Impact of bruxism on craniomandibular morphology: A cone-beam computed tomographic study

Self -reported bruxism in patients undergoing Orthodontic treatment - a cross-sectional study

BACKGROUND

Orthodontic treatment involves manipulation of tooth position that can temporarily lead to occlusal interferences capable of inducing bruxism. The objectives of this study were to determine the self-reported incidence of bruxism and its association with factors such as facial type, divergence, skeletal and dental malocclusions in orthodontic patients.

MATERIALS AND METHODS

80 patients who underwent a minimum of six months of orthodontic treatment were surveyed using a validated self-reported bruxism questionnaire for the presence or absence of bruxism. Data regarding patients' facial type, divergence, skeletal and dental malocclusions were measured and collected from the patients' orthodontic records. Binomial logistic regression analysis was used to assess the association of these factors with bruxism.

RESULTS

About 45% of the orthodontic patients reported bruxism after the commencement of orthodontic treatment. The median age of the sample was 19.8 (17.7, 24.3) years and 60% of them were women. Binomial logistic regression analysis showed an insignificant association of gender and age with bruxism. When analyzing the association with facial type, divergence, skeletal and dental malocclusion no statistically significant association was found. However, patients with hypodivergent face [odds ratio (OR) = 2.4; 95% confidence interval (CI) = 0.7-8.5] and dental class III [OR = 4.0; 95% CI = 0.3-51.0] were more likely to report bruxism after the initiation of orthodontic treatment. A statistically significant association was found with jaw fatigue or soreness upon awakening (28.7%), clenching (27.5%) and grinding (25%) in the bruxism group (p-value ≤ 0.001). Teeth and gum soreness were also significantly associated with bruxism, affecting 25% of the orthodontic patients (p-value ≤ 0.001). On the contrary, nocturnal grinding (10%) and temporal headaches (21.3%) were negatively correlated with bruxism.

CONCLUSIONS

There is a risk of bruxism among orthodontic patients, with 45% of them reporting bruxism following the initiation of treatment. Patients with bruxism commonly reported jaw fatigue or soreness upon awakening, clenching, grinding, teeth and gum soreness. Factors such as facial type, facial divergence, skeletal and dental malocclusions have no impact on the onset of bruxism during orthodontic treatment.

Prevalence and correlation with sex, age, and dental status of bone apposition at the mandibular angle and radiographic alterations of the temporomandibular joints: a retrospective observational study in an adult Swiss population

BACKGROUND

The purpose of this study was to determine the prevalence of radiographic changes in the mandibular angle (bone apposition) and osseous alterations in the temporomandibular joints (TMJs) in the adult population of Switzerland. In addition, the study intended to investigate possible correlations between the two sites of contour bone changes (mandibular angle and TMJ) and to analyze various patient-related factors, including sex, age, dental status, and medical history.

METHODS

Panoramic radiographs of 600 patients distributed into six age groups (283 females, 317 males, aged 20 to 79 years) were included to evaluate radiographic changes. The bone in the mandibular angle region and the shape of the condylar heads were examined for contour changes (bone apposition at the jaw angles and osseous changes of the TMJs). General estimating equations, binormal tests, and chi-squared tests were used for statistical analysis.

RESULTS

Approximately half of the mandibular angles (47.8%) showed bone apposition, mostly bilateral. TMJ alterations were less common (27%), often unilateral, with flattening being the most frequent finding. No significant correlation was found between the two sites. Bone apposition at the mandibular angle showed a significant male predominance, whereas TMJ changes did not differ by sex. Alterations in both sites increased with age, and were not related to dental status or analgesic use.

CONCLUSIONS

Bone apposition at the mandibular angle should be interpreted as part of the natural functional adaptation of the bone associated with aging. Assuming that parafunctional habits may influence the development and progression of alterations in the mandibular angle or TMJs, the presence of radiographic changes in these areas should prompt dental clinicians to investigate further in this direction.

TRIAL REGISTRATION

The study was approved by the Swiss Association of Research Ethics Committees (swissethics), BASEC reference number: 2020-00963 (25.05.2020).

Relationship between bruxism and mandibular bone modifications based on medical imaging: a scoping review

OBJECTIVES

This scoping review aimed to assess the current state of knowledge regarding the relationship between bruxism and changes in density or volume of mandibular bone, based on medical imaging.

METHODS

Literature review was conducted following the PRISMA-ScR protocol. PubMed, Web of Science and Cochrane library databases were searched for peer-reviewed articles by two blinded reviewers. Studies based on the evaluation of mandibular bone density and/or bone volume with imaging examination in adult patients were examined. The selected articles were summarized in PICOS tables and assessed for methodological quality.

RESULTS

Nine articles were included, according to the inclusion criteria. They showed that bruxer patients had more bony exostoses of the mandibular angle, smaller condyles, and morphological changes for cancellous and cortical mandibular bone compared to non-bruxer patients.

CONCLUSION

Bruxism seems to induce morphological and anatomical changes in the different regions of the mandibular bone (condyles, mandibular angle, mandible body). Given the heterogeneity of the included studies, these results should be interpreted with caution. Further studies are needed to support these results, in particular via the analysis of three-dimensional imaging to overcome the limitations of panoramic radiograph.

Morphological evaluation of gonial and antegonial regions in bruxers on panoramic radiographic images

BACKGROUND

This is the first study to report both cortical and trabecular bone evaluation of mandibles in bruxers, within the knowledge of the authors. The purpose of this study was to evaluate the effects of bruxism on both the cortical and the trabecular bone in antegonial and gonial regions of the mandible, which is the attachment of the masticatory muscles, by using panoramic radiographic images.

METHODS

In this study, the data of 65 bruxer (31 female, 34 male) and 71 non-bruxer (37 female, 34 male) young adult patients (20-30 years) were evaluated. Antegonial Notch Depth (AND), Antegonial-Index (AI), Gonial-Index, Fractal Dimension (FD) and Bone Peaks (BP) were evaluated on panoramic radiographic images. The effects of the bruxism, gender and side factors were investigated according to these findings. The statistical significance level was set atP ≤ 0.05.

RESULTS

The mean AND of bruxers (2.03 ± 0.91) was significantly higher than non-bruxers (1.57 ± 0.71; P < 0.001). The mean AND of males was significantly higher than females on both sides (P < 0.05). The mean AI of bruxers (2.95 ± 0.50) was significantly higher than non-bruxers (2.77 ± 0.43; P = 0.019). The mean FD on each side was significantly lower in bruxers than in non-bruxers (P < 0.05). The mean FD of males (1.39 ± 0.06) was significantly higher than females (1.37 ± 0.06; P = 0.049). BP were observed in 72.5% of bruxers and 27.5% of non-bruxers. The probability of existing BP, in bruxers was approximately 3.4 times higher than in non-bruxers (P = 0.003), in males was approximately 5.5 times higher than in females (P < 0.001).

CONCLUSION

According to the findings of this study, the morphological differences seen in cortical and trabecular bone in the antegonial and gonial regions of the mandible in bruxers can be emphasized as deeper AND, higher AI, increased of existing BPs, and lower FD, respectively. The appearance of these morphological changes on radiographs may be useful for indication and follow-up of bruxism. Gender is an effective factor on AND, existing BP and FD.