Purpose: The purpose of this in vitro study was to evaluate marginal fit of cobalt- chromium (Co-Cr) copings fabricated by direct metal laser sintering system (DMLS) and conventional lost-wax technique (LW). Materials and method: Forty tooth preparations were carried out over extracted mandibular molars. They were divided into two groups A and B of 20 each. For group A Co-Cr copings were fabricated by direct metal laser sintering (DMLS) and for group B by lost wax technique (LW). Glass –ionomer cement (GIC) was used to tack the copings over their preparations. Marginal fit was then evaluated directly under the stereomicroscope. Results: The mean marginal gap of group A was 27.9 ± 2.4 μm and group B was 40.4 ±6 μm. Statistical analysis using t - test showed highly significant difference (P>.05) between the marginal mean of the DMLS (group A) compared to LW (group B). Conclusion: The DMLS copings demonstrated superior marginal fit compared to that of conventional Co-Cr casted copings.

Lip has an important role in esthetics and phonetics of an individual. Damage to marginal mandibular nerve leads to loss of motor function and muscle tone of the affected side of lip. Eventually, it leads to loss of both primary functions of lip. Various surgical approaches of treatment do exist, but the treatment time is long and results are often not satisfactory. Prosthetically, these patients can be managed with the help of lip plumber prosthesis. This case report presents simple and accurate method to restore the harmonious relation of the lip.

Posts are widely used for restoring endodontically treated teeth with insufficient coronal tooth structure. Custom made cast metal post and core systems have a long history of successful use due to their superior physical properties. Prefabricated post systems have recently become more popular because they can provide satisfactory results, while saving time and reducing costs. Materials and Method: Post spaces were prepared in 60 extracted caries free teeth, and divided into two main groups of 30 teeth each for cast metal and glass fibre posts. These groups were further divided into 3 subgroups of 10 specimens each I) Control group without any surface treatment, II) Specimens treated with 57% ethanol, III) Specimens air abraded with 50um air borne alumina particles. Teeth were mounted in acrylic blocks prepared from a specially fabricated metal device. Posts were luted in the prepared post spaces with glass ionomer luting cement. Retentive strength was tested by Universal testing machine at 2mm/min crosshead speed. Results: Sand blasting of cast metal posts showed more significant improvement in retention compared to both control group and ethyl alcohol treated groups. In case of glass fibre posts, sand blasting significantly improved its retention compared to control group but no significant difference was observed between control and ethyl alcohol treated groups. There was also no significant difference between ethyl alcohol treated and sand blasted group. Conclusion: It was concluded that, sand blasting is an effective method to improve retention of both cast metal and glass fibre posts.