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

PURPOSE: Aims to analyze the occlusal wear patterns in maxillary posterior teeth with palatal side abfractions and study the association between occlusal force and abfractions. MATERIALS AND METHODS: This study was conducted in a total of 308 teeth from 148 patients with palatal side abfractions in maxillary posterior teeth. The occlusal wears in maxillary premolars and molars with palatal side abfractions were classified and recorded. The classification was done by type of teeth, age, and gender, and in order to evaluate the statistical significance between groups, chi-square test was conducted (α = 0.05). RESULTS: Palatal side abfractions in maxillary posterior teeth were observed at the highest frequency in the 1st molars, and in all teeth with palatal side abfractions, more than one occlusal wear was observed. In classification by type of teeth, by age, and by gender, the occlusal wears in teeth with palatal side abfractions were observed at high frequency in cuspal inclined plane, central fossa, and marginal ridge, and there was a statistical significance (P < 0.05). CONCLUSION: Palatal side abfractions were observed at the highest frequency in maxillary 1st molars, and in all maxillary posterior teeth where palatal side abfractions were found, the occlusal wears were observed. And the occlusal wears were observed at high frequency in cuspal inclined plane, central fossa and marginal ridge. Such results show that abfraction is associated with occlusal force.
Bicuspid ; Bite Force ; Classification ; Humans ; Molar ; Tooth Attrition ; Tooth Fractures ; Tooth

Severe dental attrition causes pathological changes of the tooth, collapsed occlusion, and functional and aesthetic complications and can also result in a decrease in occlusal vertical dimension. Before increasing the vertical dimension with full-mouth rehabilitation, it is important to determine the amount of vertical dimension through accurate diagnosis. In this case, a 77 year old elderly male patient on anticoagulant medication with generalized attrition and fracture of teeth was treated with full-mouth rehabilitation in order to recover vertical dimension and aesthetics. Accurate clinical and radiographic examination, diagnostic, wax-up, and occlusal vertical dimension evaluation were step by step performed considering pre-medical history and old age. Patient adaptability was evaluated using an occlusal splint and interim restoration. After 3 months of stabilization with interim restoration, definitive prostheses were fabricated. Satisfactory functional and esthetic outcomes are observed after 6 months of follow up.
Aged ; Dentition ; Diagnosis ; Esthetics ; Follow-Up Studies ; Humans ; Male ; Mouth Rehabilitation ; Mouth ; Occlusal Splints ; Prostheses and Implants ; Rehabilitation ; Tooth ; Tooth Attrition ; Vertical Dimension

A non-physiological occlusal plane caused by continuous tooth loss, occlusal wear, and failure of a prosthesis may result in an unattractive appearance and functional problems, such as reduced masticatory efficiency and occlusal interference. Therefore, when undertaking prosthetic treatment for edentulous patients or patients with a collapsed occlusal plane, it is important to establish an occlusal plane that is compatible with masticatory function. The patient in this case report had undergone restoration of a completely edentulous maxilla using an implant-supported fixed prosthesis. On follow-up examination in the following 6 years, mechanical complications were observed in the existing implant prosthesis, including porcelain chipping, occlusal wear, and screw loosening. Moreover, due to occlusal wear and supraeruption of the opposing anterior teeth, as well as loss of some posterior teeth, the occlusal plane had collapsed. Following diagnosis, the patient underwent full mouth rehabilitation, involving additional implant installation in edentulous sites, recreation of the existing prosthesis, and prosthetic restoration of all remaining teeth.
Dental Occlusion* ; Dental Porcelain ; Diagnosis ; Follow-Up Studies ; Humans ; Maxilla ; Mortuary Practice ; Mouth Rehabilitation ; Prostheses and Implants* ; Recreation ; Tooth ; Tooth Attrition ; Tooth Loss

Multiple tooth loss and excessive occlusal wear can result in damage to occlusal disharmony, functional disorders and esthetic problems, requiring comprehensive prosthetic treatments. Changing vertical dimension harmonized with surrounding muscle tissue is important. In this case, the patient with loss of vertical dimension caused by severe tooth loss and tooth wear was treated with the analysis of vertical dimension, such as diagnostic model, radiography and various clinical exams. the patient was satisfied with favorable functions and esthetics for 1 years of follow-up.
Esthetics ; Follow-Up Studies ; Humans ; Mouth Rehabilitation* ; Mouth* ; Radiography ; Tooth Attrition ; Tooth Loss* ; Tooth Wear* ; Tooth* ; Vertical Dimension*

PURPOSE: The purpose of this study was to compare and analyze the wear of a prosthesis for 6 months after restoration with implant-supported fixed dental prosthesis made of either zirconia or gold. MATERIALS AND METHODS: This study was conducted on patients requiring implant-supported fixed dental prostheses on first or second molar from January, 2015 to January, 2016. A total of 47 prostheses and antagonists were examined. Occlusal surface was recorded by impression of each prosthesis and antagonist 1 week and 6 months after prosthesis delivery. The digital files were created by impression scan. Occlusal shapes of 1 week and 6 months were compared and wear of prostheses and antagonists was analyzed. The Mann-Whitney test was used to analyzed the result data underwent normality test using SPSS (Version 23.0, IBM Corporation) RESULTS: Mann-Whitney test revealed that there was no statistically significant difference in the median amount of mean vertical wear for 6 months in zirconia (50.84 μm) and gold (42.84 μm) prostheses (P > 0.05). When the opposing teeth were natural, the median amount of mean vertical wear of zirconia and gold prostheses was 47.72 μm and 41.97 μm, respectively, and the median amount of mean vertical wear of enamel was 47.26 μm and 44.59 μm, respectively. Statistical analysis showed no significant difference (P > 0.05). CONCLUSION: Despite the short study period and the small number of experimental groups, zirconia and gold showed no significant difference in wear during the first 6 months. Opposing natural enamel also showed no significant difference in the wear.
Clinical Study ; Dental Enamel ; Dental Prosthesis ; Humans ; Molar ; Prostheses and Implants ; Tooth ; Tooth Attrition

Excessive occlusal wear can result in unacceptable damage to the residual teeth structure, anterior guidance and masticatory function. An 86-year-old man presented with worn dentition and anterior deep bite due to loss of the posterior support. Two implants covered by Korean national health insurance, fixed partial denture and direct composite resin were used to restore the dentition, instead of removable prosthesis. The occlusal vertical dimension was increased by 2 mm in the premolar area and shortened dental arch concept was applied. This treatment was a less expensive alternative to full-mouth rehabilitation with positive esthetic and functional outcomes after 7 months of follow-up.
Aged, 80 and over ; Bicuspid ; Dental Arch* ; Dental Implants ; Dentition* ; Denture, Partial, Fixed ; Follow-Up Studies ; Humans ; National Health Programs ; Overbite ; Prostheses and Implants ; Rehabilitation ; Tooth ; Tooth Attrition ; Tooth Wear ; Vertical Dimension*

OBJECTIVES: No evidence has been found on various types of dental erosion, except for occupational dental erosion. This study aimed to evaluate the distribution of four types of dental erosion (occupational, dietary, systemic, and gastric) and its associated factors among workers in factories that use acids. METHODS: Of 89,034 workers from 4,625 factories that use acids, 716 workers from 38 factories were selected for this cross-sectional epidemiological study by using three-stage stratified cluster sampling. Evaluation for dental erosion was performed by a trained dentist by using Kim's criteria, and a saliva sample was collected directly from each participant. Data on acid sources and associated factors were collected by using questionnaires. By using a complex sample analysis, the T test and Rao-Scott chi-square test were applied to analyze the distribution of four acid factors and to evaluate the associated factors. RESULTS: The prevalence of overall dental erosion was 37.7% for occupational dental erosion, 23.1% for dietary dental erosion, 3.1% for systemic dental erosion, and 3.2% for gastric dental erosion. The prevalence of severe dental erosion was 10.5% for occupational dental erosion, 7.1% for dietary dental erosion, 1.8% for systemic dental erosion, and 1.7% for gastric dental erosion. The factors associated with dental erosion were age, sex, acid exposure, dental cervical abrasion, and dental attrition. CONCLUSIONS: Our data showed that the prevalence of dental erosion was high, moderate, and low in occupational, dietary, and gastric and systemic dental erosions, respectively, among workers exposed to acids. The related factors differed according to the types of dental erosion. Our data suggested that different types of promotion programs for dental erosion should be considered according to acid source.
Dentists ; Epidemiologic Studies ; Epidemiology ; Humans ; Prevalence ; Saliva ; Tooth Attrition

Severe dental attrition causes pathological changes of the tooth, imbalanced occlusion, and functional and aesthetic complications and can also result in a decrease in occlusal vertical dimension that can incur temporomandibular joint and muscular complications. Before restoring the vertical dimension with full-mouth prosthetic restorations, it is important to determine the amount of vertical lifting through complete diagnosis. In this study, a 59 year-old male patient with generalized attrition and fracture of teeth was treated with full-mouth zirconia prosthetic restoration in order to recover vertical dimension and aesthetics. Through the analysis of physiologic rest position and inter-canine distance, the treatment was planned for lifting 3 mm in vertical dimension. Interim crown were fabricated after full-mouth wax up, having the patient use for 6 months. The final monolithic and bilayered zirconia restorations were completed. The patient showed satisfaction in function and aesthetics for 18 months of follow-up since delivering the final restorations.
Crowns ; Diagnosis ; Esthetics ; Follow-Up Studies ; Humans ; Lifting ; Male ; Mouth Rehabilitation* ; Mouth* ; Temporomandibular Joint ; Tooth Attrition ; Tooth Fractures* ; Tooth Wear* ; Tooth* ; Vertical Dimension*

Excessive occlusal wear causes loss of tooth structure, occlusal plane disharmony, impaired function and esthetic problems. Although the decrease of occlusal vertical dimension may be compensated by the growth of alveolar bone and tooth eruption, minimal increase of occlusal vertical dimension may be required for esthetics and retention of prosthesis. In this case, a 44-year-old male patient visited Seoul National University Dental Hospital with chief complaint of severe tooth wear and shade disharmony. Based on assessment of diagnostic wax-up, 3 mm increase of occlusal vertical dimension was determined. Removable occlusal splint and interim prosthesis was used to ascertain patient's comfort and adaptation. After the adaptation period, definitive prosthesis fabricated with full-contour monolithic zirconia were delivered and the patient was recommended to wear a nightguard device for prosthesis protection. This report presents a case of full mouth rehabilitation with the elevation of patient's occlusal vertical height, resulting in satisfactory esthetics and functions.
Adult ; Dental Occlusion ; Dentition* ; Esthetics ; Humans ; Male ; Mouth Rehabilitation* ; Mouth* ; Occlusal Splints ; Prostheses and Implants* ; Seoul ; Tooth ; Tooth Attrition ; Tooth Eruption ; Tooth Wear ; Vertical Dimension