OBJECTIVES The aim of this study was to determine the apical surface characteristics and presence of dental cracks in single-rooted premolars, resected 3.0 mm from the root apex, using the Er: YAG laser, tungsten carbide bur, and diamond-coated tip, by scanning electron microscopy (SEM). EXPERIMENTAL DESIGN Thirty single-rooted premolar teeth were collected. The instrumented and obturated tee...

Orangutans are believed to have close biological affinities to humans. Teeth being the hardest tissue provide useful information on primate evolution. Furthermore, knowledge of the pulp chamber and root canal morphology is important for dental treatment. A female Bornean orangutan and a Sumatran male orangutan skull were available for this study. Both of their dentitions, comprising 50 teeth, w...

Earlier studies have reported extensive volumetric loss of fissure sealant shortly after placement. To determine the volume of fissure sealant lost at six months, we used a servohydraulic profilometric apparatus in combination with computer graphics. Twenty-two premolar teeth were selected, and baseline silicone impressions were made of each tooth. The teeth were sealed and the occlusion adjust...

CE Incisor malocclusion is common in rabbits. If this condition occurs as an isolated entity at an early age, it probably has a genetic origin. Incisor malocclusion in older animals is usually secondary to, or occurs concomitantly with, premolar–molar malocclusion. Therefore, patients with incisor malocclusion should always receive a comprehensive oral examination. Incisor–premolar–molar malocc...

The aim of this study was to compare smile attractiveness between one, three, and four premolar extraction protocols in patients with Class II division 1 subdivision malocclusions and to analyse the aesthetic influence of buccal and posterior corridor widths on smile attractiveness. The sample consisted of posed smile photographs obtained from 66 subjects, divided into three groups according to...

Three specific orthodontic tooth movement genes, that is, FCRL1, HSPG2, and LAMB2 were detected at upper first premolar (with appliance) dental pulp tissue by using GeneFishing technique as compared to lower first premolar (without appliance). These three differentially expressed genes have the potential as molecular markers during orthodontic tooth movement by looking at molecular changes of p...

We present a graph-theoretic model of discourse based on the Questions Under Discussion (QUD) framework. Questions and assertions are treated as edges connecting discourse states in a rooted graph, modeling the introduction and resolution of various QUDs as paths through this graph. The amount of common ground presupposed by interlocutors at any given point in a discourse corresponds to graphic...