CS2-17. Provisional Fixed Restorations - Assist. Prof. Dr. Delal Bozyel.pdf

Provisional Fixed Restoration Assist.Prof.Delâl Bozyel Learning Outcomes Determines the correct temporary fixed restoration material according to the case, selects the appropriate application technique. Temporary fixed restorations are fixed or removable prostheses made to improve aesthetics, st...

Provisional Fixed Restoration Assist.Prof.Delâl Bozyel Learning Outcomes Determines the correct temporary fixed restoration material according to the case, selects the appropriate application technique. Temporary fixed restorations are fixed or removable prostheses made to improve aesthetics, stabilization and function to be used until the delivery of permanent fixed prostheses to the patient. PROPERTIES OF TEMPORARY RESTORATIONS Protecting pulp compatible finish line Non-toxic provide chewing function and phonation low cost and easy to prepare INTENDED USE OF TEMPORARY RESTORATIONS • They give the dentist the ability to devote the required amount of time to each clinical procedure. • They allow visualisation of the anticipated desired aesthetic outcome. • Temporary restorations with well-fitting margins create the optimal tissue health and support needed for high-quality impressions. Without this, impressions tend to be unpredictable and compromised in quality which then jeopardises the final fit of the restorations. • Aesthetic temporaries elevate the patient’s and dentist’s expectations and encourage the technician to achieve an aesthetic result superior to that of the temporaries. TEMPORARY RESTORATION MATERIALS 1. Prefabricated Temporary Crowns They are used in single crowns and reflect anatomical features. Therefore, they require less correction and adaptation. Non-anatomical crowns, on the other hand, need significant contouring and adaptation to adapt to the tooth. TEMPORARY RESTORATION MATERIALS 1. Prefabricated Temporary Crowns Metal Crowns • Non-aesthetic • mechanical durability is good. Cellulose Acetate Crowns Polycarbonate Crowns • Thin and transparent • One colour • There are forms suitable for prepared teeth. • Aesthetic and natural • Polycarbonate material contours and crimps similar to metal crowns to yield easy adaptation to margins. TEMPORARY RESTORATION MATERIALS 1. Prefabricated Temporary Crowns Most Aesthetic TEMPORARY RESTORATION MATERIALS 2. Custom Temporary Crowns • These crowns are traditionally made of autopolymerizing acrylic or resin-based materials. For this purpose, materials such as ethylmethacrylate (PEMA), methylmethacrylate (PMMA), polyvinyl methacrylate, bis-acryl composite resin, urethandimethacrylate are used. TEMPORARY RESTORATION MATERIALS 2. Custom Temporary Crowns Ethylmethacrylate • • Low wear resistance Aesthetic is not enough Autopolymerizing Acrylic Resin • Pulpal and gingival irritation • Exothermic • Low mechanical resistance Resin Based • High vulnerability • Expensive • Not suitable for long bridges • Good color stability TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 1. Direct Technic • Before the tooth preparation, an impression is taken from the restoration area with a silicone-based impression material. • After the preparation, isolation is applied to the related tooth. • Temporary restoration material is placed in the preparation area in the silicone impression and placed in the mouth with the impression material before the polymerization is completed. • Without waiting for the end of the polymerization, the impression is removed from the mouth in order to prevent the heat that will occur during polymerization from damaging the pulp and soft tissues and to facilitate the removal of the hardened temporary crown from the prepared teeth. TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 1. Direct Technic No additional appointment is required. The patient does not feel pain. Repeatable. Should be careful. Causes sensitization in the pulp. TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 1. Direct Technic TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 2. Indirect Technic After the preparation, impression are taken from both jaws with alginate. Temporary restorations are made on the obtained model. Another method is to first create a wax sample of the desired form and size on the plaster model. Then, the impression is taken again with a hydrocolloid impression material on the model, the wax is removed, the temporary restorative material is placed and the impression is placed on the model. Following the polymerization of the material, necessary leveling and polishing processes are carried out. TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES Chemical effects are minimal. Shrinkage is controlled. Indirect Technic Marginal fits are good. Easy to manufacture. TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 2. Indirect Technic Ideal marginal fit Suitable for bridges Provides preparation control. Accepts material addition If the insulation is not provided well, breaks will occur in the model. Increases the cost. Coloration is seen. TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 2. Indirect Technic TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 3. Direct/Indirect Technic ➢ In this method, the outer surface form of the temporary restoration is obtained indirectly, and the inner surface form is obtained directly. ➢ First, an impression is taken with a hydrocolloid impression material before tooth preparation. A plaster model is obtained from the measurement. ➢ Before tooth preparation, a thin-walled temporary restoration in ideal contours is fabricated in the laboratory. ➢ Temporary restorations, which are ready with the dentist in the tooth preparation session, are completed by feeding with resin in the same session after the preparation phase is completed. TEMPORARY RESTORATION CONSTRUCTION TECHNIQUES 3. Direct/Indirect Technic ➢ The time in the patient chair is shortened, requiring less adjustment. ➢ The most important advantage is that the resulting polymerization heat is lower because the volume of the resin to be polymerized is smaller. ➢ In addition, the amount of polymerized resin that comes into contact with soft tissues is also reduced. ➢ If the restoration prepared at the laboratory stage is produced with hot acrylic, the resistance and color stability of the restoration can be increased. CEMENTATION OF TEMPORARY CROWNS The frequent dislocation of the temporary restoration is due to nonretentive tooth cutting and excessive cement cavity. The use of cements containing zinc oxide eugenol (ZOE) allows the temporary crown to be easily removed and reused between treatment sessions. It also has a sedative effect on the pulp and provides sealing. CEMENTATION OF TEMPORARY CROWNS Stronger cements can be used in cases where the tooth preparation is retentively inadequate, the gap between the tooth and the restoration is large, long-term waiting is required or there are parafunctional habits. Reinforced ZOE, or ogenol-free zinc oxide, is more durable than ogenol-containing cements. If the permanent restoration is to be bonded with a resin cement, an ogenol-free cement should be used for temporary restorations as ogenol will affect the bond strength. CEMENTATION OF TEMPORARY CROWNS Failure to remove cement residues after cementation may cause bone loss with gingival inflammation and various periodontal problems. Therefore, the sulcus should be carefully controlled and irrigated using an air-water syringe. CONCLUSION While performing fixed prosthetic restorations, temporary restoration application is very important in order to protect the prepared teeth until the permanent restorations are prepared, to provide patient comfort and to gain aesthetics to the patient within this period. Preparing a successful temporary restoration will also be a good preparation for permanent restoration. It is important to evaluate the temporary restoration preparation technique and material on a case-by-case basis and to perform meticulous cementation. REFERANCES • Gegauff AG, Holloway JA. Interim fixed restorations. In: Rosenstiel SF, Land MF, Fu- jimoto J .Contemporary Fixed Prosthodontics 3rd ed.Missouri : Mosby Elsevier; 2006. p. 466- 501. • Burduroğlu, H. D. (2015). Çeşitli Geçici Kron Materyallerinin Mekanik ve Fiziksel Özelliklerinin in-Vitro Karşılaştırılması. • Luthardt, R. G., Stößel, M., Hinz, M., & Vollandt, R. (2000). Clinical performance and periodontal outcome of temporary crowns and fixed partial dentures: A randomized clinical trial. The Journal of prosthetic dentistry, 83(1), 32-39. Thank you