................

3- Dentin is slightly harder than...............or ............... and is less hard than ................... 4- On radiographs, dentin appears more .................. than enamel and more ..................... (lighter) than pulp. 6- The collagen of dentin comprises over 90% of the organic matrix. The principle collagen fibril is type ..................., traces of type III and type V collagen are also found. 7-........................... are highly specialized connective tissue cells that differentiate from the peripheral cellular layer of the dental papilla.8- Secretory odontoblasts exhibit ...................... and ..................... activity along their plasma membranes. 9- The................. odontoblast produces dentin in a very slow rate.

10- In resting odontoblasts, there are increase in number and size of ............... and

........................

11- The Mantle dentin varying in width from ................ µm. The large collagen fibrils (0.1-0.2 mm in diameter) aggregate in the cell free zone. 12- The collagen fibrils of mantle dentin are aligned ...................... to the basal lamina, while in the mantle dentin of the root they are......................

13- ..................................theory proposes that fluid movement through the tubules distorts the local pulpal environment and is sensed by the free nerve endings in the plexus of Raschkow. 14- The ...................dentin is the basic structure of dentin and forms its bulk. 15- The collagen fibers of ......................... dentin are smaller in diameter (0.05Mm) and are more closely packed and interwoven with each other.16- The fibers of circumpulpal dentin are present ............................. to the tubules.17- The ground substances of the ....................... dentin are exclusively a product of odontoblasts.

18- The vesicles that bud from the odontoblast cells during mineralization of dentin are called ..............................

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19- .............................theory supposes that dentin contains nerve endings, which respond when dentin is stimulated.

20- The function of .......................... is to provide a special micro-environment in which the first hydroxyappatite crystals can form.

21- the presence of matrix vesicles is limited to........................ dentin.22- ....................... calcification founds in mantle dentin.23-................................. calcification usually presents in circumpulpal dentin formed just below mantle dentin.24- In the rest of the circumpulpal dentin, a combined pattern of calcification occurs with a ........................phase alternating with a .................... phase. 25- The convexity of the primary curvatures of dentinal tubules nearest the pulp chamber faces..........................26- The ............................. result from the spiral track taken by the odontoblast during its course from the outer dentin surface to the pulp.

27- In some places of the crown, the peripheral ends of some odontoblastic processes cross the dentino-enamel junction and protrude into the enamel, forming ...............................

28- Dentin located between the dentinal tubules is called ......................................

29- ...................................dentin is type of highly calcified dentin matrix deposited on the internal surface of the walls of the dentinal tubules narrowing the size of the lumen.

30- .......................... dentin contains little amount of collagen. It is about 40% more mineralized than intertubular dentin.

31- External stimulus accelerates ..........................r dentin formation that eventually may obliterate the tubules spaces.

32- ......................... dentin will be seen as translucent rings in ground sections.

33-....................................... is the area of unmineralized or hypomineralized dentin where globular zones of mineralization have failed to fuse within mature dentin.

34- Inter-globular dentin is seen most frequently in the ........................ dentin just below the.................... dentin.

35- ................................. is a constant feature of the root dentin immediately adjacent

to cementum.

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36- .....................................do not follow any incremental pattern and usually smaller

than interglobular dentin.

37-...............................do not cross through Tomes' granular layer.

38- Incremental lines of Von-Ebner run at right angles to..................................

39- ........................................... may results from a coincidence of the secondary curvatures between neighboring dentinal tubules.

40- ............................. could be seen in all deciduous teeth as well as in the mesio lingual cusp of the first permanent molar.41- .................................... dentin develops by odontoblasts after root formation has been completed.

42- The reparative dentin with no tubules at all named ............................While that with trapped forming cells named .................................

43- ............................. is characterized by calcification of dentinal tubules, where the odontoblastic processes undergo fatty degeneration and then calcification.

44- ......................... dentin appears translucent when viewed by transmitted light while with reflected light these areas appear dark.45- Dentin areas characterized by degenerated odontoblastic processes have been called ......................................

46- Each ...................... is surrounded and isolated by a narrow zone of sclerotic dentin.

47- ..........................may be caused in some teeth by the death of odontoblasts crowded in narrow pulpal horns.

48- ..................................... theory contends that a dental stimulus excites the odontoblastic process which then transmits the excitation to the adjacent nerve plexus.

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Key answersDentinogenesis & Dentin Structures

1- Dentin

2- sensitive/ is formed throughout life.

3- bone / cementum / enamel. 4- radiolucent / radio-opaque 6- I collagen 7-The odontoblasts 8- alkaline-phosphatase / Ca-ATPase 9- resting

10- lysosomes / phagosomes.

11- 20-150 12- at right angles / parallel to it.

13- Fluid or hydrodynamic 14- circumpulpal 15- circumpulpal 16- at right or oblique angles 17- circumpulpal

18- "matrix vesicles"

19- Direct neural stimulation

20- matrix vesicles

21- mantle 22-Linear 23-Globular (calcospherite) 24- globular / linear 25- root ward26- "secondary curvatures"

27- "Enamel spindles".

28- "inter-tubular dentin"

29- Peri-tubular "intratubular"

30- Intratubular

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31- peritubular

32- Peritubular

33-Inter-globular dentin

34- circumpulpal / mantle

35- Tomes' granular layer

36- Tomes' granular layer

37-The dentinal tubules

38- the dentinal tubules

39- Contour line of Owen

40- Neonatal line 41-Regular secondary

42- "atubular dentin"/ "osteodentin"

43- Sclerotic dentin

44- Sclerotic 45- "dead tracts"

46- dead tract

47-Dead tracts

48- Odontoblastic transduction

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Cementum Structure and Cementogenesis

1-......................... comprises matrix formation and mineralization of cementum.2- The ............................ will induce the neighboring cells of the dental papilla to differentiate into odontoblasts.3-The epithelial root sheath of Hertwig will loss its continuity and its cells become ............................................4- The cells entrapped in the mineralized cementum are referred to as ................................and occupy lacunae.

5- cellular cementum has a ................. mineral content than acellular cementum.

6- The Sharpey's fibers of .......................cementum generally retain an unmineralized core.

7- The Sharpey's fibers of ........................ cementum exhibit a complete degree of mineralization.

8- Sharpey's fibers are derived from ..........................., which are not calcifiable in their original location.

9- Although the .......................is laid down throughout life, the mineral content of this tissue, once formed, does not change significantly with age.

10- .................................. covers minor areas of the enamel, particularly at and along the cementoenamel junction. 11- ........................... is unique in that it is avascular, does not undergo continuous remodeling like bone, but continues to grow in thickness throughout life. 12- ............................... has significant function in tooth anchorage to the surrounding bone through numerous Sharpey’s fibers inserting into it13- The ........................ can repair a resorptive defect of the root in a reasonable time due to its capacity to grow much faster than any other known cementum type.14- The thickness of cementum at the cervical area is about ............................and gradually increases in thickness till it reaches its maximum about ......................... at the apex and at the bifurcation of the root.

15- .........................contains 45% to 50% inorganic substances and 55% to 50% organic materials.

16- Under the light microscope two types of cementum can be differentiated: .................. and...............................

17- The cementum is usually covered by a zone of ....................... 3-4 microns wide in acellular cementum and is wider in cellular cementum.

18-.......................... covers the root dentin starting from the amelo-cemental junction till the apex, but it is often missing at the apical third of the

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19- ........................ have processes directed toward the periodontal surface of the cementum to provide nutrition.

20- It appears that the number of cells that become incorporated in cementum is proportional to the...........................................

21- In cementum, the .............................................are highly mineralized areas with less collagen and more ground substance. 22-The incremental lines of Salter are roughly .............. to the long axis of the root.23- The cellular cementum is formed at .................... rate than the acellular cementum and the incremental lines are therefore located further apart than in acellular cementum.24- In ................. of all teeth, cementum meets the cervical end of enamel in a relatively sharp line.25- In about ..................of the teeth cementum overlaps the cervical end of enamel for a short distance. 26- Over compression of the periodontal ligament can result in the...................... of cementum and dentin.

27- Cementum is markedly ................ on the distal than on the mesial root surface, indicating a relationship to mesial drift.

28- .................... is an abnormal thickening of cementum.

29-............................... is increase of cementum in good function teeth to permit more periodontal fibers to be attached to the tooth.

30- Increase of cementum in a non-functioning tooth or in an embedded tooth, this is called ......................................

31- Cementum hyperplasia is characterized by the......................... of Sharpey’s fibers.

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Key answersCementum Structure and Cementogenesis

1-Cementogenesis 2- inner dental epithelium 3- the epithelial rests of Malassez. 4- cementocytes

5- lower

6- cellular

7- acellular

8- periodontal fibers

9- cementum

10-Acellular afibrillar cementum 11- Cementum 12-Acellular extrinsic fiber cementum 13- CIFC 14- 20-50 microns / [150-200u]

15-Cementum

16- the acellular/ the cellular cementum.

17- cementoid tissue

18-Acellular cementum

19-Cementocytes

20- rate of cementum deposition.

21- incremental Lines of Salter 22- parallel 23- a faster 24- 30%25- 60% 26- resorption

27- thicker

28-Hypercementosis

29-Cementum hypertrophy 30- cementum hyperplasia. 31- absence

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Periodontal ligament

1- The periodontal ligament is ............. that occupies the periodontal space between the root of the tooth and the alveolus

2- The width of PDL ranges from 0.15-0.38 mm, with the narrowest width at the ................. and its widest width at the...................... followed by the apical region.

3- The PDL is formed from the ...................... shortly after root development begins.

4- As the tooth erupts, the level of the alveolar crest comes to coincide with the .........................and the oblique fiber bundles below the gingival fibers become horizontally aligned.

5- When the tooth finally comes into occlusion, the horizontally aligned fibers, termed..........................., become obliquely oriented.

6- The intercellular substances of PDL comprise ..............................

7- The connective tissue fibers are mainly collagenous. The main types of collagen in the PDL are types.....and ........

8- PDL fibers are divided into:

................................ ................................ ................................

9- Alveolo-dental fibers are subdivided into the following five groups:- ..............................-................................- .............................-................................- ..................................10- The trans-septal fibers group are located just ......................... on the mesial and distal sides of the tooth only. The bundles of these fibers run from the ......................over ...........................and inserted into the comparable region of the .....................................

11- The alveolar crest group resists the....................movements of the tooth.

12- The horizontal group resists the ............................ applied to the tooth crown.

13- The oblique group running from the cementum in an ................ direction to be inserted into the bone .............. This group prevents the apex of the root from

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being .............. against the bottom of the socket during..............pressure applied to the tooth crown.

14- The apical group resist any force tending to .............. the tooth from the socket .

15- The inter-radicular group functions in.................. the tooth.

16- The accessory fibers run from bone to cementum in ....................., more tangentially to................... of the tooth and found in the region of the .................group.17- The oxytalan fibers constitute no more than............of the PDL fibers. They are attached into the ...................of the tooth and course out into the PDL in various directions. 18- Oxytalan fibers may have a role in ..................... It also supports the blood vessels of the PDL during .................... and prevents the ................ of them under masticatory forces.

19- Cells of the PDL include: - .....................................- .........................................- ............................................- ................................................- .................................................20- The epithelial rests of Malassez may proliferate to form ..........if stimulated.

21- The space between the cells, fibers, blood vessels and nerves in the PDL is occupied by ................ It is made up of two major groups of substances, ................. and ..............................

22- The blood vessels of the PDL are branches of the ............ or ............ artery and vein, and they enter the PDL from various directions:- .....................................................-......................................................- ....................................................23- Periodontal nerve fibers are both myelinated and unmyelinated. The myelinated fibers are...............fibers only.

24- In human beings the small nerve fibers of PDL are responsible for ................ , while the large diameter nerve fibers terminate in specialized endings known as .................. , responsible for ............................................

25- In PDL there are four types of nerve endings :

-...............................

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-...............................

- ............................

-.................................

26- The PDL through aging shows decreases in.....................and decreases in the ..................... It become .............. in thickness and may contain ...................

27- The cementicles in the PDL may be ....... , ............ or ................... in the cementum, and are formed of ......................... of the periodontal tissue.

28- Functions of PDL are:- ...........................- .........................- .......................- .........................

- ............................

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KEY

Periodontal ligament

1- the dense fibrous connective tissue

2- middle third of the root

3- dental follicle

4- cementoenamel junction

5- alveolar crest group,

6- fibers and ground substances

7- I / III

8- The principal fibers / The accessory fibers / The oxytalan fibers.

9- Alveolar crest group / Horizontal group / Oblique group / Apical group / Inter-radicular group10- apical to the gingival group / cementum of one tooth / the alveolar crest / cementum of the adjacent tooth.

11- horizontal

12- horizontal pressure

13- oblique / coronally. / jammed / vertical

14- lift

15- stabilizing

16- different planes / prevent rotation / horizontal

17- 3% / cementum

18- tooth support / mastication / sudden closure

19- Synthetic cells: (fibroblasts, osteoblasts and cementoblasts) / Resorptive cells: (cementoclasts, osteoclasts and fibroclasts) / Progenitor cells: (undifferentiated mesenchymal cells) / Defensive cells: (macrophage, lymphocytes and mast cells) / Epithelial cells: (epithelial rests of Malassez). 20- cysts or tumors

21- ground substance / proteoglycans /glycoproteins.

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22- superior / inferior alveolar / Branches from the apical vessels that supply the dental pulp / Branches from the intra-alveolar vessels / Branches from the gingival vessels.23- sensory

24- pain sensation / mechanoreceptors / localization of touch and pressure on the teeth.

25- free nerve endings / Ruffini's corpuscles / coiled form / spindle-like ending.

26- vascularity / number of its cells / thinner / cementicles.

27- free / attached / embedded / dystrophic calcification.

28- Supportive / Sensory / Nutritive / Formative / Protective.

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Bone structure

1- The two major components of bone are.............. and....................

2- Bone cells consist of ......................... , ....................... ,.......................... and

..........................

3- The osteoblasts shape is generally ........................cells that line bone surfaces and are primarily responsible for the production of ....................................

4- The organic matrix produced by osteoblasts consists predominantly of type...............collagen and various other…………..................... and.............................

5- When bone is no longer forming, osteoblasts flatten extending along the bone surface, and are termed ................................

6- The space in the matrix occupied by an osteocyte is called the ..........................

7- osteoclasts are found against the bone surface, occupying hollowed-out depressions called .................................... that they created.

8- The cytoplasm of the clear zone or sealing zone is enriched in ........... , ............ and .......................

9- Organic matrix is formed from a scaffold of interwoven .........................within and between which small, uniform, plate-like crystals of .......................... are deposited.

10- The lamellar bone makes up the ......................

11- Between the outer and inner circumferential lamellae are several groups of concentric lamellae surrounding a central canal: the .........................

12- The units of circumferential lamellae are 5-20 lamellae arranged concentrically around a central canal of 20-300 u diameter that contains .......................... , .............., connective tissue, and lined with ....................................

13- Spongy bone consists of ......................... with many intervening ....................... which give the maximum rigidity to the bone itself.

14- The periosteum is attached to the bone at the circumferential lamellae by coarse connective tissue fibers called the.................................

15- Periosteum acts as a medium for................................ , and it performs a nutritive function to the underlying bone.

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KEY

Bone structure

1- cells and matrix components.

2- osteoprogenitor cells / osteoblasts / bone-lining cells and osteocytes.

3- cuboidal / the organic matrix of bone.

4- type I collagen / mucopolysaccharides / plasma proteins.

5- bone lining cells.

6- osteocytic lacunae.

7- Howship’s lacunae.

8- actin / vinculin / talin.

9- collagen fibers / carbonated hydroxyapatite.

10- skeleton

11- Haversian canal

12- blood vessels / nerves / osteoprogenitor cells.

13- bone trabeculae / bone marrow spaces.

14- Sharpey's fibers.

15- attachment of the muscles and tendons

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THE TEMPROMANDIBULAR JOINT

1- The development of the joint starts at..........

2- The condylar blastema grows rapidly in a ............ direction to close the gap.

3- Ossification begins first in the....................

4- The Temporomandibular joint is a ........................ articulation between the mandible and the.............................

5- The joint cavity is divided into an upper ................ compartment and a lower compartment by a ...........................

6- The joint cavity is filled with...................fluid formed by ........................

7- The condyle is the ................ surface of the mandible; it is about 15-20 mm long and 8-12 mm thick.

8- Both the ........................and the ........................ comprise the cranial articulation of the TMJ.

9- The disk is ................ of uneven thickness, ranging from 2 mm anteriorly, to 3 mm posteriorly and 1 mm in the middle.

10- The hyaline cartilage in the condyle serves as an active growth center till the age of..........................

11- The articulating surface of temporal bone is covered by .................. fibrous tissue of type I collagen similar to that of the condyle.

12- The fibers within the intra-articular disk are principally composed of type ................collagen and comprise about 80 % (dry weight) of the disk.

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KEY

THE TEMPROMANDIBULAR JOINT

1- 3 M.I.U.

2- dorso-lateral.

3- temporal blastema.

4- bilateral synovial / temporal bone.

5- larger / fibrous disk.

6- synovial / synovial membrane.

7- articulating

8- Glenoid fossa / articular eminence.

9- biconcave

10- 20 years.

11- avascular

12- I

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Saliva & Salivary Glands

1- Salivary glands are .............., ............... glands whose ducts open in the oral cavity.

2- The serous cell are ......................... in shape arranged in ............... layer, their apices are situated towards the..................

3- Following the synthesis of secretory products, serous cell will contain numerous ..................... granules in the cytoplasm of the apical portion near to the lumen.

4- At later phase of secretory cycle, the mucous cell exhibits numerous round and isolated secretory granules called...............................

5- The nuclei of mucous cells are ................. and ......................... located.

6- Unlike serous cells, mucous cells lack intercellular canaliculi, except for those covered by ..........................

7- Myoepithelial cells contract as a result of activity of both .........................and ..............................stimulation.

8- Myoepithelial cell contains numerous contractile............. myofilaments 4-8 µm in diameter.

9- Myoepithelial cells contain contractile actin filaments, which can be identified using......................................

10- The cells of the striated duct exhibit small secretory granules on the luminal side containing ....................growth factor.

11- The excretory ducts are located in the connective tissue septa between...........................

12- Parasympathetic stimulation of the salivary gland results in secretion of ...................saliva and induces the contraction of the myoepithelial cells.

13- Sympathetic stimulation of the salivary gland results in the secretion of ...............................

14- The major salivary glands are .................organs enclosed in well developed ................

15- The parotid glands are flattened organs located under the skin of the face in front and below each ear filling the space between the ....................... and .................................

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16- The main duct of each parotid gland is................................ opens into the oral cavity on the buccal mucosa opposite the..................................tooth.

17- In the parotid of the adult human being, the spherical secretory end pieces are all ....................., while in new born and old age the gland is ............................................

18- The parotid gland contributes in...........................of saliva volume.

19- The parasympathetic nerve supply of the parotid gland is derived from the ninth ................................ reaching the gland through the ....................... ganglion and the ................................. nerve.

20- The sympathetic innervations of all the major salivary glands are provided by .........................fibers from the ...............................ganglion, and reach the individual glands in association with their vascular supply.

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KEY

Saliva & Salivary Glands

1- merocrine, exocrine.

2- pyramidal / one / lumen.

3- zymogen.

4- mucigen granules.

5- flattened and basally.

6- demilunes.

7- parasympathetic and sympathetic.

8- actin

9- immuno-cytochemistry

10- kallikrein.

11- the lobules of the gland.

12- watery

13- thick viscid fluid.

14- paired / capsule.

15- ascending ramus and sternomastoid muscle.

16- Stensen's duct, / second maxillary molar tooth.

17- serous, / mixed with few mucous portions.

18- 25-30%.

19- glossopharyngeal, / otic / auriculotemporal.

20- postganglionic / superior cervical.

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The Maxillary Sinus

1- The maxillary sinuses are the largest air containing spaces that occupy the .............bone ............................. in the body of the maxilla.

2- The maxillary sinus develops in the..............................of intra-uterine life.3- The maxillary sinus gradually expands by ......................... of the body of the maxilla, and reaches its full size and development when the permanent dentition is completed.

4- The capacity of the sinus varies from......................with an average of 15 ml.

5- Drainage of the maxillary sinus occurs through its opening :.............................

6- The maxillary sinus lining is formed of three layers: ........................ resting on a basement membrane,........................... and..............................

7- The maxillary sinus is composed of ............................................................., rich in ........................ which secrete mucous that moisten the surface of the sinus mucosa.

8- The goblet cell is a ......................... gland which pours its mucin secretion by rupturing the apical cell membrane which will again regenerate and known as ...........................

9- By Electron Microscope, the ciliated cell encloses a nucleus and an ........................cytoplasm with numerous ............................

10- The cilia are composed of........................of microtubules and they provide the .....................apparatus to the sinus epithelium.

11- The lamina propria of the sinus mucosa is fused with the ......................of the underlying bone and consists of loose bundles of collagenous fibers with very few ..............................

12- ..............................glands are present in the lamina propria.

13- The serous secretory product consists primarily of water with small amount of neutral nonspecific lipids, .......................... and .........................

14- The mucus secretion consisting of compound .......................... or ............................or both.

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KEY

The Maxillary Sinus

1- maxillary / bilaterally

2- third month.3- pneumatization

4- 9.5 to 20 ml.5- ostium maxillare.6- epithelial covering, lamina propria and periosteum.

7- pseudo-stratified columnar ciliated epithelium, rich in goblet cells

8- unicellular / apocrine gland.

9- electron-lucent / mitochondria.

10- (9+1) pairs / motile.

11- periodontium / elastic fibers.

12- Mixed

13- proteins and carbohydrates.

14- glycoproteins or mucopolysaccharides

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Oral Mucous Membrane

1- The oral epithelium is .................in origin and formed of ..............................

2- The keratinized epithelium is found in the areas of oral mucosa subjected directly to the ..............................of food during mastication. The epithelial cells that ultimately keratinize are called............................

3- The keratinocytes are arranged in .............layers: ................., .................., .............................and .............................. Each layer consists of several rows of cells except the ........................., which is formed of one row of........................................4- The basal cells and the spinous cells constitute more than ..................... the thickness of the epithelium.

5- The cells of the spinous layer are joined together by ........................... giving the cells a .......................appearance.

6- The spinous cells are the most active cells in ........................synthesis. The cells have a well-developed ........................, .............................and numerous mitochondria.

7- In the upper part of the stratum spinosum appear small, intracellular membrane-coating granules called ...................... that are rich in...............................

8- Odland bodies are approximately 0.25 μm in length and in keratinized epithelium consist of a series of.............................

9- The rate of epithelial renewal is ......................... in the lining more than in the masticatory mucosa.

10- The lamina propria is divided into 2 layers, superficial zone of loose connective tissue called the.......................... and a deeper zone of denser connective tissue called .............................

11- The papillary layer contains predominantly .............................. arranged as a loose open network. While in the reticular layer the collagen fibers are ........................... and closely packed.

12- The lamina lucida consists of glycoprotein called ...........................

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13- Fibronectin in the lamina densa play a role in .................................. and proteoglycans to it.

14- The basal lamina provides..............................between the oral epithelium and the lamina propria and plays a role in the response to tissue injury.

15- mucogingival junction is called also the.................................

16- Morphologically the gingiva is divided into.............................., .............................and the...................................

17- The depth of the gingival sulcus under normal conditions varies from zero to 6mm, with the average of ........................

18- Histologically the gingival stippling corresponds to .....................................elevating the epithelium.

19- The epithelial portion of the gingiva, which is in direct contact with the surface of the tooth, is called ............................ or.............................20- Coronally the junctional epithelium may be 15-30 cells thick, whilst apically it narrows to only 1-3 cells thick. It consists of two zones; a single cell layer of cuboidal cells called.............................., overlying several layers of flattened cells equivalent to a.....................

21- The basal lamina in contact with the tooth is termed ....................................

22- Each taste bud is composed of.........................cells, ............................... cells, and ..............................cells.

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KEY

Oral Mucous Membrane

1- ectodermal / stratified squamous epithelium.

2- mechanical irritating effect / keratinocytes.

3- four / stratum basal, stratum spinosum, stratum granulosum and stratum cornium. / basal layer, / cuboidal or columnar cells.4- half

5- intercellular bridges / prickly

6- protein / Golgi apparatus, rough endoplasmic reticulum

7- Odland bodies that are rich in phospholipids.

8- / parallel lamellae.

9- higher

10- the papillary layer / reticular layer.

11- fine collagen fibers / coarser

12- laminin.

13- adhering fibroblasts

14- mechanical adhesion

15- healthy line.

16- free gingiva, attached gingiva and the interdental papilla.

17- 1.8 mm.

18- high connective tissue papillae

19- attachment epithelium or junctional epithelium.20- the stratum germinativum, / stratum spinosum.

21- the internal basal lamina.

22- Outer supporting cells, Inner supporting cells, and Neuroepithelial cells.

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