1 Diagnosis of pd patients fayad

Diagnosis of partially edentulous patients

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EXAMINATION, DIAGNOSIS

AND TREATMENT PLANNING

Objectives of any prosthodontic treatment:

(1) The elimination of disease;

(2) The preservation, restoration, and maintenance of the health of the remaining teeth and oral tissues (which will enhance the removable partial denture design);

(3) The selected replacement of lost teeth for the purpose of restoration of function in a manner that ensures optimum stability and comfort in an esthetically pleasing manner.

Indications for a removable in preference to a fixed partial denture

A. Edentulous areas too long for a fixed prosthesis.

B. Need to restore soft and hard tissue contours.

C. Absence of adequate periodontal support.

D. Structurally or anatomically compromised abutment teeth.

1. Lack of clinical crown height.

2. Lack of sound tooth structure.

3. Unfavorable position, contour or inclination.

E. Need for cross-arch stabilization. F. Eed for an extension base.

G. Anterior esthetics.

H. Physical and emotional problems precluding fixed partial dentures.

1. Attitude and desires of patient.

J. Ease of plaque removal from the natural teeth and partial de ture.


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BASIC CRITERIA FOR PATIENT SELECTION

A. Acceptable emotional and physical health.

1. Basic health observations. 2. Complete health history.

B. General physical and mental capacity to tolerate a prosthesis.

1. Previous number of prostheses. 2. Physical handicaps.

C. Degree of patient motivation.

1. General personal appearance.

2. Past oral hygiene habits and response to sug¬gested change.

3. Patient's desire to preserve remaining teeth and surrounding structures.

4. Physical and mental capabilities to augment motivation.

5. Patient's response to scientific evidence.

D. Patient's comprehension of pote - tia success or failure of treat¬ment.

E. Types and amounts of drugs or med-ications the patient co sumes including alcohol and tobacco.

F. Patient's dietary habits.

G. Periodontal health.

H. Oral indices of tissue tolerance.

Indicate the capacity of supporting structures to resist mechanical forces.

1. Muco-osseous (ridge) resistance. Bone index of the residual ridge (reaction of bone after extraction and ridge loading),

2. Dento-alveolar (abutment) resistance. Bone index around the abutment teeth (reaction of bone to increased force).

3. Soft tissue resistance to biological or mechan¬ical irritation.

I. Oral manifestations of pathology.

J. Consultations with other medical and dental specialists.


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PURPOSE AND UNIQUENESS OF TREATMENT

The purpose of dental treatment is to respond to a patient's needs.Although there are similarities between partially edentulous patients, significant differences exist making each patient, and treatment, unique.

The delineation of each patient's uniqueness occurs through the patient interview and diagnostic clinical examination process. This includes fourdistinct processes:

(1) Understanding the patient's desires or chief concerns/complaints regarding their condition (including its history) through a systematic interview process.

(2) Ascertaining the patient's dental needs through a diagnostic clinical exam.

(3) Developing a treatment plan that reflects the best management of the desires and needs (unique to their medical condition or oral environment).

(4) Appropriately sequenced execution of the treatment with planned follow up.

Complex treatment planning often requires two appointments.

The first appointment includes

a preliminary oral examination (to determine the need for management of acute needs),

a prophylaxis,

full-mouth radiographs,

diagnostic casts, and

Mounting records if baseplates are not required.

The follow-up appointment includes

mounting of the diagnostic casts (when baseplates and occlusion rimsare needed),

a definitive oral evaluation,

review of the radiographs to augment and correlate with clinicalfindings,

arrangement of additional consultations where required,


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I- FIRST DIAGNOSTIC APPOINTMENT

A. Patient interview:

B. Cursory (initial) examination

C. Oral prophylaxis

D. Collecting diagnostic data: • Photography • Radiography • Casts

II-SECOND DIAGNOSTIC APPOINTMENT

A-Definitive oral examination:

B-Radiographic survey

C-Analysis of mounted diagnostic casts:

D. Consultation requests:

E. Development of treatment plane.

III-TREATMENT PLANE IN RPD

Prosthodontic Diagnostic Index ( PDI ): see classification

The American College of Prosthodontists (ACP) has developed a classifi cation

system for partial edentulism based on diagnostic findings.


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A ] PATIENT INTERVIEW

1- Structure of interview:

HISTORY TAKING

1.Personal history

2.Chief complaint

3.Phy health and medical history.

4.Psychological health.

5.Frequency of dent examinations.

6.Previous dental treatment.

7. Habits and type of Diet.

8. Patient expectations

2- Objectives:

a. Establishing of a rapport:

We should meet the mind of the patient before we meet his mouth.

b. Gaining insight into the psychological makeup of the patient

(patient attitude):

De Van stated, "Meet the mind of the patient before meeting the mouth

of the patient". Hence, we understand that the patient's attitudes and

opinions can influence the outcome of the treatment.

Dr. MM House proposed the first one in 1950, which is widely

followed. House's Classification Based on patient’s mental attitude,

The philosophical patients. (Well adjusted and easygoing)

The exacting patients. (Precise in everything they do)

The hysterical patients. (Are emotionally unstable and

convinced that they will never be able to wear a prosthesis)

The indifferent patients. (are uncooperative)


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c. Evaluating the systemic disturbances that may affect the

patient’s treatment:

These systemic disturbances include the following:

� Diabetes

� Arthritis

� Paget’s disease

� Acromegaly

� Parkinson’s disease

� Pemphigus vulgaris

� Epilepsy

� Cardiovascular diseases

� Cancer

� Transmissible diseases

Systemic disturbances that can have a significant effect on the treatment

of the patient include the following:

Diabetes: multiple small abscesses and poor tissue tone frequently

accompany uncontrolled diabetes. The diabetic patient often has

excessive rate of bone resorption, hence, frequent relining may be

necessary. And reduced salivary output, which significantly reduced the

ability of patient to wear prosthesis with comfort, and increases the

possibility that caries will occur.

Vitamin deficiency which cause inflammation and bleeding of the

gingiva and fissures in the corners of the mouth.

Oral Malignancies: The most common oral complications of radiation

and chemotherapy for malignancies are mucosal irritation, xerostomia

and bacterial and fungal infections. Tissues having bronze colour and

loss of tonicity are not suitable for denture support. Once the dentures

are constructed, the tissues should be examined frequently for

radionecrosis.

Blood disease e.g. anemia; patients have pale mucosa, sore and red

tongue and gingival bleeding.

Transmissible diseases; e. g. hepatitis and tuberculosis pose a

particular hazard for the dentist, patients and dental auxiliaries.


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Diseases of the Joints: patients with osteoarthritis affecting the finger

joints may find it difficult to insert and clean dentures. With limited

mouth opening and painful movements of the jaw, it becomes necessary

to use special impression trays. It may also become necessary to repeat

jaw relations and make post-insertion occlusal adjustments due to

changes in the joint.

Cardiovascular Diseases: Cardiac patients will require shorter

appointments.

Diseases of the Skin: Skin diseases like Pemphigus have oral

manifestations, which vary, from ulcers to bullae. Such painful

conditions make the denture use impossible without medical treatment.

Neurological Disorders: Diseases such as Bell's palsy and Parkinson's

disease can influence denture retention and jaw relation records. Add

sufficient bulk to buccal surface contour of maxillary RPD to support

flaccid muscles.

Climacteric Conditions :Climacteric conditions like menopause can

cause Tendency to gag, burning sensation, xerostomia, vagueareas of

pain, taste alterations , glandular changes, osteoporosis and psychiatric

changes in the patient.

Pernicious anaemia : Xerostomia , disturbance of taste sensation,

Susceptibility to denture trauma.

Chronic pulmonary disease : Shortness of breath,wheezing, increased

respiratory rate, persistent cough and Occlusal vertical dimension is

difficult to record because of patient ’ s tendency to mouth breathe.

Salivary gland disorders : Xerostomia, painful and burning mucosa

d . Evaluating the drugs that can affect prosthodontic treatment:


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These drugs include the following:

*Anticoagulants

*Antihypertensive agents: cause decrease in salivary flow

*Endocrine therapy: cause sore mouth and discomfort

*Saliva-inhibiting drugs

*Dilantine: cause gingival enlargement

e. Dental history:

The cause of teeth loss: If the teeth were lost because of caries,

special emphasis will have to be placed on oral hygiene

procedures. If the teeth were lost because of periodontal disease,

every effort must be made to discover and eliminate its cause.

If a removable partial denture has been constructed previously for

the patient, it is important to learn as much as possible about the

patient' experience during and following treatment.

Expectation of treatment: If the patient has unrealistic expectation

e.g. a removable partial denture without major connector crossing

the palate) the patient expectation should be changed through

education.

Chewing habits: The patient is asked about the preferred and non

preferred side for chewing. This will determine the amount of

support, retention and bracing of the denture on each side.

Para functional habits: clinching and bruxism has adverse effect

on the denture supporting structures.

f. Ascertaining patient’s expectations of treatment, assessment of

patient motivation and attitudes towards dentures:


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The patient's attitudes and psychological status of the patient have

considerable influence on the success of the treatment.

3- Obstacles:

a. From the dentist:

Not listening to the patient

Choicing words misunderstanding by the patient

Failure to use the obtained information in the treatment of the

patient

b. From the patient:

- Fearful of his condition - Lack of response

4- Aids for successful interview:

1. Dentist attitude and behaviour 2. Phrasing of questions

INFECTION CONTROL

Recommended Infection Control Practices for Dental Treatment

Gloves should be worn in treating all patients.

Masks should be worn to protect oral and nasal mucosa from

splatter of blood and saliva.

Eyes should be protected with some type of covering to protect

from splatter of blood and saliva.

Sterilization methods known to kill all life forms should be used

on dental instruments. Sterilization equipment includes steam

autoclave, dry heat oven, chemical vapor sterilizers, and chemical

sterilants.


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Attention should be given to cleanup of instruments and surfaces

in the operatory. This includes scrubbing with detergent solutions

and wiping down surfaces with iodine or chlorine (diluted

household bleach solutions).

Contaminated disposable materials should be handled carefully

and discarded in plastic bags to minimize human contact. Sharp

items, such as needles and scalpel blades, should be contained in

puncture-resistant containers before disposal in the plastic bags.

B] Clinical examination

PATIENT EVALUATION

• Gait : People with neuromuscular disorders show a different gait.

Such patients will have difficulty in adapting to the denture.

• Age : patients belonging to the fourth decade of life will have good

healing abilities and patients above the sixth decade will have

compro¬mised healing.

• Sex : Male patients are generally busy people whoappear indifferent

treatment. They are only bothered about comfort and nothing else.On

the other hand, female patients are more critical about aesthetics

• Complexion and Personality : Evaluating the complexion helps to

determine the shade of the teeth. Executives require smaller teeth.

• Cosmetic Index : It basically speaks about the aesthetic expectations

of the patient. Based on the cosmetic index, patients can be classified

as:

Class I: High cosmetic index. They are more

concerned about the treatment and wonder if their

expectations can be fulfilled.


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Class II: Moderate cosmetic patients. They are

patients with nominal expectations.

Class III: Low cosmetic index. These patients are not

bothered about treatment and the aes-thetics. It is

very difficult for the dentist to know if the patient is

satisfied with the treatment or not.

Extraoral examination

o Facial examination:

Facial Form

Facial Features

o Muscle Tone

o Muscle Development

o Complexion

o Lip Examination

o TMJ Examination

o Neuromuscular

Examination

Speech

Co-ordination

a-Facial Features :If the face appears collapsed, it indicates the loss of

vertical dimension (VD). Decreased VD produces wrinkles around the

mouth. Excessive VD will cause the facial tissues to appear stretched.

b. Complexion :The colour of the eye, hair and the skin guide the selection

of artificial teeth.

Oral Examination

A complete oral examination should precede any treatment decision. It

should include a visual and digital evaluation of the teeth and surrounding tissue

Sequence for Oral Examination


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An oral examination should be accomplished in the following

sequence:

visual examination,

pain relief and temporary restorations,

oral prophylaxis,

radiographs,

evaluation of teeth and periodontium,

vitality tests of individual teeth,

determination of the floor of the mouth position,

and impressions of each arch.

Relief of pain and discomfort and placement of temporary

restorations

management of acute needs

relieve discomfort arising from tooth defects

Determine as early as possible the extent of caries and to arrest

further caries activity.

By restoring tooth contours with temporary restorations, the impression

will not be torn on removal from the mouth, and a more accurate diagnostic cast

may be obtained.

A Thorough and Complete Oral Prophylaxis

An adequate examination can be accomplished best with the teeth free of

accumulated calculus and debris. Also, accurate diagnostic casts of the dental


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arches can be obtained only if the teeth are clean; otherwise the teeth reproduced

on the diagnostic casts are not a true representation of tooth and gingival contours.

Cursory examination may precede an oral prophylaxis, but a complete

oral examination should be deferred until the teeth have been thoroughly cleaned.

Initial (Cursory) oral examination

Objective:

1. Detection of problems requiring immediate attention

2. Evaluation of oral hygiene

3. Evaluation of caries susceptibility

4. Detection of oroantral or oronasal communications

5. Assessment of applied forces

1. Opposing occlusion.

2. Muscular force and elevator muscle development.

3. Parafunctional habits.

a. Clenching. b. Bruxism

4. Length of edentulous span.

5. History of prosthesis failure.

a. Solder joint failure. b. Porcelain failure.

c. Fractured RPD components.

6. History of poor tissue tolerance.

a. Chronic sore spots.


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b. Excessive bone resorption.

c. Abutment tooth mobility.

d. Fracture or attrition of natural teeth.

e. Attrition, abrasion, erosion, abfraction

Definitive visual oral examination:

Complete oral examination to evaluate the following:

A] The teeth and periodontium:

1. Caries and existing restorations: All carious teeth must be restored prior to

starting definitive prosthodontic treatment,

2. Pulp to detect pulpitis or pulp necrosis

3. Sensitivity to percussion

4. Mobility and C/R ratio: The degree of mobility of all teeth should be

recorded using a scale commonly used for classifying mobility:

■ Class 1: A tooth demonstrates greater than normal movement, but less

than 1 mm of movement in any direction.

■ Class 2: A tooth moves 1 mm from normal position in any direction.

■ Class 3: A tooth moves more than 2 mm in any direction, including

rotation or depression. A change from normal physiologic movement may

indicate traumatic occlusion or periodontal disease. Teeth exhibiting

Class 3 mobility have a poor prognosis and usually will require

extraction.

Causes:

Trauma from occlusion


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Inflammatory changes of the PDL

Loss of alveolar bone support

Treatment:

Scaling

Learning and ascertaining good oral hygiene

Splinting when:

• All the remaining teeth have reduced support

• Only two or three widely spaced retainable teeth

• The first premolar and all molars have been lost and the

second premolar is to serve as the abutment

5. Periodontium:

The health of the PDL is determined by findings that need periodontal

treatment are:

1. Pocket depth in excess of 3 mm

2. Furcation involvement

3. Deviations from normal colour and contour in gingiva indicating

gingivitis

4. Marginal exudate

5. Less than 2 mm of attached gingiva

6. Pulling of muscle or frena on attached gingiva


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B] . Oral mucosa:

Pathologic changes

Tissue reactions to the wearing of old prosthesis:

Soft tissue displacement

Palatal papillary hyperplasia: It is associated most often with a

poorly fitting prosthesis that has been worn for a prolonged

periods. It consists of numerous small papillary growths.

Epulis fissuratum: It is a tumour like hyper plastic growth in the

sulcus caused by an ill- fitting or overextended border of a

removable prosthesis.

Denture stomatitis: It is characterized by generalized

erythematic for all the tissues covered by the prosthesis.

Candida albicans has been shown to be present in much higher

percentage of denture stomatitis. Traumatic occlusion, poor fit

of the prosthesis, poor oral hygiene and continuous wearing of

the prosthesis have all been suggested as contributing factors to

this condition.

C]. Hard tissue abnormalities:

Torus palatinus: Removal of a torus palatinus is not usually necessary; a

major connector can be designed to circumvent the torus.

Torus mandibular. It is exostoses, usually occurring bilaterally on the

lingual surface of the body of the mandible.

Undercuts and bulbous maxillary tuberosities:

The effect of some undercut areas may be minimized by:

o Change in the path of insertion of the RPD in case of unilateral undercut.


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o Relieving the denture base or reducing the length of the denture border

o Surgical correction of undercuts.

o Flexible denture base or flexible border

o Reduce length of denture border

The mylohyoid ridge: Some of these ridges are felt to be

pronounced and the soft tissue covering is thin and is easily

traumatized by insertion and removal of prosthesis.

D]. Soft tissue abnormalities:

Labial frenum: If the frenum is attached highly at the crest of the

ridge, or it was bulky, the notch in the maxillary denture should be

done to accommodate this frenum shape and position.

Lingual frenum: It can greatly compromise the rigidity and

adjustement of the major connector.

Flabby gingiva: Atrophy of the residual ridge does occur

occasionally, and the gingiva loses its bony support and becomes

freely, Tnis area should be evaluated to determine whether it requires

conservative treatment or surgical removal.

Tongue size & mobility: The tongue should be examined for :

• Size: Presence of a large tongue decreases the stability of lower

denture and ate also a hindrance to impression making. Tongue-biting is

common after insertion of the denture. A small tongue does not provide

adequate lingual peripheral seal.

• Movement and coordination: Tongue movements and coordination

are important to register a good peripheral tracing. They are also

necessary in maintaining the denture in the mouth during functional

activities like speech, deglutition and mastication, etc.

E] Occlusal relationships:

It is the relation between the opposing teeth and between the teeth and


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the opposing ridge is examined for.

a- Available interarch space for placement of artificial teeth.

b- The degree of anterior vertical overlap.

c- Super eruption and tilting of the remaining teeth.

d- Cuspal interference.

F] - Temporomandibular joint (TMJ) examination:

TMJ disorders can be detected by one or more of the following signs:

a- Reduced inter incisal opening (Normal maximum opening is 55mm +

15mm).

b- Pain and tenderness over the TMJ at rest and during movement.

C- Clicking during opening and closing.

d- Midline deviation during wide opening.

e- Muscle pain and tenderness.

f- Headache and ear pain.

G]. Quality and quantity of saliva:

� Dry mouth >>>> no lubricating effect >>>> saliva substitute

� Thick and ropy saliva or copious amounts of serous saliva

>>>> problems during impression.

Thick ropy saliva alters the seat of the denture because of its tendency

to accumulate between the tissue and the denture. Thin serous saliva

does not produce such effects.

Xerostomic patients show poor retention and excessive tissue

irritation whereas excessive salivation complicates the clinical

procedures. use of synthetic saliva, with a carboxymethyl cellulose

base, which can be enriched with fluoride in an effort to counteract

caries. Frequent use provides an excellent means of maintaining high


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fluoride intraorally for long periods of time, thus enhancing the

remineralization of incipient caries.

H] . Space for mandibular major connector:

The superior margin of the connector should be located 3 mm

below the free gingival margins of the mandibular teeth >>>>>

to avoid damage to the gingival tissues.

The inferior border of the connector should be positioned at or

slightly above the position of the active floor of the mouth

>>>>> to prevent interference with the functional movements

of the floor of the mouth and to help avoid the packing of food

under the major connector.

A minimum of 7 to 8 mm. of space should be available if a

lingual bar major connector is to be used. Available space is

measured with a calibrated periodontal probe (William's

probe) , while the patient raising the tongue toward the palate.

Measurements are made at several positions; the probe is then

used to transfer it to the cast.

I] Oral hygiene and caries susceptibility:

Evaluation of patient's oral hygiene is critical to the prognosis of the

patient's treatment. Disclosing tablets or solution is used to detect plaque,

which will indicate the patient motivation towards oral hygiene.

The presence of large number of restored teeth, signs of recurrent caries

and evidence of decalcification indicate that the patient is susceptible to caries.

J]. Modification Spaces

For short spans (<=3 missing teeth), natural tooth, implant-

supported fixed prostheses, and removable partial dentures can generally

be considered.


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Longer span modification spaces (>=4 missing teeth) present a

greater challenge for natural tooth-supported fixed prostheses.

Consequently, the options for treatment are the removable partial denture

or the implant supported prosthesis.

K] Abutments With Guarded Prognoses

If the prognosis of an abutment tooth is questionable, or if it becomes

unfavourable during treatment, it might be possible to compensate for its

impending loss by a change in denture design.

It is sometimes possible to design a removable partial denture so that a

single posterior abutment, about which there is some doubt, can be retained

and used at one end of the tooth-supported base. Then if the posterior abutment

is lost, it could be replaced by adding an extension base to the existing denture

framework. Such an original design must include provisions for future indirect

retention, flexible clasping of the future abutment, and provision for

establishing tissue support.

Anterior abutments that are considered poor risks may not be so freely

used because of the problems involved in adding a new abutment retainer when

the original one is lost. It is rational that such questionable teeth be condemned

in favor of more suitable abutments, even though the original treatment plan

must be modified accordingly.

Kennedy Class II, mod I in which molar abutment has a guarded prognosis. Premolar clasp assembly is a

mesial rest, distal guide plane, and wrought wire retainer design that will accommodate future distal extension

movement.


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L] Examination of old denture:

a- the design and quality of construction should be noted and any associated

problems in relation to gingival and mucosal inflammation or to decalcification

of contacting tooth surfaces.

b- It is important to evaluate whether the denture is still fit accurately against

the teeth and under lying mucosa or not.

C -Radiographic survey:

1. Complete mouth periapical and bite-wing survey.

2. Panoramic.

3. Obtain previous radiographs if possible for purpose of comparison.

1. Examination of residual ridge to evaluate:

All radiolucent and radiopaque areas that vary from normal ranges

to determine whether a pathologic condition is present.

Root fragments and other foreign bodies to determine whether

their removal is indicated.

Un erupted third molars to determine whether they should be

retained or removed.

Evaluate quantity of bone.

oAlveolar.

oResidual ridge.

oBasal.

a. Bone Index (bone factor):

The bone factor provides an assessment of the relative response

of bone to stimulation or irritation. This assessment is made by

analyzing bone index areas.

Bone index areas are those areas of bony support which disclose

the reaction of bone to increased force, e.g. areas of bone around

abutment teeth or any other teeth subjected to increased loading.


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These areas are compared to areas of bone around teeth in

normal function without increased loading.

A similar consideration may be given to the residual ridge or an

edentulous area of bone supporting a complete or an extension base

removable partial denture.

Evaluation of past response is important in predicting the future

potential for dento-alveolar (abutment teeth) and muco-osseous (ridge)

resistance to forces transmitted by an RPD.

The bone index is difficult to determine from radiographs alone.

The history of the patient is important in evaluating the rate of

resorption that may be expected based on previous occurrences. The

length of time from previous extractions together with morphological

changes in the residual ridge gives some indication of the host response

to various forces.

b. Bone Density

Denser bone (more highly mineralized) offers greater resistance to

resorption. The reduced rate of resorption of cortical bone compared to

cancellous bone is likely due to the degree of cellularity and

mineralization, which may influence metabolic activity, as well as to bone

factors. These factors appear to account for the pattern of resorption of the

residual ridges in the edentulous or partially edentulous patient.

In the mandibular arch the external oblique ridge, the mylohyoid ridge

and the genial tubercles, which are areas of muscle attachments, continue

to resist resorption even when the residual ridge is greatly resorbed.

The presence of dense cortical bone is often the result of applied forces

arising from ligamentous or muscle attachments which provide tension to

the underlying bone.

c. Extrinsic bone factors. Localized forces applied to bone.


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1. Pressure-Bone tends to resorb in response to compressive forces.

The rate of resorption most likely depends on the bone density,

intrinsic bone factors, and the nature of the applied forces and on the

interaction of pressure and tension. The remodelling that occurs under

the extension base of a removable partial denture is an example of

pressure induced resorption.

11. Tension-Bone under tensional stimuli tends to increase in density

and in some instances may increase in quantity. The lamina dura is a

response to tensional forces transmitted by the periodontal ligament.

Orthodontic movement of teeth is a good example of the pressure -

tension theory. The lamina dura resorbs on the pressure side and bone

apposition occurs on the opposite side.

d. Intrinsic bone factors which May influence the rate of resorption.

Genetic.

Hormonal.

Nutritional.

Pathologic.

Biochemical.

Other.

Wolff’s law of bone physiology-

Intermittent stimulation can cause bone apposition, constant stimulation

(irritation) causes bone resorption

Theilmann’s diagonal law of occlusion-

An interceptive posterior occlusal contact can cause elongation of the

teeth in the arch diagonal to the prematurity

2. Examination of remaining teeth with special attention focused on

prospective abutments to evaluate:

The presence and extent of caries and the relation of the carious lesion

to the dental pulp


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Existing restorations to determine the adequacy of proximal contours

and the presence of overhanging or deficient margins and recurrent

caries.

Root canal fillings: an abutment for a distal extension that is

endodontically treated carries a greater risk for complications than a

similar tooth not involved in removable partial denture function.

Root length, size and form

Teeth with multiple and divergent roots will resist stresses better

than teeth with fused and conical roots, because the resultant

forces are distributed through a greater number of periodontal

fibers to a larger amount of supporting bone

C/R ratio: The radiographic crown - root ratio is a commonly used

index for classifying the degree of existing support for teeth being

evaluated as probable abutments.

The length of the tooth occlusal from the crest of the alveolar

bone is compared with the length of the tooth root apical from the

alveolar crest, and the comparison is expressed as an approximate ratio.

A tooth with normal, undiminished alveolar support will have a

crown - root ratio of approximately 1:2. As a general diagnostic guide, a

tooth with a crown - root ratio of more than 1:1 is considered to have an

unfavorable prognosis as an abutment tooth.

Unerupted third molars: should be considered as prospective future

abutments to eliminate the need for a distal extension removable partial

denture

PDL space: The width of the periodontal ligament around the roots of

the teeth is of significance in evaluating the stability of the teeth. A thin,

uniform ligament space is a more favorable sign than is a widened,

irregular space.


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Widening in periodontal ligament space: indicate trauma,

mobility or heavy function

Lamina dura: The lamina dura is the thin layer of hard cortical bone

that normally lines the sockets of all teeth. In a roentgenogram, the

lamina dura is shown as a radiopaque white line around the radiolucent

dark line that represents the periodontal membrane.

Uneven lamina dura: During the active tipping process, the

lamina dura is uneven, with evidence of both pressure and tension on the

same side of the root. For example, in a mesially tipping lower molar the

lamina dura will be thinner on the coronal mesial and apicodistal aspects

and thicker on the apicomesial and coronal distal aspects because the

axis of rotation is not at the root apex but is above it. The lamina dura on

the side to which the tooth is sloping becomes uniformly heavier, which

is nature's reinforcement against abnormal stresses.

Partial or total absence of lamina dura may be found in

systemic disorder as: hyperparathyroidism and Paget disease. When

systemic disease is associated with faulty protein metabolism and when

the ability to repair is diminished, bone is resorbed and the lamina dura

is disturbed. Therefore the loading of any abutment tooth must be kept

to a minimum inasmuch as the patient's future health status and the

eventualities of aging are unpredictable.

Thickening of lamina dura : occur if the tooth is mobile , has

occlusal trauma or is under heavy function.

D] DIAGNOSTIC CASTS

Impressions should be made for making accurate diagnostic casts to be

mounted for occlusal examination.

A diagnostic cast should be an accurate reproduction of all the

potential features that aid diagnosis. These include the teeth locations, contours,

and occlusal plane relationship; the residual ridge contour, size, and mucosal

consistency; and the oral anatomy delineating the prosthesis extensions


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(vestibules, retromolar pads, pterygomaxillary notch, hard and/or soft palatal

junction, floor of the mouth, and frena). Additional information provided by

appropriate cast mounting includes occlusal plane orientation and the impact on

the opposing arch; tooth-to-palatal soft tissue relationship and tooth-to-ridge

relationship, both vertically and horizontally.

A diagnostic cast is usually made of dental stone because of its strength,

and it is less easily abraded than is dental plaster.

The diagnostic cast impression is usually made with an irreversible

hydrocolloid (alginate) in a stock (perforated or rim lock) impression tray.

Purposes of accurate diagnostic casts:

1. Analysis of the contour of hard and soft tissues of the mouth

2. Preliminary design of the partial denture .Determine of the types of

restorations to be placed on the abutment teeth

3. Determine the need for surgical correction of exostoses, frena,

tuberosities and undercuts

4. Used to permit a topographic survey of the dental arch that is to be

restored by means of a removable partial denture and the proposed design

is drawn on them. To determine the need for mouth preparation including

(a) Proximal tooth surfaces, which can be made parallel to serve as

guiding planes;

(b) Retentive and non retentive areas of the abutment teeth; (c)

areas of interference to placement and removal; and

(d) Esthetic effects of the selected path of insertion.

5. Serve as a plan for the placement of restorations, the recontouring of

teeth, and the preparation of rest seats.


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6. Designed casts aid in the presentation of the proposed treatment to the

patient.

7. Permitting a view of the occlusion from the lingual and buccal

aspects.

8. Individual impression trays may be fabricated on the diagnostic casts

8. Used as a constant reference as the work progresses. Pencilled marks

indicating the type of restorations, the areas of tooth surfaces to be

modified, the location of rests, and the design of the removable partial

denture framework along with the path of placement and removal, all may

be recorded on the diagnostic cast for future reference

9. Diagnostic casts on a suitable articulator permit analysis of:

Occlusion,

The adequacy of interarch space

The presence of over erupted or malposed teeth

The presence of tuberosity interferences.

10. Unaltered diagnostic casts should become a permanent part of the

patient's record because records of conditions existing before treatment

are just as important as are preoperative radiographs.

Analysis of mounted diagnostic casts:

The mounted diagnostic casts provide visual access from all directions and

enable the dentist to make a detailed analysis of the patient’s occlusion.

1. Mounting of maxillary cast to articulator

It is better that the casts be mounted in relation to the axis-orbital

plane to permit better interpretation of the plane of occlusion in relation to

the horizontal plane. Although it is true that an axis orbital mounting has


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no functional value on a nonarcon instrument because that plane ceases to

exist when opposing casts are separated, the value of such a mounting lies

in the orientation of the casts in occlusion. MAC

2. Jaw Relationship Records for Diagnostic Casts (Vertical dimension of

occlusion and centric jaw relation record)

One of the first critical decisions that must be made in a removable

partial denture service involves the selection of the horizontal jaw

relationship to which the removable partial denture will be fabricated

(centric relation or the maximum intercuspal position).

It is recommended that deflective occlusal contacts in the maximum

intercuspal and eccentric positions be corrected as a preventive measure.

If most natural posterior teeth remain—and if no evidence of

TMJ disturbances, neuromuscular dysfunction, or periodontal

disturbances related to occlusal factors exists—the proposed

restorations may safely be fabricated with maximum

intercuspation of the remaining teeth. When diagnostic casts are

hand related by maximum intercuspation for purposes of

mounting on an articulator, it is essential that three (preferably

four) positive contacts of opposing posterior teeth are present,

having wide spread molar contacts on each side of the arch.

When most natural centric stops are missing, the proposed

prosthesis should be fabricated so that the maximum intercuspal

position is in harmony with centric relation. Correction of the

remaining natural occlusion to create a coincidence of centric

relation and the maximum intercuspal position is indicated in

such situations.

Clinical situation suggest construction of partial denture at centric

relation:


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1- Absence of posterior tooth contact

2- When all posterior tteeth will be restored with fixed

restoration

3- Few remaining posterior contacts

4- Clinical symptoms of occlusal trauma

5- Coincidence of centric jaw relation and maximum

intercuspal position

Materials available for recording centric relation are

(1) wax;

(2) modeling plastic;

(3) quick-setting impression plaster;

(4) metallic oxide bite registration paste;

(5) polyether impression materials;

(6) silicone impression materials.

3. Inspection of:

Occlusal plane

Occlusion

Tipped or malposed teeth

Traumatic vertical overlap

The presence of tuberosity

interferences

interarch space

Malrelation of jaws

Diagnostic wax up

Interarch distance

Lack of sufficient interarch distance for the placement of artificial teeth:

Caused by


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A maxillary tuberosity that is too large in vertical height.

A segment of teeth that has been unopposed for a prolonged period will

frequently overerupt, carrying the alveolar process with it. Subsequent

removal of the teeth will produce a situation in which it is impossible to

establish a functionally and aesthetically acceptable plane of occlusion.

Management

The surgical reduction of the vertical height of the tuberosity and at times

the adjacent residual ridge is necessary if satisfactory replacement of the

missing teeth is to be accomplished. The area and amount of tissue that should

be removed can be indicated on the diagnostic east. This provides an excellent

guide for the oral surgeon or dentist who performs the surgical correction. The

radiographs are a valuable aid in planning the surgical of fibrous tissue.

Healing is usually complete in 7 to 10 days. The healing period is extended to 2

to 5 weeks when bone removal is necessary.

Maxillary tuberosity interferences.

The maxillary tuberosity area may be undercut on one or both

sides.

The path of insertion of a complete denture can usually be compatible

with an unilateral tuberosity undercut, but a removable partial denture, with a

more controlled path of insertion, presents greater problems.

Management

The undercut must be evaluated with the aid of the dental surveyor.

With the cast on the surveying table at the predetermined path of insertion, a

determination is made as to the amount of relief that will be required in the

denture if the undercut is not reduced. Moderate to severe tuberosity undercuts

usually require surgical correction with bone removal.

bulbous tuberosities


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Occasionally the tuberosities are so bulbous that the coronoid process

of the mandible may actually rub against the tuberosity during functional

movements.

Management

Surgical reduction of such a tuberosity is necessary if the patient is to

wear a removable partial denture.

Occlusal plane

1. Irregular occlusal plane: (because extrusion of one or more unopposed

teeth)

Management

Available treatments depend on the degree of extrusion and the condition of the

tooth:

• Enameloplasty can effectively reduce a moderately extruded tooth.

Approximately 2 mm of enamel can be removed in many situations. At times

the reduction of a single cusp improves the occlusal plane.

• Placement of an extracoronal cast metallic restoration If the extrusion is

greater than 2 mm or if the tooth does not lend itself to enameloplasty, The

degree of reduction is limited as much or more by the clinical crown length of

the tooth as by the size of the dental pulp.

The clinical crown length can often be increased by appropriate

periodontal therapy if crown lengthening is needed to obtain adequate retention

for the restoration. Useful crown lengthening procedures include tissue

shrinkage, gingivectomy, apical positioning flaps, and osseous surgery.

• Endodontic therapy and crown, when sever reduction to be made.

Extruded teeth can also be repositioned through orthodontic tooth movement

procedures.


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• Severely extruded teeth such as those contacting the opposing ridge present

greater problems. If the alveolar bone has followed the eruption of the

offending tooth, it may be necessary to extract the tooth and remove the

surrounding bone.

• At times endodontic treatment and & drastic reduction of the tooth will enable

it to be used as an overdenture abutment. This treatment can provide valuable

support for a distal extension base. Extruded teeth must always be evaluated

with the occlusal plane in mind.

• Retention of a tooth that will jeopardize the development of a functional and

aesthetic occlusal plane is rarely justified.

2. Malposed occlusal plane: (because of extrusion of an entire segment of an

arch with concomitant drop of the alveolar process):

Extrusion of maxillary molars or premolars, or both, with drop of the alveolar

process till contact the opposing residual ridge, causing obvious space

problems and malposition of the occlusal plane.

Management

• One approach to treatment is the removal of the extruded teeth in

conjunction with an extensive alveolectomy.

• Consideration should be given to the use of one of the newer orthognathic

surgical procedures. A posterior segmental osteotomy can be effective in

correcting the problem. Close cooperation and communication between the

prosthodontist or dentist and the oral surgeon are essential. Because the dentist

must construct the prosthesis for the postsurgical tooth and ridge relations, he

should determine the ideal position of the segment. The oral surgeon must

determine the procedures and techniques to employ in making the correction.


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Anterior maxillary osteotomy can also be effective in repositioning the

anterior teeth and alveolar ridge for patients with severe protrusion of the

anterior teeth or deep vertical overlap.

Malrelation of jaws:

Severe malrelation of the jaws can prevent the restoration of adequate function

and esthetics.

Management:

Several maxillary and mandibular osteotomy procedures are useful in

correcting these problems. Close cooperation, consultation, and communication

between the prosthodontist or dentist and the oral surgeon are essential in

treating patients with malrelation of the jaws.

Tipped or malposed teeth

Management:

• Limited orthodontic procedures for minor tooth movement can be used to

upright the tipped tooth to allow the placement of an artificial tooth of more

normal size.

• Teeth in severe buccoversion or linguoversion should be evaluated. At times

the removal of the malposed tooth will simplify the design of the prosthesis.

Traumatic vertical overlap

Classification:

Akerly (1977) has classified traumatic vertical overlap into the following

four basic types:

Type I -The mandibular incisors extrude and impinge into the palate.

Type II-The mandibular incisors impinge into the gingival sulci of the

maxillary incisors.


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Type Ill-Both maxillary and mandibular incisors incline lingually with

impingement of the gingival tissues of each arch.

Type IV-The mandibular incisors move or extrude into the abraded

lingual surfaces of the maxillary anterior teeth.

Clinical symptoms:

Abrasion,

Mobility,

Migration of the teeth,

Inflammation and ulceration of the gingiva and oral mucosa.

Management:

1. Early recognition and treatment with orthodontic or combined

orthodontic and orthognathic surgery.

2. Establishing stable occlusal contacts at centric jaw relation

3. With advanced clinical symptoms, the removal of teeth is indicated.

Alveolectomy at the time of extraction will help provide space for some

improvement.

4. If the teeth are retainable, reduction of the length of the mandibular

anterior teeth will relieve symptoms temporarily.

5. A treatment prosthesis that plates the lingual surfaces of the maxillary

anterior teeth must be used to prevent further extrusion of the mandibular

incisors until more definitive treatment can be accomplished.

6. Definitive treatment is based on:

The degree of horizontal overlap,

The number and the occlusal relationships of the remaining teeth


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The health of the supporting structures.

The need for RPD and its type and location.

� If all the maxillary teeth are present and have healthy support, it may

be possible to build up the cingula of the anterior teeth with cast

restorations >>>>> not feasible if the horizontal overlap is too great.

� If a maxillary removable partial denture is indicated, the major

connector can be extended onto the lingual surfaces of the anterior

teeth with a thin plate of metal >>>>> a vertical stop to prevent further

eruption of the mandibular anterior teeth.

� If only a mandibular removable partial denture is required, a lingual

plate major connector can be designed to prevent continued eruption of

the anterior teeth. The plating should cover the cingula of the teeth

with projections extending to the contact points. Rest seats should be

placed on the canines or first premolars to prevent labially directed

forces from being applied to the teeth.

Occlusion

The mounted diagnostic casts are also used for an evaluation of the patient’s

occlusion. The information obtained from the analysis of the occlusion should

be correlated with other clinical findings.

Occlusal interferences:

Partially edentulous patients have an even greater probability of having

premature occlusal contacts because of the drifting and migration of teeth that

usually accompany the loss of continuity of the dental arch.

Bruxism:

Severe bruxism can injure the teeth, the periodontium, and the

Temporomandibular joint and may initiate muscle spasm, pain, or discomfort.


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The most common causes of bruxism are:

1. Occlusal interferences between centric jaw relation and centric

occlusion and

2. Balancing side contacts.

The clinical symptoms of traumatic occlusion follow:

• Excessive wear of the teeth, which may include chipping or

fracture of the teeth.

• A change in, or a loss of, the supporting structures, which may

include increased mobility, tooth migration, and pain during and

after occlusal contact.

• Involvement of the neuromuscular mechanism of the

temporomandibular joint, which may include muscle spasm,

muscle pain, and joint symptoms.

The radiographic signs of traumatic occlusion follow:

• Widening of the periodontal ligament space with either

thickening or loss of lamina dura.

• Periapical or furcation radiolucency.

• Resorption of alveolar bone.

• Root resorption.

Management of occlusal interferences and bruxism:

Occlusal equilibration: it is the selective grinding or coronal

reshaping of teeth with the intent of equalizing occlusal stress,

producing simultaneous occlusal contacts, or harmonizing cuspal

relations.


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Occlusal equilibration should not be accomplished for every

patient with occlusal interferences. Many patients have a great

enough resistive capacity that occlusal forces are not destructive

regardless of the occlusal relationships of the teeth. If occlusal

equilibration were accomplished on these individuals, an “occlusal

sense or continued “awareness of the occlusion” may be developed

E. Consultation requests:

A.THE PATIENT SHOULD BE MADE AWARE OF THE FOLLOWING.

1. The nature and severity of the existing dental problems.

2. Any limitation in function, phonetics, esthetics, and longevity related to the

prosthesis.

3. The physical aspects of the prosthesis with regard to bulk and tissue

coverage.

4. Any treatment options that may be considered.

5. The risks, benefits and alternatives related to any treatment plan.

B . PATIENT MUST UNDERSTAND AND ACCEPT RESPONSIBILITY

FOR PREVENTIVE HOME CARE AND PROFESSIONAL RECALL.

F. Development of treatment plane:


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III-TREATMENT PLANE IN RPD

Elimination of Infection

Sources of infection like infected necrotic ulcers, periodontally weak

teeth, and nonvital teeth should be removed. Infective conditions like

candidiasis, herpetic stomatitis, and denture stomatitis should be treated and

cured before commencement of treatment.

Elimination of Pathology

Pathologies like cysts and tumours of the jaws should be removed or

treated before complete denture treatment begins. The patient should be

educated about the harmful effects of these conditions and the need for the

removal of these lesions. Some pathologies may involve the entire bone. In

such cases, after surgery, an obturator may have to be placed along with the

complete denture.


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Preprosthetic Surgery

Preprosthetic surgical procedures enhance the success of the denture.

Some of the common preprosthetic procedures are:

Labial frenectomy.

Lingual frenectomy.

Excision of denture granulomas.

Excision of flabby tissue.

Reduction of enlarged tuberosity.

Alveoloplasty.

Alveolectomy

Reduction of genial tubercle.

Reduction of mylohyoid ridge.

Excision of tori.

Vestibuloplasty.

Lowering the mental foramen.

Ridge augmentation procedures.

Implants

Tissue Conditioning

The patient should be requested to stop wearing the previous denture for

at least 72 hours before commencing treatment. He/she should be taught to

massage the oral mucosa regularly.

Special procedures should be done in patients who have adverse tissue

reactions to the denture. Denture relining material should be applied on the

tissue side of the denture to avoid denture irritation. Treatment dentures or

acrylic templates can be prepared to carry tissue-conditioning material during

the treatment of abused tissues.

Nutritional Counseling

Nutritional counseling is a very important step in the treatment plan of a

complete denture. Patients showing deficiency of particular minerals and


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vitamins should be advised a proper balanced diet. Patients with vitamin B2

deficiency will show angular cheilitis. Prophylactic vitamin A therapy is given

for xerostomic patients. Nutritional counseling is also done for patients show-

ing age-related changes such as osteoporosis.

PROSTHODONTIC CARE

The type of prosthesis, denture base material, anatomic palate, tooth

material and teeth shade should be decided as a part of treatment planning.

Depending upon the diagnosis made, the patient can be treated with an

appropriate prosthesis. For example:

For a patient with few teeth, which are likely to be extracted an immediate

or conventional, definitive or interim, implant or soft tissue supported

dentures can be given.

For patients with acquired or congenital deformities, a denture with an

obturator can be given.

In addition to the initial diagnosis the success or failure of denture

depend on also the treatment planning. In partially edentulous patient, there are

5 alternatives

1-fixed bridge.

2-removable partial denture

3-complete denture .

4-any combination.

5-leave condition as it.

6.Overdenture

1-fixed bridge

Indication:

A-GENERAL INDICATIONS:


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1-for eliminating psychological trauma.

2-in pt suffering from sudden bout of unconsciousness as in epilepsy.

3-for orthodontic needs.

4-as apart of overall periodontal and occlusal therapy.

5-for better correction of speech.

6-for better function and stability.

B-LOCAL INDICATIONS:.

1-healthy abutments with suitable c/r ratio.

2- if the abutment requires restoration.

3- short span.

4-lack of space for a suitable replacement.

5-if the morphology of the abutment need changing.

6-unfavourable angulations of the teeth for R P D ( Telescopic bridge)

Contraindication:

A-GENERAL CONTRAINDICATIONS:

1-inability of the patient to cooperate.

2-young or very old patient.

In young, poor prognosis because of:

• Short clinical crown

• Large pulp

• High caries rate

• Increase liability to trauma

• some teeth are not in

occlusion

• incomplete growth of the

bone of the jaw


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in very old patient :

• lack of P.D.L resiliency

• increase abrasion

• poor cooperation

• the expectation of life short

• excessive bone resorpation

3- contraindication to L.A

4- high caries rate

5-gingival and periodontal disease

6- bad oral hygiene

7- un favorable reaction to the M.M

B- LOCAL CONTRA INDICATION

1- long span

2- when the bridge will occlude with opposing teeth on its end or 1/2 or less of

its length

3- unfavorable supporting structures of the abutment

4- any apical infection

5- insufficient effective root surface area

6- weak crowns or small formed abutment

7- deep sub gingivally carious abutment

8- extensive bone resorpation of edentulous ridge

9- unfavorable tilting or rotation of abutment

10- increase possibility of further tooth loss in the same arch

11- if the form of the bridge is an arc of a circle


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12- abnormal occlusion, abnormal forces

2-Complete denture

Indication:

1-poor abutment

2- poor oral hygiene and rampant decay

3- cosmetically unacceptable ant. Teeth

4- rejection of professional advice

5- refusal mouth preparation

6- poor alignment

7- radiation therapy

3- Removable partial denture

Indicaton

1-long span with well supported abutment

2- free end saddles

3- multiple missing ant. teeth

4- weak abutment

5- presence of deep subgingival caries on abutment

6- increased caries index

7- need of cross arch stabilization (bracing) of remaining teeth

8- immediate replacement


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9- excessive bone loss

10- need for complete denture in future( due to increase possibility of further

tooth loss)

11- physical or emotional problems of pt.

12- patient desire (economic and time and preserve of sound teeth )

13- youth (< 17 y.) and old age

14- restore facial contour

15- alteration vertical dimension

16- transitional prosthesis

17- obdurate palatal cleft

18- extreme atrophic ridge

19- patient with previous unsatisfactory prosthetic

20- diabetic pt

Containdications:

A-Intraoral contraindication

1-poor oral hygiene

2- advanced P.L disease

3- increase caries rate

4- if morphology of abutment need changing (fixed)

5- unfavorable angulations of the teeth

6- short span (fixed)

B-Patient contraindication


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1- un cooperative pt.

2- with sudden pouts & unconsciousness or fits

3- low and bad attitude

4- poor general health

5- patient unable to pay money

EXTRAORAL FACTORS THAT INFLUENCE TYPE OF

PROSTHODONTIC SURFACE:

1-AGE:

a- young patient under 25 y.

• Not be rendered completely edentulous.

• Avoid extraction

• Age of man chronologic

Physiologic

psychologic

b- old patient :

need special care.

2-GENERAL HEALTH:

• Poor health : trauma

• Interim partial denture : prostheses of choice

• Temporary partial denture instead of fixed partial denture

• Rebase and relief & tissue materials need

3- SEX:


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Female:

• Higher vanity index

• Avoid loss of teeth and age changes

• Need more esthetics ( P A P D avoid R P D )

• First look is very important

4- ECONOMIC CONSIDERATION

R P D may need root canal treatment and crown inlays thus more cost.

5- SOCIOECONOMIC BACKGROUND

6- DESIRES AND ATTITUDE OF PATIENT

7- OCCUPATIONAL FACTORS

8- TIME FACTORS

Removable partial denture . may be used for long term prognosis, the best

R.P.D, service for many years.

Or for short term prognosis and in future the patient need complete denture,

must be simple in design and permit the addition of future teeth (additive

partial denture)

This temporizing treatment gives the patient experience in denture wearing and

in adaptation to artificial dentition.

The additive partial denture is particularly indicated in lower jaw. It is a

devisable to retain standing lower teeth, especially single standing canines to

delay recourse to the full lower denture and preserve the alveolar ridge

( support ). Overdenture: partial or complete overdenture


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Clinical factors related to metal alloys used for removable partial denture

frameworks: see denture base

Various alloys can be considered for use, Practically all cast frameworks

for removable partial dentures are made from a chromium-cobalt alloy.

The choice of the alloy from which the framework of a removable

partial denture will be constructed is logically made during the treatment-

planning phase.

Mouth preparation procedures, especially the recontouring of abutment

teeth for the optimum placement of retentive elements, depend to a large extent

on the modulus of elasticity (stiffness) of a particular alloy.

Questions

1. Disscuss factors affecting selection the type of prostheses

2. Mention types of removable prostheses

1 Diagnosis of pd patients fayad

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