Here, we report the effects of ring fusion, which causes expansion of the π-conjugation circuits of the porphyrin derivatives to the fused meso-aryl groups, on the aromaticity and the magnetic properties of porphyrin derivatives. These studies revealed the facts that the ring fusion with five-membered rings causes not only the remarkable red shifts of the absorption bands and narrowed HOMO-LUMO...

Dental anomalies of number and forms may occur in the primary and permanent dentition. Various terms have been used to describe dental twinning anomalies: Germination, fusion, concrescence, double teeth, conjoined teeth, twinned teeth, geminifusion, and vicinifusion. Fused tooth is a developmental anomaly that is seen more frequently in the primary than the permanent dentition. Double tooth inv...

AIM Understanding the effects of primary double tooth (PDT) on permanent successors is important to ensure healthy permanent occlusion and aesthetics. The aim of this study is to determine the prevalence and type of PDT, their effect on permanent successors, and the accompanying dental anomalies/pathologies in a Turkish population. MATERIALS AND METHODS Study design: The records of 63 PDTs in...

BACKGROUND To evaluate the efficacy of pulse oximeter as a pulp vitality tester. MATERIALS AND METHODS The sample group consisted of 60 patients of age 15 to 30 years with normal maxillary anterior teeth. Thirty nonvital teeth with complete endodontic fillings were tested as control group. Systemic oxygen saturation values from the patient's fingers served as the control sample for comparison...

A novel class of dibenzo-fused 1,9-diaza-9a-boraphenalenes featuring zigzag edges with a nitrogen-boron-nitrogen bonding pattern named NBN-dibenzophenalenes (NBN-DBPs) has been synthesized. Alternating nitrogen and boron atoms impart high chemical stability to these zigzag-edged polycyclic aromatic hydrocarbons (PAHs), and this motif even allows for postsynthetic modifications, as demonstrated ...

Z. Naturforsch. 54 b, 573-576 (1999); eingegangen am 28. Dezember 1998 Fused Salts, Monosilane, Methylsilanes, Hydrosilylation, Chloroaluminate Silanes of technical interest as starting compounds for semiconducting materials or hydrosi­ lylation reactions, (CH3)xSiH4_x (x = 0, 1,2, 3), are obtained by direct hydrogenation of the corresponding chlorosilanes in the presence of various interstitia...

Since abnormal tooth morphology can predispose to caries and periodontal disease, careful management of fused teeth is essential. In this paper we report a rare case of a fused molar and supernumerary tooth and describe its management. Caries was removed from the tooth complex under local anesthesia. The pulp chamber of the supernumerary tooth was exposed without involvement of second molar pul...

Aim: To investigate the prevalence of eight morphological and numerical anomalies in the southern Chinese permanent dentition and to compare these with studies from different populations. Materials and Methods: The material used in the study consisted of study models and panoramic radiographs collected from 725 randomly selected 12-year-old children (358 males and 367 females). The anomalies we...

Case description: In the first case, the patient was referred by an orthodontist for endodontic treatment of tooth 12, which was fused to 13. Surgical separation and later replacement of the involved elements in the dental arch was indicated. In the second case, the patient sought dental attendance due to spontaneous pain. In the radiographic exam, gemination in tooth 11 and fusion of 21 with a...

OBJECTIVE To evaluate the effect of water storage on surface roughness (Ra) of human enamel after treatment with resin infiltrant and fissure sealant, by utilizing atomic force microscopy (AFM) and microtomography. METHODS This study was conducted after registration and ethical approval clarification at the College of Dentistry Research Center, King Saud University, Riyadh, Kingdom of Saudi A...