introduction: permanent first molar is the most important unit in the chewing system. ear-ly loss of first molars can significantly reduce chewing efficiency, increase overbite, lead to premature eruption of the permanent second and third molars, and displacement of adjacent teeth. the purpose of this study was to determine the associated factors of permanent first molar caries in 7-9 years old...

introduction: knowledge of the anatomic location and dimension of the molar pulp chamber may preserve healthy pulp during operative procedure and reduce risk of perforation of chamber during access preparation. a review of literatures regarding the morphology of pulp chamber however revealed very little information; so the aim of this in vivo study was to measure the dimensions of first molar p...

abstract a32 year-old multigravid patient with 10 weeks of pregnancy was referred to the emergency ward with massive vaginal bleeding and preshock state. suction curettage, laparotomy, uterine artery ligation, macdonald cerclage, and hysterectomy was done, in that order. after hysterectomy and massive transfusion she recovered. when a diagnosis of cesarean scar pregnancy is made in the emergenc...

background and aims. due to anatomic variation in tooth anatomy between populations, this study compared the buccolingual (bl) and mesiodistal (md) dimensions of primary molars with those of stainless steel crowns (sscs) in an iranian population. materials and methods. impressions were taken from both dental arches of children, and casts were poured. teeth with caries, restoration, hypoplasia o...

conclusions however, root and canal anatomies of third molar teeth are unknown, but studies focusing on third molar teeth have shown their possibility of treatment. results according to the study on 173 mandibular third molars, 92.4%, 4.6%, and 2.89% had two, one, and three roots, respectively. majority of them had two or three canals and most of mesial root canals were type 2; but in 179 maxil...

introduction: having knowledge about the anatomy of root canal system is essential for success of endodontic treatment. the present study used cone-beam computed tomography (cbct), to evaluate the prevalence of third root in mandibular first molars in a selected iranian population. methods and materials: a total of 386 cbct images from subjects referred to oral and maxillofacial radiology depar...

This paper presents an experimental investigation of acoustic barrier composed out acousticmetamaterial unit cell. The design the cell consists a square prism, acting as resonator,within hexagonal recess manufactured single material. Two materials were used tomanufacture cell: PolyMide Polycarbonate and Polylite Polylactic Acid. acousticperformance was quantified for both using absorptioncoeffi...

A fully bonded m~dtiloop wire appliance for the correction of ectopically erupting permanent molars is described. The appliance allows control in the anteroposterior, vertical, and transverse planes. Ectopically erupting first permanent molars are seen in about 3% of the population.~,2 Sixty-six per cent of ectopically erupting maxillary first permanent molars self-correct by jumping over the i...

A simple method of treating an ectopically erupting first permanent molar is presented which utilizes both a molar band with helical finger springs cemented to a second primary molar, and a curved tag of composite resin which is acid-etched to the occlusal surface of the affected first permanent molar. When activated and placed into proper position, the springs act at right angles to the long a...