Abstract This study evaluated the stress behavior around short implants in edentulous atrophic mandibles. Six groups included implants with two diameters regular and wide (4 and 5 mm) and three lengths (5, 7 and 9 mm) as follows: Ci9 (9 x 4 mm), Ci7 (7 x 4 mm), Ci5 (5 x 4 mm), Wi9 (9 x 5 mm), Wi7 (7 x 5 mm) and Wi5 (5 x 5 mm). These groups were compared to the control group CG (11 x 4 mm). The analysis was performed with the photoelastic method (n = 6). Each model comprised 4 implants with the same length and diameter connected by a chromium-cobalt bar that simulates a fixed denture. A 0.15 kg force was applied at the end of the cantilever (15 mm), and the maximum shear stress was recorded around the distal and subsequent implants. The stress values were determined, and the quantitative data (Fringes®) were submitted to statistical analysis with one-way ANOVA and the Dunnett test (p < 0.05). It was observed that the reduction in implant length increased stress values with a significant difference (p < 0.05) between CG Ci7 and Ci5, while the increase in implant diameter reduced the stress values without any differences found between short and long implants. Implants with 5 and 7 mm with regular diameter increased stress levels while short implants with larger diameters experienced similar stress to that of longer implants.

The aim of this research was to evaluate the load distribution in tilted distal implants used in the all-on-four system. Two implant schemes were used. In both, two vertical anterior implants and tilted posterior implants were installed, one group with an angulation of 15 and another with an angulation of 35. The implants were installed together with a bar binding them all in a photoelastic model obtained from a replica of an edentulous maxilla. In this model, loads were produced in the sector of the bar cantilever, the abutment of the tilted implants and over the four implants using devices specially designed for this purpose. The bands were recorded with a digital camera, and the qualitative and quantitative analyses were carried out by means of student's t-test and the Mann-Whitney test in Biostat v. 5.0, considering a level of p<0.05 to establish a statistically significant relation. In the qualitative analysis, the implant with 35 presented the greatest amount of stress on the cantilever forces at cervical level. The quantitative studies showed fewer differences in all aspects assessed, although significant differences were observed between the two systems when loads were applied at cantilever level. It can be concluded that there are minimal differences in the stress distribution when comparing implants with angulations of 15 or 35. However, there is a greater concentration of stress at the cervical level in implants tilted to 35.

El objetivo de esta investigación fue evaluar la distribución de cargas en implantes angulados distales utilizados en el sistema "All-On-Four". Dos esquemas de implantes fueron empleados. En ambos, dos implantes verticales en el área anterior y dos implantes angulados en el sector posterior fueron instalados, utilizando angulaciones de 15 y 35 o en estos últimos. Los implantes fueron instalados de forma conjunta mediante una barra unida al sistema de resina fotoelástica obtenida de una replica de una maxila edéntula. En este modelo, las cargas fueron producidas en el sector del cantiléver de la barra, el pilar del implante angulado y, mediante un sistema genérico, sobre la totalidad de los implantes. Las bandas de estrés fueron reconocidas en una cámara digital donde los análisis cualitativos y cuantitativos fueron realizados utilizando las pruebas t de Student y Mann-Whitney en el programa computacional Biostat v. 5.0, considerando un valor de p<0,05 para establecer diferencias significativas. En el análisis cualitativo, los implantes con 35 presentaron una gran cantidad de estrés en el área de cantiléver, principalmente a nivel cervical. Los estudios cuantitativos mostraron limitadas diferencias en todos los aspectos, aunque diferencias significativas fueron alcanzadas cuando se compararon ambos sistemas después de la carga a nivel del cantiléver. Se puede concluir que hay diferencias menores en la distribución de estrés cuando se comparan implantes dentales con angulación de 15 y 35. Sin embargo, existe una mayor cantidad de concentraciones de estrés a nivel cervical en los implantes con 35 de angulación.

A síndrome da fibromialgia (SFM) é uma síndrome dolorosa crônica. A coexistência de uma condição dolorosa causada pela disfunção temporomandibular (DTM) e pela SFM tem sido frequentemente descrita por vários estudos. No entanto, a hipótese mais provável é que um conjunto de características da SFM pode levar ao aparecimento de sintomas de DTM e elas não são apenas condições coexistentes. Por isso, o objetivo deste estudo é apresentar uma revisão da literatura sobre a relação entre a fibromialgia e os sinais e sintomas da disfunção temporomandibular. Para este fim, fez-se uma pesquisa bibliográfica que envolveu o período de 1990 a 2013 nas bases de dados Medline, Pubmed, Lilacs e Scielo. Foram usadas as palavras-chave fibromialgia, disfunção temporomandibular e dor facial. Neste trabalho, apresenta-se um conjunto de achados da literatura que mostram que a fibromialgia pode levar a sintomas de DTM. Estes estudos mostraram um maior envolvimento do sistema estomatognático na SFM e que os distúrbios miogênicos do sistema mastigatório são os mais comumente encontrados nesses pacientes. A SFM parece ter uma série de características que constituem fatores predisponentes e desencadeantes para a DTM.

Fibromyalgia syndrome (FMS) is a chronic painful syndrome and the coexistence of a painful condition caused by Temporomandibular Disorders (TMD) and FMS has been frequently raised for several studies; however, a more likely hypothesis is that a set of FMS characteristics may lead to the onset of TMD symptoms and they are not merely coexisting conditions. Therefore, our aim is presenting a review of literature about the relation between fibromyalgia and the signs and symptoms of temporomandibular disorders. For this purpose, a bibliographic search was performed for the period of 1990–2013, in the Medline, Pubmed, Lilacs and Scielo databases, using the keywords fibromyalgia, temporomandibular disorders and facial pain. Here we present a set of findings in the literature showing that fibromyalgia can lead to TMD symptoms. These studies demonstrated greater involvement of the stomatognathic system in FMS and myogenic disorders of masticatory system are most commonly found in those patients. FMS appears to have a series of characteristics that constitute predisposing and triggering factors for TMD.

AIM: To compare temporomandibular (TMD) subgroups classified according to the presence of localized pain (LP) or widespread pain (WP) in order to assess the quality of life domains and verify which components affect most the functional capacity of facial pain patients. METHODS: A cross-sectional study was conducted and the Short Form-36 Health Survey was applied in order to assess quality of life. Thirty-nine TMD/WP patients, 37 TMD/LP patients and 40 subjects free of TMD complaints were evaluated. RESULTS: TMD/WP patients differed significantly from healthy controls in all SF-36 components and TMD/LP patients ranked between them. It was also observed that patients with bodily pain and TMD with WP are respectively, 4.16 and 49.42 times more likely to have low functional capacity. CONCLUSIONS: Functional capacity in TMD subgroups was only affected by the presence of bodily pain and WP. These patients feature high chance of low functional capacity. Furthermore, TMD patients with localized and widespread pain share role-emotional impairments.

This study's aims was to evaluate the stress distribution in a mandibular implant-supported prosthesis and peri-implant bone considering implant quantity, diameter and position using linear 3-D finite element analysis. Models of an anterior jaw comprised 4 groups according to implant quantity, diameter, and position: control group C, 5 regular implants; R, 3 regular implants; W, 3 wide implants; and DTR, 3 regular implants with the distal ones tilted 30º distally. The cantilever was loaded with an axial load of 50 N. Data was evaluated using von Mises stress on implants and maximum principal stress and microstrain on the bone. The W group showed the lowest value of maximum principal stress in peri-implant bone of the loaded side (4.64 MPa) when compared to C (5.27 MPa), DTR (5.94 MPa), and R (11.12 MPa). Lower stress values in the loaded implants were observed in the experimental groups when compared to the C group. However, the unloaded implants presented opposite results. All the screws of the W group presented lower stress values when compared to the C group. However, the R and DTR groups presented an increase in stress values with the exception of the loaded screw. A reduction in the number of implants associated with wider implants reduced the stress in the bone and prosthetic components.

Conventional tilted implants are used in oral rehabilitation for heavily absorbed maxilla to avoid bone grafts; however, few research studies evaluate the biomechanical behavior when different angulations of the implants are used. The aim of this study was evaluate, trough photoelastic method, two different angulations and length of the cantilever in fixed implant-supported maxillary complete dentures. Two groups were evaluated: G15 (distal tilted implants 15°) and G35 (distal tilted implants 35°) n = 6. For each model, 2 distal tilted implants (3.5 x 15 mm long cylindrical cone) and 2 parallel tilted implants in the anterior region (3.5 x 10 mm) were installed. Photoelastic models were submitted to three vertical load tests: in the end of cantilever, in the last pillar and in the all pillars at the same time. We obtained the shear stress by Fringes software and found values for total, cervical and apical stress. The quantitative analysis was performed using the Student tests and Mann-Whitney test; p ≥ 0.05. There is no difference between G15 and G35 for total stress regardless of load type. Analyzing the apical region, G35 reduced strain values considering the distal loads (in the cantilever p = 0.03 and in the last pillar p = 0.02), without increasing the stress level in the cervical region. Considering the load in all pillars, G35 showed higher stress concentration in the cervical region (p = 0.04). For distal loads, G15 showed increase of tension in the apical region, while for load in all pillars, G35 inclination increases stress values in the cervical region.

O objetivo deste trabalho foi avaliar o comportamento de acadêmicos de Odontologia com relação ao controle da infecção cruzada, verificando se alunos que estão mais adiantados no curso de formação profissional apresentam melhores condutas de biossegurança. Os temas abordados contemplaram: etapas dos processos de esterilização (desinfecção pré-lavagem, lavagem e esterilização); desinfecção de superfícies e utilização de barreira mecânica. Para isto foram sorteados 117 alunos matriculados nas clínicas da faculdade, convidados a responder um questionário com 19 perguntas objetivas. As respostas foram submetidas à análise descritiva e ao teste do χ². Foi verificado que 94,0% dos alunos não realizam desinfecção pré-lavagem, 86,2% sempre fazem a lavagem dos instrumentais antes da esterilização e 2,5% utilizam proteção das mãos adequada para este fim. A desinfecção das superfícies é realizada por 52% dos alunos e a barreira mecânica é habitualmente utilizada por 73% deles. A análise estatística identificou que alunos do oitavo e nono períodos apresentam melhor comportamento na conduta de organização do instrumental para esterilização e desinfecção de superfícies. E constatou-se que alunos dos períodos mais avançados apresentam melhores condutas. Não há uma padronização no comportamento a respeito da prevenção da infecção cruzada no que diz respeito às etapas básicas de biossegurança no centro acadêmico avaliado.

The aim of this study was to evaluate the behavior of dental students regarding cross infection control, verify that students who are more advanced in the course had better biosecurity conduct. The topics covered included: stages of sterilization processes (disinfection pre-washing, washing and sterilization), surface disinfection and use of mechanical barrier. For this 117 students enrolled in clinical discipline were randomly selected and invited to answer a questionnaire with 19 objective questions. The responses were analyzed descriptively and the χ² test. It was found that 94.0% of students do not perform disinfection prewash, 86.2% always do the washing of instruments prior to sterilization and 2.5% use hand protection appropriate for this purpose. Disinfection of surfaces is performed by 52% of the students and the mechanical barrier is commonly used by 73% of them. Statistical analysis identified that students in eighth and ninth periods have better behavior in to organization of the instrumental for sterilization and to disinfection of surfaces. It was found that students in the later periods show better behavior. There is no a pattern in behavior regarding the prevention of cross infection to the basic steps of biosafety academic center evaluated.