This is-vitro study was conducted to find the importance of cavity designs in the fracture resistance of class II composite restorations in four different cavity designs. 32 freshly extracted teeth were used in the study. Group I received a mesio-occlusal preparation with extension through the occlusal groove into the central fossa. Group II received a mesio-occlusal slot preparation with retention grooves extending from the gingival floor to the occlusal surface at the axiofacial & axiolingual line angles. Group III received a mesio-occlusal slot preparation as in group II but without retentive grooves; Group IV received a mesio-occlusal slot preparation, without removal of facial or lingual portions of the mesial enamel shell. After the restorations were thermocycled, their marginal ridges were flattened & loaded to failure. Mean (SD) failure loads were 392.37(79.96) N in group I, 353.81(49.23)N in group II, 257.36(73.42)N in group III and 284.73(73.56)N in group IV. Mean failure loads of group I and II were not significantly different from each other but very significantly greater than failure loads of group III and IV. Mean failure loads of group III and IV were not significantly different.

A clinical and scanning electron microscope study was carried out of investigate the effectiveness of SCOTCHBOND and DENTIN ADHESIT bonding agents for retention and adaptation of composite resin in C1. V. restorations. Clinical study comprised of 120 restorations and SEM study comprised of 64 restorations. The teeth were divided into four groups namely A,B,C and D. SCOTCHBOND was used with acid etch technique in Group A and it was used with non acid etch technique in Group B . While DENTIN ADHESIT was used in acid etch technique in Group C and it was used in non acid etch technique in Group D. SCOTCHBOND showed better results when compared with DENTIN ADHESIT in clinical study. In in-vitro study, SCOTCHBOND gave better adaptation to cavity margins at different at different levels of enamel, dentin and D.E. Junction compared to DENTIN ADHESIT. Overall result was in favour of acid etch technique in both the studies.

Conventionally endodontically- treated young permanent molars have been restored using a preformed stainless steel crown restoration. This article presents an alternative treatment modality using Composite Resin Onlays by Indirect Technique. A long-term clinical evaluation of treated cases is also presented.