Polypharmacy is a problem in the clinical practice of elderly medical care. Symptoms caused by polypharmacy are diverse, including falls and deterioration of cognitive function, as well as dysphagia. Textbooks state that neurodegenerative diseases such as stroke and Parkinson’s disease are common causes of swallowing disorder, but there are unexpectedly many drug-induced swallowing disorders in the field of elderly medical care.
Typical medicines that cause drug-induced swallowing disorders are sleep-related drugs such as sleep medication, anxiolytics, and antipsychotic drugs. Dentists working in the field of dental sleep medicine are in a good position to treat such disorders because they have knowledge of which sleep-related drugs are likely to cause swallowing disorders, and which drugs do not affect swallowing disorders while improving sleep disorders.
Dentists specializing in sleeping dentistry are important for managing drug-induced swallowing disorders in cooperation with prescription physicians. Dental sleep medicine may have an important role to play in treating polypharmacy.

View full abstract

In conventional medical fields in Japan, researchers have believed that it is sufficient to publish papers about their research, and there has been a tendency whereby researchers should write papers if they have time to apply for patents. However, the environment surrounding researchers is changing and it is becoming difficult even for those researchers with outstanding results to implement them in practice simply by publishing a paper on them. A tie-up with a corporation is important in order to put the results of research into practice, and it is highly effective and appealing to corporations for researchers to have patents granted for their research results. It is often said that obtaining a patent can provide a feeling of security for corporations, which successfully leads to smooth tie-ups with those corporations in order to put the results of research into practice. However, the fact remains that many researchers still think that patents are irrelevant in medical fields and that it is sufficient to present their groundbreaking results to the public through papers alone. We hope this article will help those researchers to understand that a patent is a highly effective tool that can be used to “visualize” their research results.

View full abstract

The number of medical malpractice cases in Japan increased through 2004, then turned to a declining trend, and has been slightly increasing in recent years. When including partial wins, around 20％ of these cases are won by patients.
In dental treatment, negligence is judged when the treatment does not reach the “medical standard of care”. The “medical standard of care” is not a nationwide uniform standard, but is determined in light of “various circumstances” such as the specialty of the doctor （dentist）, the character of the medical institution, and the characteristics of the local healthcare environment.
In civil lawsuits, clinical practice guidelines can be used as evidence without limitation. There is a report that negligence was judged in 2.2％ of the cases that adhered to clinical practice guidelines, and in 47％ of the cases that did not, indicating the significance of clinical practice guidelines in litigations.
Doctors （dentists） need to inform the patient of not only the recommended therapy, but also what alternatives there are, and the possible merits and demerits when followed without treatment. Dental records are important evidence in court and must be fully described.
Doctors and dentists have a duty called “Ousho Gimu.” Under this duty, doctors and dentists should not refuse a patient’s request for medical treatment without reasonable cause, though in recent years new notices have been promulgated by the Ministry of Health, Labour and Welfare.
Looking back at the history of delirium onset by anesthetics, there were many cases in which dentists were involved, further indicating the importance of providing full information and sufficient patient management.

View full abstract

Objectives : Polysomnography （PSG） is the standard method used to determine the efficacy of oral appliance （OA） treatment for obstructive sleep apnea （OSA） in our department. Pulse oximetry is also performed prior to PSG to evaluate OA efficacy, though the results can be inconsistent. Hence, a comparison study was conducted to determine the validity of pulse oximetry in evaluating OSA severity compared to PSG.
Methods : Among the 251 OSA cases who first visited the department between 2011 and 2015, 136 patients were evaluated using PSG and pulse oximetry after undergoing OA treatment. Since pulse oximetry is generally performed multiple times, the maximum, minimum, and average of 2％ oxygen desaturation index （ODI）, 3％ ODI, and 4％ ODI were compared to the apnea hypopnea index （AHI） scores from PSG data.
Results : The 3％ ODI_Max correlated most strongly with AHI （r＝0.500, p＜0.001, y＝0.602x＋6.783 （y：AHI, x：ODI））. In terms of severity, 2％ ODI_Max correlated most strongly with mild cases of OSA （r＝0.501, p＜0.001）, while 3％ ODI_Max correlated with moderate cases. In severe cases, no significant correlation was observed with any ODIs. In addition, when divided into two groups, BMI＜25 （non-obese group） and BMI＞25 （obese group）, the correlation was strongest with 3％ ODI_Max in the non-obese group, while the correlation coefficient was low at less than 0.4 in all ODIs.
Conclusions : The predictability of pulse oximetry prior to PSG was low for both severe OSA and obese cases. Hence, it is recommended to rely on PSG evaluation and disregard pulse oximetry results for severe OSA and obese cases.

View full abstract

Purpose : The aim of this study was to analyze the effectiveness of the Ibaraki Obstructive Sleep Apnea （OSA） Disorder Medical and Dental Cooperation Network, based on a questionnaire survey on dental sleep medicine for general practitioners.
Subjects and methods : A questionnaire survey regarding OSA was performed in 2018 on 1,326 clinics which belonged to the Ibaraki Dental Association. The results were compared between dentists who had attended the certified lecture on OSA on dental sleep medicine by the Ibaraki Dental Association （registered dentists） and those who did not （nonregistered dentists）. The questionnaire results of the registered dentists by region were statistically analyzed, both before and after construction of the network.
Results : The questionnaire results showed that 56 clinics performed oral appliance （OA） treatment, of which 33 had registered dentists and 23 did not. By region, the number of clinics performing OA treatment was statistically significantly higher in regions where certified lectures were held than in regions where they were not held （P＜0.01）. Continuous follow-up after OA treatment was performed in significantly more clinics with registered dentists （48.4%） than in those without registered dentists （8.7%） （P=0.002）. A substantial proportion of clinics （73.2%） used the monoblock type of OA in both groups. Before construction of the network system, the registration rate was 12.7%, and rates were significantly higher in regions where certified lectures were held than in regions where they were not held （P=0.01）. After construction of the network system, the registration rate increased to 17.3%, and there was no difference between the 5 original regions and the 2 regions that newly began to hold lectures, but the rate was significantly higher in these regions than in the 3 regions that did not hold the lectures （P=0.035）.
Conclusion : Our questionnaire survey demonstrated that many of the registered dentists performed continuous follow-up of the patients after OA treatment, and the registration rate increased in the regions that began to hold lectures after construction of the network system.

View full abstract

Purpose: There are subtypes of obstructive sleep apnea （OSA）: supine-predominant OSA, rapid eye movement （REM）-related OSA, and apnea-predominant OSA. Although continuous positive airway pressure （CPAP） is clearly a highly effective treatment option, various alternative treatment options exist, such as oral appliance （OA）, upper airway surgery, and hypoglossal nerve stimulation. Clinical guidelines recommend OA treatment for patients with mild to moderate OSA and those with severe OSA who are intolerant to CPAP therapy or refuse it. In recent years, differences in OA treatment efficacy depending on OSA subtype have been reported. It is necessary to understand the clinical features of different OSA subtypes. The aim of this study was to report the clinical features of REM-related OSA, supine-predominant OSA, and apnea-predominant OSA in patients requiring OA treatment.
Methods: A total of 553 patients were diagnosed with OSA by polysomnography （PSG） at the Department of Sleep Medicine of Aichi Medical University Hospital and were referred to the Department of Oral and Maxillofacial Surgery for prescription of OA. We examined clinical features such as sex, body mass index （BMI） and PSG findings for supine-predominant, REM-related OSA, and apnea-predominant OSA
Results: Supine-predominant OSA was observed in 226 （40.9％）, REM-related OSA in 128 （23.1％）, and apnea-predominant OSA in 53 （10.0%） patients. Patients with supine-predominant OSA were younger （50.6±14.9 vs. 55.5±13.9, p＝0.021） and had lower BMI （24.0±10.2 vs. 27.0±12.5, p＜0.001） than non-supine-predominant OSA. REM-related OSA was more prevalent in women than non-REM-related OSA （female ratio: 49.3％ vs. 25.6％, p＜0.001）. Patients with apnea-predominant OSA were older （61.2±13.7 vs. 55.0±14.7, p＝0.003） and had higher Epworth Sleepiness Scale scores （9.2±5.4 vs. 7.1±4.3, p＝0.014） than non-apnea-predominant OSA. Respiratory disorders in supine-predominant OSA and REM-related OSA were relatively mild to moderate and in apnea-predominant OSA tended to be severe.
Conclusions: Dentists should plan treatment strategies specific to each patient. They should sufficiently explain the justification and importance of OA treatment and the need to evaluate OA treatment using sleep tests and provide sleep dentistry through understanding of OSA subtypes. By understanding these subtypes, dentists can deepen their understanding of a patient’s specific pathology and provide high-quality sleep dentistry.

View full abstract

An abnormality of maxillofacial form, or microgenia, is known to be one of the causes of obstructive sleep apnea （OSA）. However, there has been no study on the association between jawbone form and sleep related breathing disorder （SRBD） in children, or in particular on the association between respiratory stability and the occlusal state. To elucidate the association between SRBD and the occlusal state, we conducted a large-scale questionnaire survey, examined the oral cavity and evaluated maxillofacial form, and acquired some interesting findings. This article also reports on the potential for SRBD screening through examination in dental care examination rooms.
Methods:
We examined the oral cavity of 1,146 children aged 3 to 12 years who had not received any orthodontic therapy, and conducted a questionnaire survey on their guardians. The oral cavity examination consisted of the occlusal state, Brodsky classification and Mallampati classification. The questionnaire was prepared with reference to the questionnaire items on sleep by Miyazaki, et al. （Fig. 1）.
Results:
①While 9 to 10 hours was the most frequent answer as the average hours of sleep for children aged 3 to 12 years in Japan, some children aged 6 years and younger had only 6 hours and others aged 10 years and older had 12 hours or longer.
②High values were observed for keeping the mouth open during sleep at 63.8％, keeping the mouth open during the day at 52.9％, and nasal congestion at 39.9％.
③The rate of snoring during sleep was 39.1％ and respiratory arrest 4.6％. Both were higher in male children.
④The Brodsky classification was severer with higher frequencies of snoring and respiratory arrest.
⑤We observed no correlation between Mallampati classification and snoring in this study. The number of ClassⅠ individuals was small in the respiratory arrest group.
⑥Multivariate analysis on the association between occlusion and snoring showed a correlation with reversed occlusion in 3- to 5-year-old children.
⑦A comparison of the association between occlusion and respiratory arrest revealed that children aged 8 years and older had a higher tendency to have maxillary protrusion.
Discussion:
We confirmed that snoring in children may present complications with various SRBD symptoms, and that it is an important indication for upper airway resistance syndrome （UARS）. These findings indicated the necessity of instructions on sleep hygiene in addition to the normal oral cavity examination. The symptoms that can be observed in the dental care examination room, in particular, include keeping the mouth open, having nasal congestion, lack of attention to what others say, difficulty remaining still, and getting bored easily; it is highly likely that children with these symptoms also present snoring. In such cases, measures such as more detailed medical interview and coordination with relevant medical institutes should be considered. Furthermore, our study indicated that a more detailed examination is necessary for children aged 3 to 5 years with reversed occlusion and those aged 8 years and older with maxillary protrusion.
In the future, we would like to conduct more detailed examinations and elucidate the association between jawbone form and SRBD in children.

View full abstract

Objectives: This report describes the long-term results of a patient with retrognathia treated with pre-surgical stabilization splint, mandibular advancement surgery and augmentation genioplasty. Details of the treatment course are presented to describe the advantages of splint therapy. Dimensional changes of the pharynx on lateral cephalometric X-rays were measured to investigate the effect of the splint and surgery on the airway.
Methods: Lateral cephalometric X-rays were taken at the patient’s first visit, after use of the splint, after mandibular advancement surgery, after genioplasty, and 4 years 6 months post-treatment. Anteroposterior dimensions of the upper, middle and lower part of the pharynx were measured on the X-rays and examined.
Results: All the dimensions of the pharynx decreased after using the splint, but recovered after mandibular surgery. With genioplasty, the middle part of the pharynx expanded, whereas all other dimensions were stable at 4 years 6 months post-treatment.
Conclusions: The use of the stabilization splint prior to mandibular advancement surgery made it possible to develop a more accurate surgical plan, which led to long-term skeletal and occlusal stability.

View full abstract

Purpose : We investigated actual treatments for obstructive sleep apnea （OSA） in hospital dentistry to help propose a model for integrating dentistry and medicine intermediated by hospital dentistry.
Method : A questionnaire survey of treatments for OSA was mailed to 35 members of the Ibaraki Association of Hospital Dentistry. Replies to the questionnaire were returned by facsimile, e-mail attachment, or post.
Results : Responses were obtained from 27 institutes （recovery rate 77.1%）. There were 19 institutes （70.4%） performing treatment using an oral appliance （OA）. Regarding the annual number of OA made, 14 institutes （73.7%） made 1-9, 3 institutes made 10-49, and 2 institutes made 50-99. Regarding cooperation, 9 institutes （47.4%） cooperated with other departments in the same hospital, 4 institutes cooperated with departments in other hospitals in addition to within the same hospital, 2 institutes cooperated with other special facilities for OSA besides within the same hospital, 2 institutes cooperated with all medical facilities including within the same hospital, and 2 institutes cooperated with other medical facilities only. Sixteen institutes （84.2%） used a one-piece type, 1 institute used a two-piece type only, and 2 institutes used both types. The number of institutes performing orthognathic surgery for OSA was 2 （7.4%）, which coached oral surgeons serving full-time.
Conclusion : This study showed that treatments for OSA tended to be performed more in hospital dentistry than in dental clinics. Most of the patients in hospital dentistry were treated with oral appliances （OA）, while few patients underwent surgical operation. These results may be helpful for assigning the roles of hospital dentistry in the team approach between dentistry and medicine.

View full abstract