Fracture Resistance Of Adhesive Slot Restorations T.H. Schünemann*; G.M. Lösche; J.-F. Roulet (Dept. Of Operative And Preventive Dentistry, Charité, Humboldt University Of Berlin, Germany) Adhesive restorations are regarded the therapy of choice for small proximal lesions with maximum preservation of enamel and dentin. Prefabricated inserts, prefabricated inlays in standardized cavities (Sonicsys-approx-system; KaVo) and lab made inlays have been recommended to compensate for shortcomings of composite only restorations. The purpose of this study was to evaluate the strength of these restorative techniques.   50 extracted human molars were randomly assigned to 5 groups (n=10). In 4 groups standardized slot cavities with cervical margins 1.5 ± 0.5 mm above the cemento-enamel junction were cut. Teeth were adhesivly filled (total etch technique; Syntac Single Component) with Tetric Ceram being placed in 3 increments (group 1), with Tetric Ceram and loose fitting prefabricated inserts (group 2), Tetric Flow and Tetric Ceram in combination with prefabricated Sonicsys inlays after standardized “finishing preparation” with Sonicsys-approx-system (group 3) or lab made ceramic inlays luted with Tetric Flow (group 4). 10 unprepared teeth served as control. After thermocycling (4000x, 5-55 °C) the teeth were subjected to compressive loading directed at 12.5° to the long axis of the teeth at a crosshead speed of 0.5 mm/min until fracture occured. Data were statistically analyzed using non parametric tests (p=0.05). The table shows the mean and standard deviation of the fracture resistance in N.   Material Group 1 Group 2 Group 3 Group 4 Group 5 Mean 522.3 671.1 457.1 496.1 562.6 Std. Dev. 186.0 286.1 157.3 192.6 151.6   No statistical significant difference was found between all groups evaluated. Composite only restorations showed tendencially a higher fracture resistance but also a higher standard deviation.