Relationship between self-reported pain, pain threshold, pain catastrophization and quality of life in patients with TMD.

Background: The aim of this study was to verify if there is a relationship between self-reported pain, PPT (pressure pain threshold) of the masseter, temporal and sternocleidomastoid muscles, pain catastrophizing and quality of life in patients with TMD (temporomandibular disorder) of muscular origin. Material and Methods: Ninety-seven patients with muscular TMD (TMD group) and 97 asymptomatic (control group) were included in the study. The evaluation methods used were: 1) Self-reported pain was assessed using the Visual Analogue Scale (VAS) for questions 7, 8 and 9 of the RDC/TMD Axis I questionnaire; 2) The PPT assessment was performed using a digital algometer on the masseter, temporal, and sternocleidomastoid muscles (both sides); 3) Pain catastrophizing was assessed using the PCS (Pain Catastrophizing Scale); and 4) Oral health-related quality of life was assessed using the OHIP-14 (Oral Healthy Impact Profile-14). Data were submitted to Spearman correlation and logistic regression (p<0.05). Results: There were significant positive correlations between self-reported pain (VAS-Q7, VAS-Q8 and VAS-Q9), pain catastrophizing (PCS-Helplessness, PCS-Magnification, PCS-Rumination and PCS-Total) and quality of life (OHIP-14) (p<0.05). There was a significant negative correlation of self-reported pain (VAS-Q8) with PPT of the temporal (left) and sternocleidomastoid (both sides) (p<0.05). The rumination and magnification domains increased the chance of high self-reported pain in all situations (VAS-Q7, VAS-Q8 and VAS-Q9) (p<0.05). The helplessness domain only increased the chance of high self-reported pain for VAS-Q8 (p<0.05). The presence of TMD of muscular origin, high self-reported pain (VAS-Q7) or pain catastrophizing increased the chance of a low quality of life in relation to the control group (p<0.05). In addition, the reduction in sternocleidomastoid PPT increased the chance of poor quality of life (p<0.05). Key words:Myofascial pain syndromes, pain catastrophizing, myalgia, quality of life, surveys and questionnaires, temporomandibular joint disorders.

Clinical reproducibility of different centric relation recording techniques in edentulous individuals: An observational cross-sectional study.

PURPOSE: To assess the reproducibility of four different centric relation (CR) recording techniques, and time spent performing each technique in edentulous individuals. MATERIALS AND METHODS: Four techniques were assessed: extraoral gothic arch (EOGA) tracing, intraoral gothic arch (IOGA) tracing, deglutition (D), and frontal manipulation with tongue elevation (FMTE). Twelve subjects participated in the study; four technique records were performed on each volunteer by the same operator. Each record was repeated three times, in the same period of the day, with a 30 min interval between each technique. The reproducibility of each technique was assessed by the tri-dimensional displacement of the position of the condylar housing (mandible condyle) to the wall of the condylar guide (glenoid cavity) in the semi-adjustable articulator (anteroposterior, mediolateral, and superior-inferior). The time spent on each technique was timed in seconds (from the beginning of each technique until the wax occlusion fixation). The analysis of variance (ANOVA) and the Tukey test were performed for anteroposterior displacement (two-way) and for time spent on CT recording techniques (one-way) (α < 0.05). Regarding mediolateral and superior-inferior displacements, the nonparametric Kruskal-Wallis was performed for the comparison between recording methods, whereas the Mann-Whitney test was performed for the comparison between sides (α < 0.05). RESULTS: The factor recording technique interfered with the anteroposterior displacement (ANOVA: α < 0.001; F = 11.396). The technique D (right side: 3.78 ± 0.69 mm; left side: 3.45 ± 0.74 mm) showed a statistically significant difference compared to the other techniques (EOGA: right side: 3.00 ± 0.00 mm; left side: 3.00 ± 0.00 mm; FMTE: right side: 2.81 ± 0.52 mm; left side: 2.82 ± 0.79 mm; IOGA: right side: 2.90 ± 0.65 mm; left side: 3.12 ± 0.44 mm). The time spent on the recording technique influenced the results (ANOVA: α < 0.001; F = 21.118). The IOGA (340.40 ± 163.41 s) and EOGA (285.93 ± 133.84 s) required more time compared to the D (86.00 ± 34.33 s) and FMTE (101.33 ± 36.72 s) techniques. CONCLUSION: Graphic recordings showed better reproducibility and accuracy of the position of the centric relation.

Relationship of excessive daytime sleepiness with bruxism, depression, anxiety, stress, and sex in odontology students - A cross sectional study.

Background: To verify if there is a correlation of excessive daytime sleepiness (EDS) with bruxism, depression, anxiety, stress, and sex in odontology students. Material and Methods: Four hundred dental students were selected. Students included in the study were those that were healthy, over 18 years old, and with similar weekly academic activities. Students excluded were those with temporomandibular disfunction, a high possibility of possessing obstructive sleep apnea and illnesses that cause EDS; along with smokers, users of illicit drugs, users of psychiatric medication, and those that abuse the consumption of alcohol. After the application of these criteria, 128 students were included in this study. EDS, bruxism, depression, anxiety, and stress were evaluated by the Epworth Sleepiness Scale, the Pintado et al. questionnaire, Beck Depression Inventory, Beck Anxiety Inventory, and the LIPP Adult Stress Symptom Inventory. Afterwards, the Spearman test (p< 0.05) was applied. Results: A high probability of EDS was present in 33.6% of the students. There was a positive correlation of EDS with females (Rank Correlation= 0.209; p= 0.018) and depression (Rank Correlation= 0.174; p= 0.049); between females and stress (Rank Correlation= 0.199; p= 0.024), and between females and anxiety (Rank Correlation= 0.178; p= 0.045). There was a positive correlation of bruxism with anxiety (Rank Correlation= 0.255; p= 0.004) and stress (Rank Correlation= 0.201; p= 0.023). There was no correlation of EDS with bruxism (p= 0.354), stress (p= 0.277), or anxiety (p= 0.114). There was no correlation of bruxism with females (p= 0.082) or depression (p= 0.362). Conclusions: A high probability of EDS was present in 33.6% of dentistry students, and there was a positive correlation of EDS with females and depression. Key words:Bruxism, depression, anxiety, stress, disorders of excessive somnolence, dentistry.

Effect of Rehabilitation with a New Ocular Prosthesis on Electromyography of the Occipitofrontalis, Temporal, Masseter, and Sternocleidomastoid.

OBJECTIVES: The aim of this study was to verify during facial expressions ("happy," "sad," "fearful," "angry," "surprised," and "disgusted") if: (1) there would be difference in the electromyography (EMG) of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles on the normal side (NS) compared with the affected side (AS) (without the use of an ocular prosthesis) in individuals with unilateral absence of the eyeball, and (2) the rehabilitation with a new ocular prosthesis would affect the EMG of the muscles studied on the AS in these individuals. MATERIALS AND METHODS: Thirteen individuals, without temporomandibular disorder, with good health, with unilateral absence of the eyeball (the eye must have been removed by evisceration or enucleation), and users or nonusers of an ocular prosthesis were included. EMG of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles was performed during rest and facial expressions ("happy," "sad," "fearful," "angry," "surprised," and "disgusted") before (T0) and 90 days after (T1) rehabilitation with a new ocular prosthesis. The analyses were performed in T0 on NS and AS (without the use of an ocular prosthesis), and in T1 on AS with the new ocular prosthesis. STATISTICAL ANALYSIS: All data were submitted to the Student's t-test with p < 0.05. RESULTS: There was no statistically significant difference comparing the AS with the NS in T0 for all muscles studied, during all facial expressions evaluated (p > 0.05). There was no statistically significant difference comparing the AS in T0 with itself in T1 for all muscles studied, during all facial expressions evaluated (p > 0.05). CONCLUSION: Eye loss did not affect the EMG of studied muscles when comparing NS with AS (without the use of an ocular prosthesis). The rehabilitation with ocular prosthesis was not capable of changing the EMG on AS.

Masticatory efficiency, bite force and electrical activity of the masseter and temporalis muscles in bodybuilders.

BACKGROUND: This study aimed to compare the masticatory efficiency, the maximum voluntary occlusal bite force (MVOBF) and the electrical activity (EMG) of masticatory muscles of practitioners of upper limb bodybuilding before and after physical activity. MATERIAL AND METHODS: Twenty healthy individuals (10 men and 10 women, age from 18 to 30 (mean of 24.7 years old) without masticatory system disorders, that regularly practice hypertrophic physical activity were submitted to the analyses of masticatory efficiency, MVOBF, and surface EMG of the temporalis and masseter muscles. The masticatory efficiency was analyzed by comminution of the artificial material (Optocal®) and a sieving method. The MVOBF was measured by a dynamometer, and EMG was evaluated during resting mandibular position, maximum voluntary clenching (MVC), and MVC with a Parafilm M tape between teeth, and free mastication of chewing gum. The analyses were made before (T0) and immediately after the performance of upper limb bodybuilding exercises (T1). The data of masticatory efficiency and MVOBF were submitted to the Student T-test, and their correlations were analyzed by the Pearson correlation test, and the EMG data were submitted to the 2-way repeated measures ANOVA, all tests with a 5% significance. RESULTS: There was a significant decrease of masticatory efficiency after the training. No statistical difference in the MVOBF and EMG was found, and there was a positive correlation between masticatory efficiency and MVOBF. CONCLUSIONS: Therefore, changes were found for masticatory efficiency only, which decreased after hypertrophic exercise. There was a positive correlation between masticatory efficiency and MVOBF. Key words:Masticatory efficiency, bite force, physical activity, electromyography.

Impact event and orofacial pain amid the COVID-19 pandemic in Brazil: a cross-sectional epidemiological study.

OBJECTIVES: This study aims to assess the impact of social isolation, due to the Covid-19 pandemic, on mental health, Temporomandibular Disorder (TMD) and orofacial pain in men and women. METHODOLOGY: Individuals living in Brazil answered an online questionnaire on their sociodemographic and behavioral aspects, emotional scale (DASS-21), Impact of Event Scale, and Pain Screener in Temporomandibular Disorders (TMD-Pain Screener) during June 2020. Descriptive statistical analyses and logistic and linear regressions were applied (5% significance). RESULTS: Overall, 2301 individuals were included, 89.1% practiced social isolation, 72.6% were employed/studying, at least 15% presented severe or extremely severe levels of emotional distress and presence of powerful (34.1%) and severe impact event (15%). During the outbreak, 53.2% perceived feeling worse and 31.8% reported that orofacial pain started or worsened after the pandemic outbreak. Gender was associated with "social class" (P=0.036), "pain/stiffness in the jaw on awakening" (P=0.037), "change of pain during jaw habits" (P=0.034) and "perception of change in the situations mentioned in the TMD-Pain Screener" (P=0.020), "depression" (P=0.012), "anxiety" (P=0.006) and "impact of the event" (P=8.3E-11). Social isolation had a lesser chance to change the routine, to be practiced by the unemployed/not studying, and to be practiced by men (all with P<0.001). Associations were found between social class and all subscales of the DASS-21 and IES, all with P<0.001. CONCLUSIONS: The practice of social isolation has social determinants. High levels of psychological and event impacts were detected. The presence of orofacial pain seemed to increase during the health crisis, and there were gender differences in the response to the COVID-19 pandemic.

Influence of thermocycling and disinfection on the color stability and hardness of thermoplastic sheets used for occlusal splint fabrication.

The aim of this study was to compare PETG/TPU (polyethylene terephthalate glycol/thermoplastic polyurethane) with PETG (polyethylene terephthalate glycol), based on color stability and microhardness. Sixty circular specimens (10 mm in diameter × 3 mm thick) were fabricated (30 PETG/TPU and 30 PETG). The specimens in both groups were submitted to 2000 thermal cycles in alternating baths of 60 seconds at 5°C ± 1°C and 55°C ± 1°C. The specimens were then divided into subgroups (n = 10) that were disinfected 15 minutes per day for 60 days in 1 of 3 solutions: liquid soap, 2% chlorhexidine, or Listerine. Color change (∆E*) and Knoop microhardness tests were performed at baseline (T0), after thermocycling (T1), and after disinfection (T2). Analysis of variance (ANOVA) and Tukey test were used (P < 0.05). ANOVA showed that there was no statistically significant difference in color change between the 2 materials after thermocycling (∆E*1) or after disinfection (∆E*2), regardless of the disinfectant. Intragroup comparisons (Listerine, liquid soap, and 2% chlorhexidine) of the 3 PETG/TPU groups or 3 PETG groups after disinfection revealed no statistically significant difference for microhardness. Comparison of PETG/TPU with PETG based on the overall mean microhardness showed that the PETG/TPU had a significantly greater mean surface hardness value (P < 0.05). The Tukey test revealed statistically significant increases in microhardness at T1 and T2 for PETG/TPU and PETG so that T0 < T1 < T2 (P < 0.05). Both thermoplastic materials demonstrated an increase in hardness after thermocycling and after disinfection, and both showed similar color changes regardless of the disinfection method. Based on the color evaluation, the liquid soap proved to be the best option for disinfection of PETG/TPU and PETG, because the color change (∆E* value) was clinically acceptable for both materials.

Nerve Growth Factor-Induced Sensitization of the Sternocleidomastoid Muscle and Its Effects on Trigeminal Muscle Sensitivity and Pain Profiles: A Randomized Double-Blind Controlled Study.

AIMS: To investigate whether localized sensitization of the sternocleidomastoid (SCM) muscle using nerve growth factor (NGF) would affect masseter and anterior temporalis muscle sensitivity and pain profiles. METHODS: A total of 28 healthy participants attended two sessions (T0 and T1). At T0, the maximum voluntary occlusal bite force (MVOBF), as well as pressure pain thresholds (PPT), mechanical sensitivity, and referred pain/sensations for the SCM, masseter, and temporalis muscles, were assessed. Participants also completed the Pain Catastrophizing Scale (PCS), the Pain Vigilance and Awareness Questionnaire (PVAQ), and the Neck Disability Index (NDI). After these assessments, 14 participants received an injection of NGF into the SCM, and 14 received an injection of isotonic saline solution. At T1 (48 hours postinjection), the participants were again submitted to the same evaluations. RESULTS: NGF caused significant mechanical sensitization in the SCM (P < .025), but not in the masseter or temporalis muscles (P > .208). It also caused significant increases in NDI score (P = .004). No statistically significant differences were found for MVOBF, frequency of referred pain/sensations, or questionnaire scores (P > .248). CONCLUSION: These results suggest that 48 hours after localized sensitization of the SCM, the primary response is impairment of neck function, but not jaw function.

Impact event and orofacial pain amid the COVID-19 pandemic in Brazil: a cross-sectional epidemiological study

Abstract Objectives This study aims to assess the impact of social isolation, due to the Covid-19 pandemic, on mental health, Temporomandibular Disorder (TMD) and orofacial pain in men and women. Methodology Individuals living in Brazil answered an online questionnaire on their sociodemographic and behavioral aspects, emotional scale (DASS-21), Impact of Event Scale, and Pain Screener in Temporomandibular Disorders (TMD-Pain Screener) during June 2020. Descriptive statistical analyses and logistic and linear regressions were applied (5% significance). Results Overall, 2301 individuals were included, 89.1% practiced social isolation, 72.6% were employed/studying, at least 15% presented severe or extremely severe levels of emotional distress and presence of powerful (34.1%) and severe impact event (15%). During the outbreak, 53.2% perceived feeling worse and 31.8% reported that orofacial pain started or worsened after the pandemic outbreak. Gender was associated with "social class" (P=0.036), "pain/stiffness in the jaw on awakening" (P=0.037), "change of pain during jaw habits" (P=0.034) and "perception of change in the situations mentioned in the TMD-Pain Screener" (P=0.020), "depression" (P=0.012), "anxiety" (P=0.006) and "impact of the event" (P=8.3E-11). Social isolation had a lesser chance to change the routine, to be practiced by the unemployed/not studying, and to be practiced by men (all with P<0.001). Associations were found between social class and all subscales of the DASS-21 and IES, all with P<0.001. Conclusions The practice of social isolation has social determinants. High levels of psychological and event impacts were detected. The presence of orofacial pain seemed to increase during the health crisis, and there were gender differences in the response to the COVID-19 pandemic.

Analysis of Color and Hardness of a Medical Silicone with Extrinsic Pigmentation after Accelerated Aging.

OBJECTIVE: The aim of this study is to evaluate the color alteration and shore A hardness of a medical silicone with extrinsic pigmentation, before and after accelerated aging. MATERIALS AND METHODS: Twenty samples (Silastic Q7-4735) were made with an intrinsic pigmentation. This intrinsic pigmentation was composed of a pink pigment (H-109-P, Factor II) and an opacifier (ZnO). All samples had standardized dimensions (45-mm diameter and 2-mm thickness). Half of the 20 samples manufactured subsequently received an extrinsic pigment (Tan FE-215, Factor II). Therefore, two groups were created (n = 10): Group 1, group with intrinsic pigmentation and without extrinsic pigmentation (control) and Group 2, group with intrinsic and extrinsic pigmentation. Samples were submitted to color and Shore A hardness tests, before and after 1,008 hours of aging. STATISTICAL ANALYSIS: Color alteration data were submitted to Student's t-test (α = 0.05). Shore A hardness data were submitted to two-way analysis of variance and Tukey test (α = 0.05). RESULTS: The incorporation of the extrinsic pigment on the silicone did not affect its color (ΔE) when the two groups were compared (p = 0.232). Regarding the hardness test, the interaction between group and period did not interfere with the hardness results(p=0.599). However, the period factor showed that there was a reduction in the hardness of the silicone after aging (p < 0.05). CONCLUSION: In this study, all the hardness and color results of the silicone used were clinically acceptable, regardless of the presence of extrinsic pigmentation.

Influence of length, diameter and position of the implant in its fracture incidence: A Systematic Review.

Background. Implant fractures can cause difficult problems for patients and dentists. This systematic review aimed to determine the influence of some implant parameters on the occurrence of their fracture and to determine the incidence of fractures reported in recent years. Methods. A search was conducted in Pubmed database, from which 12 studies published in the last 12 years were selected. Results. This review reported a 2% incidence of implant fracture. Most implants had been in function between 3 and 4 years until fracture. The studies did not provide necessary information to establish a relationship between the different parameters of implants and the incidence of fractures. Conclusion. Thus, the indication of type, diameter and length of an implant and the bone quality in the region receiving it should be studied and accurately examined for each individual case in order to avoid future failures.

Classification, History, and Future Prospects of Maxillofacial Prosthesis.

This review presents a classification system for maxillofacial prostheses, while explaining its types. It also aims to describe their origin and development, currently available materials, and techniques, predicts the future requirements, and subsequently discusses its avenues for improvement as a restorative modality. A literature search of the PubMed/Medline database was performed. Articles that discussed the history, types, materials, fabrication techniques, clinical implications, and future expectations related to maxillofacial prostheses and reconstruction were included. Fifty-nine articles were included in this review. Maxillofacial prostheses were classified as restorative or complementary with subclassifications based on the prostheses finality. The origin of maxillofacial prostheses is unclear; however, fabrication techniques and materials have undergone several changes throughout history. Currently, silicones and acrylic resins are the most commonly used materials to fabricate customized prostheses. Maxillofacial prostheses not only restore several types of orofacial defects but also improve the patients' quality of life. Although the current clinical scenario concerning the field of maxillofacial prostheses is promising, improvements in material quality and techniques for maxillofacial prostheses may be expected in the future, to produce better results in the treatment of patients.

Can Nonthermal Plasma Improve the Adhesion between Acrylic Resin for Ocular Prostheses and Silicone-Based Relining Material?

PURPOSE: To investigate the influence of nonthermal plasma (NTP) treatment on the tensile bond strength between heat-polymerized acrylic resin for ocular prostheses and silicone reliner, with and without the use of an adhesive primer. MATERIALS AND METHODS: One-hundred and sixty-four acrylic resin specimens were fabricated and randomly distributed into four groups according to the type of surface treatment: Sofreliner Primer, NTP, Sofreliner Primer + NTP, and NTP + Sofreliner Primer. Two specimens interposed with relining material (Sofreliner) formed one test sample to perform the tensile bond strength tests, before (initial) and after storage (final) in saline solution (37°C, 90 days, n = 10). Surface characterization was performed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The failure type was classified as cohesive, adhesive, or mixed. The data were analyzed statistically using the two-way ANOVA and Tukey test, as well as the chi-squared test (α = 0.05), Bonferroni correction (α = 0.005), and Spearman correlation coefficient (α = 0.05). RESULTS: The SEM and EDS analyses showed the presence of a thin, homogenous organic film in the groups treated with NTP. The NTP + Sofreliner Primer group presented the largest bond strength mean values in the initial period (p < 0.05). Sofreliner Primer and NTP + Sofreliner Primer groups presented the first and second largest tensile bond strength mean values in the final period (p < 0.05), respectively. NTP + Sofreliner Primer group also had the largest number of cohesive (70%, initial) and mixed (90%, final) failures. CONCLUSIONS: The NTP treatment performed before the primer application enhanced the bond between the acrylic resin ocular prosthesis and the Sofreliner silicone-based reliner, even after 90 days of immersion in saline solution.

Does pain in the masseter and anterior temporal muscles influence maximal bite force?

OBJECTIVE: The aim of this study was to evaluate changes in pain and muscle force, and the relationship between them, in patients with muscle pain and bruxism, prior to and after treatment. METHODS: Thirty women with bruxism and myofascial pain (Ia) were included in this study. Sleep bruxism diagnosis was made based on clinical diagnostic criteria, and awake bruxism diagnosis was made by patient questionnaires and the presence of tooth wear. The diagnosis of myofascial pain was established according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC-TMD). Dentulous or partially edentulous patients (rehabilitated with conventional fixed prostheses) were included in the study according to the inclusion and exclusion criteria. The pain treatment protocol included occlusal splints, patient education, and physiotherapy for 30days. Bite force was measured using a dynamometer at the central incisor and the first molar regions on both sides. The exams were performed at baseline, after 7days, and 30days after treatment. The Wilcoxon test was used to compare patient pain level response among the periods analyzed in the study. Bite force data were submitted to two-way repeated-measures ANOVA, followed by the Tukey HSD test (p<0.05). A simple regression analysis was performed to verify the relation between pain level and bite force. RESULTS: Results revealed that there was a statistical difference in pain level over time for both muscles and sides (p<0.01). In the molar region, the bite force exhibited significantly higher values after 30days of treatment, when compared with the baseline (p<0.001). There was a correlation between pain level and bite force only for the temporal muscle in all periods analyzed (p<0.05). There was no strong correlation in the response level points to support the association of pain and bite force. CONCLUSIONS: Pain level decreased and bite force increased in the molar region after treatment. No strong correlation or dispersion in the relationship between pain levels and bite force was seen in women with myofascial pain and bruxism.