Postoperative Rehabilitation with a CAD/CAM-fabricated Occlusal Splint Following Plate Reconstruction after Hemimandibulectomy and Condylectomy: A Case Report.

Mandibular deviation (MD) is a common reconstruction sequela after segmental mandibulectomy. Although proper postoperative rehabilitation is critical for MD management and minimization, the information available is limited. This report describes postoperative rehabilitation with an occlusal splint fabricated using computer-aided design (CAD) and computer-aided manufacturing (CAM) (CAD/CAM-OS) and the results of a threedimensional occlusal analysis using an intraoral scanner after hemimandibulectomy and plate reconstruction. Despite the short follow-up, adherence to postoperative rehabilitation with CAD/CAM-OS for MD correction, even during radiotherapy, was demonstrated by the digital workflow and analysis results.

Effects of maxillofacial prosthetic treatment on oral health-related quality of life and masticatory ability of patients with head and neck tumors.

PURPOSE: Using multivariate analysis, this study investigated the effectiveness of maxillofacial prosthetic treatment in relation to oral health-related quality of life (OHR-QoL), masticatory ability (food intake status score and gum-jelly test score) and related factors in patients who had undergone surgery for head and neck tumors. METHODS: The study cohort comprised 112 patients who underwent surgical resection and prosthetic treatment among 224 patients with head and neck tumors seen at the Maxillofacial Prosthetics Clinic of Tohoku University Hospital in a 2-year period. Correlations between OHR-QoL, food intake status score, and gum-jelly test score (criterion variables), and age, sex, maxillary defect, tongue/soft tissue defect, reconstructive surgery, and chemoradiotherapy (explanatory variables) were investigated, and the data were examined statistically. RESULTS: Maxillary defect, tongue and soft palate tissue defect, and chemoradiotherapy were identified as factors that hindered the effectiveness of maxillofacial prosthetic treatment for improvement of the OHR-QoL, food intake status score, and gum-jelly test score. On the other hand, reconstructive surgery was a factor that facilitated the improvement of OHR-QoL and masticatory ability with maxillofacial prosthetic treatment. CONCLUSION: The factors identified to be related to the success or failure of maxillofacial prosthetic treatment suggest the importance of combining prosthetic intervention with surgical reconstruction.

A novel treatment based on powder jet deposition technique for dentin hypersensitivity: a randomized controlled trial.

BACKGROUND: This study aimed to evaluate the efficacy and safety of dentin hypersensitivity (DH) treatment using a newly developed device based on a powder jet deposition (PJD) technique that creates a hydroxyapatite (HAP) layer on the dentin surface, thereby alleviating the hypersensitivity. The effect of the PJD treatment was compared with that of conventional treatment using Teethmate Desensitizer (TMD; calcium-phosphate containing material with TTCP (Ca4(PO4)2O) and DCPA (CaHPO4)), which has been used clinically in Japan with well-confirmed effectiveness. MATERIALS AND METHODS: A randomized controlled trial was conducted including 35 patients who had symptoms of DH in two or more quadrants. Two test teeth were selected per patient (70 teeth in total) and randomly assigned to PJD or TMD treatment. The efficacy was evaluated using the improvement rate for air and scratch pain according to the scores obtained via visual analog scale 12 weeks after treatment. The safety assessment was performed focusing on gingival index (GI) and spontaneous pain. The t-test was used to analyze the non-inferiority of PJD treatment compared to TMD treatment. RESULTS: The improvement rate of air pain was 69.0% for PJD and 69.7% for TMD. The improvement rate of scratch pain was 80.8% for PJD and 81.7% for TMD. Non-inferiority with a margin of 10% was not observed for both air and scratch pain. No change was observed in GI from baseline and the improvement rate of spontaneous pain for PJD was higher than that for TMD. CONCLUSION: Non-inferiority of PJD to TMD treatment was not observed in this study; however, it was not statistically demonstrated, and the results were thus interpreted as inconclusive. PJD did improve the DH symptoms, as did TMD. PJD's therapeutic effect was most likely attributable to the deposition of a HAP layer on the tooth surface, which would alleviate hypersensitivity for at least 12 weeks without causing severe adverse events. TRIAL REGISTRATION: UMIN-CTR. ID: UMIN000025022. date: 02/12/2016.

Sensory neuromuscular electrical stimulation for dysphagia rehabilitation: A literature review.

BACKGROUND: Dysphagia is a common disorder following a cerebrovascular accident. It can cause detrimental effects on patient's quality of life and nutrition intake, especially in older adults. Neuromuscular electrical stimulation has been one of the management strategies for acceleration of the recovery. This review summarises the current evidence on sensory threshold stimulation of the procedure. METHOD: This review compiled data from the Internet database PubMed, Cochrane Library and Scopus using combination of MeSH thesaurus: 'Sensory threshold', 'electrical stimulation', 'neuromuscular stimulation', 'Deglutition', 'Dysphagia'. Eleven studies were intergraded into the review. RESULTS: Most of the studies show significant improvement to the outcomes of sensory neuromuscular electrical stimulation treatment. In many cases, the results of the treatment are comparable or superior to motor threshold stimulation and conventional therapy. However, the study design and parameters of the procedure varied greatly without conclusive standardised guidelines. CONCLUSION: The sensory neuromuscular electrical stimulation (SNMES) is a viable treatment option for treating oropharyngeal dysphagia. The most suggested application parameters are an intensity at sensory threshold, a frequency of 80 Hz, an impulse time of 700 µs, a combined total duration of 20 h of stimulation in a 2-week period, and placing the electrodes in the submental area of the neck. However, further research is necessary to construct a definitive guideline for clinicians.

Clinical Trial for Evaluating the Effectiveness and Safety of a New Dental Plaque Removal Device: Microscale Mist Unit.

This study evaluates the effectiveness and safety of a microscale mist unit (MSM-UNIT) that sprays high-speed fine water droplets to remove dental plaque adhering to the oral mucosa (tongue and palate) and tooth surface. Fifteen patients who had difficulty self-managing sufficient oral care were included in this study. Effectiveness was evaluated for at least five patients' tongues, palate mucosas, and tooth surfaces, and safety evaluation was conducted at all three sites for all patients. Effectiveness was evaluated using the rate of degree of dental plaque removal. Safety was evaluated using a numerical rating scale (NRS) for pain and symptoms of inflammation. An operator who performed treatment and an evaluator who evaluated effectiveness and safety were designated. In addition, an image judgment committee judged effectiveness. Although evaluation of the tongue varied between the evaluators and the image judgment committee, the rates of degree for all plaque removal increased in all regions. In addition, low pain NRS results and minimal symptoms of inflammation were observed and within an acceptable range. The MSM-UNIT can be used effectively and safely for removing oral plaque not only from teeth, but also from the oral mucosa.

Medical-Dental Collaboration and Interprofessional Training for Maxillofacial Diseases at Tohoku University Hospital.

The Tohoku University Hospital has been a clinical and research facility for all the related departments of Tohoku University. Medical-dental and interprofessional collaboration has resulted in special treatment teams, made up of members of departments such as the center for head and neck cancer, the center for dysphagia, and the cleft lip and palate center. Those treatment teams held conferences, case study meetings, reading sessions, and in-hospital seminars. The purpose of this study was to evaluate the outcomes of various medical-dental and the interprofessional collaboration at Tohoku University Hospital and training program to equip hospital dentists in higher medical institutions. The attainment targets are the acquisition of basic medical skills and knowledge under the guidance of supervising doctors. As a result, the hospital dentists could acquire their own specialized knowledge and skills certificated by each academic society. The smooth team treatment has been achieved, and the number of cases discussed by cancer boards and center for dysphagia has increased year by year due to the efficiency of their clinical pathways. On the dental care side as well, the wearing rates of maxillofacial prosthetic devices such as maxillofacial prostheses and palatal augmentation prostheses (PAP) have improved, which have contributed to improving patient's stomatognathic function. Tohoku University Hospital has been practicing collaboration between medical and dental professionals and it has produced mutual benefits. Our interprofessional training system based on the medical-dental collaboration could develop professionals who have acquired cross-disciplinary knowledge and skills from experienced doctors.

Changes in tongue pressure and dysphagia at oral cancer patients by palatal augmentation prosthesis.

BACKGROUND: The palatal augmentation prosthesis (PAP) is an intraoral prosthesis used in the treatment of dysphagia. AIM: The objective of the study is to examine the effect of PAP using tongue pressure and the Videofluoroscopic Dysphagia Scale (VDS) to understand the precise mechanism for improvement in swallowing function with PAP for oral cancer at retrospective survey. METHODS AND RESULTS: Fifteen patients were provided PAPs. Tongue pressure and VDS were evaluated with and without PAP. After intervention with PAP, tongue pressure significantly increased as compared to when without PAP (p < .05). The total mean VDS score with PAP was found to have significantly improved (p < .05). The mean VDS score of the oral phase also significantly improved with the PAP compared to without the PAP group (p < .05). Significant differences (p < .01) were found in each category, such as tongue to palate contact and pyriform sinus residue. CONCLUSION: PAP can improve tongue pressure, tongue to palate contact, and pyriform sinus residue.

Bifacial biological effects of ethanol: acetaldehyde production by oral Streptococcus species and the antibacterial effects of ethanol against these bacteria.

Background:Many previous studies have focused on the acetaldehyde produced from ethanol by oral bacteria as a risk factor for oral cancer. Most of these studies involved low ethanol concentrations (ca. 10 mM), but oral bacteria are exposed to a wide range of ethanol concentrations (100-10,000 mM) when alcoholic beverages are consumed. In contrast, ethanol is widely used at high concentrations (> 5,000 mM) as an antiseptic/disinfectant, suggesting that ethanol has bifacial biological effects; i.e. it acts as both a metabolic substrate for bacterial acetaldehyde production and an antimicrobial agent. Materials and methods:We examined the acetaldehyde production from ethanol by oral streptococci and the effects of ethanol exposure on the growth and viability of these bacteria at a wide range of ethanol concentrations (10-10,000 mM). Results:Acetaldehyde production was the highest at an ethanol concentration of 2,000 mM (2.1-48-fold higher than that seen at an ethanol concentration of 10 mM). Bacterial growth was inhibited by > 1,000 mM of ethanol, and the bacteria did not seem viable in the presence of > 5,000 mM of ethanol, although they still produced acetaldehyde. Conclusion:Ethanol has bifacial biological effects, and the concentration ranges of these effects overlap.

Effectiveness and safety of a new dental plaque removal device utilizing micro mist spray for removing oral biofilm in vitro.

BACKGROUND: Removal of oral biofilm from the oral mucosa is essential for preventing risk of respiratory and gastrointestinal infection in elderly people. Currently, no device is available which can remove oral biofilm from oral mucosa effectively and safely. Therefore, the effectiveness and safety of the Micro Scale Mist UNIT (MSM-UNIT), a newly developed dental plaque removal device utilizing high speed sprays of fine water droplets, were evaluated for biofilm removal, including the rate and surface roughness for simulated tooth surface and mucous membrane. METHODS: Simulated tooth and oral mucosa coated with an artificial biofilm of Streptococcus mutans were used for evaluation of effectiveness, with uncoated substrates as the controls. The MSM-UNIT and a conventional air ablation device were operated under recommended instructions. The effectiveness was evaluated from the rate of removal of the biofilm, and the safety was evaluated from the damage observed by scanning electron microscope and surface roughness. RESULTS: The biofilm removal rate of the MSM-UNIT was significantly higher than that of AIRFLOW. Little damage was observed in the area treated by the MSM-UNIT. The surface roughness of the MSM-UNIT treated area on simulated tooth surface and oral mucosa showed no significant difference to the control area. In contrast, cracks and powder were observed in the area treated by AIRFLOW. In particular, the surface roughness of the AIRFLOW treated area for Toughsilon was significantly larger than that of the control. CONCLUSIONS: The MSM-UNIT could be used safely and effectively for removing biofilm not only on simulated tooth surfaces but also simulated mucous membrane. The MSM-UNIT has no harmful effect on teeth or oral mucosa, and may be used for comprehensive oral care for patients during nursing care and the perioperative period.

Metabolic property of acetaldehyde production from ethanol and glucose by oral Streptococcus and Neisseria.

Acetaldehyde is known to be carcinogenic and produced by oral bacteria. Thus, bacterial acetaldehyde production might contribute to oral cancer. Therefore, we examined bacterial acetaldehyde production from ethanol and glucose under various conditions mimicking the oral cavity and clarified the metabolic pathways responsible for bacterial acetaldehyde production. Streptococcus mitis, S. salivarius, S. mutans, Neisseria mucosa and N. sicca were used. The bacterial metabolism was conducted at pH 5.0-8.0 under aerobic and anaerobic conditions. The production of acetaldehyde and organic acids was measured with gas chromatography and HPLC, respectively. Bacterial enzymes were also assessed. All of the bacteria except for S. mutans exhibited their greatest acetaldehyde production from ethanol at neutral to alkaline pH under aerobic conditions. S. mutans demonstrated the greatest acetaldehyde from glucose under anaerobic conditions, although the level was much lower than that from ethanol. Alcohol dehydrogenase and NADH oxidase were detected in all of the bacteria. This study revealed that oral indigenous bacteria, Streptococcus and Neisseria can produce acetaldehyde, and that such acetaldehyde production is affected by environmental conditions. It was suggested that alcohol dehydrogenase and NADH oxidase are involved in ethanol-derived acetaldehyde production and that the branched-pathway from pyruvate is involved in glucose-derived acetaldehyde production.