Jose Antonio Bosio

There is a critical need for an accurate device for orthodontists to know the magnitude of forces exerted on the tooth by the orthodontic brackets. Here, we propose a new orthodontic force measurement principle to detect the deformation of the elastic semi-sphere sensor. Specifically, we aimed to detail technical issues and the feasibility of the sensor performance attached to the inner surface of the orthodontic aligner or on the tooth surface. Accurate force tracking is important for the optimal decision of aligner replacement and cost reduction. A finite element (FE) model of the semi-sphere sensor was developed, and the relationship between the force and the contact area change was investigated. The prototype was manufactured, and the force detection performance was experimentally verified. In the experiment, the semi-sphere sensor was manufactured using thermoplastic polymer, and a high-precision mold sized 3 mm in diameter. The change in the contact area in the semi-sphere sensor was captured using a portable microscope. Further development is justified, and future implementation of the proposed sensor would be an array of multiple semi-sphere sensors in different locations for directional orthodontic force detection.

The aims of this study were to evaluate U.S. and Canadian orthodontic faculty members’ degree of job satisfaction and to assess the relationship between job satisfaction and factors such as full-time/part-time status, tenure status, age, and teaching training. This information is needed to set long-term goals for improving the recruitment and retention of full-time and part-time faculty. In August 2016, all members of the Council on Orthodontic Education Society of Educators and faculty members of the American Association of Orthodontists were invited via email to participate in a 34-question survey, which collected demographic data and asked respondents to report their degree of satisfaction on seven factors. Out of 645 individuals invited to participate, 133 completed all items on the survey (response rate 20.6%). The results showed that faculty time commitment, rank/position in the institution, and tenure status affected respondents’ levels of satisfaction regarding quantity of clinical time, value placed on teaching by their institution and students, and leadership of their department chair. In the open-ended responses, increased compensation, more teaching time, and less administrative activity were the most frequent recommendations to improve satisfaction levels. About half (52%) of the respondents reported being satisfied with their financial compensation. Respondents whose institutions gave them training opportunities in teaching skills were 4.78 times more satisfied than those not given those opportunities. The results suggest that reduction of administrative workload, creation of meaningful faculty development programs, more feedback and sharing of information about requirements for promotion, and improvement of financial compensation could improve recruitment and retention of orthodontic educators.

Toll-like receptor 4 (TLR-4) is a transmembrane protein involved in the innate immune system and has been implicated in the pathogenesis of temporomandibular joint dysfunction (TMD). The purpose of this study was to histologically examine the level of expression of TLR-4 relative to severity of TMD. Thirty-one human TMJ disc samples were immunostained for TLR-4 and evaluated for intensity of stain. Among the samples, 8 were control samples, 16 were from patients with anterior disc displacement with reduction (ADDwR), and 7 were from patients with anterior disc displacement without reduction (ADDwoR). There was no statistically significant difference in intensity of stain between groupings (p = 0.673). The results indicate a negative correlation between TMD and the expression of TLR-4.

Objective: To investigate the association between tooth loss and craniofacial factors with changes in mandibular condylar morphology. Methods: A total of 123 patients participated in this cross-sectional study. The mandibular condylar morphology was evaluated using digital panoramic radiography. The exposure variables included gender, age group, molar relationship, facial growth pattern, facial asymmetry, dental midline, posterior crossbite, presence of fixed dental prosthesis, and tooth loss. Results: Unilateral and bilateral mandibular condyle structural alterations were found in 20.3% and 28.5% of the sample, respectively. After the adjustment analysis, posterior crossbite (adjusted OR = 3.34, 95% CI = 1.23–9.06) and tooth loss (adjusted OR = 4.08, 95% CI = 1.72–9.64) were associated with the outcome. The tooth type associated with mandibular condyle structural alterations were premolars and upper molars. Conclusion: The findings suggest that posterior crossbite and tooth loss are associated with mandibular condyle structural alterations.