Bridge Pontic PDF

# Bridge Pontic ## Yasser M. Aly **(BDS 2006, MSc 2013 & PhD 2019)** Lecturer of Fixed Prosthodontics Faculty of Dentistry, Alexandria University # Definitions ## Fixed partial denture (Bridge): A prosthetic appliance, permanently attached to remaining teeth to replace one or more missing tee...

# Bridge Pontic ## Yasser M. Aly **(BDS 2006, MSc 2013 & PhD 2019)** Lecturer of Fixed Prosthodontics Faculty of Dentistry, Alexandria University # Definitions ## Fixed partial denture (Bridge): A prosthetic appliance, permanently attached to remaining teeth to replace one or more missing teeth. ## Fixed partial denture Abutments: It is the natural tooth, which supports the bridge (FPD). ## Retainer: It is the part of the bridge which retain the bridge to the abutments. ## Fixed partial denture Pontic: It is the part of the bridge which replaces the lost natural tooth, both esthetically and functionally. - They must be compatible with continued oral health and comfort. Proper preparation includes a careful analysis of the critical dimensions of the edentulous areas: mesiodistal width, occlusocervical distance, buccolingual diameter, and location of the residual ridge. To design a pontic that will meet hygienic requirements and prevent irritation of the residual ridge, particular attention must be given to the form and shape of the gingival surface. # Selection of Pontic (according to Rosenstiel et al) | | With Mucosal Contact | Without Mucosal Contact | | :------------------------ | :------------------------------------------ | :-------------------------------------- | | **Contact with ridge Mucosa** | Full facial contact | No contact with the ridge mucosa | | **Approx. 3mm above cervical contact** | Contact with ridge Mucosa | Approx. 3mm above cervical contact | | **More Aesthetic** | More Aesthetic | More hygienic | | **Usually for anterior teeth** | Usually for anterior teeth | Usually suitable for posterior teeth | | **Examples:** | Stein pontic, ridge lap pontic, Modified ridge lap pontic, Ovate pontic | Bullet Pontic, Hygienic / Sanitary pontic | # Pontic function - **To restore:** - Mastication - Speech - Esthetics (Affect the psychological make-up of the patient). - **To maintain:** - Inter-arch tooth relationships - Intra-arch tooth relationships - Gingival health (Affect the occlusal harmony # PRETREATMENT ASSESSMENT Certain procedures will enhance the success of a fixed partial denture (FPD). In the treatment-planning phase, diagnostic casts and waxing procedures may prove especially valuable for determining optimal pontic design. **Regarding:** - Pontic space - Residual ridge contour - Surgical modifications # I. Pontic space One function of an 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. At this point, creating an acceptable appearance without orthodontic repositioning of the abutment teeth is often impossible, particularly if esthetics is important. # II. Residual ridge contour The edentulous ridge's contour and topography should be carefully evaluated during the treatment planning phase. An ideally shaped ridge should posses: - smooth, regular surface of attached gingiva, which facilitates maintenance of a plaque-free environment. - Its height and width should allow placement of a pontic that appears to emerge from the ridge and mimics the appearance of the neighboring teeth. Loss of residual ridge contour may lead to unesthetic open gingival embrasures ("black triangles"), food impaction and percolation of saliva during speech. Siebert classified residual ridge deformities into three categories (Fig. 20-5): - Class I defects: faciolingual loss of tissue width with normal ridge height - Class II defects: loss of ridge height with normal ridge width - Class III defects: a combination of loss in both dimensions # III. Surgical Modifications There is a high incidence (91%) of residual ridge deformity after anterior tooth loss; the majority of these are Class III defects. Because patients with Class II and III defects are frequently dissatisfied with the esthetics of their FDPs, preprosthetic surgery to augment such residual ridges should be carefully considered. ## Class I defects Soft tissue procedures have been advocated for improving the width of a Class I defect; however, because Class I defects are infrequent and are not esthetically challenging, surgical augmentation of ridge width is uncommon. So, if surgery is needed - Roll technique: - Pouch technique: Pouches may be prepared in the facial aspect of the residual ridge into which subepithelial or sub mucosal grafts harvested from the palate or tuberosity may be inserted. ## Class II & III defects Unfortunately, few soft tissue surgical techniques can increase the height of a residual ridge with predictability. - The interpositional graft is a variation of the pouch technique, in which a wedge-shaped connective tissue graft is inserted into a pouch preparation on the facial aspect of the residual ridge. - The onlay graft is designed to gain ridge height but also contributes to ridge width, which makes it useful for treating Class III ridge defects. It is a thick "free gingival graft" harvested from partial- or full-thickness palatal donor sites. # Gingival Architecture Preservation Preservation of the alveolar process can be achieved through immediate restorative and periodontal intervention at the time of tooth removal. By conditioning the extraction site and providing a matrix for healing, the pre-extraction gingival architecture, or “socket,” can be preserved. # Pontic Classification Pontic designs are classified into two general groups: those that contact the oral mucosa and those that do not. Pontic selection depends primarily on esthetics and oral hygiene. In the anterior region, where esthetic appearance is a concern, the pontic should be well adapted to the tissue to make it appear as if it emerges from the gingiva. Conversely, in the posterior regions (mandibular premolar and molar areas), contours can be modified in the interest of designs that are less esthetic but amenable to oral hygiene. ## Types of pontics **According to design:** * With Mucosal contact: * Ridge lap * Modified ridge lap * Ovate * Conical * Without Mucosal contact: * Sanitary (hygienic) * Modified sanitary (hygienic) **According to material:** * All metal * All ceramic * All acrylic * Metal-combination * Metal-ceramic * Metal-acrylic ## I. NO MUCOSAL CONTACT - **Sanitary or Hygienic Pontic:** * The primary design feature of the sanitary pontic allows easy cleaning, because its tissue surface remains clear of the residual ridge.. * This hygienic design permits easier plaque control by allowing gauze strips and other cleaning devices to be passed under the pontic. - **Disadv:** * Entrapment of food particles, which may lead to tongue habits that annoy the patient. * Can't be used in Esthetic areas. - **Modified Sanitary or Hygienic Pontic:** * Its gingival portion is shaped like an archway between the retainers. This geometry allows increased connector size while decreasing the stress concentrated in the pontic and connectors. * Less susceptible to tissue proliferation that can occur when a pontic is too close to the residual ridge. * It used when the occluso gingival height of the edentulous space is insufficient for sanitary pontic in the lower molar region. ## II. MUCOSAL CONTACT - **Saddle or Ridge Lap Pontic :** * The saddle pontic has a concave fitting surface that overlaps the residual ridge buccolingually, simulating the contours and emergence profile of the missing tooth. * Should be avoided because the concave gingival surface of the pontic is not accessible to cleaning with dental floss, which leads to plaque accumulation, and tissue inflammation. - **Modified Ridge Lap Pontic :** * Combines the best features of the hygienic and saddle pontic designs, combining esthetics with easy cleaning. * The modified ridge lap design is the most common pontic form used in areas of the mouth that are visible during function (maxillary and mandibular anterior teeth and maxillary premolars and first molars). - **Conical pontic:** * Often called egg‑shaped, bullet‑shaped, or heart‑shaped. * It should be made as convex as possible, with only one point of contact at the center of the residual ridge. * Recommended for the replacement of mandibular posterior teeth. * This type may be unsuitable for broad residual ridges, because the emergence profile associated with the small tissue contact point may create areas of food entrapment. - **Ovate pontic:** * The ovate pontic is the most esthetically appealing pontic design. * Its convex tissue surface resides in a soft tissue depression or hollow in the residual ridge. * Socket preservation techniques should be performed at the time of extraction to create the tissue recess from which the ovate pontic form will emerge. * Or Soft tissue augmentation technique done * **Disadv:** * Meticulous oral hygiene measure to be followed. * Need for surgical tissue management and the associated cost. ## SUMMARY | Pontic Design | Appearance | Recommended location | Advantages | Disadvantages | Indications | Contraindications | Materials | |---|---|---|---|---|---|---|---| | Sanitary/hygienic | | Posterior mandibule | Good access for oral hygiene | Poor esthetics | Nonesthetic zones | Where esthetics is important | All metal | | Saddle-ridge-lap | | Not recommended | Esthetic | Not amenable to oral hygiene | Not recommended | Not recommended | Not applicable | | Conical | | Molars without esthetic requirements | Good access for oral hygiene | Poor esthetics | Posterior areas where esthetics is of minimal concern | Poor oral hygiene | All metal | | Modified ridge-lap | | High esthetic requirement (Le., anterior teeth and premolars, some maxillary molars) | Good esthetics | Moderately easy to clean | Most areas with esthetic concern | Where minimal esthetic concern exists | Metal-ceramic | | Ovate | | Very high esthetic requirement Maxillary incisors, canines, and premolars | Superior esthetics Negligible food entrapment Ease of cleaning | Requires surgical preparation Not for residual ridge defects | Desire for optimal esthetics High smile line | Unwillingness for surgery Residual ridge defects | Metal-ceramic | # Ideal Pontic * **Biologic** * Can maintain healthy tissues * Cleansable * **Mechanical** * Strong enough to withstand functional forces * Rigid & resistant to deformation * Provides normal function * **Esthetic** * Looks like the tooth it replaces * Tissue contacts appear as normal tooth # Principles for pontic design * It is not sufficient just to duplicate the missing tooth or teeth. * The successful pontic must be carefully designed and contoured to combine the: * Biological. * Mechanical * Esthetic principles. # I. Biological considerations * The pontic should just touch the ridge without pressure. * The gingival surface should be convex, free from any concavity or depression with minimal tissue contact. * The proximal surfaces should be designed to provide adequate embrasures * The following should be considered for the maintenance and preservation of the residual ridge, abutment and opposing teeth, and supporting tissues. * Ridge Contact * Oral Hygiene considerations * Pontic material * Occlusal forces ## A. Ridge Contact: * Pressure-free contact between the pontic and the underlying tissues is indicated to prevent ulceration and inflammation of the soft tissues. * Any blanching should be marked and corrected. * The pontic should just touch the ridge without pressure. * The gingival surface should be convex, free from any concavity or depression with minimal tissue contact. * The proximal surfaces should be designed to provide adequate embrasures. ## B. Oral Hygiene Consideration: * The chief cause of ridge irritation is the toxins released from microbial plaque accumulated around teeth. * The gingival surface should be convex, free from any concavity or depression with minimal tissue contact. * The proximal surfaces should be designed to provide adequate embrasures. * Use of: proxy brushes, pipe cleaners, Oral-B Super Floss ## C. Pontic material: * Any material chosen to fabricate the pontic should provide: * Good esthetics * biocompatibility * Rigidity, and strength to withstand occlusal forces * Longevity. * Glazed porcelain considered the most biocompatible of the available pontic materials. * Well-polished gold * I.e. Oral hygiene instructions ## D. Occlusal forces * Reducing the buccolingual width of the pontic by as much as 30% has been suggested ? studies * Pontics with normal occlusal widths (at least in the occlusal third) are generally recommended. * Except; diminished alveolar ridge BL. # II. Mechanical considerations The prognosis of FPD pontics is compromised if mechanical principles are not followed. Mechanical problems may be caused by improper choice of materials, poor framework design, poor tooth preparation, or poor occlusion. ## Available pontic materials.... ### Metal-ceramic pontics - **Should posses:** * The framework must provide a uniform veneer of porcelain (approximately 1.2mm). Excessive thickness of porcelain contributes to inadequate support. * The metal surfaces to be veneered must be smooth and free of pits. Surface irregularities cause incomplete wetting by the porcelain slurry. * Sharp angles on the veneering area should be rounded. They produce increased stress concentrations that can cause mechanical failure. * The location and design of the external metal porcelain junction require particular attention. Contact 1.5 mm away from junction ### RESIN-VENEERED PONTICS * Resistance to abrasion is lower than enamel or porcelain. * No chemical bond existed between the resin and the metal framework. * New-generation indirect resins- High flexural strength, minimal polymerization shrinkage, and wear rates comparable with those of tooth enamel ### FIBER-REINFORCED COMPOSITE RESIN PONTICS * Composite resins can be used in fixed partial dentures without a metal substructure. * A substructure matrix of impregnated glass or polymer fiber provides structural strength. * Excellent marginal adaptation and esthetics. # III. Esthetic considerations No matter how well biologic and mechanical principles have been followed during fabrication, the patient will evaluate the result by how it looks, especially when anterior teeth have been replaced. **Care to the following:** * Gingival interface * Incisogingival height * Mesiodistal width * Gingival mask ## Gingival interface * An esthetically successful pontic will replicate the form, contours, incisal edge, gingival and incisal embrasures, and color of adjacent teeth. * Special attention should be paid to the contour of the labial surface as it approaches the pontic-tissue junction to achieve a "natural" appearance. * This cannot be accomplished by merely duplicating the facial contour of the missing tooth. * If the original tooth contour were followed, the pontic would look unnaturally long incisogingivally. * Special care must be taken when studying where shadows fall around natural teeth, particularly around the gingival margin. * If a pontic is poorly adapted to the residual ridge, there will be an unnatural shadow in the cervical area >> spoils the illusion of a natural tooth. * The modified ridge-lap pontic is recommended for most anterior situations; it compensates for lost buccolingual width in the residual ridge by overlapping what remains * However, When appearance is of utmost concern, the ovate pontic, used in conjunction with alveolar preservation or soft tissue ridge augmentation ## Incisogingival height * Ridge resorption will make a pontic look too long in the cervical region. * This fact can be used to produce a pontic of good appearance by recontouring the gingival half of the labial surface. * In areas where tooth loss is accompanied by excessive loss of alveolar bone, the pontic is shaped to simulate a normal crown and root with emphasis on the cementoenamel junction. * The root can be stained to simulate exposed dentin. * If augmentative measures are contraindicated or undesirable, small alveolar deficiencies and missing papillae can be reconstructed by restorative measures. * Gingival porcelain can be used ## Mesiodistal width * If the space available for a pontic is greater or smaller than the width of the contra lateral tooth. * Such a discrepancy should be corrected by orthodontic treatment. * Or an acceptable appearance may be obtained by incorporating visual perception principles into the pontic design. * The features of the contra lateral tooth should be duplicated as precisely as possible in the pontic, and the space discrepancy can be compensated by altering the shape of the proximal areas. # Historical prefabricated pontics * Trupontic * Interchangeable facings * Pin facing * Modified Pin Facing * Reverse pin facing # 5.Prefabricated pontics * Flat back * Trupontic * Longpinfacing * Pontips * Reverse pin facings # Reference Contemporary of Fixed Prosthodontics, 5th edition. # THANK YOU