CONTACTS & CONTOURSPRESENTED BY: RABIA ALI C-11 BATCH D

Topics to be discussed Normal physiologic tooth contours Hazards of faulty reproduction ofphysio anatomical features of teeth in restoration Variations in shapes of teeth Procedures for proper formulation of contacts and contours

Physiologic toot contours:contours: All teeth possessphysiologic contours which permit proper stimulation & provide protection for their investing & supporting tissues. Characteristic variations in the location of general height of contours are: A. In gingival third area of all ANTERIOR TEETH.

B. In gingival third area of MAXILLARY POSTERIOR Teeth. Most prominent on lingual

C. In GINGIVAL THIRD area most prominent on buccal surfaces & middle third area on lingual surfaces of mandibular posterior teeth. Most prominent on buccal.

Cervical ridge:ridge:If the cervical convexity of a crown and the normal tissue relationship are lost, the height of convexity of a restoration must re-establish the original physiologic relationship of the crown contours to the free gingiva and to the gingival attachment.

A. properrelationship of crown contours B. Insufficient crown contour C. Excessive crown contour

Embrasure relationship:relationship:GINGIVAL EMBRASURE Anterior teeth:teeth:A.Gingival embrasures wider and deeper than incisal embrasures. B. Lingual embrasures wider and deeper than labial embrasuresLINGUAL EMBRASURE

A INCISAL EMBRASURE LABIAL EMBRASURE

Posterior teeth:teeth:GINGIVAL EMBRASURE

C. Gingival

embrasures wider and deeper than occlusal embrasures.BUCCAL EMBRASURE

D. lingual

embrasures wider and deeper than buccal embrasures

LINGUAL EMBRASURE

Marginal ridge relationship:relationship:-

Correct

incorrect

Essential for:Balance of teeth in arch Prevention of food impaction proximally Protection of periodontium Prevention of recurrent & contact decay Helping in efficient mastication

Contact areas:areas:Contact relationships of posterior teeth. A. Point or marble-like contact areas present at time of eruption. B. Broad flat contact area resulting from excessive wear. C. Typical contact areas resulting from the usual amount of wear observed in a patient of middle age.

A A

Contact areas in Maxillary teeth:teeth:anterior:anterior:-

CENTRAL

CENTRAL

LATERAL

Contact and embrasure relationships of maxillary central incisors labial view.

LATERAL CUSPID FIRST BICUSPID Contact and embrasure relationship of lateralincisors and cuspids labial view.

Cuspids & first bicuspid:bicuspid:-

Contact and embrasure relationships of maxillary cuspids and first bicuspid teeth - buccal view.

Incisal view

Contact and embrasure relationships of maxillary cuspids and maxillary posterior teeth - occlusal view.

First & second bicuspid & first molar teeth:teeth:-

FIRST BICUSPID

SECOND BICUSPID

FIRST MOLAR

Contact and embrasure relationships of the first and second bicuspids and first molar teeth - buccal view.

occlusal view

First, second & third molar teeth:

FIRST MOLAR

SECOND MOLAR

THIRD MOLAR

Contact and embrasure relationships between the first, second, and third molar teeth - buccal view.

occlusal view.

Mandibular teeth: Incisors & cuspids:

Contact and embrasure relationships between the mandibular incisors and cuspid teeth - incisal view

CENTRAL CENTRAL , LATERAL CUSPID labial view.

Cuspid & first bicuspid:bicuspid:-

LATERAL CUSPID BICUSPID BlCUSPlD Contact and embrasure relationshipsbetween the mandibular cuspids and first bicuspid teeth - buccal view.occlusal view.

First & second bicuspids & first molar teeth:

FIRST BlCUSPlD

SECOND FIRST MOLAR BICUSPID

Contact and embrasure relotionships between mandibular first and second bicuspids and first molar teeth - buccal view.

occlusal view.

First, second & third molar teeth

Second bicuspid

First molar

Second molar

Third molar

Contact & embrasure relationships between mandibular first second and third molar teeth - buccal view.

Occlusal view

Hazards of faulty reproduction of Physio-anatomical features of Physioteeth in restorations:restorations:A. Contact size:size: Broad contact

Narrow contact

Contact too occlusally

A. Too bucally

B. Lingually

C. Gingivally

Loose (open) contact

Contact configuration:configuration:-

C. Contour:Contour: Faial and lingual convexities Facial and lingual concavities Areas of proximal contour adjacent tocontact area

Facial and lingual convexities

Facial & lingual concavities

Areas of proximal contour adjacent to contact area

a. Absence of a marginal ridge in therestoration.

c. Marginal ridges:ridges:-

b. a marginal ridge with an exaggeratedocclusal embrasure:embrasure:-

c. Adjacent marginal ridges notcompatible in height:height:-

d. A marginal ridge with no adjacenttriangular fossa

e. A marginal ridge with no occlusalembrasure:embrasure:-

f. A one-planed marginal ridge in the onebuccolingual direction:direction:-

g. A thin marginal ridge in its mesiodistal bulk:bulk:-

h. Marginal ridge not compatible indimension or location with the rest of the occluding surface components:components:-

Variations in shapes of teeth:teeth:Tapering Square/box Ovoid/ barrel

y

contact

tapering

square

Ovoid

1.Between incisors

Contact starts at the incisal ridge incisaly & a little towards the labial, labiolabio-lingualy

Start at incisal ridge incisally & in line with it labiolabiolingually

1.Slightly lingual to incisal ridge labiolabio-lingually 2.Mesial contacts start at of the crown incisogingivally. 3.Distal contacts start 1/3 to of the crown incisoincisogingivally

contact

tapering1.Mesal contact at incisal ridge 2.Distal contact near the middle 3.Very angular

square1.Close to incisal ridges incisally 2.In line with them labiolabiolingually

ovoidThe same as square type

2.canine

3.bicuspids

1.Buccal periphery almost at buccal axial angle(buccal 3rd) of tooth. 2.Occlusal periphery at junction of occlusal & middle 3rd. 3.Contact deviated bucally 4.Cusps form -1/3 of crown

1.Buccal periphery more towards buccal axial angle 2.Occlusal periphery at occlusal 3rd. 3.Short cusps.

Convexity of MR carries occlsal periphery towards middle 3rd.2.buccal periphery at junction of buccal and middle third.

contact

tapering.

Square

Ovoid

4.Molars mesial contact 5.Molarsdis tal contact

1.Buccal periphery almost at the buccal axial angle of tooth. 2.o2.o-periphery at junction of occlusal and middle third of crown 3.Large cusps 1.B1.B-periphery at middle 3rd. 2.O2.O-periphery at middle third 3.Distal contact of 1st molar is variable due to position of distal cusps

1.The same as premolar 2.Extention lingually stops in middle 3rd.

Same as bicuspids.

More lingually deviated than the mesial but to the extent of tapering teeth.

B-periphery in line with central groove in o-surface. o-

contact

tapering

Square

Ovoid

embrasures

1.Wide variations 2.Incisal and labial are negligible 3.Gingival and lingual between anterior teeth are widest and longest in mouth 4.buccal are small 5.Lingual are long, with medium width. 6.Gingival between posterior teeth are broad and long

1.incisal,lingual,occlusal and buccal embrasures are nil 2.Gingival almost not noticeable; if found, v.narrow and flat. 3.Lingual are v.narrow (may be slit) and long.

1.incisal,labial,buccal and occlusal are wider and deeper than the others 2.Gingival and lingual are short and broad.

PROCEDURE FOR FORMULATION OF PROPER CONTACTS AND CONTOURS

Intra oral procedures Extra oral procedures

Intra oral procedures:procedures:1. Tooth movement

2. Matricing

Tooth movement:movement:The act of either separating the involved teeth from each other, bringing them closer to each other, and/or changing their spatial position in one or more dimensions.

OBJECTIVES:OBJECTIVES: To bring drifted tilted or rotated teeth totheir indicated physiological position for proper reproduction of proximal surfaces in restorative materials. To close space between teeth not amenable to closure by the contemplated restoration. To move teeth to a position most physiologically acceptable by periodontium. Extrusion or intrusion of teeth making them restorable.

Moving teeth from a nonfunctional or

traumatically functional position to a physiologically functional one. Moving teeth to an aesthetically pleasing position To increase dimensions of available tooth structure for resistance and retention forms of restoration. Creating sufficient space for matrix band interproximaly Easy access to proximal surface for cavity preparation Detection of proximal caries Facilitate polishing of restorations proximal surface Remove foreign bodies impacted proximally

Methods of tooth movement Rapid or immediate

Slow or delayed

Rapid or immediate Mechanical type ofseparation that creates either proximal separation at the point of separators introduction and/or improved closeness of proximal surface opposite the point of separators introduction

Indications:Indications: Preparatory to slow tooth movement Maintain space gained by slow toothmovement

Methods:Methods:1.Wedge method 2.Traction method

Wedge method:method:Separation accomplished by insertion of a pointed wedge shaped device between the teeth, in order to create separation at that point or closure on the opposite proximal side of involved teeth. a. Elliot Separator b. Wooden or plastic wedges

Functions of wedges Assure close adaptibility of the matrix and to thetooth

Occupy the space designated to be the

gingival embrasure Define gingival extent of contact area, facial & lingual embrasures Create space to compensate matrix band Temporary hemostasis Immobilization of matrix band Protect interproximal gingiva from unexpected trauma

consequences of poor wedge techniqueAmalgam condensation requires high packing forces if it is going to be adequate. These forces will always push amalgam beyond the matrix unless it is wedged, causing overhangs. Overhangs will often result in periodontal disease(+ bone loss),and caries.

Accidents can happen both when a practitioneris inexperienced, and when (over-) confident of (overtheir skills.

The wedge in this radiograph had encroachedtowards the contact area, leaving a poor contour. This results in food packing and plaque accumulation.

Wooden wedges Resin wedges. C. Nail of thumb or first finger:finger: For instantaneous use e.g planning theaxial wall, forming line angles, polishing of class III restoration

Traction method:method:mechanical devices, engage in proximal surfaces of teeth to be separated by means of holding arms. a. Non-interfering true Nonseparator:separator:Provides continuous stabilized separation during operation Separation can be increased or decreased

B. Ferrierdouble bow separator:separator: Separation stabilized throughout operation Separation shared by contacting teeth & not at the expense of one tooth

Slow or delayed tooth movement Over a period of weeks will allow proper repositioning of teeth in a physiologic manner Methods:Methods:separating wires Over sized temporaries Orthodontic appliances