ABSTRACT
ABSTRACT: The objective this study was to determine mean values of masseter muscle thickness in male and female, at rest and contraction, in healthy individuals. At first, 102 questionnaires were distributed between students. Thirty patients were selected, 15 male and 15 female, according to the inclusion criteria, excluding all individuals with symptoms of temporo-mandibular dysfunction or syndromes with craniofacial disorders. Masseter muscle thickness was determined bilaterally, at rest and contraction. As a reference point for the measurement of thickness (axial plane), the posterior prolon gation of the labial commissure was used. Normality values of the masseter muscle in females were 11.75 ± 1,14 mm in contraction and 10.19 ± 1.04 mm in relaxation; and in the male were 13.95 ± 1.62 mm in contraction and 11.64 mm ± 1.68 mm in relaxation. The results obtained are in agreement with those described in the literature. Demonstrating the accuracy and reproductibility of the ultrasound if a protocol is applied, mainly aimed at controlling the pressure applied by the transducer.
RESUMEN: El objetivo de este estudio fue determinar los valores medios del grosor del músculo masetero, en reposo y contracción, en hombres y mujeres sanos. Inicialmente se distribuyeron 102 cuestionarios entre los estudiantes. Se seleccionaron 30 pacientes, 15 hombres y 15 mujeres, según los criterios de inclusión, excluyendo a todos los individuos con síntomas de disfunción temporo-mandibular o síndromes con alteraciones craneofaciales. El grosor del músculo masetero se determinó de forma bilateral, en reposo y contracción. Como punto de referencia para la medición del espesor (plano axial), la prolongación posterior de la comisura labial. Los valores de normalidad del músculo masetero en las mujeres fue de 11,75 ± 1,14 mm en contracción y 10,19 ± 1,04 mm en relajación; y en los varones 13,95 ± 1,62 mm en contracción y 11,64 mm ± 1,68 mm en relajación. Los resultados obtenidos coinciden con los descritos en la literatura, señalando la precisión y reproducibilidad del ultrasonido si se aplica un protocolo, principalmente dirigido a controlar la presión aplicada por el transductor.
ABSTRACT
OBJECTIVES: This study aims to determine if there are enough buccal alveolar bone thickness to perform an immediate dental implant placement in anterior and posterior maxillary teeth. MATERIAL AND METHODS: A total of 1463 teeth were examined, from 202 cone-beam computed tomography scans with voxel sizes of 0.15 mm. On each tooth, the following measures were determined: the alveolar bone thickness in two locations; the vertical distance between the buccal alveolar crest and cementoenamel junction; the angle between the tooth's long axis and the alveolar bone axial inclination in the sagittal plane. RESULTS: In the most coronal location of maxillary teeth, the thickness of alveolar bone was lower than 0.6 (SD 0.6) mm in 50% of the teeth, and in the middle of the root the bone thickness was, on average, 0.96 (SD 0.6) mm. For the same maxillary teeth, the vertical distance between the buccal alveolar crest and cementoenamel junction and the angulation measured were, on average, 3.6 (SD 1.2) mm and 12.1º (SD 1.4º), respectively. CONCLUSIONS: The present study revealed that in most cases the thickness of buccal alveolar bone was less than 1 mm. Consequently, in such cases, immediate dental implant placement operation is not recommended, or should be combined with bone regeneration techniques.
ABSTRACT
The aim of this study was to systematically review the existing scientific literature and evidence about (a) the validation of masseter muscle ultrasonography for accurate assessment of muscle thickness and (b) the reproducibility of masseter muscle thickness measures. An electronic literature search was conducted using determined keywords on specific databases. Preliminary search revealed 298 articles listed in Medline, Scopus and Web of Science. 60 duplicates were rejected, leaving 238 articles for review. After reading titles and abstracts, 31 articles remained. 23 articles were assessed for eligibility. These articles were categorized as follows: thickness, cross-section, volume and the length of the masseter muscle measured by ultrasonography. It is possible to verify the thickness of the masseter muscle in males and females in relaxation (10-15 and 9-13 mm, respectively) and contraction (14-19 and 12-15 mm, respectively). A similar tendency can also be evidenced in other measurements. Many studies evaluate masseter muscle dimensions to relate it to cephalometric analysis as such to evaluate morphological variations. It can be concluded that ultrasound is a reliable clinical tool for masseter muscle measurements, yet there is a need for standardization of methods and parameters to be recorded.
