Marcele Jardim Pimentel

Features of Temporomandibular Disorders in Fibromyalgia Syndrome

Abstract This study aimed to investigate the prevalence of clinical features of temporomandibular disorders (TMD) in patients with fibromyalgia. The test group (FMG) consisted of 40 women with fibromyalgia (FM) compared to the control group of 40 healthy subjects using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The variables were compared using Fisher’s exact test and a Mann-Whitney test. Facial pain was reported by 85% of the FM group, and 77.5% were diagnosed with myofascial TMD. Muscle pain during jaw movements, daytime bruxism/clenching, and limited mouth opening were significantly higher in the test group. There was no difference between groups in: 1. joint noises; 2. sleep bruxism/clenching; and 3. excursive or non-excursive movements. Classic signs of TMD, such as joint noise and self-reporting of clenching at night, are not associated with fibromyalgia syndrome as demonstrated in the current study. However, the self-reported daytime parafunctions, muscle pain in jaw movements, and limited mouth opening are features of the patients in the current study. This study revealed specific muscle involvement of TMD is also presence in FM.

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

This studys 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.

Biofilm and saliva affect the biomechanical behavior of dental implants

Friction coefficient (FC) was quantified between titanium-titanium (Ti-Ti) and titanium-zirconia (Ti-Zr), materials commonly used as abutment and implants, in the presence of a multispecies biofilm (Bf) or salivary pellicle (Pel). Furthermore, FC was used as a parameter to evaluate the biomechanical behavior of a single implant-supported restoration. Interface between Ti-Ti and Ti-Zr without Pel or Bf was used as control (Ctrl). FC was recorded using tribometer and analyzed by two-way Anova and Tukey test (p<0.05). Data were transposed to a finite element model of a dental implant-supported restoration. Models were obtained varying abutment material (Ti and Zr) and FCs recorded (Bf, Pel, and Ctrl). Maximum and shear stress were calculated for bone and equivalent von Misses for prosthetic components. Data were analyzed using two-way ANOVA (p<0.05) and percentage of contribution for each condition (material and FC) was calculated. FC significant differences were observed between Ti-Ti and Ti-Zr for Ctrl and Bf groups, with lower values for Ti-Zr (p<0.05). Within each material group, Ti-Ti differed between all treatments (p<0.05) and for Ti-Zr, only Pel showed higher values compared with Ctrl and Bf (p<0.05). FC contributed to 89.83% (p<0.05) of the stress in the screw, decreasing the stress when the FC was lower. FC resulted in an increase of 59.78% of maximum stress in cortical bone (p=0.05). It can be concluded that the shift of the FC due to the presence of Pel or Bf is able to jeopardize the biomechanical behavior of a single implant-supported restoration.

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.

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 Tukeys 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.

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.

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.

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.

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.

Biossegurança: comportamento dos alunos de Odontologia em relação ao controle de infecção cruzada

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.