Comparison reproducibility between the facebow and a new technique based on a spirit level device.

Objective: This study aimed to introduce a spirit level device for mounting maxillary casts to compare the reproducibility between the facebow and this new technique.Methods: The maxillary casts of 10 participants were mounted in three different situations: 1) with the facebow; 2) with the spirit level device, the participant in seated position; and 3) with the spirit level device with participant in standing position. Each procedure was performed by three different evaluators. The values obtained were calculated using the Technical Error of Measurement (TEM) and the inter-evaluator Coefficient of Variation (CV).Results: The mean values obtained were 4.3 mm, 2.2 mm, and 2.6 mm for absolute TEM; 8.7%, 5.4%, and 6.4% for relative TEM; and 7.3%, 4.5%, and 5.6% for CV.Conclusion: These results show that the facebow is less reproducible compared to the new device, demonstrating that the new technique can be satisfactorily used in clinical practice.

Analysis of the stomatognathic system of children according orthodontic treatment needs.

PURPOSE: The present study evaluated electromyographic activity (EMG), masticatory performance, and tongue strength in children without and with orthodontic treatment needs. PATIENTS AND METHODS: A total of 90 children were screened and divided into the following groups: Group I (no treatment needed; mean age: 8.00 ± 0.43 years; n = 26), Group II (few malocclusions, treatment needed; mean age: 8.89 ± 0.43 years; n = 28), and Group III (slight-to-borderline treatment needed; mean age: 8.44 ± 0.22 years; n = 36). Orthodontic treatment need was classified on the basis of IOTN-DHC (Index of Orthodontic Treatment Need - Dental Health Component). The electromyographic Trigno EMG Systems was used for muscle analysis and the Iowa Oral Pressure Instrument (IOPI) was used to measure tongue strength. Data were analyzed using normality tests and one-way analysis of variance with a Bonferroni post hoc test (p ≤ 0.05). RESULTS: EMG in almost all mandibular movements was higher in Group III with statistically significant differences compared to position at rest: right masseter (p = 0.03); protrusion: left temporal (p = 0.02); saliva swallowing: left temporal (p = 0.05) and water swallowing: orbicularis oris mouth, right upper segment (p = 0.05). Lower masticatory performance was found in Group III, but the difference compared to Group I and II was not significant. There were no significant differences between the groups in terms of tongue strength. CONCLUSIONS: Children with borderline orthodontic treatment needs show functional disorders of the stomatognathic system.

The effect of a Lucia jig for 30 minutes on neuromuscular re-programming, in normal subjects

The Lucia jig is a technique that promotes neuromuscular reprogramming of the masticatory system and allows the stabilization of the mandible without the interference of dental contacts, maintaining the mandible position in harmonic condition with the musculature in normal subjects or in patients with temporomandibular dysfunction (TMD). This study aimed to electromyographically analyze the activity (RMS) of the masseter and temporal muscles in normal subjects (control group) during the use of an anterior programming device, the Lucia jig, in place for 0, 5, 10, 20 and 30 minutes to demonstrate its effect on the stomatognathic system. Forty-two healthy dentate individuals (aged 21 to 40 years) with normal occlusion and without parafunctional habits or temporomandibular dysfunction (RDC/TMD) were evaluated on the basis of the electromyographic activity of the masseter and temporal muscles before placement of a neuromuscular re-programming device, the Lucia jig, on the upper central incisors. There were no statistically significant differences (p < 0.05) in the electromyographic activity of the masticatory muscles in the different time periods. The Lucia jig changed the electromyographic activity by promoting a neuromuscular reprogramming. In most of the time periods, it decreased the activation of the masticatory muscles, showing that this device has wide applicability in dentistry. The use of a Lucia jig over 0, 5, 10, 15, 20 and 30 minutes did not promote any statistically significant increase in muscle activity despite differences in the data, thus showing that this intra-oral device can be used in dentistry.

The effect of a Lucia jig for 30 minutes on neuromuscular re-programming, in normal subjects.

The Lucia jig is a technique that promotes neuromuscular reprogramming of the masticatory system and allows the stabilization of the mandible without the interference of dental contacts, maintaining the mandible position in harmonic condition with the musculature in normal subjects or in patients with temporomandibular dysfunction (TMD). This study aimed to electromyographically analyze the activity (RMS) of the masseter and temporal muscles in normal subjects (control group) during the use of an anterior programming device, the Lucia jig, in place for 0, 5, 10, 20 and 30 minutes to demonstrate its effect on the stomatognathic system. Forty-two healthy dentate individuals (aged 21 to 40 years) with normal occlusion and without parafunctional habits or temporomandibular dysfunction (RDC/TMD) were evaluated on the basis of the electromyographic activity of the masseter and temporal muscles before placement of a neuromuscular re-programming device, the Lucia jig, on the upper central incisors. There were no statistically significant differences (p < 0.05) in the electromyographic activity of the masticatory muscles in the different time periods. The Lucia jig changed the electromyographic activity by promoting a neuromuscular reprogramming. In most of the time periods, it decreased the activation of the masticatory muscles, showing that this device has wide applicability in dentistry. The use of a Lucia jig over 0, 5, 10, 15, 20 and 30 minutes did not promote any statistically significant increase in muscle activity despite differences in the data, thus showing that this intra-oral device can be used in dentistry.

Fluorescência na odontologia restauradora: laser de diodo / Fluorescence in restorative dentistry: diode laser

Nas últimas décadas, um declínio na prevalência da doença cárie tem sido constatado nos países industrailizados, no entanto, ainda representa umas das doenças que mais acomete os seres humanos, sendo considerada um problema de saúde pública. Uma nova visão da Odontologia, denominada Intervenção Mínima, tem determinado novas tendências no sentido de abranger procedimetos mais biológicos, preventivos e menos invasivos, visando a preservação de tecidos dentais. Essa filosofia é dependente de um diagnóstico precoce. Assim, como o diagnóstico difedigno do processo de cárie por inspeção visual é limitado, existe a necessidade de detectar a doença no seu estágio mais inicial, a fim de apoiar as decisões de tratamento. Dessa forma, nos últimos anos têm surgido métodos auxiliares de diagnóstico da doença e consequente aumento do interesse por analisar a eficácia desses métodos, uma vez técnicas baseadas apenas no exame visual e radiográfico não são tão eficazes em detectar níveis iniciais de perdas minerais do esmalte dental. O laser diodo para diagnóstico de cárie foi introduzido há alguns anos. Esses sistemas baseados na autofluorescência dos tecidos dentais parecem oferecer maior eficácia na realização de diagnóstico confiável e preciso das primeiras fases da desmineralização do esmalte dental. Para tanto, esta revisão avalia criticamente o diagnóstico de cárie por fluorescência a laser.

In recent decades, a decline in the prevalence of caries has been observed in industrialized countries, yet it represents one of the most common diseases in man and is considered a public health problem. A new approach or the treatment of dental caries is advocated by Mininmal Intervention Dentistry. It emphasizes a more biological preventive and less invasive procedures, in order to preserve more dental tissue. This philosophy dependents on early diagnosis. Since a reliable diagnosis of dental caries by visual inspection and radiographic examination is limited there is a need to detect the disease in its earlist stage, to suport treatment decisions. The diode laser for caries diagnosis was introduced some years ago. These systems are based on self-fluorescence of the tissues and appear to offer greater efficacy in achieving a reliable and occurate diagnosis of earlu stages of enamel demineralization. Thus, this rewiew critically evaluares caries diagnosis using laser flueorescence.

Age and gender influence on maximal bite force and masticatory muscles thickness.

The present study aimed investigate the age and gender influence on maximal molar bite force and at outlining the criteria for normal masticatory muscle development in a sample of 177 Brazilian Caucasian dentate individuals aged 7-80 years divided into five age groups: I (7-12 years), II (13-20 years), III (21-40 years), IV (41-60 years), and V (61-80 years). Except for Group V, which comprised nine women and eight men, all groups were equally divided in respect to gender (20 M/20 F). Bite force was recorded with a mouth-adapted 1000N dynamometer and the highest out of three records was regarded as the maximal bite force. The data were submitted to multivariate statistical analysis (SPSS 17.0 p<0.05). Effects of group and gender were found, but no interactions between them. The ANOVA showed significant differences between groups bilaterally. Bonferroni's test showed that group I had significantly lower bite force means at both sides as compared to all groups, except group V. No differences were found between the left and right sides. In all the groups, gender was found to be a significant factor associated with maximal bite force. A global comparison including all the subjects and measures showed that the means of men were approximately 30% higher than those of women. Within-group comparisons yielded similar results in all groups. Muscle thickness was measured with a SonoSite Titan ultrasound tool using a high-resolution real-time 56mm/10MHz linear-array transducer. Three ultrasound images were obtained from the bilateral masseter and temporal muscles at rest and at maximal voluntary contraction. The means of the three measures in each clinical condition were analyzed with multivariate statistical analysis (SPSS 17.0 p<0.05). A gradual increase in thickness of the masseter and temporal muscles was found both at rest and maximal voluntary contraction for groups I to IV, whereas a decrease in muscle thickness was observed in group V. Multivariate analysis showed that in both conditions there was an effect of group and gender. The study of the development of the stomatognathic system in relation to age and gender can provide useful data for the identification of normal and impaired functioning patterns. The results of this study indicate that age and gender are associated with structural and functional alterations in the muscles of the stomatognathic system.