Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

pontics in FPD (prosthodontics)


Published on

fixed partial dentures in prosthodontics

Published in: Health & Medicine
  • Be the first to comment

pontics in FPD (prosthodontics)

  2. 2. INTRODUCTION • Pontics are the artificial teeth of a fixed partial denture that replaces missing natural teeth,restoring function and appearance. • Proper preparation includes a careful analysis of critical dimension of edentulous area; mesiodistal width; occlusocervical disatnce; buccolingual siameter and location of residual ridge.
  4. 4. PRE-TREATMENT ASSESMENT PONTIC SPACE: One function of the fpd is to prevent tilting or drifting of the adjacent teeth into the edentulous space. If such movement has already occurred, the space available for the pontic may be reduced and its fabrication complicated. Overly small pontics are undesirable because they trap food and are difficult to clean.
  5. 5. Orthodontic repositioning, modification of abutments with complete coverage retainers can be made.
  6. 6. RESIDUAL RIDGE CONTOUR An ideally shaped ridge has smooth, regular surface of attached gingiva, which facilitates maintainance of a plaque-free environment. Should have sufficient height to allow placement of pontic such that it apperas to emerge out from the ridge (mimics appearance of neighbouring teeth).  Loss of residual ridge contour may lead to unesthetic open gingival embrasures (black traingles). This leads to food lodgement and saliva percolation.
  7. 7. Siebert has classified residual ridge deformities into: Class I: facio-lingual loss of tissue width with normal ridge height. Class II: loss of ridge height with normal ridge width. Class III: a combination of loss in both dimension.
  8. 8. surgical modification Although pre-prosthetic surgery like ridge augmentation with a hard tissue graft may be done, it is not always indicated unless the edentulous site is to receive an implant.
  9. 9. PONTIC CLASSIFICATION: Mucosal contact No mucosal contact - Ridge lap - Sanitary (hygenic) - Modified ridge lap - Modified sanitary (hygenic) - Ovate - Conical
  10. 10. Design location Indication Contra- indication Materials 1. sanitary/ hygenic Posterior mandible Non- esthetic zone; Impaired oral hygeine Minimal vertical dimension All metal 2. conical Molars without esthetic requirement Posterior areas with minimal esthetic requirement Poor oral hygeine All metal Metal-ceramic All resin
  11. 11. Design location Indication Contra- indication Materials 3. Modified ridge lap High esthetic (anteriors, premolars & sometimes molars) Esthetic concern Minimal esthetic concern Metal-ceramic All resin 4. Ovate Maxillary incisors, cuspids & premolars Desire for optimal esthetics ; High smile line Unwilling ness for surgery Metal-ceramic All resin
  12. 12. BIOLOGIC CONSIDERATIONS Aims at maintainace and preservation of residual ridge, abutments, opposing teeth and supporting tissues. Factors: 1. Ridge contact 2. Oral hygeine considerations 3. Pontic material 4. Occlusal forces
  13. 13. Ridge contact Pressure free contact between the tissue and pontic is indicated to prevent ulceration &inflamation of soft tissues. If any blanching of tissues occurs during try-in, pressure areas should be identified using disclosing medium and pontic recontoured until tissue contact is entirely passive.
  14. 14. Oral hygeine considerations: Chief cause of ridge irritation toxins released from microbial plaque accumulates between gingival surface of pontic and residual ridge calculus formation and tissue irritation. Unlike RPD, FPD cannot be removed for cleansing. Normally where tissue contact occurs,gingival area of pontic is inaccessible. Devices such as proxy brushes, superfloss may be used. If pontic has a concavity or depression in its gingival surface, there will be palque accumulation which leads to inflamation. Therefore FPD should be checked & corrected before cementation.
  15. 15. Pontic material Should provide Good esthetics where needed Biocompatibility Rigidity and strength to withstand occlusal forces Longevity FPD should be made as rigid as possible, because any flexure during mastication or parafunction may caus epressure on gingiva and fracture of veneering material. Occlusal contacts should not occur at metal-porcelain junctions. Pontic material should have ability to resist plaque accumulation(surface roughness should be less) Therefore, gold glazed porcelain ceramic
  16. 16. Occlusal forces To withstand occlusal forces, it has been suggested to reduce the bucco-lingual dimension of the pontic by 30% But in case of parafunctional habits or accidental biting on a hard object, this may not be efficient. Infact, it may impede harmonious and stable occlusal relationship Hence, normal pontic width atleast at the occlusal third is recommended Exception-when ridge is collapsed bucco-lingually
  17. 17. MECHANICAL CONSIDERATIONS Factors that lead to fracture of prosthesis or displacement of retainers: 1. improper choice of material 2. poor frame work design 3. poor tooth preparation 4. poor occlusion
  18. 18. When metal-ceramic pontics are chosen, extending porcelain onto occlusal surfaces to achieve better esthetics should be carefully evaluated. Porcelain may also abrade the opposing dentition if occlusal contacts are on enamel or dentin.
  19. 19. ESTHETIC CONSIDERATION • Priority of the patient. • Gingival interface: -an esthetically successful pontic will replicate the form, contour, incisal edge, gingival and incisal embrassures and color of adjacent tooth. -attention should be paid to the contour of labial surface as it approaches the pontic-tissue junction to achieve a “natural” appearance.
  20. 20. • Modified ridge lap is recommended for most anterior teeth. It compensates for lost bucco-lingual width in the ridge by overlapping the existent ridge. • When esthetics is of utmost concern, yhe ovate pontic used in conjunction with alveolar preservation or soft tissue augmentation can provide indistinguishable appearance.
  21. 21. Incisogingival length Obtaining a correctly sized pontic simply by duplication of the original tooth is not possible. Ridge resorption will make the tooth look too long in cervical region. However an abnormal labio-lingual position is not so obvious. Hence it is used to improve appearance by recontouring giongival half of labial surface. Another solution is to shape the pontic to stimulate a normal crown and root with emphasis on CEJ Or by using pink acrylic
  22. 22. Mesio-distal width: Frequently space available for the pontic is less than the contra-lateral tooth This is due to uncontrolled toth movement which took place when the tooth was lost and not replaced. If possible, such discrepancy should be corrected by orthodontic repositioning The space discrepancy can also be corrected by altering the shape of proximal areas (by duplicating the mesial half of the tooth and adjusting the size of the distal half)
  23. 23. PONTIC FABRICATION Materials available: advgs disadvgs indications Contra- indications Metal-ceramic Esthetics Biocompatible Weaker than all metal pontics Most situations Long span with high stress All-metal Strength Simple procedure Non-esthetic Mandibular molars Esp under high stress Where esthetics is important Fibre reinforced resin Conservative Esthetic Ease of repair Limited to short span uniots High esthetic concern Long span fpd’s facings Rarely used-of historic interest only