Why we should care about soft tissue interfaces when applying ultrasonic diathermy: an experimental and computer simulation study.

BACKGROUND: One goal of therapeutic ultrasound is enabling heat generation in tissue. Ultrasound application protocols typically neglect these processes of absorption and backscatter/reflection at the skin/fat, fat/muscle, and muscle/bone interfaces. The aim of this study was to investigate the heating process at interfaces close to the transducer and the bone with the aid of computer simulation and tissue-mimicking materials (phantoms). METHODS: The experimental setup consists of physiotherapeutic ultrasound equipment for irradiation, two layers of soft tissue-mimicking material, and one with and one without an additional layer of bone-mimicking material. Thermocouple monitoring is used in both cases. A computational model is used with the experimental parameters in a COMSOL® software platform. RESULTS: The experimental results show significant temperature rise (42 °C) at 10 mm depth, regardless of bone layer presence, diverging 3 °C from the simulated values. The probable causes are thermocouple and transducer heating and interface reverberations. There was no statistical difference in the experimental results with and without the cortical bone for the central thermocouple of the first interface [t(38) = -1.52; 95% CI = -0.85, 0.12; p = 14]. Temperature rise (>6 °C) close to the bone layer was lower than predicted (>21 °C), possibly because without the bone layer, thermocouples at 30 mm make contact with the water bath and convection intensifies heat loss; this factor was omitted in the simulation model. CONCLUSIONS: This work suggests that more attention should be given to soft tissue layer interfaces in ultrasound therapeutic procedures even in the absence of a close bone layer.

Prevalence of talon cusps in a Portuguese population: Forensic identification significance of a rare trait.

BACKGROUND: Dental techniques are frequently used in human identification; some of those include comparative analyses of dental features that, being rare or unique to an individual, can establish a positive identification. The usefulness of each feature depends on its population, frequency, and uniqueness. The aim of this study was to determine the prevalence of talon cusps in a Portuguese population. MATERIALS AND METHODS: A prospective study was performed. Three hundred and two patients were studied, and talon cusps presence was assessed. Statistical tests were carried out using Statistical Package for the Social Sciences (SPSS) 17 software (SPSS Inc., Chicago, IL, USA). Statistical analysis relied primarily on descriptive statistics and crosstabs, with Chi-square analysis. RESULTS: Results showed that talon cusps were observed in only 6.3% of patients. The maxillary lateral incisors were the most common teeth showing this feature (82.1% of all teeth). CONCLUSION: It can be concluded that talon cusps are an uncommon trait in these Portuguese population, and therefore, it is a feature that can be potentially very useful in forensic human identification, when antemortem dental records are available.

Infecções por Candida spp na Cavidade Oral / Oral infections by Candida spp

As Candida spp são a causa mais frequente de infecções fúngicas humanas. A espécie mais prevalente, a C. albicans, sendo um importante microrganismo comensal da cavidade oral, em determinadas condições, torna-se patogênica, aparecendo associada a várias situações patológicas. Neste artigo, pretende-se fazer uma revisão bibliográfica sobre infecções orais por Candida spp (Candidoses), apresentando a sua classificação, diferentes formas clínicas, diagnóstico e tratamento. Referem-se, ainda, outras patologias que frequentemente surgem associadas a essas infecções.

Human yeast infections are mainly caused by Candida spp. C. albicans is the most common specie and an important commensal microorganism of the oral cavity but in certain conditions becomes pathogenic, appearing associated to several pathological situations. With this article the authors intend to do a revision of oral infections by Candida spp (Candidosis), presenting its classification, different clinical forms, diagnosis and treatment. Other pathologies that frequently appear associated to these infections are also referred.

Chronological age estimation based on third molar development in a Portuguese population.

Third molar development was assessed using a sample of 1,131 orthopantomograms from a Portuguese population. The methodology applied was the eight stages (A-H) method described by Demirjian et al. The final sample was made of 739 orthopantomograms, 387 (52.5%) of which belonging to females; age ranged between 6.1 and 22.5 years old (mean age = 14.49, S.D. = 4.37). For each developmental stage, mean age, standard deviation, and minimal and maximal age was assessed; evaluation of the rate formation of each tooth, according to sex, was calculated and data distribution expressed in percentiles for each stage; the probability of an individual being 16 was also evaluated. The relationship between tooth development and chronological age had a statistical significance for all teeth and both sexes (p < 0.0001). The data described may provide reference for forensic application and agree with the thesis that each population need specific data.