Dental Tribune UK Edition, October 25-3, 2010, No.26 Vol.4

Fig 2: Initial cavity preparation after removal of the defective composite restora- tion. Fig 3: SonicFlex air-driven scaler (KAVO) and SonicSys Prep Ceram Tips (KAVO) that were used to redefine the margins of the proximal boxes. Fig 5: Angulated view of final cavity preparation. Note the extended depth of the distal gingival margin from the oc- clusal surface. October 25-31, 201026 United Kingdom EditionClincal or to create adequate geometry to the cavity preparation for inlay / onlay preparation techniques (Dietschi & Spreafico, 1997). The shape of the cavity preparation will depend on the extent of the decay or the geometry of the res- toration to be replaced. The re- moval of decay often creates un- wanted undercuts which are not compatible with the principles of cavity preparation design for in- lays/onlays. In order to preserve sound enamel/dentine as much as possible, the internal tapered design should be obtained by the application of a base material (Di- etschi & Spreafico, 1997). Sherrer et al., 1994 demonstrated that the resistance to fracture for full ce- ramic crowns is significantly in- fluenced by the elasticity of the core material and luting cement. Because of the favorable proper- ties of the SDR material the au- thor is of the opinion that it might be the ideal material to block out undercuts in order to preserve additional enamel for adhesion and to improve cuspal strength during ceramic inlay cavity prep- arations. Figures 20 -29 depicts a clinical case report to illustrate the clinical application of the SDR flowable base material to allow ideal cavity preparation design for indirect posterior inlay /onlay restorations. Conclusions Providing the clinician with a flowable base material for pos- terior direct and indirect resto- rations that can be placed and cured in bulk must be one of the most exciting technological ad- vancements in dentistry towards technique simplification for what is generally regarded as a highly technique sensitive procedures. The fact that SDR exhibits ex- cellent adaptation to the prepa- ration walls due to its flowable nature, reducing the potential for void formation on the margins that could lead to post-operative sensitivity or aesthetic failure of the restoration. Another unique characteristic of the SDR mate- rial is the self-leveling feature which eliminates the need to ma- nipulate or sculpt the material before curing. This also creates an ideal surface for the addition of any regular viscosity compos- ite resin to complete direct res- torations, providing the desired strength, aesthetics and wear resistance for occlusal surfaces. The reduced polymerization stress of the SDR base material on normal and compromised cusps after conventional cav- ity preparation might provide the clinician with an improved and simplified operative technique to provide patients with more dura- ble posterior restorations. Reprinted with permission courtesy of International Dentist- ry South Africa © 2010. Van der Vyver P. Clinical application of a new flowable base material for di- rect and indirect restorations. Int Dent S Afr 2010;12(5):18-27“. DT page 26DTß Fig 1: Pre-operative view of an isolated up- per right maxillary sextant. Examination of the upper right first premolar revealed a defective composite restoration. Note the poor interproximal contact between the premolar and canine as well as the inad- equate contour on the distal aspect of the existing composite restoration. www.kavo.com/instruments Freephone no. 0800 281020