Clinical Steps of Direct Composite Resin Restorations PDF

CLINICAL STEPS OF DIRECT COMPOSITE RESIN RESTORATIONS DDS.PHD. Z. MERİÇ ERAYDIN EUL FACULTY OF DENTISTRY, 2024  There is no single blueprint for posterior composite restorations. Efficiency, predictability, durability, esthetics – many factors come...

CLINICAL STEPS OF DIRECT COMPOSITE RESIN RESTORATIONS DDS.PHD. Z. MERİÇ ERAYDIN EUL FACULTY OF DENTISTRY, 2024  There is no single blueprint for posterior composite restorations. Efficiency, predictability, durability, esthetics – many factors come into play with each choice of material and technique. Before you start the treatment ensure that the room is properly prepared with all the necessary armamentarium (the medicines, equipment, and techniques available to a medical practitioner.). Be sure to confirm diagnosis and treatment plan with charts and Composite resin application process; The composite application procedure have several stages and the correct execution of these steps is crucial for the longevity of the restoration and clinical success. These procedure stages include;  initial cavity preparation,  tooth tissue etching, and  application of a compatible bonding system,  followed by polymerisation,  occlusal adjustment and  polishing of the previously placed RBC restoration.  Too Too light dark Cavity Preparation If the proximal wall is too high, the occlusal contact will fail due to the excessive height of the filling, requiring significant adjustments. To avoid extra work and make the height of the surface more predictable in occlusion, we can use a periodontal probe. On the cavity floor, in direct contact with the enamel-dentin adhesive, it is advisable to use flowable composites that are more elastic than dentin and microhybrid composites with higher internal flow that can compensate for shrinkage stress. Flowable composites are used in a thin layer to improve the fit between the adhesive and the composite and reduce the risk of postoperative sensitivity. It is important to consider the cavity C-factor, described by Feilzer, De Gee and Davidson (1987), which considers the relationship between cavity configuration and shrinkage stress based on the relationship between bonded and unbonded surfaces—in other words, the inversely proportional relationship between the number of cavity walls and preservation of adhesion (Davidson, De Gee, and Feilzer, 1984). C-factor stands for configuration factor and expresses the ratio of internal walls versus external surfaces. A second way to describe C-factor is internal surface area versus external surface area. C-factor is a fundamental flaw in traditional cavity preparations because the parallel walls for resistance and retention work against the dentist during polymerization shrinkage. As the curing light hits the composite, it will shrink toward the center. The shrinkage can be measured as either volume or linearly. On a linear basis, most direct composites shrink 2% to 5%. The shape of the cavity preparation, the number of opposing walls, how they oppose one another, and the angle at which they oppose one another are extremely critical to the behavior of composite shrinkage. A, Chemically polymerized composite resin shrinks toward the center of the mass. This happens if the composite is not bonded. Composites shrink toward the adhesively bound surfaces. This process leaves a small contraction gap at the gingival margin. B, Photopolymerized composite resin shrinks toward the light source because the composite resin closest to the light hardens first. This pulls the softer composite resin from the gingival areas, creating a gap. C, Incremental curing reduces but does not completely eliminate the gingival contraction gap. D, A plastic wedge, which acts as a fiberoptic extension, can pull the composite resin gingivally to minimize gap formation. E, Although not ideal, this incremental technique should reduce the gingival contraction gap and the stress better than a two-increment technique involving only occlusal curing. The first layer is placed and photopolymerized through the plastic wedge. A second layer is placed and polymerized occlusally. F, The first increment can be pulled lingually and gingivally. The second increment is pulled buccally and gingivally. The definitive increment is hardened. Additional occlusal increments may be necessary in large teeth. This design also minimizes pulling together of the cusps. Source: (Modified from Lutz F et al: Improved proximal margin adaptation of Class II composite resin restorations, Quintessence Int 17:659, 1986.)  COMPOSITE LAYERING TECHNIQUES Based on the complexities with polymerization shrinkage, different approaches to composite placement have been proposed to reduce composite resin failure. When placing posterior composites, the use of small increments is recommended by many authors for insertion and polymerization so that the after effect of shrinkage stress can be reduced. To reduce shrinkage stress, composite resins should be inserted in the cavity using the incremental technique (2 mm max). However, the incremental insertion method has some disadvantages: air bubbles, bond failures and contamination and longer clinical time to perform the restoration. To overcome the disadvantages of the conventional composites, bulk-fill composite resins have been introduced which are inserted in the dental cavity in increments of 4-5 mm thick. Rosatto et al., in their study, suggested that Bulk-fill resins might be safely indicated for restorations in posterior teeth. Bulk-fill resin restorations in posterior teeth reduced deflection of the cuspid, polymerization shrinkage and shrinkage stresses, increasing the fracture strength. Many studies have reported satisfactory performance of Bulk-fill restorations in posterior teeth, presenting results similar to those of conventional composite resins. Thank you https://pocketdentistry.com/composite-resin- fundamentals-and-direct-technique-restorations/