Background:The thermal expansion of the investment can be restricted by the metal casting ring because the thermal expansion of the ring is less than that of the investment. The ringless casting procedure is in use in clinical dentistry, though there is little scientific data to support its use in fixed partial dentures. In this study, marginal discrepancy of castings produced with the ringless casting technique and the conventional technique using the metal rings were compared. Materials and methods:A total of 30 wax patterns were fabricated directly on a metal die. Optical stereomicroscope was used to measure the marginal discrepancy between the metal die and wax patterns. A total of 15 castings were invested using Bellavest T phosphate-bonded investment with the ringless technique and 15 were invested with the same investment with a metal ring; 30 castings were produced using a nickel-chromium ceramo-metal alloy. The internal surface of the castings was not modified and seated with finger pressure. The vertical marginal discrepancy was measured using an optical stereomicroscope at a magnification of 100×. The data obtained were statistically analyzed using students t-test (paired t-test and unpaired t-test). Results

Background: The wrinkles and grooves visible on the lips form the characteristic pattern of an individual and imprints produced is termed as “lip print.” The study of these prints is known as “cheiloscopy.” Variations in patterns among males and females could help in sex determination. Lip prints, therefore, can constitute material evidence left at a crime spot, equivalent to fingerprints. These patterns are heritable and are believed to be unique and permanent. The lip prints of parents and children and those of siblings have been shown to have some similarities. The influence of inherited lip print patterns among family members is still a new concept and studies are scanty in literature. Objectives: The objectives are to determine the most common patterns and gender-wise distribution among the study population and to analyze the inherited lip print patterns from parents to their offspring. Materials and Methods: Lip prints of 30 families were obtained using lipstick and cellophane tape. Based on criteria given by Suzuki and Tsuchihashi, patterns were recorded and analyzed from four quadrants of the lips using a magnifying lens. Results: The positive resemblance of lip print patterns from parents to their offsprings showed statistically significant resemblance in one quadrant and rest of the three quadrants showed no significant association between parents and offspring. Conclusion: Positive resemblance among the family members can be attributed to the genetics and inheritance. Lip print can be considered as an auxiliary method of identification.