Materials and methods: Helioseal and Delton Opaque fissure sealants were applied to pairs of contralateral mandibular second premolar teeth. Optically clear epoxy resin replicas were produced which were sequentially located and mounted within a defined plane. The replicas were transilluminated from below with diffused light, examined with a microscope and digital images captured. This allowed t...

Starting from 2-imino-N-phenyl-2H-chromene-3-carbox-amide, (1) a series of functionalized chromenes were achieved; such as, 2-ethoxy-2,3-dihydro-3-phenylchromeno[2,3-d]pyrimidin-4-one (2), and 2-hydrazinyl-2,3-dihydro-3-phenylchromeno-[2,3-d]pyrimidin-4-one (3). Furthermore, reactions of (3) with some of laboratory available compounds gave pyrazoles (4 9, 12, 13a, 13b), tetrazoles (11), 2-(2-be...

The purpose of this study was to compare the success rates of Class II subdivision malocclusion patients treated with either symmetric or asymmetric extractions. The sample consisted of 51 patients with Class II subdivision malocclusion. The patients were divided into 2 groups. Group 1 included 28 patients who were treated with 4 premolar extractions. The 23 patients in group 2 were treated wit...

OBJECTIVES Anterior maxilla, known as the esthetic zone, plays an important role in facial and smile esthetics. This study assessed the frequency of implant treatments in the esthetic zone of patients presenting to Dental Implant Department of Tehran University during 2002-2012. MATERIALS AND METHODS This descriptive study was conducted on dental records of patients receiving implant treatmen...

Missing of mandibular second premolar is one of the most common types of tooth agenesis. In such cases, maintenance of the primary second molar, if possible at all, can prevent many treatment procedures in future. The present case report represents the endodontic management of a necrotic left mandibular primary second molar that had developed an abscess. Considering the missing of the permanent...

Background: The purposes of this study were to determine the prevalence and patterns mandibular second premolar agenesis in individuals by meta-analysis methodology.Methods: Two investigators conducted a literature search independently inclusion criteria reveal articles on agenesis. PubMed, Google Scholar, Ovid Medline, Web Science Core Collection databases scanned total 3,988 studies initially...

The aim of the present study was to examine the morphology of root canals in premolar teeth with completely formed root apices. The material consisted of 139 extracted premolar teeth, including 83 first premolars (59.7%) and 56 second premolars (40.3%). Maxillary teeth made up 64% of the material and mandibular teeth 36%. In order to measure the actual root canal length an endodontic instrument...

Long-term success of endodontic treatment is strictly dependent on proper shaping and cleaning of the root canal system followed by obturation of entire prepared space. Anatomical variations should be considered during radiographic and clinical evaluation as parts of endodontic treatment. A mandibular premolar with three canals is quite rare and such a tooth requires special canal preparation a...

OBJECTIVE In this study, we measured the cortical bone thickness in the mandibular buccal and lingual areas using computed tomography in order to evaluate the suitability of these areas for application of temporary anchorage devices (TADs) and to suggest a clinical guide for TADs. METHODS The buccal and lingual cortical bone thickness was measured in 15 men and 15 women. Bone thickness was me...