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Objective@#This study was conducted to compare changes in pharyngeal airway after different orthognathic procedures in subjects with class III deformity. @*Methods@#The study included CBCT scans of 48 skeletal class III patients (29 females and 19 males, mean age 23.50 years) who underwent orthognathic surgery in conjunction with orthodontic treatment. The participants were divided into three groups of 16, as follows: Group 1, mandibular setback surgery; group 2, combined mandibular setback and maxillary advancement surgery; and group 3, maxillary advancement surgery. CBCT images were taken 1 day before surgery (T0), 1 day (T1), and 6 months (T2) later. The dimensions of the velopharynx, oropharynx, and hypopharynx were measured in CBCT images. @*Results@#In all groups, there was a significant decrease in airway variables immediately after surgery, with a significant reversal 6 months later (P < 0.05). In subjects who underwent maxillary advancement, the airway dimensions were significantly greater at T2 than the T0 time point (P < 0.05), whereas in the mandibular setback and bimaxillary surgery groups, the T2 values were lower than the baseline examination (P < 0.05). The alterations in airway variables were significantly different between the study groups (P < 0.05). @*Conclusions@#The mandibular setback procedure caused the greatest reduction in the pharyngeal airway, followed by the bimaxillary surgery and maxillary advancement groups, with the latter exhibiting an actual increase in the pharyngeal airway dimensions. It is recommended to prefer a two-jaw operation instead of a mandibular setback alone for correction of the prognathic mandible in subjects with predisposing factors to the development of sleep-disordered breathing.
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Statement of the Problem: Tonsilloliths are relatively common clusters of dystrophic calcified material that form in the tonsillar crypts, mostly the palatine tonsils. Although they may be asymptomatic, some cause halitosis, cough, dysphagia, and foreign body sensation, as well as otalgia. Since tonsilloliths can be detected on panoramic views as radiopaque lesions, and misdiagnosis may lead to wasting time and cost, dentist should be familiar with radiographic characteristics of this type of calcification.
Purpose: This study was conducted to determine the prevalence and the pattern of distribution of tonsilloliths on panoramic radiographs.
Materials and Method: This cross-sectional study was based on 2000 panoramic radiographs from 1030 female and 970 male aged 6-75 years old evaluated for the presence and pattern of tonsillolithiasis, between 2011 and 2013 in Shiraz, Iran. Chi- square test and odds ratio were used to evaluate the relationship between tonsillolithiasis and gender. p< 0.05 was considered as statistically significant
Results: Out of the 2000 individuals, 101 cases [5.05%] had tonsilloliths on panoramic radiographs out of which 61 were male [60.4%] and 40 were female [39.6%], with age range of 18 to 65. Forty patients [39.6%] had both left and right sides involved, 25 of tonsilloliths [24.75%] were located on the right and 36 on the left side [35.65%]. Men were more likely to develop tonsilloliths [p= 0.014]
Conclusion: Tonsilloliths are not very common finding and can be detected on nearly 5.05% of panoramic radiographs. Most of the cases are unilateral with a diameter less than 2mm
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The preparation of the root canal space includes debridement, shaping and apical preparation. These procedures are challenging and constitute. The recent introduction of automated techniques for canal preparation has created considerable interest. The aim of this study was to test shaping ability of one hand instrumentation [passive step-back technique] and new rotary NiTi system [Mtwo instrumentation] in curved root canals. A total number of 40 curved molars selected for this in vitro study, 20 canals for each group. The mean of canal curvature in studied groups was similar. After preparation of access cavity, samples were divided into two groups. A custom made block was used for standardization of radiograph beam angel before and after preparation. In group 1, samples instrumented with passive step-back technique using stainless steel K-file, Gates Glidden and Pesso reamers. Mtwo NiTi rotary file and Endo IT power driven motor were used for instrumentation of samples in group 2. Transportation of canals curvature [loss of primary curvature] after canal preparation was assessed for each sample with the aid of AutoCAD 2007 software. Stereomicroscope provided data for measurement of changes in working length after canal preparation. The mean of changes in canals curvature [canal transportation] and mean of working length changes in group 1 [passive step-back technique] were 11.77 degree and 0.202 mm [P