Prevalence and associated factors of myofascial pain in orthognathic patients with skeletal class II malocclusion

The prevalence of masticatory muscle pain in healthy individuals with class I and class II malocclusion: a cross-sectional study

Introduction

The etiopathogenesis of TMD is complex and involves multiple factors. The role of occlusal abnormalities in the painful form of TMD remains controversial. This study aimed to determine the prevalence of myalgia in patients with class I and class II malocclusion.

Materials and methods

A total of 256 generally healthy patients, aged 25-30, with class I and class II malocclusion, were examined. Medical histories and physical examinations were conducted using the DC/TMD Form. Based on the clinical findings, the patients were divided into three groups: Group I consisted of patients with class I malocclusion; Group II included patients with class II malocclusion and proclined incisors; and Group III comprised patients with class II malocclusion and retruded incisors. Within each group, cases with muscle pain and those without were identified based on the data from the DC/TMD Form.

Results

All studied groups (Groups I, II, and III) showed a high incidence of myalgia. However, statistical analysis did not show a significant difference in the overall occurrence of muscle pain between the groups, nor were there significant differences in pain incidence when examining individual muscles among the groups.

Conclusion

No association was found between malocclusion and the occurrence of muscle pain. However, the more frequent presence of symptoms related to functional disorders, such as myalgia, highlights the need for screening and treatment even in generally healthy patients.

A case-control study on the effect of rhythmic masticatory muscle activity (RMMA) clusters on sleep fragmentation and severity of orofacial muscle pain in sleep bruxism

Rhythmic masticatory muscle activity (RMMA) is a periodic muscle activity that characterises sleep bruxism (SB) events. These can occur as a single event, in pairs, or in clusters. Since RMMA episodes often occur in clusters and the relevance of this occurrence is unknown, we conducted a study to investigate the effect of RMMA clusters on sleep fragmentation and the severity of orofacial muscle pain. This study involved a secondary analysis using data from 184 adult subjects with orofacial muscle pain who underwent definitive polysomnography (PSG) for sleep bruxism diagnosis. Self-reported orofacial muscle pain (OFMP) was assessed using the numeric rating scale, and additional evaluation of side-to-side equivalence (symmetry) was described using a binary system. Among the 184 participants, 60.8% (n = 112) did not exhibit clusters and among the 72 participants with clusters, 36.1% (n = 26) and 63.9% (n = 46) were in the high and low RMMA frequency groups, respectively. The high SB group had significantly three times more phasic RMMA events than the noncluster group. A total of 89.67% (n = 165) of subjects reported orofacial muscle pain. While there was no difference in the severity of OFMP among groups, a significant decrease in symmetry between the severity of temporal muscle pain on the left and right sides was noted in the cluster group compared with the noncluster group. Clustering of RMMA events is associated with sleep fragmentation. The asymmetry of temporal muscle pain is related to the presence of RMMA clusters in sleep bruxism.

Condylar Positional Changes in Skeletal Class II and Class III Malocclusions after Bimaxillary Orthognathic Surgery

Orthognathic surgery is indicated to modify the position of the maxillomandibular structure; changes in the mandibular position after osteotomy can be related to changes in the position of the mandibular condyle in the articular fossa. The aim of this study was to determine changes produced in the mandibular condyle 6 months after orthognathic surgery. A cross-sectional study was conducted that included subjects who had undergone bimaxillary orthognathic surgery to treat dentofacial deformity of Angle class II (group CII) or Angle class III (group CIII). Standardized images were taken using cone-beam computed tomography 21 days before surgery and 6 months after surgery; measurement scales were used to identify the condylar position and its relations with the anterior, superior, and posterior joint spaces. The results were analyzed using the Shapiro-Wilk and Student's t-tests, while considering a value of p < 0.05 as indicating a significant difference. Fifty-two joints from 26 patients, with an average age of 27.9 years (±10.81), were analyzed. All subjects in both group CII and group CIII showed a significant change in the anterior, superior, and posterior joint spaces. However, postoperative changes in the position of the condyle in the articular fossa were not significant in the anteroposterior analysis. We conclude that orthognathic surgery causes changes in the sagittal position of the mandibular condyle in subjects with mandibular retrognathism and prognathism.

The Cognitive and Emotional Aspect in Fibromyalgia: The Importance of the Orofacial Sphere

Fibromyalgia syndrome (FMS) is a systemic and multifactorial disease of unknown etiology. There are many co-morbidities that the patient presents, making the clinical picture not immediate. Cognitive decline and emotional alteration (anxiety and depression) are found in fibromyalgic patients, as well as temporomandibular joint arthrokinematic disorders, dental malocclusion, and periodontitis. There seems to be a biunivocal relationship between oral and psychiatric dysfunctions in fibromyalgia. The article reviews the information regarding oral health alterations with respect to the patient's cognitive and emotional response, as the most recent information we have raises new hypotheses about the diagnosis of FMS.

Genetic polymorphisms are involved in oral health-related quality of life in skeletal class III patients submitted to orthognathic surgery

OBJECTIVE

This study aimed to evaluate whether sex and genetic polymorphisms impact the oral health-related quality of life (OHRQoL) preoperatively and the difference between preoperative and postoperative OHRQoL in skeletal Class III patients submitted to orthognathic surgery.

MATERIALS AND METHODS

This longitudinal study consisted of ninety-nine patients with skeletal Class III malocclusion who required orthognathic surgery. The Oral Health Impact Profile-14 (OHIP-14) is a questionnaire used to assess the OHRQoL with a 5-point Likert-type scale, covering seven domains related to physical and psychosocial factors. The questionnaire was applied in the preoperative and postoperative periods, and the difference scores were calculated to assess the OHRQoL after orthognathic surgery. The DNA was extracted from oral mucosa cells to evaluate genetic polymorphisms in ANKK1, DRD2, ESR1, and ESR2 through real-time PCR.

RESULTS

There was an improvement in all OHRQoL domains following orthognathic surgery (p < 0.05). In the preoperative evaluation, women presented worse OHRQoL (p < 0.05) than men. There was no statistical difference between sex and the OHRQoL after surgery (p > 0.05). When evaluating the polymorphisms and preoperative OHIP-14 scores, CT genotype patients for rs1800497 (ANKK1) had a worse perception of the physical pain domain than CC genotype (p = 0.026), and CC genotype patients for rs1256049 (ESR2) had a worse perception of the functional limitation domain than CT genotype (p = 0.002). In the analysis between polymorphisms and postoperative and preoperative difference scores, CT genotype patients for rs1256049 (ESR2) had a greater improvement in the perception of the physical pain domain than the CC genotype (p = 0.031). In rs6275 and rs6276 (DRD2), patients with the CC genotype worsened the perception of the functional limitation domain than the TT genotype (p = 0.045), and AA genotype patients worsened the perception of the functional limitation domain than GG genotype (p = 0.048) after surgery, respectively. In addition, patients with the CT genotype for rs1800497 (ANKK1) had a greater improvement of OHRQoL perception in the total scale than the TT genotype (p = 0.018), and CT genotype patients had a greater improvement in the perception of function limitation domain than TT genotype (p = 0.017).

CONCLUSION

Women have a worse perception of OHRQoL in the preoperative period of orthognathic surgery. Furthermore, polymorphisms in the ANKK1, DRD2, and ESR2 genes could be involved with OHRQoL in the preoperative period and following orthognathic surgery.

CLINICAL RELEVANCE

The knowledge of the genetic background concerning OHRQoL in skeletal class III patients would aid in clinical practice to screen for associated genetic factors and prevent OHRQoL deterioration, especially after orthognathic surgery, considering that patients' genetic profiles would soon be available.

What factors predict craniomandibular disorders in severe COVID-19 survivors after prolonged intubation?

PURPOSES

To estimate and identify predictors of craniomandibular disorders (CMDs) in severe COVID-19 survivors after prolonged intubation ≥ 1 week (SCOVIDS-PI).

METHODS

This retrospective study enrolled two cohorts of SCOVIDS-PIs with vs. without CMD during a one-year period. The predictor variables were demographic, dental, anesthetic, and laboratory parameters. The main outcome was presence of CMD until six post-PI months (yes/no). Appropriate statistics were computed with α = 95%.

RESULTS

The sample comprised 176 subjects aged 59.2 ± 17.2 years (range, 27-89; 11.9% with CMDs; 30.1% females). CMDs were significantly associated with (1) bilateral posterior tooth loss (P = 0; number needed to screen [NNS] = 1.6), (2) dentofacial skeletal class II/convex face (P = .01; NNS = 2.2), and (3) peak CRP during intensive care ≥ 40 mg/l (P = .01; NNS = 3.5). With combined predictors, NNS became 2 to 4.3.

CONCLUSIONS

Three predictors of CMDs in SCOVIDS-PIs: bilateral molar loss, convex face, and CRP ≥ 40 mg/l, indicate CMD screening and/or referral to a CMD specialist, regardless of patients' age, gender, underlying CMDs, or previous dental checkups. Screening ∼2 to 4 "SCOVIDS-PIs with ≥ one predictor" will identify one CMD events/patients during the first six post-PI months.