Panoramic dental X-ray exposure leads to oxidative stress, inflammation and apoptosis-mediated developmental defects in zebrafish embryos.

Panoramic x-ray units are widely used in dental radiodiagnostics. Patients are exposed to relatively low radiation doses with panoramic imaging, but considering lifetime frequency of exposure, even a small risk can have serious health consequences. Our aim was to assess the effects of panoramic x-rays at two different exposure times on developing zebrafish embryos, focusing on oxidative stress, inflammation, apoptotic pathways, and development. Zebrafish embryos were divided into three groups: control, standard panoramic (SPE, 5.5 s exposure time) and pedodontic panoramic x-ray group (PPE, 4.8 s exposure time). Optically stimulated luminescence dosimeters were used to measure absorbed doses. Mean radiation doses for SPE and PPE were 7.83 mSv and 5.83 mSv respectively. At the end of 96 h post-fertilization, lipid peroxidation (LPO), nitric oxide (NO), reduced glutathione (GSH), glutathione S-transferase and superoxide dismutase were measured in the embryos. Expressions of genes related with inflammation (tnfα, il6, ill15, il21), immunoregulation (ifng) and apoptosis (p53, bax, casp2, casp3, casp8) were determined by RT-PCR. Even at reduced doses at high-speed mode, developmental toxicity was observed in both groups as evidenced by decreased pigmentation, yolk sac oedema, and spinal curvature. While deterioration of oxidant-antioxidant balance, suppression of immune response, induction of inflammation and apoptosis were observed through increased LPO, NO, decreased GSH, ifng, and increased expressions of genes related with inflammation and apoptosis, these effects were more pronounced in the SPE group. These results demonstrate the influence of exposure time and indicate the need for further consideration of optimal panoramic modes from a radiation-induced damage perspective.

Association between second mesiobuccal canal and apical periodontitis in retrospective cone-beam computed tomographic images.

This retrospective cone-beam computed tomography study aimed to investigate the possible associations of apical periodontitis (AP) with missed/unmissed second mesiobuccal (MB2) canals. MB2 canals and AP were investigated in 257 endodontically treated and 673 untreated maxillary molars, and the former were analyzed regarding missed/unmissed MB2 canals. The chi-squared test and odds ratio (OR) were used for statistics. The prevalence of MB2 canals in maxillary first molars was higher than that in second molars (p = 0.001). MB2 canals were 1.751 times more common in males than in females (OR: 1.751; 95% CI: 1.334-2.297), with a significant difference in the 18-39 age groups (p = 0.005). The risk for AP was 5.5 times greater in endodontically treated maxillary molars with missed MB2 canals than in those with unmissed MB2 canals (p = 0.012) (OR: 5.5, 95% CI: 1.549-19.527). The findings of this study reveal that the likelihood of the MB2 canal is higher in the maxillary first molars of young adult males.

Associations between Periapical Health of Maxillary Molars and Mucosal Thickening of Maxillary Sinuses in Cone-beam Computed Tomographic Images: A Retrospective Study.

INTRODUCTION: This retrospective study aimed to assess the radiologic characteristics of the possible associations between mucosal thickening of the maxillary sinuses (MSs) and periodontal and anatomic conditions of healthy and diseased maxillary teeth. METHODS: The periapical health of the maxillary molars in cone-beam computed tomographic (CBCT) images from 50 patients (mean age = 40.60±14.59 years) was evaluated using the CBCT-periapical index. Anatomic associations between maxillary molars and the inferior wall of the MSs and periodontal bone loss and its relation to MS pathology were assessed. The possible effects of these conditions on mucosal thickening of MSs were analyzed. Kruskal-Wallis, Mann-Whitney U, chi-square, and logistic regression (for relative risk) tests were used for statistical analysis. RESULTS: CBCT-periapical index 4 was the most frequently encountered apical periodontitis (AP) lesion. The risk for pathologic changes in the MSs was significantly higher in the presence of AP (P < .001). This risk was 62.364 times greater than that in areas of MSs adjacent to healthy teeth of the same patient (95% confidence interval, 7.968-488.14). Thicker MS mucosae were detected when the molar roots with AP were closer to the MSs (P < .004). No statistically significant difference was found between periodontal status and MS pathology. CONCLUSIONS: The findings of this study showed that MSs were affected by the endodontic health of adjacent molar teeth. Dental and medical practitioners should take into consideration the possible odontogenic causes while examining pathologic changes in the MS.

Association between Oral Mucosal Lesions and Hygiene Habits in a Population of Removable Prosthesis Wearers.

PURPOSE: This prospective study evaluated the influence of self-reported prosthesis hygiene regimens and prosthesis usage habits on the presence of oral mucosal lesions (OMLs) in complete removable and/or partial removable dental (CRDP/PRDP) prosthesis wearers (PWs). MATERIALS AND METHODS: Between January 2009 and January 2011, the conventional oral mucosa of 400 consecutive PWs (252 women; 148 men), aged between 29 and 86 years, were examined clinically. Information was derived considering the type and age of the prosthesis, hygiene level, frequency and style of prosthesis cleaning, overnight prosthesis use, storage conditions, and systemic diseases. Non-prosthesis- and prosthesis-related OMLs were identified. The data were analyzed using univariate (Chi-square) and multivariate (logistic regression) tests to assess the development of OMLs as a function of the selected variables. Odds ratios (OR) were calculated at 95% confidence intervals (CI; α = 0.05). RESULTS: Of the 400 PWs, 21.5% had CRDP, 52.5% PRDP, and 25.8% CRD/PRD prostheses. Thirty-two percent of the PWs cleaned their prosthesis once a day. Brushing the prosthesis with toothbrush and soap/toothpaste was the most commonly practiced cleaning regimen (85.8%). More than half (64.5%) of the PWs used their prosthesis overnight. Among all PWs, 37.8% had a prosthesis-related OML. Stomatitis Newton Type II (46%) and Type III (38%) were the most common OMLs. OML frequency was higher in PWs having CRDPs than those having PRDPs (p < 0.05). Overnight prosthesis use (p = 0.003, OR: 13.65; 95% CI: 1.7-109.3), denture age ≥11 years (p = 0.017, OR: 1.72; 95% CI: 1.1-2.7), and immersion in water and solution (p = 0.023, OR: 1.13; 95% CI: 0.02-1.02) affected the incidence of OML significantly. Hypertension was the most common systemic disease (31.5%). CONCLUSION: Overnight use, denture age, and storage conditions of CRDP or PRDPs demonstrated a more significant impact on OML incidence than frequency of cleaning. Oral healthcare programs for removable PWs should specifically provide education on prosthesis usage instructions.