OBJECTIVE: To investigate the correlation between the clinical diagnostic criteria of sleep bruxism and the frequency of mandibular movements during sleep. METHODS: Video polysomnography was used to record 20 healthy adults with at least one of the following clinical symptoms and signs: 1) report of frequent tooth grinding; 2) tooth wear and dentin exposure with at least three occlusal surfaces; 3) masticatory muscle symptoms in the morning; 4) masseter muscle hypertrophy. The rhythmic masticatory muscle activity (RMMA) and isolated tonic activity were scored to compare the correlations with clinical symptoms and signs. Finally, the incidence of temporomandibular disorders (TMD) was investigated in patients with isolated tonic and RMMA subjects. RESULTS: Among the 20 subjects, RMMA events were observed (5.8±3.1) times·h⁻¹ and isolated tonic episodes were observed (2.1±0.9) times·h⁻¹. The frequency of RMMA events was significantly greater in the patients with acoustic molars than in those without (P<0.05). Similarly, the frequency of RMMA events was significantly greater in the patients with tooth attrition than in those without (P<0.05). However, no difference was observed between the occurrence of RMMA and the symptoms of masticatory muscles or masseter hypertrophy in the morning. The incidence of TMD was significantly higher in the patients with RMMA than in the isolated tonic patients. CONCLUSIONS The clinical symptoms and signs often used to diagnose sleep bruxism are different clinical and physiological mandibular movements during sleep. RMMA during sleep can reflect the occurrence of tooth attrition and the high risk of TMD.
Adult ; Electromyography ; Humans ; Masticatory Muscles ; Polysomnography ; Sleep ; Sleep Bruxism ; Tooth Attrition

BACKGROUND: After tooth extraction, pain due to dry socket and pain in the adjacent tooth are common. The aim of this study was to retrospectively analyze pain in the adjacent tooth after surgical extraction of the mandibular third molar. METHODS: Postoperative pain due to dry socket, pain in the adjacent tooth, and pain from other causes were present. Group A included patents with dry socket alone; group B included patients with pain in the adjacent tooth alone; and group C included patients with both. The duration of symptoms was recorded. In addition, the prognosis of pain was divided into the complete improvement, improvement, maintenance, deterioration, and complete deterioration groups. RESULTS: A total of 312 mandibular third molars were extracted from 13, 60, and 10 patients in groups A, B, and C, respectively. The mean duration of symptoms was 5 days in group A and B and 15.2 days in group C. There were statistically significant differences in the duration of symptoms between groups A and C and groups B and C. CONCLUSION: Pain in the adjacent tooth after third molar extraction can be caused by inflammatory reactions and pressure on this tooth. The pain caused by pressure on the periodontal ligament and alveolar bone results from the cytokines released by osteoclasts, which are responsible for bone destruction. However, pain from periodontal ligament damage caused by excessive pressure may be misunderstood as pulpal pain. Unconscious parafunctional habits, such as clenching and bruxism, could also be associated with post-extraction pain.
Bruxism ; Cytokines ; Dry Socket ; Humans ; Molar, Third ; Osteoclasts ; Pain, Postoperative ; Periodontal Ligament ; Prognosis ; Retrospective Studies ; Tooth Extraction ; Tooth ; Weight-Bearing

OBJECTIVE: To establish a complete workflow of digital design and manufacturing occlusal splint for sleep bruxism, which can be preliminarily applied in clinical use, thus observe the clinical efficacy. METHODS: Twenty-four patients with sleep bruxism were recruited in the study and randomly divided into two groups by using random number tables. Digital-occlusal-splint (experimental group) treatment plan and traditional-occlusal-splint (control-group) treatment plan were carried out for each group, respectively. For experimental group, digital models of patients' both dental arches and the occlusion relationship after elevation were captured using an intraoral scanner. The occlusal splint was carried out by computer aided design/computer aided manufacturing (CAD/CAM), including splint designing and milling. For control group, the traditional soft occlusal splint was fabricated by vacuum laminator. The two kinds of occlusal splints were tried in the patients from each group, and the occlusal contacts were tested respectively by T-scan analysis system, which recorded the changes of occlusal indicators in the two groups. The retention, appearance and occlusal comfort degree were evaluated by the two groups of patients. Mann-Whitney test was performed with IBM SPSS 20.0 software, and bilateral test was performed. P<0.05 was considered to be statistically significant. RESULTS: The complete workflow of digital design and manufacturing occlusal splint was successfully established. During the clinical use, there was no statistical difference in the retention evaluation of two kinds of occlusal splints between the two groups of patients (Z=-0.538, P=0.590). The appearance score (Z=2.038, P=0.042) and the occlusal comfort score (Z=-2.579, P=0.010) of the experimental group were higher than those of the control group, with statistically significant differences. The T-scan analysis results showed that only the second molar on both sides of the traditional occlusal splint had occlusal contact in intercupsal position, while the digital occlusal splint had stable and bilaterally balanced contact between the maxillary and mandibular teeth. Furthermore, the occlusal force was uniformly distributed in the experimental group. CONCLUSION The complete workflow of digital occlusal splint improves the occlusal design, greatly simplifies and optimizes the traditional process of making occlusal splint. This new method is resource-saving and environmental-friendly, and it is able to serve patients more conveniently and efficiently.
Dental Arch ; Dental Occlusion ; Humans ; Occlusal Splints ; Sleep Bruxism ; Workflow

PURPOSE: This study was performed to investigate the relationship between sleep bruxism (SB) and pulpal calcifications in young women. MATERIALS AND METHODS: A total of 100 female participants between 20 and 31 years of age who were referred to our radiology clinic for a dental check-up, including 59 SB and 41 non-SB patients, were sampled for the analysis. SB was diagnosed based on the American Academy of Sleep Medicine criteria. All teeth were evaluated on digital panoramic radiographs to detect pulpal calcifications, except third molars, teeth with root canal treatment, and teeth with root resorption. Binary logistic regression analysis was used to determine the risk factors for pulpal calcifications. The Spearman correlation coefficient was applied and the Pearson chi-square test was used for categorical variables. To test intra-examiner reproducibility, Cohen kappa analysis was applied. P values < .05 were considered to indicate statistical significance. RESULTS: A total of 2800 teeth were evaluated (1652 teeth from SB patients and 1148 from non-SB patients), and 61% of patients had at least 1 dental pulpal calcification. No statistically significant relationship was found between SB and pulpal calcifications (P>0.05). In SB patients, the total number of pulpal calcifications was 129, while in non-SB patients, it was 84. Binary logistic analysis showed that SB was not a risk factor for the presence of pulpal calcifications (odds ratio, 1.19; 95% CI, 0.52–2.69, P>.05). CONCLUSION: No relationship was found between SB and pulpal calcifications.
Dental Pulp ; Dental Pulp Calcification ; Dental Pulp Cavity ; Female ; Humans ; Logistic Models ; Molar, Third ; Radiography, Panoramic ; Risk Factors ; Root Resorption ; Sleep Bruxism ; Sleep Medicine Specialty ; Tooth

OBJECTIVES: Headache is the most common complaint of patients suffering from temporomandibular joint disorders (TMDs). Thus, temporomandibular joint (TMJ) examinations maybe necessary in patients with headache. Considering the high prevalence of bruxism and TMDs in patients with headache the effects of conservative TMD treatment on headache should be assessed. MATERIALS AND METHODS: Patients were questioned about headaches in the past three months. Those responding affirmatively to this question were examined for TMD and bruxism. After the examinations, 219 patients remained in the study and received self-management instructions. Patients were requested to modify oral habits except when eating or sleeping. The degree of pain (visual analogue scale), headache disability index (HDI), frequency of headaches (FH) per month and TMD intensity were evaluated. RESULTS: The median levels of pain, HDI, FH, and TMD intensity were 8, 44, 8, and 7, respectively, before modifying oral habits and decreased to 4, 24, 2, and 3, respectively, after intervention. These decreases were statistically significant. CONCLUSION: Having patients maintain free space between the teeth and relax muscles can be an efficient method to treat headache and TMD, especially when repeated frequently.
Bruxism ; Eating ; Headache* ; Humans ; Methods ; Muscles ; Prevalence ; Self Care ; Temporomandibular Joint ; Temporomandibular Joint Disorders ; Tooth

PURPOSE: To investigate the frequency of childhood sleep problems at pediatric clinics in Seoul and Gyeonggi provinces. METHODS: Children (n=936) and their parents who visited 5 primary and 1 secondary pediatric outpatient clinics were invited to complete a Pediatric Sleep Questionnaire. RESULTS: Among patients, 901 (96.3%) answered questionnaires in sufficient detail for evaluation. The participant's mean age was 4.35±3.02 years (range, 0–18 years). The male to female ratio was 1:0.93 (466 boys, 435 girls). Habitual snoring (>3 day/week) was reported in 16.9% of the participants. The prevalence of habitual snoring in children <2 years and those between 2–5 years was 9% and 18%, respectively. Sleep disordered breathing was found in 15.1% (106 of 700) of children >2 years. Insomnia was reported in 13.2% of children. The prevalence of sleepwalking, night terrors, and bruxism, is 1.6%, 19%, and 21.1%, respectively. Snoring was associated with increased incidence of sleepwalking, night terrors, and bruxism. Age was associated with insomnia and habitual snoring (P<0.05). Insomnia was more prevalent in younger (21%) than in older children (6%). Snoring was more frequent in both preschool (34%) and school-aged children (33%). The frequency of sleep disordered breathing and insomnia did not vary significantly with gender. However, snoring was more prevalent in boys. CONCLUSION: Sleep problems are frequent among children in Korea. Children with snoring have an increased risk of sleepwalking, night terror, and bruxism. Primary clinicians should consider children's sleep habits to improve their health.
Adolescent* ; Ambulatory Care Facilities ; Bruxism ; Child* ; Female ; Gyeonggi-do ; Humans ; Incidence ; Korea ; Male ; Night Terrors ; Parents ; Prevalence ; Seoul ; Sleep Apnea Syndromes ; Sleep Initiation and Maintenance Disorders ; Snoring ; Somnambulism

OBJECTIVES: The aim of this study was to develop a decision support model for the prediction of occlusal force from the size and color of articulating paper markings in bruxism patients. METHODS: We used the information from the datasets of 30 bruxism patients in which digital measurements of the size and color of articulating paper markings (12-µm Hanel; Coltene/Whaledent GmbH, Langenau, Germany) on canine protected hard stabilization splints were measured in pixels (P) and in red (R), green (G), and blue (B) values using Adobe Photoshop software (Adobe Systems, San Jose, CA, USA). The occlusal force (F) was measured using T-Scan III (Tekscan Inc., South Boston, MA, USA). The multiple regression equation was applied to predict F from the P and RGB. Model evaluation was performed using the datasets from 10 new patients. The patient's occlusal force measured by T-Scan III was used as a ‘gold standard’ to compare with the occlusal force predicted by the multiple regression model. RESULTS: The results demonstrate that the correlation between the occlusal force and the pixels and RGB of the articulating paper markings was positive (F = 1.62×P + 0.07×R –0.08×G + 0.08×B + 4.74; R 2 = 0.34). There was a high degree of agreement between the occlusal force of the patient measured using T-Scan III and the occlusal force predicted by the model (kappa value = 0.82). CONCLUSIONS: The results obtained demonstrate that the multiple regression model can predict the occlusal force using the digital values for the size and color of the articulating paper markings in bruxism patients.
Bite Force* ; Bruxism* ; Dataset ; Decision Making ; Decision Support Systems, Clinical* ; Decision Support Techniques ; Humans ; Logistic Models ; Occlusal Splints ; Splints

Here, the author presents a case of bruxism-induced otalgia in a 29-year-old female patient. The pain was sharp and penetrating in character. It was usually worse in the morning and frequently radiated to the right temporal area. She had received unsuccessful medical treatments for migraine headache. The otoendoscopic examination revealed a normal tympanic membrane. A thorough inspection of her teeth revealed excessive wear on the incisal edges, and the cause of her otalgia was identified as bruxism-related temporomandibular joint disorder. After the use of an occlusal splint and repeated botulinum toxin injections in the masseter and anterior temporalis muscles, along with good sleep hygiene, she experienced significant relief of pain and symptoms. The author suggests that multidisciplinary cooperation between ENT clinicians and dentists is necessary for the quick and accurate diagnosis and treatment of bruxism and the consequential referred otalgia.
Adult ; Botulinum Toxins ; Bruxism ; Dentists ; Diagnosis ; Earache* ; Female ; Humans ; Hygiene ; Migraine Disorders ; Muscles ; Occlusal Splints ; Pain, Referred ; Temporomandibular Joint Disorders ; Tooth ; Tooth Wear ; Tympanic Membrane

PURPOSE: Stress distribution and mandible distortion during lateral movements are known to be closely linked to bruxism, dental implant placement, and temporomandibular joint disorder. The present study was performed to determine stress distribution and distortion patterns of the mandible during lateral movements in Class I, II, and III relationships. METHODS: Five Korean volunteers (one normal, two Class II, and two Class III occlusion cases) were selected. Finite element (FE) modeling was performed using information from cone-beam computed tomographic (CBCT) scans of the subjects' skulls, scanned images of dental casts, and incisor movement captured by an optical motion-capture system. RESULTS: In the Class I and II cases, maximum stress load occurred at the condyle of the balancing side, but, in the Class III cases, the maximum stress was loaded on the condyle of the working side. Maximum distortion was observed on the menton at the midline in every case, regardless of loading force. The distortion was greatest in Class III cases and smallest in Class II cases. CONCLUSIONS: The stress distribution along and accompanying distortion of a mandible seems to be affected by the anteroposterior position of the mandible. Additionally, 3-D modeling of the craniofacial skeleton using CBCT and an optical laser scanner and reproduction of mandibular movement by way of the optical motion-capture technique used in this study are reliable techniques for investigating the masticatory system.
Bruxism ; Cone-Beam Computed Tomography* ; Dental Implants ; Finite Element Analysis* ; Incisor ; Malocclusion* ; Mandible ; Mastication* ; Masticatory Muscles ; Reproduction ; Skeleton ; Skull ; Stomatognathic System ; Temporomandibular Joint Disorders ; Volunteers

OBJECTIVETo determine whether there are in vivo differences of metabolites levels in bilateral cortical masticatory area(CMA) of patients with sleep bruxism, compared with healthy controls using proton magnetic resonance spectroscopy(1H-MRS). Accordingly to explore if cortical control of the central jaw motor system is abnormal in sleep bruxism patients.

METHODSFifteen sleep bruxism patients and fifteen age- and gender-matched healthy controls underwent 1H-MRS of bilateral CMA using J-difference edited point-resolved spectroscopy sequence(MEGA-PRESS) technique. Levels of metabolites were quantified from the ratio of the metabolite integral to the unsuppressed water signal. Differences of levels of γ-aminobutyric acid(GABA), glutmate(Glu) and N-acetyl aspartate(NAA) in bilateral CMA between sleep bruxism patients and healthy controls were tested using two-way ANOVA.

RESULTSEdited spectra were successfully obtained from the bilateral CMA in all of the participants. Levels of GABA+, glutmate and NAA in right and left CMA in sleep bruxism patients were (2.45±0.48)×10(-3), (2.35±0.62)×10(-3), (10.65±1.84)×10(-3), (10.49±2.37)×10(-3), (10.70±3.61)×10(-3), and (11.26±4.01)×10(-3) respectively. In contrast, levels of GABA+, glutmate and NAA in right and left CMA in healthy controls were (2.63±0.68)×10(-3), (2.65±0.97)×10(-3), (11.19± 1.34)×10(-3), (10.58±3.14)×10(-3), (11.82±1.80)×10(-3), and (11.95±3.23)×10(-3). There were no differences in levels of GABA+(P=0.196), Glu(P=0.590), and NAA(P=0.292) between sleep bruxism patients and healthy controls, nor in inbilateral CMA(GABA+: P=0.837; Glu: P=0.510; NAA: P=0.628).

CONCLUSIONSThe results indicate the absence of any alteration of the cortical control of the central jaw motor system in the levels of GABA, Glu and NAA in patients with sleep bruxism.

Analysis of Variance ; Aspartic Acid ; analogs & derivatives ; analysis ; metabolism ; Case-Control Studies ; Glutamic Acid ; analysis ; metabolism ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; methods ; Masticatory Muscles ; metabolism ; physiopathology ; Motor Neurons ; metabolism ; Sleep Bruxism ; metabolism ; physiopathology ; gamma-Aminobutyric Acid ; analysis ; metabolism