Pontics in Fixed Partial Denture
- 1. PONTICS IN FIXED PARTIAL DENTURE PRESENTED BY: RAJAT HEGDE
- 2. CONTENTS Introduction Definition Ideal requirements of a pontic Functions of a pontic Pontic design General design consideration for a pontic Classification of pontics Pontic Selection Types of pontics Special pontics Pontic modification Pontic fabrication Post-insertion hygiene Conclusion
- 3. INTRODUCTION • The term pontic is derived from Latin word ‘Pons’, meaning bridge. • What is a Pontic in FPD…? Pontic is that part of FPD that replaces lost natural tooth, restores its functions and occupies the space of the missing tooth/teeth.
- 4. PONTIC Definition: • Pontic is defined as an artificial tooth on a fixed partial denture that replaces a missing tooth, restores its functions and usually fills the space previously filled by a natural crown” -GPT • Standard sized teeth cannot be used as a pontic in FPD. • Hence, the pontic is fabricated for that patient to fulfill its requirements.
- 5. IDEAL REQUIREMENTS • It should restore the function of the tooth it replaces. • It should provide good esthetics. • It should be comfortable to the patient. • It should be biocompatible - should not impinge on the tissues or produce any kind of tissue reaction. • It should be easy to clean and maintain - to permit effective oral hygiene. • It should preserve the underlining mucosa (from ulcerations) and bone (from resorption of residual alveolar ridge).
- 6. FUNCTIONS OF PONTIC 1. Mastication 2. Speech 3. Esthetics 4. Maintaining tooth relationship 5. Psychological
- 7. PONTIC DESIGN • The success of an FPD depends on the proper design of the pontic. • If the pontic is not designed to restore function and esthetics, the chances of failure is increased. Factors affecting the design of pontic : 1. Space available for the placement of the pontic. 2. The contour of the residual alveolar ridge. 3. Amount of occlusal load that is anticipated for that patient.
- 8. 1. Edentulous space: • The space created due to the loss of teeth is usually sufficient for the fabrication of a good pontic. • Long period of edentulousness may cause the adjacent teeth to tilt or drift towards this space. • For cases with deficient contact space the following procedure can be done: i. Orthodontic movement of adjacent teeth. ii. Placement of modified full coverage retainers. 2. Residual ridge contour: • During the treatment planning the diagnostic cast should be thoroughly examined. • The contour of the ridge and texture of the soft tissue should be observed during intra oral examination • Smooth rounded ridge - best for the placement of a pontic. • In cases of overhanging hyperplastic tissues, surgical excision of the tissues is carried out. • Cases with severe residual alveolar ridge resorption should be treated with ridge augmentation, tissue grafts...
- 9. Occlusal load on the pontic: • According to Stein, the basic requirement of pontic is that it should be able to restore proper function. • The amount of occlusal load determines the selection of material as well as design of the FPD. • The most critical consideration in design of pontic is functional relationship of the cusps of pontic and opposing teeth.
- 10. GENERAL DESIGN CONSIDERATIONS FOR A PONTIC
- 11. Gingival Surface : • The material used and the tissue contact affects the success of restoration. • Material of choice – highly glazed porcelain. • The pontic should not be designed to pressurise the alveolar mucosa as it may ulcerate. • Tissue contact should be minimal. • The factors affecting the pontic-ridge relationship considered while designing an FPD are: 1. Periapical pathology 2. Periodontal disease 3. Trauma from occlusion 4. Age of patient 5. Healing efficiency
- 12. Occlusal Surface : • Size of the occlusal table can be reduced – decreases amount of force centred on abutment. • The functional cusps of occlusal surface of the pontic shouldn’t be reduced – to preserve stable vertical dimension. • In maxillary teeth – buccal cusps provide esthetics. • In lower teeth – lingual cusp protect the tongue.
- 13. Proximal Surface : • Vertical clearance should be sufficient to permit physiologic contour of the pontic and allow space for the interproximal tissue. • Interproximal embrasures should be left open to permit easy cleaning. • The sizes of the maxillary interproximal embrasures should be reduced for the sake of esthetic. But sufficient space should be given to avoid impingement to the interdental papilla. • Wider embrasures are provided for posterior teeth for the better cleansing and the mandibular molars are provided with the large embrasures.
- 14. Buccal And Lingual Surfaces: • The facial surface should be designed with the aesthetic as the primary concern. It should resemble the adjacent teeth. • The lingual surface is designed with hygiene as the primary concern. • The embrasures are wider lingually then facially. • The lingual surface should be designed such that it is similar to an adjacent teeth from the cusp tip till the height of contour, then it should recede sharply and concavely from the height of contour towards the facial surface to form a pinpoint contact on the labial surface of the residual alveolar ridge.
- 15. DESIGN CONSIDERATION FOR POSTERIOR AND ANTERIOR PONTIC Posterior Pontic • All the surfaces should be convex, smooth and properly finished. • Contact with the buccal slope of the ridge should be minimal and pressure free. • The occlusion table should be in harmony with the occlusion of all the other teeth. • The overall length of the buccal surface should be equal to that of the adjacent abutments or pontics. Anterior Pontic • All surfaces should be convex, smooth and properly finished • Contact with the labial slope of the bridge should be minimal (pinpoint) and pressure free (modified Ridge lap design). • A larger contact with the ridge is provided for a natural look. If a pinpoint contact is given for a case with the ridge resorption, unaesthetic black spaces may become visible. • Lingual contours should be in harmony with that of the adjacent teeth
- 16. CLASSIFICATION OF PONTICS According to Shillingburg: I Based on Shape: • Saddle/Ridge lap pontic • Modified ridge lap • Hygienic/sanitary pontic • Ovate pontic • Conical pontic II Based on Material Used: • Metal ceramic pontic • Metal and resin veneered pontic • Cast metal • All ceramic pontic
- 17. III Pre-fabricated Pontics: 1. Trupontic 2. Interchangeable facing 3. Harmony pontic 4. Porcelain fused to metal facing 5. Pin facing 6. Reverse pin facing
- 18. According to Rosensteil: I Pontics that Contact Oral Mucosa: • Ridge lap • Modified ridge lap • Ovate • Conical II Those that Do Not Contact Oral Mucosa: • Sanitary pontic • Modified sanitary pontic • Bullet pontic
- 19. PONTIC SELECTION The design of pontic for specific FPD is determined by: • Retainers • Esthetics • Occluso-gingival height and mesio-distal width of edentulous area. • Ridge resorption and contour.
- 20. TYPES OF PONTICS Saddle Pontic: • Forms a large concave contact with the ridge obliterating facial lingual and proximal embrasures. • Also called as ridge lap because it overlaps the facial and lingual aspects of the ridge. • This design has been recognized as unclean and uncleanable. • It also causes tissue inflammation and hence, it’s not used.
- 21. Modified Ridge Lap Pontic: • It possesses convex surface for ease of cleaning. • There is slight facio-lingual concavity on facial side of the ridge, which can be cleaned and tolerated by tissue. • The contour of the tissue contacting area should be convex. • It’s the most commonly used pontic design in combination with a porcelain veneer, in esthetic zone for both maxillary and mandibular FPD.
- 22. Hygienic/Sanitary/Wash Through Pontic: • Its termed so as these pontics have no contact with edentulous ridge. • It’s used in areas that are not easily visible – mandibular 1st molar. • The occluso-gingival thickness of pontic should be minimum 3.0 mm along with adequate space underneath to facilitate cleaning. • Types – Conventional, bar type and modified sanitary pontic. • The round design of the undersurface has been described as “fish belly”. • An esthetic version of this pontic can be created by veneering those parts that are likely to be visible with porcelain. This design is called arc-fixed partial denture/modified sanitary/Perel pontic.
- 23. Conical Pontic: • It’s rounded and cleanable, but the tip is small in relation to the overall size of the pontic. • Well suited for thin mandibular ridge. • Its use is limited to replacement of teeth over thin ridges in areas that are not highly visible.
- 24. Ovate Pontic: • It’s a round-end design currently in use where esthetics is a primary concern. • The tissue contacting segment is bluntly rounded, set into a concavity in ridge(created by extending one quarter of provisional FPD into socket immediately after extraction or can be created surgically). • It’s well suited for a broad flat ridge, giving appearance that it is growing from the ridge.
- 25. OTHER DESIGNS 1) TRUPONTIC: • It has a horizontal tubular slot running in the centre of the lingual surface of the facing. • Indicated in limited interarch distance. 2) FLAT BACK FACING/ INTERCHANGEABLE FACING • It consists of a vertical slot in its flat lingual surface. • Facing is retained by a backing with a lug(elevation),which is designed to engage the retention slot.
- 26. 3) PIN FACING: The lingual surface of the facing is flat and consists of two pins for retention. 4) MODIFIED PIN FACING: The flat lingual surface of the pin facing is modified by adding additional porcelain onto the gingival portion of its lingual surface.
- 27. 5) HARMONY FACING: • Facing consists of a flat lingual surface with two retentive pins. • Not indicated for cases with decreased occluso-gingival height as placement of the pins are difficult. 6) PORCELAIN FUSED TO METAL FACING: • Facing consists of a metal core over which porcelain is fused to closely resemble the contours of a natural tooth. • More esthetic. • Indicated for anterior teeth.
- 28. SPECIAL PONTICS 1) Quinn’s Pontic 2) Arthur Lowery Pontic 3) Preformed pontic pattern 4) Pontic clasp 5) Aligner orthodontic pontic 6) Notch pontic system 7) Schwartz pontic 8) Hidden attachment pontics 9) Articulated pontics
- 29. PONTIC MODIFICATION • In ridges with severe defects where two or more pontics must be used to fill the space, it is uncommon to eliminate gingival embrasure spaces between the pontics. • The so-called black triangles can be very unesthetic, they collect plaque, interfere with passage of floss and reduce rigidity of pontic span. • In such situations, pink porcelain can be added to gingival embrasure area of the pontic to simulate interdental papilla. • The gingival extension of porcelain must be supported by the metal framework.
- 31. • The full arch impression is poured, filling the prepared teeth and one teeth on either side of them. • The die is then trimmed. • The dies are left attached with a common base, which will retain the exact relationship of the two preparations. • The dies are coated with cement spacer and lubricant.
- 33. Wax removed in previous step is added to the underside of the pontic
- 34. More plaster is added to the facial surface of the pontic. If the FPD is to be cast in two pieces,3-0 suture silk can be used to saw through the connector.
- 36. POST-INSERTION HYGIENE • If cleaning is not done at frequent, regular intervals, the tissue around the pontic will become inflammed. • Hence, after an FPD is cemented, the patient should be taught appropriate technique and should be motivated to practice good hygiene around and under the pontic with dental floss, interproximal brushes or pipe cleaners. • The embrasure areas of the pontic should be wide open to allow easy access for cleaning and contact between pontic and tissue must allow passage of floss from one retainer to another. • The patient should be given time to learn the techniques. • Homecare is evaluated at each appointment.
- 37. CONCLUSION • The pontic design is said to determine the success and failure of the bridge. • Designs that allow easy plaque control are important to a pontic’s long term success. • Minimizing tissue contact by maximizing the convexity of the pontic’s gingival surface is essential. • Consideration is needed to create a design that combines easy maintenance with natural appearance and adequate mechanical strength.
- 38. REFERENCES • Fundamentals of fixed prosthodontics – By Schillingburg (4th edition).
- 39. THANK YOU