Prosthodontics

Impression And Mouth Preparation Long Essays

Question 1. Define impression. Discuss in detail the most widely accepted technique of making an impression in complete dentures.
Answer:

Impression:

A complete denture impression is a negative registration of the entire denture bearing, stabilizing & border seal areas present in the edentulous mouth.

Impression Techniques:

1. Mucostatic
2. Mucocompressive
3. Selective pressure technique
   • It is the most widely accepted impression technique
   • In this technique, forces are confined to stress-bearing areas whereas non-stress-bearing areas are relived

Technique:

• Primary impression is made with overextended borders Primary cast is prepared from it
• Undercuts are blocked with wax on cast Relief wax is adapted over relief areas on cast
• A spacer is adapted throughout the extent of the special tray
• Separating media like cold mold seal or tin foil is applied over cast
• Special tray with a handle is fabricated
• It should be 2 mm short of sulcus
• Materials used for it are: Shellac, cold cure acrylic, Type II impression compound
• Wax spacer is then scraped off
• Border moulding is done using greenstick compound
• Relief wax is removed
• Escape holes are made over the tray
• Secondary impression material is loaded over the tray
• It is then seated in the patient’s mouth and the secondary impression is made.

Materials Used:

Question 2. Define impression.
Or
Discuss various impression procedures in the complete denture.
Or
Add a note on selection of impression materials.
Answer:

Impression:

A complete denture impression is a negative registration of the entire denture bearing, stabilizing & border seal areas present in the edentulous mouth.

Impression Procedures:

1. Custom Tray Impression:
   • Design a custom tray with a spacer
   • It should be 2 mm short of sulcus
   • Border molding is done
   • It results in recording the sulcus in dynamic function
   • Spacer is scraped
   • The impression is recorded by ZOE
   • It results in recording the stress-bearing areas un- der pressure & non stress-bearing ares are relieved.
2. Tray Compound:
   • The impression made using tray impression compound
   • The impression is refined & trimmed
   • The metal wire is attached to tray compound to act as a handle
   • Treat it as a custom tray
   • Border molding done
   • Wash impression is made over it

Read And Learn More: Prosthodontics Question And Answers

Selection Of Materials:

• They should be fluid enough to adapt to oral tissues
• Should be viscous enough to be contained in the tray that is seated in the mouth
• While in the mouth, they should set into a rubbery or rigid solid in a reasonable amount of time
• The set impression should not tear or distort when removed
• The impression made should be dimensionally stable
• Stability should be maintained after the removal of a cast so that a second or third cast can be made
• The material should be biocompatible
• It should be cost-effective
• Should be nontoxic
• Should be acceptable to patients with pleasant odor and color
• Should have adequate shelf life Easy to use with minimum equipment Should have adequate strength

Question 3. Define retention, stability, and support in the complete denture. Discuss various factors affecting retention.
Or 
Define complete denture retention. Enumerate various factors of retention.
Or
Write in detail about retention in complete dentures.

Answer:

• Retention: That quality inherent in the prosthesis which resists the force of gravity, adhesiveness of foods, and the forces associated with the opening of the jaws
• Stability: The quality of the denture to be firm, steady & constant, to resist displacement by functional stresses & not to be subject to change of position when forces are applied
• Support: Resistance to vertical forces of mastication, occlusal forces & other forces applied in a direction toward the denture-bearing area

Factors Affecting Retention:

1. Anatomical factors:

• Size of denture bearing area:
  • The retention increases with an increase in the size of the denture-bearing area
  • Maxillary dentures are more retentive than mandibular as it has 24 cm² compared to that 14 cm²

• Quality of denture bearing area:
  • Displaceability of the tissues influences the retention of denture
  • Displacement of tissues during impression making
  • Result in tissue rebounding
  • Leads to loss of retention of dentures

2. Physiological factors:

• Saliva:
  • Thick & ropy saliva-loss of retention
  • Thin & watery saliva- compromised retention
  • Ptyalism- gagging
  • Xerostomia-Soreness & irritation

3. Physical factors:

• Adhesion:
  • The physical attraction of unlike molecules to one another
  • The amount of adhesion present is proportional to the denture base area
  • In xerostomia there is no adhesion

• Cohesion:
  • The physical attraction of like molecules for each other
  • Act within the film of saliva
  • Watery serous saliva- more retentive

• Interfacial surface tension:
  • The tension or resistance to separation possessed by the film of liquid between two well-adapted surfaces
  • Present within film of thin saliva
  • Useful in retention of the maxillary denture
  • Depends on the presence of air at the margins of liquid & solid contact

• • To attain maximum interfacial tension
  • Saliva should be thin
  • Perfect adaptation
  • Covering large denture area
  • Presence of good cohesive & adhesive forces

• Capillarity attraction:
  • That quality or state, because of surface tension causes elevation or depression of the surface of a liquid that is in contact with a solid
  • Presence of close adaptation between denture & the mucosa increases surface contact
  • Results in an increase in retention
  • Factors:
    1. Close adaptation
    2. Greater surface area
    3. A thin film of saliva
• Atmospheric pressure & peripheral seal:
  • It prevents air entry between the denture & soft tissue
  • To obtain it denture borders should rest on soft & resilient tissues
  • On application of forces, a vacuum has created that aid in retention
  • This is a natural suction of denture
  • It is directly proportional to the denture base area

4. Mechanical factors:

• Undercuts
• Retentive springs
• Magnetic forces
•  Denture adhesives
• Suction chambers & suction discs

5. Muscular factors:

• The balance should be between the forces acting from the buccal musculature & tongue

Question 4. Define complete denture impression. Discuss impression theories & techniques in treating complete denture patients.
Answer:

Complete Denture Impression:

A complete denture impression is a negative registration of the entire denture bearing, stabilizing & border seal areas present in the edentulous mouth.

Impression Theories:

1. Mucostatic Impression:

• By Richardson:
  • The impression is made with the oral mucous meme- brane & the jaws in a normal relaxed condition
  • The material of choice is impression plaster

2. Mucocompressive Impression:

• By Carole Jones:
  • Records oral tissues in a functional & displaced form
  • Dentures made by this technique tend to get displaced due to the tissue rebound at rest
  • This leads to residual ridge resorption

3. Selective Pressure Theory:

• By Boucher:
  • The impression is made to extend over as much denture-bearing area as possible without interfering with the limiting structures at function & rest
  • Forces are confined to the stress-bearing areas
  • Non-stress-bearing areas are relieved

Techniques of Impression:

1. Custom Tray Impression:

• Design a custom tray with a spacer
• It should be 2 mm short of the sulcus
• Border molding is done
• It results in recording the sulcus in dynamic function
• Spacer is scraped
• The impression is recorded by ZOE
• It results in recording the stress-bearing areas un- der pressure & non stress-bearing ares are relieved

2. Tray Compound:

• The impression made using tray impression compound •
• The impression is refined & trimmed
• The metal wire is attached to the tray compound to act as a handle
• Treat it as a custom tray
• Border moulding done
• Wash impression made over it

Question 5. Define impression. Discuss biological considerations for a maxillary impression.
Answer:

Complete Denture Impression:

A complete denture impression is a negative registration of the entire denture bearing, stabilizing & border seal areas present in the edentulous mouth.

Biological Considerations:

• The anatomy of the edentulous ridge in the maxilla is important in designing of complete denture
• Some parts of the ridge are capable of withstanding forces compared to others
• Thus it is considered before impression making

Limiting Structures:

• Labial frenum:
  • It is limiting structure of the Maxilla & Mandible
  • It is a fibrous band
  • Covered by mucous membrane
    • Extention: Labial aspect of residual ridge to lip
    • Maxillary: Passive due to absence of muscle fibres

Recorded In Impression:

Recorded in impression as a V shaped notch

• Requirement: Notch should be narrow & deep

• Labial vestibule:
  • That portion of the oral cavity which is bounded on one side by the teeth, gingival & alveolar ridge & on the other side by the lips & cheeks
  • Presence of orbicularis oris
  • It has an indirect displacing effect on the denture
•  Buccal frenum:
  • It separates the labial & buccal vestibule
  • Muscles attachments present: Levator anguli oris, orbicularis oris & buccinator
  • It needs greater clearance on the buccal flange of the denture

• Buccal vestibule:
  • It extends from buccal frenum to the hamular notch
  • Its size varies with: contraction of muscle, the position of mandible & amount of bone loss in maxilla
• Hamular notch:
  • Depression present between maxillary tuberosity & hamulus of medial pterygoid plate
  • Can be easily displaced to achieve posterior pala tal seal

Supporting Structures:

1. Primary Stress Bearing Areas:

•  Hard palate:
  • Trabeculae pattern of it perpendicular to direction of forces acting on it
  • Thus it acts as primary stress-bearing area

• Postero-lateral slopes of residual ridge:
  • Ridge rapidly resorbs following extraction of teeth
  • Resilient submucosa over it provides support to the denture

2. Secondary Stress Bearing Areas:

1. Rugae:
   • It is a secondary support area in maxilla
   • It is covered by thin mucosa

1. • Location:
     1. In the anterior region of the palatal mucosa
     2. At the angle of occlusal plane of the residual ridge
   • Significance: Important in speech
   • Precautions During Fabrication:
     1. Should not distort this area while impression making
     2. Metal denture should reproduce this area to make it comfortable
2. Maxillary tuberosity:
   1. Bulbous extension of residual alveolar ridge in 2nd 3rd molar region
   2. It is least likely to resorb

Relief Areas:

• Incisive papilla
• Location:
  • Midline behind central incisors
• Reason for Relieving:
  • It is exit point of nasopalatine nerves & vessels
  • If it is not relieved it compresses vessels & nerves
• Results:
  • Necrosis of the area
  • Paraesthesia of the anterior palate

1. Cuspid eminence:

• Bony elevation on residual alveolar ridge
• Location: between canine & 1st premolar

2. Mid-palatine raphe:

• Median suture area
• As it is covered by thin mucosa, it should be relieved

3. Fovea palatine:

• Coalescence of ducts of mucous glands
• Determines position of the posterior border of denture
• Relieved because of presence of ducts

Question 6. Describe mandibular anatomical structures.
Answer:

Limiting Structures:

• Labial frenum:
  • Active due to the presence of muscle incisive & orbicularis oris
  • It is fibrous band
  • Covered by mucous membrane
  • Extention: labial aspect of the residual ridge to lip
  • Recorded In Impression: Recorded in impression as a V-shaped notch
  • Requirement: Notch should be narrow & deep
    
• Labial vestibule:
  • That portion of oral cavity which is bounded on one side by the teeth, gingiva & alveolar ridge & on the other side by the lips & cheeks
  • Influences retention of dentures
• Buccal frenum:
  • Contains fibres of the buccinator
  • Prevent displacement of denture

Buccal vestibule:

• • Extends from buccal frenum to retromolar region
  • Bound by alveolar ridge & buccinator
  • Influenced by masseter
  • Notch is produced in denture flange called masseteric notch
• Lingual frenum:
  • Effects stability of denture high frenal attachment is called tongue tie

Alveololingual sulcus:

• Has 3 regions:

1. 1. Anterior region
      • From lingual frenum to pre-mylohyoid fossa
   2. Middle region
      • From pre-mylohyoid fossa to the distal part of mylohyoid ridge
   3. Posterior region
      • In the region of retro mylohyoid fossa
      • Determines lateral throat form

• Retromolar pad:
  • Forms posterior seal of denture
  • Location: Distal to the third molar
  • Consists of: Loose connective tissues, mucosal glands
  • Boundaries:
    1. Posteriorly: temporalis
    2. Lateral: buccinator
    3. Medial: Pterygomandibular raphe & superior constrictor

• Pterygomandibular raphe:
  • Extend: Hamular process to mylohyoid ridge
  • Muscles attached:
    • Postero- medially- superior constrictor
    • Antero-laterally-buccinator

Supporting Structures:

1. Buccal shelf area:

• Between buccal frenum & anterior border of the masseter
• Boundaries:
  • Medial: crest of the ridge
  • Distal: retromolar pad
  • Lateral: external oblique ridge
• Significance: Width increases with resorption of ridge
• Serves as primary stress bearing area

2. Residual alveolar ridge:

• Flat with concave denture-bearing surface
• On resorption inclines outward

Relief Areas:

 Mylohyoid ridge:

• Lies close to the inferior border of the mandible
• Covered with mucosa so should be relieved

3. Mental foramen:

• Location: Between 1st & 2nd premolar region
• Relieved as it may lead to paraesthesia

4. Genial tubercle:

• Location: anterior on the lingual side of body of the mandible
• Increases due to resorption

5. Torus mandibularis:

• Location: on lingual side near premolar region (b)
• Covered by a thin mucosa
• Relieved or surgically removed

Question 7. Discuss principles & objectives of making impressions for completely edentulous patients.
Or
What are the objectives of impression making
Answer:

Principles Of Impression Making:

1. Presence of healthy oral tissues
2. Inclusion of all supporting & limiting tissues
3. Borders within anatomical and physiological limitations
4. Border molding – physiological type
5. Space between material & tray
6. Not damaging the tissues
7. Application of selective pressure technique
8. Use of guiding mechanism
9. Use of dimensionally stable materials
10. Similarity to the form of dentures

Objectives Of Impression Making:

1. Retention:

“That quality inherent in the prosthesis which resists the force of gravity, adhesiveness of foods, and the forces associated with the opening of the jaws”.

• Factors:

1. 1. Anatomical factors:
      • Size of denture-bearing area
      • Quality of denture-bearing area
   2.  Physiological factors:
      • Saliva
   3.  Physical factors:
      • Adhesion
      • Cohesion
      • Interfacial surface tension
      • Capillary attraction
      • Atmospheric pressure
   4. Mechanical factors:
      • Undercuts
      • Retentive springs
      • Magnetic forces
      • Denture adhesives
      • Suction chambers & suction discs
   5. Muscular factors:

• • • The balance should be between the forces acting from the buccal musculature and tounge

2. Stability:

• The quality of the denture to be firm, steady & constant, to resist displacement by functional stresses & not to be subject to change of position when forces are applied
• It withstands horizontal forces
  • Factors:
    1. The vertical height of the residual ridge
    2. Quality of soft tissue
    3. Quality of impression
    4. Occlusal rims
    5. Teeth arrangement
    6. Shape of denture

3. Support:

• Resistance to vertical forces of mastication, occlusal forces & other forces applied in a direction toward the denture-bearing area
• The denture base should cover as much denture-bearing area as possible
• Results in the distribution of forces over wider area
• This leads to a reduction of force per unit area

Called Snow Shoe Effect:

4. Aesthetics:

• Thicker flange leads to fullness of the mouth

5. Preservation of Remaining Structures:

• Muller stated that the preservation of what remains is more important rather than to replace what is lost.
• Stress is provided over the stress-bearing area.
• Relief is provided over non-stress-bearing areas.
• Prevent damage to oral structures.
• Avoid overextension of dentures.

Question 8. Define stability & discuss factors affecting it.
Answer:

Stability:

• “The quality of denture to be firm, steady & constant, to resist displacement by functional stresses & not to be subject to change of position when forces are applied”.
• It withstands horizontal forces

Factors:

1. Vertical height of residual ridge:

• A ridge with an adequate height of ridge provides sufficient support
• Resorbed ridge causes loss of stability or reduced stability of the denture

2. Quality of soft tissue:

• Adequate submucosa is required for good stability
• Excessive submucosa results in poor stability

3. Quality of impression:

• The impression should be:
  • Accurate
  • Smooth surface
  • Devoid of voids
  • Not wrap on removal Dimensional stable

4. Occlusal plane:

• Should be parallel to ridge
• Should divide interarch space equally

5. Teeth arrangement:

• Teeth are arranged in a neutral zone
• That is balance is achieved in between tongue & buccal musculature

6. Shape of denture:

• Polished surface should resemble oral structures
• Should not interfere with the functioning of oral structures

Diagnosis And Treatment Planning

Diagnosis And Treatment Planning Important Notes

1. Thin mucosa is found over:

2. House’s classification of mental attitude:

3. Classification of the soft palate:

4. Classification of lateral throat form:

5. Classification of the tongue size:

Diagnosis And Treatment Planning Long Essays

Question 1. Discuss briefly the diagnosis & treatment planning for complete denture patients.
Answer:

Diagnosis: Includes:

1. Patient’s evaluation:

• Gait:
  • Different gate present in patients with neurological problems
  • This affects the adaptation of dentures
• Age:
  • Different aged people have different healing abilities
• Sex:
  • Women are more esthetic concerned than men
• Complexion:
  • Selecting the shade of teeth required

Read And Learn More: Prosthodontics Question And Answers

• Mental Attitude of Patient:
  • According to De Van” Meet the mind of the patient before meeting the mouth of the patient
• 4 types of patients are recognized:

1. 1. Class 1: philosophical
      • Easy-going, cooperative patients
   2. Class 2: Exacting
      • Dissatisfied with the previous denture
      • Difficult to satisfy them
   3. Class 3: Hysterical
      • Have a negative attitude toward the dentist
      • Poor prognosis
      • Difficult to manage
   4. Class 4: Indifferent
      • Uncooperative
      • Do not maintain the denture

2. Clinical history taking:

• Name:
  • To address a patient
  • To maintain the record
• Age:
  • For age-related diseases
• Sex:
  • For sex-related diseases
• Occupation:
  • To know the affordability of the treatment
• Location:
  • For further reference
  • For treatment planning
• Dental History:
  • To know the dental attitude of patient
• Medical History:
  • To know about any diseases that may affect the denture as well as the healing of tissues

3. Clinical examination:

• Extra Oral:
  • To evaluate any pathology
  • To determine the shape of teeth as compared to the profile of the patient

• • Determine vertical dimension: helps in deciding the size of teeth
  • Examine the lip & cheek fullness
• Intra Oral:
  • Examine the mucosa
  • Condition of the residual alveolar ridge
  • Arch length: to accommodate the teeth

• • Any pathology present
  • Gag reflex & palatal sensitivity
  • Undercuts present: Effect retention of the denture

• • Frenal attachment: Effect path of insertion

• • Tongue: Its size affects the stability of the denture

• • The floor of the mouth: For retention & stability of the denture

4. Radiographic examination:

• Bone Quality:
  • Examine any pathology
  • Bone contour

5. Evaluation of existing prosthesis:

• Need for repair
• Need for replacement

Treatment Planning Includes:

1. Adjunctive care:

• Elimination of Infection:
  • Treatment of ulcers
  • Removal of nonvital teeth
  • Elimination of periodontal problems
• Elimination of Pathosis:
  • Removal of any pathologies present
• Pre-Prosthetic Surgery:
  • Removal of flabby tissues
  • Removal of bony spicules
  • Frenectomy
  • Vestibuloplasty
  • Removal of tori
• Tissue Conditioning:
  • In case of tissue irritation due to dentures
  • Reline the existing denture with tissue conditioners

2. Prosthetic care:

• Patient Is Recently Edentulous:
  • Immediate denture
  • Interim denture
  • Implants
• Patient Already Edentulous:
  • Implants
  • Teeth selection
  • Soft tissue support

Diagnosis And Treatment Planning Short Answers

Question 1. Leon William’s classification.
Answer:

According to him, the facial form can be described among four types:

1. Ovoid
2. Tapering
3. Square
4. Combination

• The selection of teeth depends on the facial form
• For example Ovoid teeth for ovoid facial form

Question 2. The mental attitude of the patient.
Answer:

According to De Van, “meet the mind of the patient be- fore meeting the mouth of the patient”

4 types of patients are recognized:

1. Class 1: Philosophical
   • Easy-going, cooperative patients
2. Class 2: Exacting
   • Dissatisfied with the previous denture
   • Difficult to satisfy them
3. Class 3: Hysterical
   1. Have a negative attitude toward the dentist
   2. Poor prognosis
   3. Difficult to manage
4. Class 4: Indifferent
   1. Uncooperative
   2. Do not maintain the denture

Question 3. House’s palate classification
Answers:

It shows the relationship between the soft palate and hard palate  It is as follows

1. Class 1:
   1. Large and normal in form
   2. Has immovable tissue band 5-12 mm distal to a line drawn across the distal edge of tuberosities
2. Class 2:
   • Medium-sized and normal in form
   • Has immovable tissue band 3-5 mm distal to a line drawn across the distal edge of tuberosities
3. Class 3:
   • Accompanies small maxilla
   • Has soft tissue band 3-5 mm anterior to the line drawn across palate at the distal edge of tuberosities

Question 4. Classification of the soft palate.
Answer:

1. Class 1:
   • Horizontal line
   • Shows little muscular movement
   • Covers posterior palatal seal
   • Has flat palatal vault
2. Class 2:
   • The soft palate makes a 45° angle to the hard palate
   • Coverage to the posterior palatal seal is less
   • Has flat palatal vault
3. Class 3:
   • The soft palate makes a 70° angle to the hard palate
   • Coverage to the posterior palatal seal is minimum
   • Has V-shaped palatal vault

Question 5. Critical patients of House classification
Answer:

• They are very methodical, precise, and accurate making several demands
• They are comfortable when each procedure is ex- plained and discussed with them in detail
• They require extreme care, effort, and patience on the part of the dentist
• The intelligent and understanding category in this class can be best type of patient
• But for those lacking the same, extra time should be spent in education and treatment started only after an understanding is achieved

Question 6. House’s classification of the mental attitude of patients.
Answer:

 Complete Dentures Short Answers

Question 1. Parts of complete denture
Answer:

1. Denture base: The part of a denture that rests on the foundation tissues and to which teeth are attached
2. Denture flange: The part of a denture base that extends from the cervical ends of the teeth to the denture border
3. Denture borders: The margin of the denture base at the junction of the polished surface and impression surface
4. Denture teeth: They function to improve esthetics, phonetics, and mastication

Question 2. Steps in the fabrication of complete denture
Answer:

• Diagnosis and treatment planning
• Making diagnostic casts
• Mouth preparation
• Primary impression
• Primary cast
• Fabrication of custom trays
• Secondary impression
• Master cast
• Fabrication of occlusal rims
• Recording jaw relations
• Articulation
• Arrangement of artificial teeth
• Try in
• Processing of denture
• Insertion
• Post-insertion review and maintenance

Question 3. Effects of aging.
Answer:

• Young people have lighter teeth due to translucent enamel
• Old people have dark & opaque teeth due to secondary dentin formationShiny teeth in old people
• Teeth with a brownish tinge in older people Certain diseases are limited to certain ages
• Thus age can be used to rule out certain systemic conditions
• Age also determines the prognosis.

Question 4. Metal dentures.
Answer:

Indications of Metal dentures:

• Tooth supported dentures
• Reduced interocclusal space
• High occlusal forces
• Acrylic allergy

Advantages of Metal dentures:

• Improved retention & stability
• Improved thermal conductivity
• Comfortable for patients
• Easy to maintain

Read And Learn More: Prosthodontics Question And Answers

Disadvantages of Metal dentures:

• Difficult to reline
• Trimming is difficult
• Difficult to correct underextensions
• Fewer aesthetics

Question 5. Gagging
Answer:

The gag reflex is a normal, healthy defense mechanism to prevent foreign bodies from entering the trachea

Causes of Gagging:

• Over-extended denture borders
• Unstable occlusal conditions
• Systemic conditions
• Alcoholism, smoking

Features of Gagging:

• Causes displacement of denture
• Triggered by tactile stimulation of the soft palate, posterior part of the tongue & fauces

Site of Gagging:

• Posterior part of the maxillary denture
• Distolingual part of mandibular denture

Gagging Treatment:

• Correction of overextended dentures
• Correction of occlusal vertical dimensions and occlusal prematurities

Question 6. Angular cheilitis.
Answer:

Etiology:

• It occurs at the angle of the mouth among persons having deep commissural folds secondary to the overclosure of the mouth
• It can occur among persons with lip-licking habits, denture-wearing, or deficiency of riboflavin, vitamin B_12, and folic acid

Angular cheilitis Clinical Features:

• The infection starts due to the colonization of fungi in the skin folds following the deposition of saliva due to re-peated lip-licking
• Patients often have soreness, erythema, and fissuring at the corner of the mouth
• In some cases, it may extend over the adjacent skin sur- faces

Angular cheilitis Treatment:

• Lip balm
• Topical antiseptics
• Topical antifungal cream
• Topical steroid ointment
• Nutritional supplements

Question 7. Kelly’s combination syndrome.
Answer:

It was identified by Kelly in 1972 in patients wearing a maxillary complete denture opposing a mandibular distal extension prosthesis

Pathogenesis:

• It occurs in a sequential manner
• The patient tends to concentrate the occlusal load on  remaining natural teeth
• Results in more force acting on the anterior portion of the maxillary denture
• Increased resorption of the anterior part of the maxilla
• The labial flange will displace and irritate labial vestibule • Posteriorly there will be fibrous overgrowth in maxillary tuberosity
• The shift of occlusal plane posteriorly downwards pro- duces resorption in the mandibular distal extension denture-bearing area
• Mandible shifts anteriorly during occlusion
• There is
  • Decrease in vertical dimension at occlusion
  • Decrease in retention and stability of a denture
  • Disocclusion of lower anterior
  • Reduced periodontal support of anterior teeth

Question 8. Infection control
Answer:

Methods:

• Immunization:
  • Vaccination for Hepatitis B for all dental personnel
• Personal barrier:
  • Hand washing before gloving & after degloving
  • Gloves Protect against contamination
  • Changed between patients & for the same patient is torn or worn out
    • Face mask:
      1. Protects from inhalation of aerosols
      2. Prevents spatter from patient’s mouth
      3. Prevents droplets from contaminated solution
      4. Protective clothing
      5. Gown with long sleeves, high neck & long knee length
    • Eyewear:
      1. Prevention of bacterial/viral contact
• Surgical asepsis:
  • Preparation of surgical site
  • Draping the patient
  • Isolation
• Surface asepsis:
  • Sterilization of instruments
  • Use of disposable instruments
• Disposal of waste: Methods
  • Incineration
  • Burial in a landfill
  • |Sterilization

Question 9. Hypermobile ridge tissue.
Answer:

Hypermobile ridge tissue Cause:

• Due to excessive residual ridge resorption Management:
• Small tissues which do not interfere with tissue functioning:
  • Left untreated: Impression is made using the mucositis technique
  • Large tissues: removed surgically

Question 10. Polished surface.
Answer:

• It is defined as that portion of a surface of a denture that extends in an occlusal direction from the border of the denture and includes the palatal surfaces
• It is the part of the denture base which is usually polished and it includes the buccal and lingual surfaces of the teeth
• It refers to the external surfaces of the lingual, buccal, and labial flanges and the external palatal surface of the denture
• It should be well polished and smooth to avoid the collection of food debris
• It should be harmonious with the oral structures
• They should not interfere with the action of oral mus- culture

Question 11. Denture irritation hyperplasia.
Answer:

The hyperplastic reaction of mucosa over the borders of the denture

Denture irritation hyperplasia Cause:

• Trauma due to unstable dentures

Denture irritation hyperplasia Features:

• Deep ulceration
• Fissuring
• Inflammation

Denture irritation hyperplasia Management:

• Surgical excision
• Correction of dentures

Question 12. Xerostomia.
Answer:

It refers to a subjective sensation of a dry mouth, but not always, associated with salivary hypofunction

Etiology:

1. Developmental:
   1. Salivary gland aplasia
2. Water/metabolic loss:
   • Impaired fluid intake
   • Hemorrhage
   • Vomiting/diarrhea
3. Latrogenic:
   • Medications:
     • Antihistamines: Diphenhydramine
     • Decongestants: Pseudoephedrine
     • Antidepressants: Amitriptyline
     • Antipsychotic: Haloperidol
     • Antihypertensive: Methyldopa, CCB
     • Anticholinergic: Atropine
4. Radiation therapy of head & neck:
   1. Both stimulated & unstimulated salivary flow decreases with increasing radiotherapy.
   2. Systemic Diseases:
      • Sjogren’s syndrome
      • Diabetes mellitus
      • Diabetes insipidus
      • HIV infections
      • Psychological disorders.
      • Graft-versus-host disease
5. Local factors:
   • Decreased mastication.
   • Smoking
   • Mouth breathing

Question 13. Functions of saliva.
Answer: 

Question 14. Combination syndrome.
Answer:

It was identified by Kelly in 1972 in patients wearing a maxillary complete denture opposing a mandibular distal extension prosthesis

Pathogenesis:

• It occurs in a sequential manner
• The patient tends to concentrate the occlusal load on re- remaining natural teeth Results in more force acting on the anterior portion of the maxillary denture
• Increased resorption of the anterior part of the maxilla
• The labial flange will displace and irritate the labial vestibule Posteriorly there will be fibrous overgrowth in the maxillary tuberosity
• The shift of occlusal plane posteriorly downwards pro- duces resorption in the mandibular distal extension denture-bearing area
• Mandible shifts anteriorly during occlusion
• There is
• Decrease in vertical dimension at occlusion
• Decrease in retention and stability of the denture
• Disocclusion of lower anterior
• Reduced periodontal support of anterior teeth

Introduction To Complete Dentures

Definitions Of Complete Dentures

1. Complete denture: A removable dental prosthesis that replaces the entire dentition and associated structures of the Maxilla or mandible.
2. Residual ridge resorption:
   • It is alveolar remodeling that occurs due to changes in the functional stimulus of bone.
   • It is diminishing the quality and quantity of the residual ridge after teeth are removed.

Classification Of Complete Dentures

1. Progression of residual ridge resorption by Atwood.

1. Order 1: Pre extraction
2. Order 2: Post extraction
3. Order 3: High, well-rounded
4. Order 4: Knife edged
5. Order 5: Low, well-rounded
6. Order 6: Depressed.

Complete Dentures Important Notes

• Surfaces of complete denture:
  • Occlusal surface
  • Impression surface
  • Polished surface
• Parts of complete denture:
  • Denture base
  • Denture flange
  • Denture borders
  • Denture teeth
• Objectives of complete denture:
  • Should be compatible with the surrounding oral environment
  • Should restore oral function
  • Should be in harmony with the function of speech respiration and deglutition
  • Should be aesthetically acceptable
  • Should preserve the remaining oral tissues.
• Direction of residual ridge resorption:
  • Maxillary ridge – Upward and lingual direction
  • Mandibular anterior ridge  – Downward and lingual direction
  • Mandibular posterior ridge – Downward and buccal direction.
• Angular stomatitis (also known as perleche or angular cheilosis) occurs commonly due to:
  • Decreased VDO or
  • Deficiency of ‘Riboflavin or Thiamine’ or
  • Due to Candida infection.
•  Denture stomatitis:
  • It refers to pathological reactions of the denture-bearing palatal mucosa
  • Types:
    • Type 1 – Localized inflammation
    • Type 2 – Generalized inflammation
    • Type 3 – Granular type
• Predisposing factors for Candida-associated denture stomatitis:
  • Aging
  • Malnutrition
  • Immunosuppression
  • Radiation therapy
  • Diabetes
  • Antibiotics

8. Epulis fissuratum:

• It is soft tissue reaction that appears in the sulcular area due to over-extension of the denture flanges
• It is treated by shortening and smoothening the denture border

9. Papillary hyperplasia:

• It results from Candida infection and improper relief of the palatal area in the denture
• Small lesions are treated by curettage
• Large lesions are treated by split-thickness suprapenosteal excision

Complete Dentures Short Essays

Question 1. Denture induced hyperplasia
Answer:

The hyperplastic reaction of mucosa over the borders of the denture

Cause of hyperplasia:

• Trauma due to unstable dentures:

Features of hyperplasia:

• Deep ulceration
• Fissuring
• Inflammation

Management of hyperplasia:

• Surgical excision
• Correction of dentures

Question 2. Epulis fissuratum
Answer:

It is a soft tissue reaction that appears in the sulcular region due to overextension of the denture flange.

Read And Learn More: Prosthodontics Question And Answers

Symptoms of Epulis fissuratum:

Single or numerous lesions showing flaps of hyperplastic connective tissue

• Deep ulceration
• Fissuring
• Inflammation at the depth of the sulcus

Treatment of Epulis fissuratum:

• Excision of tissues
• Shortening and smoothening of denture border

Question  3. Indications and contra indications of complete denture Answer:

complete denture Indications:

• Presence of adequate edentulous ridges with sufficient vertical space
• Serious loss of masticatory functions
• Impairment of aesthetics, speech, and psychological well being
• In patients where remaining teeth cannot be retained

Contraindications:

• An edentulous patient who has not worn dentures in many years
• Unmanageable mechanical problems
• Patient with no salivary function due to radiation
• Altered systemic health
• Allergic to acrylic resinPatient with severe or total paralysis of motor nerves of tongue, cheeks, lips, or floor of the mouth
• Excessive loss of maxilla or mandible
• Large maxillary or mandibular tori.

Question 4. Residual ridge resorption.
Answer:

• It is alveolar remodeling that occurs due to change in the functional stimulus of bone tissue
• It is a chronic progressive change in the bone structure, which results in severe impairment in the fit & function of the prosthesis

Cause of Residual ridge:

• Excessive forces over non stress-bearing areas cause activation of osteoclasts

Clinical Features of Residual ridge:

• Decreased depth & width of sulcular
• Decreased vertical dimension at occlusion
• Reduced lower facial height
• Anterior rotation of mandible
• Increase in relative prognathism
• Increased mandibular arch
• Decreased maxillary arch
• Effects support, stability & retention of dentures

Treatment of Residual ridge:

• Ridge augmentation to increase the height of the ridge
• Vestibuloplasty to increase the depth of the sulcus

Question 5. Burning mouth syndrome
Answer:

Burning sensation in the structures in contact with the dentures without any visible change in the mucosa

Features of mouth syndrome:

• Pain in the morning
• Dry mouth
• Persistent altered taste
•  Generalized symptoms

Etiology of mouth syndrome:

• Irritation by ill-fitting dentures
• Constant masticatory activity
• Excessive friction on the mucosa Candidal infection
• Nutritional deficiency
• Xerostomia
• Medication

Management of mouth syndrome:

• Counseling
• Repair of ill-fitted denture
• If there is no denture deficiencies then it requires psychological counseling
• An implant-supported denture fabrication may be carried out

Question 6. Denture stomatitis
Or
Denture sore mouth
Answer:

It is the pathological reaction of the palatal portion of the denture-bearing mucosa

Types of Denture stomatitis:

1. Type I: Localized simple infection
2. TypeII: Erythematous type
3. Type III: Granular type

Etiology of Denture stomatitis:

• Candida albicans

Predisposing Factors of Denture stomatitis:

1. Local factors:
   • Dentures
   • Xerostomia
   • High carbohydrate diet
   • Use of broad-spectrum antibiotics
   • Smoking
2. Systemic factors:
   • Old age
   • Diabetes mellitus
   • Nutritional deficiency
   • Immune defect
   • Malignancy

Treatment of Denture stomatitis:

• Good oral hygiene
• Keep the denture as clean as possible
• Avoid wearing dentures at night
• Clean the dentures by brushing, soaking, and then brushing again
• If the denture contains metal work do not use anything that contains bleach.

Management of Denture stomatitis:

• 0.2-2% chlorhexidine
• Removal & cleaning of dentures after every meal
• Avoid night wearing of dentures
• Polishing of denture
• Administration of anti-fungal drugs
• Surgically: Elimination of crypts, by cryosurgery

Complete Denture Viva Voce

1. Surfaces of complete dentures are described by Fish.
2. The Fit of the denture depends on the accuracy of the impression surface.
3. Occlusal surface aids in mastication
4. The polished surface is the external surface of the complete denture
5. Result of residual ridge resorption
   • Prognathic appearance
   • Wide mandible, narrow maxilla
   • Concave profile
6. The ratio of anterior maxillary residual ridge resorption to anterior mandibular residual ridge resorption is 1:4.
7. Factors affecting residual ridge resorption (RRR)
   • RRR – directly proportional to bone resorption fac- tor/bone formation factor
   • RRR directly proportional to the pressure/ damping factor
   • RRR directly proportional to the anatomic factor
8. The cause of Epulls fissuratum is over-extension of the denture flange
9. Treatment of Epulis fissuratum is shortening and smoothening the denture
10. The cause of papillary hyperplasia is a candidal infection
11.  Treatment of papillary hyperplasia
    • Small lesions curettage
    • Large lesions split thickness subperiosteal excl sion
12. A diffuse erythematous zone under denture covered area is a sign of denture stomatitis
13. Cause of flabby ridge excessive load on the residual ridge
14.  Cause of traumatic ulcer
    •  Overextended flanges
    • Occlusal imbalance
15. Burning mouth syndrome is common in females older than 50 years.