support for complete denture fabrication

1. 1
SUPPORT IN COMPLETE
DENTURE PROSTHESIS
Presented by
-------------------------------------------------------
Dr PRATIK HODAR (Pg 1st yr)
Guided by -
Dr P. Balaji Raman
Dr SashiPurna
Dr Durga raju
Dr Ashwin Aidasani
Dr Abhay Narayane
DR. HSRSM DENTAL COLLEGE AND HOSPITAL, HINGOLI
DEPARTMENT OF PROSTHODONTICS

2.  Introduction
 Definition
 Types
 Importance
 Anatomical consideration
1. Oral mucous membrane
2. Denture supporting area
 Factors affecting support
 Conclusion
 Refrence
2

3.  Dentist must base their technique on
understanding of the biological aspect of the
relationship between the denture base and
supporting tissue.
3

4.  THE FOUNDATION AREA ON WHICH A DENTAL
PROSTHESIS RESTS.(GPT 8TH EDITION)
 SUPPORT IS THAT QUALITY WHICH RESISTS
VERTICAL MOVEMENT OR DISPLACEMENT OF THE
DENTURE TOWARD THE BASAL SEAT.
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5. › Initial support –
 Through impression procedures
 Functional loading of supporting tissues
› Long term
 Directing occlusal forces towards resistant tissues
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6.  Reduce tissue ward movement of denture.
 Improve masticatory function.
 Maintain occlusal relationship.
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IMPORTANCE:-

7.  Oral mucous membrane:
1. Definition.
2. Classification .
3. Importance for support.
 Denture supporting areas:
1. Maxillarysupporting area.
2. Mandibular supporting area.
3. Anatomical landmarks.
4. Bone.
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8.  The oral cavity is lined by soft tissue known as
mucous membrane.
 Mucous membrane composed of 2 layers,
- MUCOSA : It is made of stratified squamous
epithelium & Connective tissue called Lamina
Propria.
- SUBMUCOSA : It is formed by connective
tissue. It may contain glands , fatty tisue,
muscle, transmitting blood vessels and nerve.
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10. 10
CLASSIFICATION OF ORAL
MUCOSA
MASTICATORY
MUCOSA.
Example- Gingiva, Hard
Palate,
LINING
MUCOSA.
Example- Lip, Cheek & All
other parts of the oral cavity
except the Anterior 2/3rd of
the Dorsal Surface of the
tongue
SPECIALIZE
D MUCOSA.
Example- Anterior 2/3rd of the
Dorsal Surface of the Tongue
(Courtesy : Orban’s: text book of oral histology 14th
edition)

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12.  COVERS :- Crest of the ridge, hard palate and the
residual attached gingiva to the supporting bone.
 It has well defined keratinized layer.
 Submucosa is not well developed in masticatory
Mucosa.
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13.  COVERS:- Dorsal surface of tongue.
 Keratinized in nature.
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14.  COVERS :- Vestibular spaces, alveolingual sulcus, soft
palate, ventral surface of tongue, unattached gingiva
found on slopes of residual ridge.
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15.  Gives cushioning effect
 Medium thickness and uniform resiliency favors
prognosis.
 Thick mucous membrane- retention is
compromised more than stability
 Thin and atrophic membrane gets damaged and
ulcerated.
 Inflamed mucosa :
1. Before denture insertion- elimination and treat for
inflammation
2. After denture insertion- ask patient to stop wearing
denture 5-6 days till it gets normal.
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16.  Yemm in 1972
-Stress can induce increase activity of masseter and
temporalis muscles in denture wearers, which in turn
cause tooth contact and eventually soreness of the
mucosal tissues.
 Lindan in 1961
-0.13 gm/ mm2 will displace soft tissues by 95%
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17. 17

18. Primary stress bearing areas
 Hard palate
 Maxillary tuberosity
 Secondary stress bearing area
 Residual alveolar ridge
 Rugae
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(Courtesy : Zarb, Hobkirk : text book of
prosthodontic treatment for edentulous patient 13th
edition)

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20.  Use for maxillary denture support.
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21. • Large Tuberosity-
• provides fine bearing surfaces.
• But, have problems also –
1. Encroachment on the inter-ridge distance;
2. large or opposing undercuts
Fibrous Tuberosity-
Surgically reduced.
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22. 22

23.  They are raised area of dense connective
tissue radiating from the median suture in
anterior 1/3rd of palate
 Resists anterior displacement of denture
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24. 24

25. 25

26. 26

27. MANDIBULAR
 primary stress bearing areas
 Buccal shelf
 Retro molar pad
 Secondary
 Residual alveolar ridge
(Courtesy : Zarb, Hobkirk : text book of prosthodontic
treatment for edentulous patient 13th edition)
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28.  Borders:
1. Externally- external oblique lines
2. Internally- residual ridge
3. Anterior- buccal frenum
4. Posteriorly- retro molar pad
 Parallel to the floor
 Forces directed right angle
 Very dense trabeculation
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29. 29

30.  Pear shape
 One constant and unchanged structure
 Mass of soft structure
 Contain : mucous gland, temporal tendon,
pterygomandibular raphae, buccinator,
superior constricting muscle.
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31. 31

32. 32

33. 33

34.  For maxilla: abundant keratinized attached tissue.
Square shaped arch, moderate palatal vault,
absence of undercut, well defines hamular notch
 For mandible: well defined retromolar pad blunt
mylohyoid ridge low frenum attachment.
 Problem with ridge
1. Sharp and spiny
2. Crestal bone irregularities
3. Sever resoption and mental foramina
4. Tori
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35. 35

36. 36

37. 37

38.  “My gums have been shrunken”
 SIX ORDERS OF MANDIBULAR ANTERIOR
RESIDUAL RIDGE FORM by Attwood (1963)-
1. Order I-Pre extraction.
2. Order II-Post extraction.
3. Order III- High, well rounded.
4. Order IV-Knife edge.
5. Order V- Low, well rounded.
6. Order VI- depressed.
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39. 39

40.  Consequences: ----
Compromised support
1. -Movement of dentures
2. -Instability of prosthesis
 Prevention
-Minimizing the forces transmitted to supporting
tissues
-Decrease the movement of prosthesis
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41. 41
(Lekholm & zarb 1985)

42.  Gordan GS Genent HK after the age of 40xyrs, the
skeleton decreases, so that by age of 65 approximately
1/3rd of bone minerals are lost.
 SOBOLIK(1960)writes that constant pressure will cause
bone resorption, but intermittent pressure favours bone
formation.
 PENDLETION(1951)has said that pressure applied to
bone in an abnormal direction will result in resorption.
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REVIEW OF LITERATURE

43.  STAHL(1948) showed that ridge resorption increase
with the severity of diabetes.
 PERSON(1957) noted that during a rapid and intense
loss of alveolar bone in diabetic, the long bone and
pelvis remained intact.
 NORDIN(1960) Osteoporosis is generalized condition of
bone in which the volume of bone in skeleton is
reduced.
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44. 44

45. 45
ACCORDING TO HISTOLOGY
MATURE
BONE
COMPACT /CORTICAL
BONE
SPONGY/CANCELLOUS
BONE
IMMATURE
BONE
WOVEN BONE
(Courtesy : Orban’s text book of oral histology 13th edition)

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47.  Bone cells- A. Osteoblasts,
B. Osteocytes,
C. Osteoclasts
D.Stem cells or
Osteochondral Progenitor cells
 Woven bone – Collagen fibers randomly
oriented.
 Lamellar bone- Mature bone in sheets.
 Compact bone- Trabaeculae.
 Cortical bone- Dense.
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48.  It is in continuous flux throughout life. (Frost ; enlow)
 ADULTS : Formation= Resorption
 SENILITY : Formation< Resorption
 Placement of denture after extraction require 6 weeks/ 2
months.
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49.  WOLF LAW- Change in form follows a change in
function owing alteration of the internal architecture and
external conformation of bone.
 NEUFELD REPORTED: In some specimens studied,
the trabecular pattern was arranged in such a way that it
indicated that there was some adaptation of structure of
bone to the bone to presence of an appliance in region
near the superior space of alveolar process.
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50.  1] Its original size and consistency;
 2] the persons general health;
 3] forces developed by the surrounding
musculature;
 4] the severity the location of periodontal disease
(Hausman ; Hedegard)
 5] forces accruing from the wearing of dental
prosthesis;
 6] surgery at the time of removal of the tooth;
 7] the relative length of the time different parts of
the jaws has been edentulous.
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51.  Include:- all denture bearing area.
 Exclude:- all relief area.
 Snow shoe effect
 Watt 1961
-mean denture bearing area
maxilla (22.96 cm2)
mandible (12.25 cm2)
51

52.  Large surface area
 Nature of supporting area
 Impression procedure
 Accuracy of fit
 Direct bone anchorage
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53. 1] Recording the tissue impression at their rest position.
2] Decreasing the size of food table.
3] Developing an occlusion that eliminates, as much as
possible, horizontal forces and those that produce torque.
4] Extending the denture base for maximum coverage
within physiologic limit.
5] Biting with the knife and fork, that is, placing small
masses of food over the posterior tooth where the
supporting bone is best suited to resist force.
6] Removing the denture for at least 8 of every 24 hours for
tissue to rest.
53

54.  Selection of regions that should provide
primary and secondary support depends on
anatomic variation unique to each patient.
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55.  Orbans: Oral histology and embryology 14th edition
 Charles heartwell: syallabus of complet denture 4th
edition.
 Jhon sharry : Complet denture prosthodontic 3rd edition.
 Zarb and Bolender : prosthodontic treatment for
edentulos patient 12th edition.
 Zarb and Bolender : prosthodontic treatment for
edentulos patient 13th edition.
55

56.  Sheldon wrinkler : essentials of complete denture
prosthodontics 3rd edition.
 Karl mish : Contemporary implant dentistry 3rd edition.
 Glossary of prosthodontics terms 8th edition.
 A contemporary review of the factors involved in
complete dentures Part III: Support T. E. Jacobson & A.
J. Krol JPD 1983;49:306-313.
 A review of residual ridge resorption and bone density:
Esa klemetti
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