Short implants to support mandibular complete dentures - photoelastic analysis.

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.

Short implants to support mandibular complete dentures - photoelastic analysis

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.

Relação de distúrbios temporomandibulares e alterações do padrão de sono na síndrome da fibromialgia ­ revisão da literatura / Relationship of temporomandibular disorders and sleep patterns in fibromyalgia syndrome

A fibromialgia é uma síndrome reumática caracterizada por quadros dolorosos intensos. A presença da dor muitas vezes chega a causar incapacidade e indisposição, mesmo para realização de atividades rotineiras, bem como parece afetar o sono em grande parte dos pacientes. Acredita-se que a perpetuação de alterações no padrão de sono crie uma situação cíclica que intensifica os quadros dolorosos e a fadiga. Os distúrbios temporomandibulares (DTM) que são caracterizados por quadros de dor também vêm sendo relacionados com alterações no sono. Essas duas condições, apesar de distintas, parecem coexistir em um grande número de portadores de fibromialgia, levando-se a pesquisas que visam buscar a influência dessa relação como causa e efeito dentro deste grupo de pacientes. Neste contexto, este trabalho teve o objetivo de recolher informações dentro da literatura sobre essas duas condições, sua influência nas alterações do sono, bem como reunir estudos que busquem esclarecer a relação existente entre as duas condições. Para isto foram reunidos trabalhos publicados na base de dados PubMed, LILACSeMEDLINEutilizando-se os termos fibromialgia, DTM e sono, nos idiomas inglês e português. Os trabalhos apontam que há uma prevalência alta entre mulheres e que os portadores de fibromialgia apresentam alterações específicas no padrão de sono, bem como há uma importante correlação desta condição com os distúrbios temporomandibulares (AU).

Fibromyalgia syndrome is characterized by severe painful conditions. The presence of pain can result in some disability and even unwillingness to perform routine activities, and seems to affect sleep in most patients. It is believed that the changes in sleep pattern creates a cyclic condition and can increase fatigue painful conditions. The temporomandibular disorder (TMD) is characterized by pain frameworks have also been related to changes in sleep. These two conditions, while distinct, seem to coexist in a large number of patients with fibromyalgia, leading several researchs concerning the influence of this relationship within this group of patients. Therefore, this work aimed to collect information in the literature on these two conditions, its influence on sleep disorders as well as gathering studies that seek to clarify the relationship between these two conditions. For this were selected studies published in PubMed, LILACS, and MEDLINE using the terms fibromyalgia, TMD and sleep, in English and Portuguese. The studies indicate that there is a high prevalence among women and that patients with fibromyalgia have specific changes in sleep patterns, and there is a significant correlation of this condition with temporomandibular disorders (AU).

Stress analysis in maxillary all-on-four model / Análisis del estrés en un modelo maxilar del concepto all-on-four

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.

Sleep quality and facial pain in fibromyalgia syndrome.

AIMS: This study aims to evaluate the sleep conditions in fibromyalgia syndrome and the influence of the temporomandibular disorders (TMDs) and fibromyalgia association in self-reported sleep quality. METHODOLOGY: Forty female patients with fibromyalgia (FMS) were compared with 40 healthy women [control group (CG)]. Three questionnaires were used (i.e. RDC/TMD to diagnose TMD and to determine pain intensity and disability and Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) to assess sleep conditions). Statistical analyses were performed using the Wilcoxon-Mann-Whitney test to ordinal variables, Student's t-test to obtain the quantitative total scores of PSQI and chronic pain classification, Spearman's rho to determine the correlation between facial pain and quality sleep, and Fisher's exact test for other variables. RESULTS: A moderate correlation between facial pain intensity and low sleep quality was found (rho = 0·56; P<0·0001); however, TMD and FMS association did not show worse sleep quality (P>0·05). Excessive daytime sleepiness was more prevalent in FMS (37·5%; P<0·0001) besides having the worst sleep quality (PSQI = 12·72) compared with CG (PSQI = 4·62). CONCLUSION: Fibromyalgia patients experience intense facial pain in addition to poor sleep and high disabilities. TMD and FMS association do not appear to worsen this condition; however, facial pain intensity was correlated with low sleep quality.

Temporomandibular disorders in fibromyalgia syndrome: a short-communication.

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, 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 of 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 the most commonly found in those patients. FMS appears to have a series of characteristics that constitute predisposing and triggering factors for TMD.

Photoelastic analysis of fixed partial prosthesis crown height and implant length on distribution of stress in two dental implant systems.

The aim of this study was to evaluate by photoelastic analysis stress distribution on short and long implants of two dental implant systems with 2-unit implant-supported fixed partial prostheses of 8 mm and 13 mm heights. Sixteen photoelastic models were divided into 4 groups: I: long implant (5 × 11 mm) (Neodent), II: long implant (5 × 11 mm) (Bicon), III: short implant (5 × 6 mm) (Neodent), and IV: short implants (5 × 6 mm) (Bicon). The models were positioned in a circular polariscope associated with a cell load and static axial (0.5 Kgf) and nonaxial load (15°, 0.5 Kgf) were applied to each group for both prosthetic crown heights. Three-way ANOVA was used to compare the factors implant length, crown height, and implant system (α = 0.05). The results showed that implant length was a statistically significant factor for both axial and nonaxial loading. The 13 mm prosthetic crown did not result in statistically significant differences in stress distribution between the implant systems and implant lengths studied, regardless of load type (P > 0.05). It can be concluded that short implants showed higher stress levels than long implants. Implant system and length was not relevant factors when prosthetic crown height were increased.

Photoelastic analysis of all-on-four concept using different implants angulations for maxilla.

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.

Mastication movements and sleep quality of patients with myofascial pain: occlusal device therapy improvements.

STATEMENT OF PROBLEM: Patients with myofascial pain experience impaired mastication, which might also interfere with their sleep quality. PURPOSE: The purpose of this study was to evaluate the jaw motion and sleep quality of patients with myofascial pain and the impact of a stabilization device therapy on both parameters. MATERIAL AND METHODS: Fifty women diagnosed with myofascial pain by the Research Diagnostic Criteria were enrolled. Pain levels (visual analog scale), jaw movements (kinesiography), and sleep quality (Epworth Sleepiness Scale; Pittsburgh Sleep Quality Index) were evaluated before (control) and after stabilization device use. Range of motion (maximum opening, right and left excursions, and protrusion) and masticatory movements during Optosil mastication (opening, closing, and total cycle time; opening and closing angles; and maximum velocity) also were evaluated. Repeated-measures analysis of variance in a generalized linear mixed models procedure was used for statistical analysis (α=.05). RESULTS: At baseline, participants with myofascial pain showed a reduced range of jaw motion and poorer sleep quality. Treatment with a stabilization device reduced pain (P<.001) and increased both mouth opening (P<.001) and anteroposterior movement (P=.01). Also, after treatment, the maximum opening (P<.001) and closing (P=.04) velocities during mastication increased, and improvements in sleep scores for the Pittsburgh Sleep Quality Index (P<.001) and Epworth Sleepiness Scale (P=.04) were found. CONCLUSION: Myofascial pain impairs jaw motion and quality of sleep; the reduction of pain after the use of a stabilization device improves the range of motion and sleep parameters.

Quality of life in temporomandibular disorder patients with localized and widespread pain

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...

Stress analysis of different configurations of 3 implants to support a fixed prosthesis in an edentulous jaw.

This study's aim 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 30° 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.

Evaluation of radioprotective effect of pilocarpine ingestion on salivary glands.

There is controversy concerning the effect of pilocarpine in the reversal of radio-induced xerostomia; however, the tests are usually performed at the end of radiotherapy. The present study evaluated the radioprotective effects of pilocarpine when ingested during radiation treatment. Eleven patients (recently diagnosed with head and neck cancer who were not undergoing radiotherapy) were divided into two groups: the control group (saline solution intake n=6) and the pilocarpine-treated (5 mg pilocarpine three times daily, n=5) group, in a prospective and double-blinded study. For five weeks, oral conditions, unstimulated salivary flow and stimulated saliva flow were collected weekly, with the first collection occurring prior to radiation therapy. As early as the second week, the control group exhibited oral complications and greater reduction in salivary flow rate. At the end of the study, the pilocarpine-treated group presented mean values of salivary flow greater than those of the control group. Pilocarpine intake applied simultaneously with radiotherapy demonstrated encouraging results with regard to lowering salivary flow reduction and incidence of xerostomia, as well as of oral complications.

Prosthetic improvement of pronounced buccally positioned zygomatic implants: a clinical report.

This report presents a prosthetic technique for the improvement of surgically positioned, buccally placed zygomatic implants with the use of custom abutments for improved retention screw position and an esthetic implant reconstruction. The patient presented four zygomatic implants with pronounced buccal inclination. The anterior implants were inclined toward the location where the anterior artificial teeth should be placed during rehabilitation. As the manufacturer does not provide angulated abutments, we attempted the waxing and overcasting of a prosthetic abutment, repositioning the access holes of the prosthetic screws to a more palatal position. This clinical report demonstrates that abutment customization could be an interesting way to relocate the access holes of the prosthetic screws in cases of zygomatic implants with pronounced buccal inclination.

Stress analysis of different configurations of 3 implants to support a fixed prosthesis in an edentulous jaw

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.

The Use of Implants to Improve Removable Partial Denture Function.

The oral rehabilitation with conventional removable partial dentures in Kennedy class I patients allows continuous bone resorption, dislodgment of the prosthesis during the mastication caused by the resilience of the mucosa, and rotation of the prosthesis. Thus, the associations of distal implants become an attractive modality of treatment for these patients. This case report presented an association of removable partial dentures, milled crowns and osseointegrated implants to rehabilitate a partial edentulous patient. A removable partial denture associated with implants and metal-ceramic milled crowns can offer excellent esthetics, and will improve function and biomechanics, at a reduced cost.

Oral Appliance for the Treatment of Severe Obstructive Sleep Apnea in Edentulous Patient.

Oral appliances have attracted interest for the treatment of mild and moderate obstructive sleep apnea (OSA) and the mandibular repositioning device (MRD) or a tongue-retainer device (TRD) is usually indicated to increase the upper air space. Describes a combination of MRD (with 60 % maximum mandibular protrusion) and TRD to treat severe OSA. Polysomnography (PSG) and two questionnaires: the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) evaluated the sleep pattern in two times (after and before the use of oral appliance). The initial PSG exam was compatible with diagnoses severe OSA and the Apnea-Hypopnea Index was 40.4, and 54 % oxygen saturation -spO(2). The ESS and PSQI scores were 11 and 6, respectively. After she began wearing the device she stopped snoring, her Apnea-Hypopnea Index decreased to 17.6, presented a sleep efficiency of 81.6 % and had a 77 % spO(2). The ESS and PSQI scores dropped to three. MRD in association with the tongue-retainer was effective in reducing the severity of the apnea for this edentulous patient.

Desmistificando a evolução dos sistemas cerâmicos / Demystifying the evolution of ceramic systems

Os sistemas cerâmicos apresentam uma incrível evolução na busca implacável pela estética. A união desses sistemas aos metais foi necessária em um primeiro momento para compensar a friabilidade intensa que esses sistemas apresentavam inicialmente. Todo o processo de evolução desse grupo de materiais gira em torno de abrir mão do metal, retirando-os dos processos de reabilitação. O grande impasse é alcançar com as cerâmicas a resistência que o metal proporciona e por isso as pesquisas se concentram em reforçar os sistemas cerâmicos tornando-os capazes de resistir às forças e tensões geradas durante a função mastigatória. O objetivo deste trabalho é relatar esse processo de evolução tornando o entendimento sobre esse tema mais fácil, assim como esclarecer, dentro de uma classificação simplificada, a indicação, o potencial de resistência e grau de translucidez dentre os diversos sistemas. Através do levantamento bibliográfico, pode-se afirmar que atualmente é totalmente possível a realização de restaurações unitárias em qualquer posição no arco dentário. Já para reabilitações com próteses extensas, principalmente na região de molares, essa escolha deve ser bastante criteriosa. Dispomos de sistemas cerâmicos para confecção de copings altamente capazes de resistir à carga, mas estudos clínicos randomizados de longo prazo ainda são necessários para avaliar a vida útil desse tratamento.

Ceramic systems represent an incredible evolution in the search for aesthetics. In a first moment the association of these systems with metals was necessary to compensate its low resistance. The evolution of this group of materials is moving toward giving up the metal material, removing them from the oral rehabilitation. The major objective is to obtain a ceramic with the same resistance provided by the metal and therefore most researches are focused on strengthening the ceramic systems so that they can resist to the pressure generated during masticatory function. The aim of this work is to describe this process of evolution as well as clarify, within a simplified classification, the indication, the resistance and translucency of ceramic systems. Through literature review we can affirm that the realization of single crowns is possible in any position in the dental arch. For extensive rehabilitation with prostheses, especially in the molars region, this choice should be carefully evaluated. Currently, more resistant systems are used to ceramic copings highly capable of load resistance, but randomized clinical trials of long-term are still needed to evaluable the lifetime of the material.

Manejo e adequação de prótese provisória sobre implantes / Management and adjustment of implantsupported provisional prosthesis

Introdução: As próteses provisórias sobre implante seguem os preceitos das próteses convencionais, tendo como princípio básico para o sucesso o respeito aos tecidos de suporte. Portanto, é necessário um acompanhamento das respostas destes tecidos após a instalação da peça protética. Objetivo: Este relato descreve um protocolo de acompanhamento e ajustes de uma prótese provisória fixa sobre implantes correlacionando a anatomia final da prótese à capacidade de higienização alcançada pelo paciente durante esse período. Conclusão: Na fase provisória assistida foi possível detectar a necessidade de redução do contorno lingual e adequação da margem cervical para facilitar o acesso à higienização e restaurar a saúde periodontal

Influence of post-thickness and material on the fracture strength of teeth with reduced coronal structure.

PURPOSE: To evaluate the fracture strength of endodontically treated teeth with reduced coronal structure reinforced with glass-fiber posts and cast posts and core (nickel-chromium alloy) with different thickness. MATERIALS AND METHODS: Forty maxillary central incisors were sectioned at 1 mm of the cementoenamel junction and endodontically treated. The teeth were divided into four groups (n = 10) and restored with cast post and core and glass-fiber posts with diameters of 1.5 mm and 1.1 mm. The fracture strength was evaluated using a Universal Testing Machine (Instron 1144) at 45° of angulation. The results were submitted to analysis of variance two-way and Tukey's test (P < 0.05). The failure mode was also evaluated. RESULTS: Cast post and core were statistically superior to the glass-fiber posts with the self-post diameter (P = 0.001). When the self-post material was considered, no significant difference was observed between the two post-diameters (P = 0.749). The glass-fiber post-groups presented more fractures in the cervical third than the cast post and core groups. CONCLUSION: Teeth restored with cast post and cores present higher fracture strength than those reinforced with glass-fiber posts. An increased post-thickness does not increase the fracture strength. Glass-fiber posts lead to less severe fractures.

Facial pain associated with fibromyalgia can be marked by abnormal neuromuscular control: a cross-sectional study.

BACKGROUND: Temporomandibular disorder (TMD) development in fibromyalgia syndrome (FMS) is not yet fully understood, but altered neuromuscular control in FMS may play a role in triggering TMD. OBJECTIVE: The purpose of this study was to verify the association between neuromuscular control and chronic facial pain in groups of patients with FMS and TMD. DESIGN: A cross-sectional study was conducted. METHODS: This study involved an analysis of facial pain and electromyographic activity of the masticatory muscles in patients with FMS (n=27) and TMD (n=28). All participants were evaluated according to Research Diagnostic Criteria for Temporomandibular Disorders and surface electromyography (SEMG). Myoelectric signal calculations were performed using the root mean square and median frequency of signals. RESULTS: The data revealed premature interruption of masticatory muscle contraction in both patient groups, but a significant correlation also was found between higher median frequency values and increased facial pain. This correlation probably was related to FMS because it was not found in patients with TMD only. Facial pain and increased SEMG activity during mandibular rest also were positively correlated. LIMITATIONS: Temporal conclusions cannot be drawn from the study. Also, the study lacked a comparison group of patients with FMS without TMD as well as a control group of individuals who were healthy. CONCLUSIONS: Altered neuromuscular control in masticatory muscles may be correlated with perceived facial pain in patients with FMS.