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Objective : The maxilla is formed by the medial nasal and maxillary processes fusion. The dental lamina develops from 2 origins connecting in the lateral incisor. The maxillary lateral incisor region is often affected by dental anomalies and clefting. It is possible that genes involved in oral cleft could also be associated with a variety of phenotypic variations in the maxillary lateral incisor. In this phenotype–genotype study, we explored the association between polymorphisms in the oral-cleft-related genes BMP2 and BMP4 and root curvature of maxillary lateral incisors. Design : Cross-sectional study. Settings : Universities and private clinics. Patients, Participants : Panoramic radiographs and DNA from 231 patients were analyzed. Main Outcome Measures : Schneider method (1971) was applied to estimate the degree of root curvature of the maxillary lateral incisors and to classify the root as straight (5° or less) or curved (higher than 5°). Genetic polymorphisms in BMP2 (rs235768 and rs1005464) and BMP4 (rs17563) were genotyped. Statistical analysis was performed. Results : A total of 401 teeth (199 left and 202 right) were evaluated. Genetic analysis demonstrated trends toward association for the rs1005464 in BMP2 (P =.025) in co-dominant model and in dominant model (P =.026) for left incisors. The rs235768 in BMP2 showed trends toward association with the degree of root curvature in left incisors in the recessive model (P =.031). rs17563 in BMP4 also showed trends toward association with the degree of the root curvature in left incisors (P =.019). Conclusion : BMP2 (rs235768 and rs1005464) and BMP4 (rs17563) might be involved in maxillary lateral incisor root curvature. [ABSTRACT FROM AUTHOR]

We investigated the physical properties of head and neck cancer cells to develop new cell-selective treatment strategies for squamous cell carcinoma. For better characterization and subsequent differentiation of cancerous and healthy cells, we developed MATLAB-based software to analyze image stacks obtained using a confocal laser-scanning microscope. A confocal laser-scanning microscope was used for three-dimensional (3-D) imaging of a cell line from the head and neck area. The volume of cell organelles of interest was calculated using our newly developed software. Our software enables 3-D visualization and volume calculation as well as data analysis associated with cell morphology. Using filter and semi-automatic segmentation algorithms, our software recognizes individual cell organelles in each slice of an image stack. It matches the corresponding cell cross section areas to produce a 3-D image and to determine the volume of the imaged organelles. We calculated the volume of the nucleus, actin filaments and microtubules in relation to total cell volume. Our software enables 3-D visualization and calculation of organelle volume, which improves cell characterization and comparison of healthy and cancerous cell lines. Differences between cell lines can be observed in detail and used to develop new cancer treatment strategies. [ABSTRACT FROM AUTHOR]

Background In orthodontic tooth movement (OTM), pseudo-inflammatory processes occur that are similar to those of nicotine-induced periodontitis. Previous studies have shown that nicotine accelerates OTM, but induces periodontal bone loss and dental root resorption via synergistically increased osteoclastogenesis. This study aimed to investigate the role of hypoxia-inducible factor 1 alpha (HIF-1α) in nicotine-induced osteoclastogenesis during OTM. Materials/Methods Male Fischer-344 rats were treated with l -Nicotine (1.89 mg/kg/day s.c. N = 10) or NaCl solution (N = 10). After a week of premedication, a NiTi spring was inserted to mesialize the first upper left molar. The extent of dental root resorption, osteoclastogenesis, and HIF-1α protein expression was determined by (immuno)histology, as well as bone volume (BV/TV) and trabecular thickness (TbTh) using µCT. Receptor activator of nuclear factor of activated B-cells ligand (RANK-L), osteoprotegerin (OPG), and HIF-1α expression were examined at the protein level in periodontal ligament fibroblasts (PDLF) exposed to pressure, nicotine and/or hypoxia, as well as PDLF-induced osteoclastogenesis in co-culture experiments with osteoclast progenitor cells. Results Nicotine favoured dental root resorptions and osteoclastogenesis during OTM, while BV/TV and TbTh were only influenced by force. This nicotine-induced increase does not appear to be mediated by HIF-1α, since HIF-1α was stabilized by force application and hypoxia, but not by nicotine. The in vitro data showed that the hypoxia-induced increase in RANK-L/OPG expression ratio and PDLF-mediated osteoclastogenesis was less pronounced than the nicotine-induced increase. Conclusions Study results indicate that the nicotine-induced increase in osteoclastogenesis and periodontal bone resorption during OTM may not be mediated by hypoxic effects or HIF-1α stabilization in the context of nicotine-induced vasoconstriction, but rather by an alternative mechanism. [ABSTRACT FROM AUTHOR]

The maxilla is formed by the medial nasal and maxillary processes fusion. The dental lamina develops from 2 origins connecting in the lateral incisor. The maxillary lateral incisor region is often affected by dental anomalies and clefting. It is possible that genes involved in oral cleft could also be associated with a variety of phenotypic variations in the maxillary lateral incisor. In this phenotype-genotype study, we explored the association between polymorphisms in the oral-cleft-related genes BMP2 and BMP4 and root curvature of maxillary lateral incisors., Cross-sectional study., Universities and private clinics., Panoramic radiographs and DNA from 231 patients were analyzed., Schneider method (1971) was applied to estimate the degree of root curvature of the maxillary lateral incisors and to classify the root as straight (5° or less) or curved (higher than 5°). Genetic polymorphisms in BMP2 (rs235768 and rs1005464) and BMP4 (rs17563) were genotyped. Statistical analysis was performed., A total of 401 teeth (199 left and 202 right) were evaluated. Genetic analysis demonstrated trends toward association for the rs1005464 in BMP2 ( P   =  .025) in co-dominant model and in dominant model ( P   =  .026) for left incisors. The rs235768 in BMP2 showed trends toward association with the degree of root curvature in left incisors in the recessive model ( P   =  .031). rs17563 in BMP4 also showed trends toward association with the degree of the root curvature in left incisors ( P   =  .019)., BMP2 (rs235768 and rs1005464) and BMP4 (rs17563) might be involved in maxillary lateral incisor root curvature., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.