Does maintaining the number of present and functional teeth benefit the longevity of life in older people requiring nursing care?: A prospective cohort study.

PURPOSE: This prospective cohort study examined the effects of the number of present and functional teeth on mortality among older Japanese adults requiring nursing care in an environment of comprehensive oral hygiene and nutritional management. METHODS: The study included 174 older adults (mean age: 84.4 ± 8.3 years; male/female: 49/125) in need of support or long-term care, who resided in either a local specialized healthcare facility or their own homes, and received daily oral hygiene and nutritional support at facilities in Okayama, Japan. The initial clinical oral examination along with assessment of general physical condition and nursing environment of the participants were performed in July 2013 and followed up for one year. RESULTS: All-cause mortality occurred in 28 (mean age: 88.7 ±13.4 years; male/female: 6 /22) individuals during the follow-up period. Cox proportional hazard analysis indicated that older age, low performance in activities of daily living (Barthel Index <40), and underweight status (body mass index <18.5) were significant risk factors for mortality. The number of present and functional teeth were not found to be significant risk factors for mortality. CONCLUSIONS: During the one-year follow-up period, the number of present and functional teeth did not have a significant impact on mortality among older Japanese adults requiring nursing care in a well-managed environment of oral hygiene and nutritional status.

Effect of soft denture liners on complete denture treatments: A systematic review.

PURPOSE: This systematic review examined the effectiveness of soft denture relining (SDR) materials. STUDY SELECTION: A comprehensive search of MEDLINE, Cochrane Library, and ICHUSHI was conducted up to July 26, 2020. Target outcomes were patient satisfaction, oral health-related quality of life (OHRQOL), masticatory ability (MA), denture functional duration, residual ridge resorption (RRR), and microbial contamination. An organization specializing in literature searches performed the reference searches, and two reviewers independently selected the literature sources, extracted the data, and assessed the risk of bias. The reviewers resolved any disagreements concerning the assortment of literature sources through discussion. SDR included acrylic- and silicone-based materials, which were evaluated separately. RESULTS: Reviewers selected 7, 5, 11, 1, 4, and 6 studies to assess patient satisfaction, OHRQOL, MA, functional duration, RRR, and microbial contamination, respectively. The results confirmed that SDR improved patient satisfaction, OHRQOL, MA, and RRR. However, the functional duration of SDR material is shorter than that of hard denture relining (HDR) or acrylic resin material. Furthermore, SDR material is more susceptible to microbial contamination in the long term. The risk of bias for the included studies tended to be high because of specific issues (difficulty in blinding SDR versus HDR). CONCLUSIONS: For patients who wear complete dentures, SDR often provides beneficial outcomes such as pain reduction and recovery from MA. However, caution should be exercised regarding their use owing to insufficient functional duration and the possibility of microbial contamination during long-term use.

Managements of sleep bruxism in adult: A systematic review.

This systematic review aimed to update the management of sleep bruxism (SB) in adults, as diagnosed using polysomnography (PSG) and/or electromyography (EMG). Management methods covered were oral appliance therapy (OAT) with stabilization splints, cognitive-behavioral therapy (CBT), biofeedback therapy (BFT), and pharmacological therapy. A comprehensive search was conducted on MEDLINE, Cochrane Library, and Web of Science up to October 1st, 2021. Reference list searches and hand searches were also performed by an external organization. Two reviewers for each therapy independently performed article selection, data extraction, and risk of bias assessment. The reviewers resolved any disagreements concerning the assortment of the articles by discussion. Finally, 11, 3, 14, and 22 articles were selected for each therapy. The results suggested that OAT tended to reduce the number of SB events, although there was no significant difference compared to other types of splints, that the potential benefits of CBT were not well supported, and that BFT, rabeprazole, clonazepam, clonidine, and botulinum toxin type A injection showed significant reductions in specific SB parameters, although several side effects were reported. It can be concluded that more methodologically rigorous randomized large-sample long-term follow-up clinical trials are needed to clarify the efficacy and safety of management for SB.

Six-year follow-up assessment of prosthesis survival and oral health-related quality of life in individuals with partial edentulism treated with three types of prosthodontic rehabilitation.

Purpose The purpose of the study was to compare the long-term performance of three prostheses for partial edentulism: implant-supported, fixed denture (IFD), fixed partial denture (FPD), and removable partial denture (RPD), in terms of prosthesis survival and oral health-related quality of life (OHRQoL).Methods The 138 patients in our previous study (Kimura et al., 2012) received one of the three prosthetic treatments and answered a validated OHRQoL questionnaire before and immediately after treatment. In the present study, the patients were followed up six years after treatment using medical records and OHRQoL examinations to evaluate prosthesis survival and change in OHRQoL. The cumulative survival rates were calculated using the Kaplan-Meier analysis. The Steel-Dwass test was used to compare the median OHRQoL scores at the three time points.Results For the 105 patients (66.8 ± 10.8 years, IFD/FPD/RPD: 58/27/20 patients) who successfully completed the follow-up assessments, the six-year estimated cumulative survival rates of the IFDs, FPDs, and RPDs were 94.7%, 77.4%, and 33.3%, respectively. The log-rank tests indicated that the survival curves were significantly different (IFDs vs. FPDs: p = 0.01; RPDs vs. IFDs, FPDs: p < 0.01). The median OHRQoL scores of the IFD group immediately after treatment and six years after treatment were significantly higher than those observed before treatment (p < 0.01). There was no significant difference in the median OHRQoL scores among the three time points in the RPD or FPD groups.Conclusions IFDs showed significantly longer survival rates than FPDs and RPDs in partially edentulous patients. Only in the IFD patients was the OHRQoL level six years after treatment significantly higher than that before treatment.

Vibratory splint therapy for decreasing sleep clenching: A pilot study.

OBJECTIVE: To estimate the effect of a vibratory splint (VibS) in reducing sleep clenching (SC) and TMD pain. METHODS: Target sample was consecutive 19 TMD patients attending the Orofacial Pain Clinic at FFO-FOUSP. Patients used the VibS or acrylic occlusal splint (OS) as control for 14 days. Outcome variables were SC frequency and pain, assessed by a portable electromyography detector-analyzer (BiteStrip™) and 100 mm VAS, respectively. Statistical analyses were performed with two-way repeated measures ANOVA, and analysis of covariance (ANCOVA). RESULTS: VibS promoted a marked decrease, whereas acrylic OS increased SC frequency after two weeks of use. Due to a significant difference in initial VAS levels between VibS and control group, the effect of the two splints on TMD pain could not be clearly estimated. CONCLUSION: The results suggested that VibS can potentially be used to reduce SC frequency, although further studies with larger sample size are necessary to confirm these findings.

Association of masticatory muscle activity with sleep arousal and other concomitant movements during sleep.

OBJECTIVE: This study aims to verify the associations among sleep bruxism (SB), sleep arousal (SA) and concurrent body movements. MATERIAL AND METHODS: Subjects underwent a standard overnight polysomnography test and audio-video recordings. Sleep quality was evaluated according to the Rechtschaffen and Kales criteria, while SA was determined as per the American Sleep Disorders Association criteria. Analyses were performed by an external institution after masking of the subjects' information. SB was assessed based on the presence/absence of rhythmic masticatory muscle activity (RMMA) episodes, which were identified by using electromyography of the masseter muscle. The observed simultaneous movements included lower leg movement (LLM), swallowing, face scratching, head movement, body movement, eye blinking, coughing, licking, sighing, body scratching, lip sucking, somniloquy and yawning. The LLM was determined visually, as well as through an increase in the tibialis electromyogram signal. Other movements were visually assessed using audio-video recordings. The incidences of all the simultaneous movements were compared between RMMA with intercurrent SA (SAwRMMA; RMMA episode derived from a masseter electromyogram showing more than 10% of maximum voluntary contraction) and SA without RMMA (SAw/oRMMA). RESULTS: Fourteen subjects were included in this study (females/males: 4/10, mean age: 31.5 ± 5.7 years). Among these, LLM, swallowing, body movement, licking, body scratching and lip sucking were frequently observed in SAwRMMA episodes than in SAw/oRMMA episodes, significantly. However, the non-specific simultaneous movements were higher observed in SAw/oRMMA episodes than that in SAwRMMA. CONCLUSION: Our results suggest that SB is concurrently activated with LLM in relation to arousal.

Loss of oral self-care ability results in a higher risk of pneumonia in older inpatients: A prospective cohort study in a Japanese rural hospital.

OBJECTIVES: To identify significant risk factors associated with incidence of mortality and pneumonia in whole-community-based older inpatients resident in Japanese rural region. METHODS: Patients older than 65 years admitted between 1 April and 15 April 2010 to a core hospital located in a rural region were exhaustively recruited, and incidence of mortality and pneumonia during the 32-month follow-up period were evaluated. Independent variables at baseline measurement included age, gender, body mass index, Charlson comorbidity index, functional dependency, oral self-care ability index, number of remaining teeth, hyposalivation and nutritional status. Dependent variables were incidence of mortality and pneumonia. Survival and non-pneumonia curves were drawn using Kaplan-Meier analysis. Cox proportional hazards analysis was performed to identify the risk factors related to incidence of mortality and pneumonia. RESULTS: The survival rate of 46 patients (male/female: 11/35; mean age: 83.8 ± 6.8 years) was 52.1%, and the incidence of pneumonia was 60.9%. Malnutrition and gender (male) were identified as significant risk factors for mortality (odds ratio [OR]: 8.18 and 4.90; 95% confidence interval [CI]: 1.77-37.3 and 1.50-16.0; P < 0.01 and <0.01, respectively). Loss of oral self-care ability and gender (male) were identified as significant risk factors for incidence of pneumonia (OR: 8.97 and 4.58; 95% CI: 1.70-47.4 and 1.50-14.0; P = 0.01 and <0.01, respectively). CONCLUSIONS: Malnutrition and loss of oral self-care ability were significant risk factors for incidence of mortality and pneumonia, respectively. In response, supplying nutrition with appropriate diet and personalised oral care might contribute to reduction in mortality and prevention of pneumonia.

Reliability and validity of the patient disability-oriented diagnostic nomenclature system for prosthetic dentistry.

PURPOSE: The Japan Prosthodontic Society (JPS) has proposed a new diagnostic nomenclature system (DNS), based on pathogenesis and etiology, to facilitate and improve prosthodontic treatment. This system specifies patient disability and the causative factor (i.e. "B (disability) caused by A (causative factor)"). The purpose of this study was to examine the reliability and validity of this DNS. STUDY SELECTION: The JPS Clinical Guideline Committee assessed mock patient charts and formulated disease names using the new DNS. Fifty validators, comprising prosthodontic specialists and dental residents, made diagnoses using the same patient charts. Reliability was evaluated as the consistency of the disease names among the validators, and validity was evaluated using the concordance rate of the disease names with the reference disease names. RESULTS: Krippendorff's α was 0.378 among all validators, 0.370 among prosthodontic specialists, and 0.401 among dental hospital residents. Krippendorff's α for 10 validators (3 specialists and 7 residents) with higher concordance rates was 0.524. Two validators (1 specialist and 1 resident) with the highest concordance rates had a Krippendorff's α of 0.648. Common disease names had higher concordance rates, while uncommon disease names showed lower concordance rates. These rates did not show correlation with clinical experience of the validator or time taken to devise the disease name. CONCLUSIONS: High reliability was not found among all validators; however, validators with higher concordance rates showed better reliability. Furthermore, common disease names had higher concordance rates. These findings indicate that the new DNS for prosthodontic dentistry exhibits clinically acceptable reliability and validity.

Sleep bruxism frequency and platelet serotonin transporter activities in young adult subjects.

PURPOSE: To evaluate correlations between serotonin transporter (SERT) uptake ability in human peripheral platelets and sleep bruxism (SB) frequency. METHODS: Subjects were consecutively recruited from sixth-year students at Okayama University Dental School. Subjects were excluded if they (1) were receiving orthodontic treatment, (2) had a dermatological disease, (3) had taken an antidepressant within 6 months, or (4) had used an oral appliance within 6 months. SB frequency was determined as the summary score of three consecutive night assessments using a self-contained electromyography detector/analyzer in their home. Fasting peripheral venous blood samples were collected in the morning following the final SB assessment. SERT amount and platelet number were quantified via an ELISA assay and flow cytometry, respectively. Functional SERT characterization, 5-hydroxytryptamine (5-HT) uptake, maximum velocity (V max), and an affinity constant (K m ) were assessed with a [(3)H] 5-HT uptake assay. The correlations between these variables and SB level were evaluated. RESULTS: Among 50 eligible subjects (26 males, mean age 25.4 ± 2.41 years), 7 were excluded because of venipuncture failure, smoking, and alcohol intake during the experimental period. A small but significant negative correlation between SB level and [(3)H] 5-HT uptake was observed (Spearman's correlation R (2) = 0.063, p = 0.04). However, there were no significant correlations between SB level and total platelet amount, SERT, V max, and K m values (p = 0.08, 0.12, 0.71, and 0.68, respectively). CONCLUSIONS: Platelet serotonin uptake is significantly associated with SB frequency, yet only explains a small amount of SB variability.

A risk factor analysis of accumulated postoperative pain and swelling sensation after dental implant surgery using a cellular phone-based real-time assessment.

PURPOSE: The purpose of this study was to identify the related risk factors of dental implant accumulated postoperative pain and swelling by cellular phone-based assessment. METHODS: Subjects were a consecutive series of patients who received oral implant surgery at Okayama University Hospital. Cellular phone-based questionnaire was sent at pre-set schedule to each subject every 2h on the day of surgery, and every 24h from the 2nd to 7th day post-surgery. Subjects replied in real-time the pain and swelling levels at the operated sites by an 11- and 4-grade rating-scale questionnaire. Overall intensity of individual pain and swelling was calculated by means of area under curve that drew by their time-dependent changes. Predictor variables were age, gender, presence of diabetes mellitus and/or hypertension (DM/HT), history of implant surgery, number of inserted implants, flap operation, surgical duration, pre-surgery anxiety, osteoplasty, bone quality, premedication, dosage of prescribed analgesics and local anesthesia and accumulated postoperative pain/swelling. Compliance rate and risk factors correlated with accumulated postoperative pain and swelling were calculated by multiple regression analysis. RESULTS: Final subjects were 18 females and 7 male (mean age: 59.3±7.32 yrs). Significant factors correlated with accumulated postoperative pain were DM/HT, surgical duration, premedication, bone quality, pre-surgery anxiety and postoperative swelling (R(2)=0.769, p=0.001, 0.013, 0.032, 0.007, 0.035 and 0.007, respectively). Meanwhile, significant factors associated with postoperative swelling were postoperative pain, DM/HT and bone quality (R(2)=0.365, p=0.002, 0.004, 0.008, respectively). CONCLUSION: These results suggested DM/HT and bone quality are correlated to overall intensity of postoperative pain and swelling.

Comparison of platelet serotonin transporter activity in subjects with severe sleep bruxism and control.

PURPOSE: The aim of this study was to evaluate the correlation between sleep bruxism (SB) frequency and serotonin transporter (SERT)-driven serotonin (5-HT)-uptake in platelets. METHODS: Subjects were dental trainee residents and faculty members of Okayama University Hospital who were aware of having severe or no SB. SB frequency was assessed for 3-consecutive nights by a self-contained electromyographic detector/analyzer, which indicated individual SB levels as one of four grades (score 0, 1, 2 and 3). Subjects were classified as normal control (NC) when SB scores indicated only 0 or 1 during the 3 nights, or as severe SB for scores 2 or 3. Those subjects whose scores fluctuated from 0 to 3 during the 3 nights were omitted from further analysis. Fasting peripheral venous blood samples were collected in the morning following the final SB assessment. Amounts of SERTs proteins collected from peripheral platelets were quantified using ELISA, and SERTs transport activity was assessed by uptake assay using [3H]-5-HT. RESULTS: Thirteen severe SB subjects and 7 NC subjects were eligible. Gender distribution, mean age, 5-HT concentration and total amounts of SERT protein in platelets showed no significant differences between NC and severe SB (p=0.85: Chi-squared test; p=0.64, 0.26, 0.46: t-test). However, [3H]-5-HT uptake by platelets was significantly greater in NC compared to severe SB subjects (12.79±1.97, 8.27±1.91 fmol/10(5) platelets/min, p<0.001, t-test). CONCLUSION: The results of this pilot study suggest a possible correlation between peripheral platelet serotonin transporter uptake ability and SB severity.

Retrospective investigation of the remaining teeth status of patients with implant-supported fixed partial dentures in unilateral free-end edentulism.

PURPOSE: This study aimed to compare the various complication-free rates and survival rates of remaining teeth among implant-supported fixed dentures (IFDs), removable partial dentures (RPDs) and no-restoration (NR) patients with unilateral free-end edentulism. MATERIAL AND METHODS: The study subjects were selected among those who received prosthodontic treatment at Okayama University Dental Hospital for their unilateral free-end edentulism (2 or 3 missing teeth). Thirty-three patients were included in the IFD group, 41 matched patients in the RPD group, and 10 patients who received RPDs but refused their use were regarded as NR group. The remaining dentition was classified into five subcategories in relation to the missing portion: adjacent teeth to the missing portion (AD), contralateral posterior dentition in the same jaw (CS) and in the opposite jaw (CO), ipsilateral opposing posterior dentition (IO), and anterior dentition (AN). Complications were defined as tooth extraction, periodontal lesions, periapical lesions or loss of retention of the prosthesis and were assessed by one examiner based on the hospital chart records. RESULTS: The cumulative complication-free rates in the remaining teeth were significantly different among each of the three groups (p<0.01), with a significantly lower incidence rate in the IFD group. Regarding the cumulative survival rate of the remaining teeth, there was a significant difference only between IFD and NR group (p=0.01), especially in the CO region (p=0.04). CONCLUSIONS: Stable posterior occlusal support obtained with IFD treatment for unilateral free-end edentulism may reduce the incidence of complications in the remaining teeth, by decreasing the adverse mechanical stress.

Retrospective comparative ten-year study of cumulative survival rates of remaining teeth in large edentulism treated with implant-supported fixed partial dentures or removable partial dentures.

PURPOSE: This study aimed to compare the survival rates of remaining teeth between implant-supported fixed dentures (IFDs) and removable partial dentures (RPDs) in patients with large edentulous cases. The second goal was to assess the risk factors for remaining tooth loss. MATERIALS AND METHODS: The study subjects were selected among those who received prosthodontic treatment at Okayama University Dental Hospital for their edentulous space exceeding at least four continuous missing teeth. Twenty-one patients were included in the IFD group and 82 patients were included in the RPD group. Survival rates of remaining teeth were calculated in three subcategories: (1) whole remaining teeth, (2) adjacent teeth to intended edentulous space, and (3) opposing teeth to intended edentulous space. RESULTS: The ten-year cumulative survival rate of the whole remaining teeth was significantly higher in the IFD group (40.0%) than in the RPD group (24.4%). On the other hand, there was no significant difference between two groups in the survival rate of teeth adjacent or opposing to intended edentulous space. A Cox proportional hazard analysis revealed that RPD restoration and gender (male) were the significant risk factors for remaining tooth loss (whole remaining teeth). CONCLUSIONS: These results suggest that IFD treatment can reduce the incidence of remaining tooth loss in large edentulous cases.

A retrospective comparative 8-year study of cumulative complications in teeth adjacent to both natural and implant-supported fixed partial dentures.

PURPOSE: To compare the complication rate of natural teeth adjacent to implant supported dentures (IFDs) with that of teeth serving as abutments for fixed partial dentures (FPDs). The second goal was to assess the risk factors for complications in teeth adjacent to bounded edentulous spaces. MATERIALS AND METHODS: The study subjects were selected from patients who received prosthodontic treatment for their bounded edentulous space not exceeding two missing teeth between February 1990 and March 2007. Sixty-one patients were included in the IFD group and 66 patients were included in the FPD group. Tooth complications were defined as tooth extraction, periodontal lesion, periapical lesion, and loss of prosthesis and were assessed by one examiner based on dental records. RESULTS: The 8-year cumulative complication rate for the IFD group (7.9%) was significantly lower than for the FPD group (40.7%). Additionally, the 8-year cumulative complication rate of vital teeth (6%) was significantly lower than that of nonvital teeth (45.9%). A cox proportional hazard analysis revealed that nonvitality of dental pulp was a significant risk factor for tooth complications, whereas treatment modality was not. CONCLUSIONS: Teeth adjacent to IFD-treated edentulous spaces presented fewer complications than natural teeth serving as abutments for FPDs. Conservation of teeth adjacent to edentulous spaces as vital teeth was the key finding to limit further tooth loss.

A problem-based learning tutorial for dental students regarding elderly residents in a nursing home in Japan.

This educational trial was an eight-day problem-based learning (PBL) course for fourth-year predoctoral students at Okayama University's dental school who interviewed elderly residents living in a nursing home. The purpose of this PBL course was to introduce geriatric dentistry to the students by allowing them, independently, to discover the clinical problems of elderly patients as well as the solutions. The sixty-five students were divided into nine small groups and received patient information (age, gender, degree of care needed, medical history, food type, medications, and oral condition) in datasheets before visiting the nursing home. Each group of students directly interviewed one patient and the caregivers and identified the patient's medical, psychological, and social problems. After the interview, the students participated in a PBL tutorial to delineate a management approach for the patient's problems. To measure the efficacy of this program, the students completed a questionnaire before and after the course regarding their level of understanding of and attitudes toward geriatric dentistry, clinical research, and self-study. The results showed that student's perceptions of their knowledge about and attitudes toward oral health care for the elderly significantly increased after the PBL course, which suggests that such tutorials should be an option for dental curricula.

Multiple sleep bruxism data collected using a self-contained EMG detector/analyzer system in asymptomatic healthy subjects.

PURPOSE: Small, self-contained electromyographic (EMG) detector/analyzer (D/A) devices have become available for the detection of jaw muscle activity events above threshold. These devices claim to be less intrusive to the subjects sleep so it is less prone to induce disturbed sleep. The objective of this study was to evaluate for night-to-night variability and examine for a systematic alteration on the first night in EMG levels. METHODS: Ten asymptomatic healthy volunteers (mean age, 26.8 ± 3.78) were recorded for six sequential nights in their home environment using EMG D/A system. The device yields a nightly EMG level above threshold score on a 0-4 level. Because the data are categorical and nonparametric, the data of the ten subjects across six nights were submitted to a Friedman repeated measures ANOVA. The significant level was set as alpha equal to 0.05. RESULTS: The median and mode values of the subjects were tabulated and analyzed and we did not find a significant difference in EMG D/A level across the six nights (p = 0.287, Kendall's coefficient of concordance = 0.124, Friedman two-way repeated measures ANOVA). The data did show clear and substantial night-to-night variability. CONCLUSION: Substantial night-to-night variability in masseter EMG activity levels was clearly observed in our subjects. There was no evidence of a suppressed or elevated first-night effect-like variability on masseter muscle EMG level seen in these subjects using a small portable self-contained EMG detector/analyzer. These data suggest that recordings should be at least 5-6-nights duration to establish a reasonable measure of an individual's average nightly masseter EMG level.

Test-retest reliability of MRI-based disk position diagnosis of the temporomandibular joint.

This study evaluated the test-retest reliability for determining the temporomandibular joint (TMJ) disk position, diagnosed using magnetic resonance imaging (MRI). These assessments were done as a base-line measurement for a prospective cohort study, which examines the risk factors for precipitation and progression of temporomandibular disorders. Fifteen subjects (mean age, 24.2 ± 0.94 years; male/female = 8/7) were recruited from the students of Okayama University Dental School. Sagittal MR TMJ images were taken with a 1.5-T MR scanner (Magneton Vision, Siemens) in close and maximal open positions twice at about 1-week (6-11 days) interval. The images were displayed using 200% magnification on a computer screen with a commercially available image software package (OSIRIS, UIN/HCUG). Three calibrated examiners diagnosed the disk positions using the standardized criteria. The disk position of each joint was classified as normal, anterior disk displacement with or without reduction, and others. The first and second disk position diagnoses were compared, and the test-retest reliability level was calculated using the kappa index. The second disk position diagnosis was consistent with the first in 27 out of 30 joints. The calculated kappa value representing the test-retest reliability level between the first and second disk position diagnosis was 0.812. These results indicated that the test-retest reliability of MRI-based diagnosis of TMJ disk positions at about 1-week interval was substantially high, even though they were not completely consistent.

A 15-year clinical comparative study of the cumulative survival rate of cast metal core and resin core restorations luted with adhesive resin cement.

PURPOSE: The aim of this study was to compare the core survival rates (CSRs) of cast metal versus resin core restorations luted with adhesive resin cement, as well as to determine the risk factors for core failure. MATERIALS AND METHODS: Nine hundred ninety-one patients (2,124 cores) who received either cast metal or resin cores luted with adhesive resin cement at the Fixed Prosthodontic Clinic of Okayama University Dental Hospital between April 1988 and December 1991 and whose structured clinical core record was filled appropriately comprised the study subjects. The clinical core record included information regarding patient age, sex, core restoration type, tooth location, tooth type, remaining coronal dentin, and root canal form. CSRs, as well as causes for failure, were analyzed 15 years postinsertion. Since 381 patients lacked data regarding predictors for core failure, a subsample of 610 patients (1,053 cores) was used for the subsequent risk factor analysis. RESULTS: The cumulative CSR of resin cores (78.7%) was significantly higher than that of cast metal cores (55.4%; log-rank test, P < .0001). The Cox proportional hazards test revealed that sex (male, P < .0001), absence of remaining coronal dentin (P = .0057), core restoration type (cast metal, P = .0186), and higher age at core insertion (P = .0380) were significant predictors for core failure. The incidence of complications, such as core loosening (P = .0016) and tooth extraction (P < .0001), was significantly higher in cast metal cores. CONCLUSIONS: Cast metal cores were associated with a significantly lower CSR than resin cores, and significant risk factors for core failure were sex (male), absence of remaining coronal dentin, core restoration type (cast metal), and higher age at core insertion.

The relationship between temporomandibular joint pathosis and muscle tenderness in the orofacial and neck/shoulder region.

OBJECTIVE: The objective of this study was to investigate the association between TMJ pain/disk pathosis and the muscle tenderness pattern in the orofacial and neck/shoulder region. STUDY DESIGN: One hundred seventy-one TMD patients were divided into 4 groups, including group 1: patients with painful unilateral TMJ disk displacement (DD); group 2: patients with painless unilateral TMJ DD; group 3: patients with painless bilateral TMJ DD; and group 4: patients with a bilateral normal TMJ disk position (n = 41). Each subject underwent muscle palpation and the side-by-side number of muscle tenderness points was combined as the number of muscle tenderness points on each side. Within each group, DD with and without reduction subjects were separated into subgroups and then were analyzed. RESULTS: In group 1, the median muscle tenderness points on the side with painful TMJ DD without reduction was significantly higher than on the normal side (P = .019), whereas the palpation scores for painless DD patients showed no significant difference between the DD and normal sides. CONCLUSIONS: These results indicated painful disk displacement to possibly be correlated with ipsilateral muscle tenderness.

[Case report of an osteoarthritic temporomandibular joint patient whose posterior open bite was successfully restored by occlusal bonding method].

PATIENT: The patient was a 50-year-old woman who complained of left temporomandibular joint pain during mastication and wide mouth opening. The diagnosis of this patient was bilateral osteoarthritis in temporomandibular joint; therefore maxillary full-arch stabilization appliance (SA) was delivered. In response, the TMD signs and symptoms were alleviated. However she subsequently complained of dysfunction of mastication due to anterior and posterior open bite. Sometime thereafter, after applying SA and provisional adhesion onlay, occlusal reconstruction was performed by means of porcelain direct-bonding onlay. DISCUSSION: After 6 years follow-up, there were no failure finding on the porcelain direct-bonding onlay, no occlusal alteration, and no complaint of TMD signs and symptoms. CONCLUSION: This direct-bonding adhesion prosthetic approach contributed not only to prevent aggravation of osteoarthritis but also to elevate QOL of this patient.