Journal of Dental Medicine

Background and Aims: All metal components of orthodontic appliances are somewhat corroded in the oral environment due to some changes in chemical, mechanical, thermal, microbiological and enzymatic factors which facilitates ion release. Ionic release can result in a discoloration of the surrounding soft tissue or allergic reactions in sensitive patients or even local pain in the area. In general, ions can cause toxic and biological side effects if their values reach the threshold, so the release of ions from the metal components of orthodontic appliances is important to us. The aim of this review article to determine the rate of orthodontic appliances ion release in different solutions.
Materials and Methods: A review of the literature was carried out in Pubmed, Google Scholare and Web of science database using selected key words (Saliva/ Titanium/Normal Saline/ Ion release Orthodontic appliance/Mouth wash/ Nickel/ Chromium). These searches were limited to the articles published from 2005 to 2018. According to the inclusion and exclusion criteria, 25 articles were obtained.
Results: Because of conflicts in the reported results, it was necessary to synchronize the measurement methods and also to use artificial saliva medium with normal pH as a control to achieve better systematic comparison.
Conclusion: There was significant differences in the ion release between mouthwashes. In all studies, the effect of pH and acidity has been shown to increase the release of these ions. In addition, stainless steel (SS) instruments had the least biocompatibility among all types of alloys evaluated.

Background and Aims: Third molar teeth extraction is one of the common treatments procedure in dentistry. The proximity of mandibular third molar teeth to the inferior alveolar nerve canal may make the surgery challenging and cause adverse complications. The purpose of this study was to determine the accuracy of diagnostic and evaluation of panoramic radiography findings in two classification methods (Rood-Shehab and Tanaka) according to CBCT in mandibular third molar extraction surgery.
Materials and Methods: This cross-sectional analytical study was conducted on 65 patients of a private radiology clinic in Qom who had simultaneous panoramic and CBCT radiography. Panoramic and CBCT radiographs were imported into Scanora and Ondemand softwares, respectively. The relation of the mandibular third molar with the inferior alveolar nerve was evaluated according to Tanaka's classification and Rood-Shehab radiographic signs and compared with CBCT radiographs. Finally, the obtained data were analyzed by chi-square test, ROC curve and SPSS software version 24. The significant level was considered at P<0.05.
Results: Out of 65 samples, 23.1% were men and 76.9% were women. The mean age of participants was 26.9±8.77. There was a significant relation between the Tanaka's classification of panoramic radiographs and proximity to the nerve in CBCT radiographs (P=0.011). This relationship was significant when the number of radiographic signs of the Rood-Shehab classification increased (P=0.044). Root darkening and diversion of mandibular nerve canal signs of Rood-Shehab classification showed more diagnostic accuracy in the nerve canal contact determination than that of other signs.
Conclusion: The probability of contact of third molar root with the inferior alveolar nerve canal increases with increasing in the number of Rood-Shehab radiographic signs. The root darkening sign was more accurate and followed by mandibular canal diversion sign. Tanaka’s classification can be used in differentiating cases without contact to the nerve canal.