Electromyographic Patterns and the Identification of Subtypes of Awake Bruxism.

The future of awake bruxism assessment will incorporate physiological data, possibly electromyography (EMG) of the temporal muscles. But up to now, temporal muscle contraction patterns in awake bruxism have not been characterized to demonstrate clinical utility. The present study aimed to perform surface EMG evaluations of people assessed for awake bruxism to identify possible different subtypes. A 2-year active search for people with awake bruxism in three regions of the country resulted in a total of 303 participants (223 women, 38 ± 13 years, mean and SD). Their inclusion was confirmed through non-instrumental approaches for awake bruxism: self-reported questionnaire and clinical exam, performed by three experienced and calibrated dentists (Kappa = 0.75). Also, 77 age- and sex-matched healthy controls were recruited (49 women, 36 ± 14 years). Temporalis surface EMG was performed with a portable device (Myobox; NeuroUp, Brazil). EMG signals were sent to a computer via Bluetooth 4.0 at a sampling rate of 1,000 Hz. Digital signal processing was performed using the commercial neuroUP software, transformed in RMS and then normalized for peak detection (EMG peaks/min), in a 10 min session. Cluster analysis revealed three distinct subtypes of awake bruxism: phasic, tonic, and intermediate. Individuals with a predominance of EMG peaks/min were classified as the "phasic" subtype (16.8%). Those with the highest EMG rest power were classified as the "tonic" subtype (32.3%). There was also an "intermediate" subtype (50.8%), when both variables remained low. Characterization of awake bruxism physiology is important for future establishment of instrumental assessment protocols and treatment strategies.

Knowledge and Attitudes of Primary Health Care Dentists Regarding Oral Cancer in Brazil.

OBJECTIVE: The aim of this study was to evaluate the knowledge and attitudes of dentists working in Primary Health Care Units from a Brazilian city, regarding oral cancer. MATERIALS AND METHODS: A prospective, cross-sectional, epidemiologic survey was performed. Seventy-one dentists from Primary Health Care Units were contacted at their workplace, and participated of the study. Data were collected through a self-administered questionnaire of 31 multiple-choice questions addressing the main clinical features and risk factors for oral cancer. The questionnaire was divided into two sections: questions related to general data and self-perception of the participants regarding personal knowledge of oral cancer, and objective questions related to general information on oral cancer (clinical features, characteristics, traits, and risk factors). The data were tabulated and analyzed by descriptive statistics. RESULTS: Participants were mostly females (81.5%), less than 40 years of age (57.7%), who underwent training 10-20 years ago (47.9%). Most respondents (66.2%) considered their level of knowledge about oral cancer to be satisfactory. However, only 26.8% of tem felt that they were able to carry out diagnostic procedures for oral cancer. Most of them (95.8%) were interested in participating in training courses on Oral Diagnostics; 56.3% of them reported not having received any training or guidance on how to conduct an examination to detect oral cancer during undergraduate training. CONCLUSIONS: These findings are consistent with previous reports and point to the need for new public policies to enable early diagnosis of oral cancer and a review of training in Oral Diagnostics in dental schools.

Human identification study by means of frontal sinus imaginological aspects.

The objective of this study was to evaluate the applicability of human identification parameters, established by Tatlisumak et al. (2007), by means of cone-beam computed tomography and extraoral radiographs of the frontal sinus region. From a total of 58 dry skulls, 26 were selected. Posteroanterior, profile cephalometric radiographs and cone-beam computed tomography images were acquired, adopting a specific method for reproducibility purposes. The images were evaluated by two examiners, previously calibrated, in a darkened environment and at two distinct sessions, with a minimum of 15 days between them. The characteristics of the frontal sinus were analyzed using the Cohen's kappa test, for categorical variables, and Lin's concordance correlation coefficient (CCC) for continuous variables. Acceptable values of inter method variability for the categorical variables were found, while same cannot be told for continuous variables. The parameters evaluated for the frontal sinus on extraoral radiographs and cone-beam computed tomographs were mostly concordant, with the exception of three. Categorical and discrete variables showed an intra- and interexaminer concordance ranging from good to perfect, and the quantitative continuous variables showed concordance ranging from moderate to excellent. The parameters examined are applicable and reproducible using multiplanar reconstructions of cone-beam computed tomography and extraoral radiographs of the frontal sinus.

Evaluation of third molar development in the estimation of chronological age.

The purpose of this study was to evaluate the correlation between chronological age and the degree of third molar mineralization by Demirjian's developmental stages (Demirjian et al., 1973) using panoramic radiography. From a total of 11.396 digital panoramic radiographs of patients from three oral radiology private clinics from the northeast region of Brazil, obtained from January to June 2009, 2097 radiographic images from patients aged between 6 and 22 years were selected. The images were analyzed individually by two obsevers using a 21-inch computer screen and Windows Picture and Fax Viewer. Reliability was achieved by intra- and interobserver evaluation, using the Kappa test. Chronological age, calcification stage, gender and third molar were interrelated using a multiple linear regression model, considering age as a response variable. There was reliability with Demirjian et al.'s developmental stage assesment, displaying a significant relationship between mineralization stages and patients' age (P<0.05). There was no significant difference between the average age and the calcification stage taking gender and localization of the third molar into consideration. It is possible to estimate chronological age based on Demirjian's stage of a third molar, regardless of gender and location.