In order to derive the equation of the contact line of the involute curvilinear-tooth cylindrical gear pump for the agricultural tractor, the tooth surface of the involute curvilinear-tooth cylindrical gear is firstly generated as that of the spur or helical gear. Then the equation of the tooth surface is derived from changing the settings and orientations of the coordinate systems after the eq...

OBJECTIVE To determine the tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students. METHODS A descriptive cross-sectional study of students of Federal School of Dental Therapy and Technology Enugu, Nigeria. Self-administered questionnaire was used to obtain information on demography, frequency, duration and technique of tooth brushing and tongue clea...

Teeth are a classic model system of organogenesis, as repeated and reciprocal epithelial and mesenchymal interactions pattern placode formation and outgrowth. Less is known about the developmental and genetic bases of tooth formation and replacement in polyphyodonts, which are vertebrates with continual tooth replacement. Here, we leverage natural variation in the threespine stickleback fish Ga...

BACKGROUND Tooth wear has a multifactorial etiology, thus it should be assessed within a multiple-variable framework. The objective of this investigation was to assess the association of dietary habits and parental-reported sleep tooth grinding (STG) with tooth wear in children with mixed dentition. METHODS One hundred twenty-one (N = 121) subjects (mean age 9.6 years) participated in a cross...

PURPOSE The aim of this study was to examine the relationship between tooth loss and sub-clinical atherosclerosis in Korean adults. MATERIALS AND METHODS The subjects were part of a cohort study conducted in Ansan city by the Korea University medical school as part of the Korean Genome project. 749 subjects over than 40 years old were evaluated. After taking panoramic radiography, the amount ...

The design of a hybrid stepper motor for achieving a specific performance necessitates the choice of appropriate tooth geometry. In this paper, a detailed account of the results of twodimensional and three-dimensional finite-element (FE) analyses, conducted with different tooth width/tooth pitch ratios (t/X) and also with various tooth/slot shapes such as rectangular, trapezoidal, triangular, a...

This case report demonstrates intentional extraction of an endodontically compromised tooth followed by its intentional reimplantation to preserve the tooth and restore its functions. Re-implantation presents an alternative treatment option to preserve integrity of dentition in cases of poor prognosis where the tooth is damaged with multiple perforations or due to limited instrument access or p...

This study highlights the dynamic nature of the mesenchymal cells during tooth development from the bud to the bell stage. Condensing mesenchymal cells, labelled on either side of the developing tooth bud, move toward the presumptive roots forming an arc of cells under the dental papilla. These labelled cells take part in formation of the dental follicle, which contributes to both the tooth and...

Tooth eruption is a localized process in the jaws which exhibits precise timing and bilateral symmetry. It involves resorption and formation of bone on opposite sides of the erupting tooth and these activities depend on the dental follicle, a thin connective tissue investment of the developing and erupting tooth. Biochemical studies have shown that during eruption cells, proteins and enzymes ch...