ABSTRACT
Techniques for bonding denture teeth to acrylic resin denture base remains empirical, with little consensus from the literature, among clinicians or among dental laboratories. Despite of this great variation, the data available regarding effectiveness of various methods used are sparse. The study was carried out to compare the effect of different surface treatments of ridge lap area of acrylic resin denture teeth on bond strength of acrylic resin denture teeth with acrylic resin denture base. 180 Maxillary central incisors were divided into 6 groups of 30 each according to surface preparations. First group served as the control with no surface preparation; other groups included horizontal grooves, vertical grooves, diatorics, sand blasting and roughened surfaces. Compressive shear force was applied to incisal edge of each tooth until fracture occurred, the force recorded and teeth visually inspected to determine adhesive or cohesive failure. Significant increase in failure load ranged for diatoric 274 +/- 78N. Significant decrease in failure mode was observed after sand blasting 157 +/- 79N. Remaining groups showed non-significant increase in force required for bond failure
ABSTRACT
After loss of natural teeth, provision of prosthodontic services almost becomes necessity in the present day living. To provide effective mastication teeth have peculiar forms. To make it more efficient both functionally and biologically, they are arranged in particular geometric manner referred to as dental arch. The objective of this study was to compare the distance between mesial edge of the maxillary central incisors and posterior border of the incisive papilla in dentate individuals with different arch forms. After sample selection, impressions were made for upper and lower arches and the resultant casts were standardised. Arch forms were assessed by their morphological description. Measurements on cast were recorded for incisive papilla [IP] and maxillary central incisor [CI] distance after securing it on cast surveyor. Ovoid arch form was the most frequently observed arch form both in males [57%] and females [68%] while their combination [Ovoid Square and Ovoid tapered] were the least commonly observed arch forms [4% and 5% each]. Gender seems to be important in about 1/4[th] of the dentate individuals, regarding both the type of the arches and CI-IP distance. Ovoid type of arches was the commonest arch form seen in either sex. There is no significant difference between males and females in 3/4[th] of dentate individuals, regarding the type of dental arch as well as CI-IP distance
ABSTRACT
The objective of this study was to correlate shades of teeth to skin color according to age and gender. The study sample comprised 200 patients ranging in age from 16 to 55 years, divided into four age groups of 50 each. Shade of middle third of labial surface of maxillary central incisor was recorded visually with the help of Vitapan 3D-Master shade guide under standardized lighting. Color of back of the hands was recorded with the help of Ideal Balance Quick Stick makeup shades, and divided into three skin tone groups. The paired samples T-test was applied at 95% confidence interval. Our results revealed a significant association [P<0.001] when either age or gender was correlated with shades of teeth and color of the skin. It was concluded that both tooth shade and skin color were strongly related with each other and with the age and gender of the patients. This information can be used effectively for fabrication of more life-like dentures