Hereditary sensory and autonomic neuropathy types IV and V in Japan.

Hereditary sensory and autonomic neuropathy (HSAN) is a group of genetic disorders involving varying sensory and autonomic dysfunction. HSAN types IV and V are characterized by congenital generalized loss of pain and thermal sensation. HSAN type IV is additionally accompanied by decreased sweating and intellectual disability. From 2010 to 2013, we (members of the Japanese Research Group on Congenital Insensitivity to Pain) carried out research on HSAN types IV and V. Research by this group included epidemiological data, examination of clinical findings, solutions of disease etiology, investigation of complications and development of their management. Complications were categorized into musculoskeletal complications, oral/dental complications, dermal complications, ocular complications, complications resulting from impaired thermal control, anesthetic considerations, other complications possibly related to autonomic dysfunction, and abnormal mental development and behavior. Treatment and care for patients with HSAN types IV and V require a wide range of knowledge and experience, and a multidisciplinary team approach. Therefore, we produced the "Guideline of Total Management and Care for Congenital Insensitivity to Pain (Ver.1)" in 2012, to provide information for medical specialists based on our knowledge and experience. This guideline includes medical issues, as well as descriptions of social participation and welfare. This review outlines the situation of HSAN types IV and V in Japan, and the recommendations of treatment and care for patients, mostly based on research conducted by the Japanese Research Group.

Epidemiology of hereditary sensory and autonomic neuropathy type IV and V in Japan.

Hereditary sensory and autonomic neuropathy (HASN) refers to a group of rare congenital disorders characterized by loss of pain sensation and other sensory or autonomic abnormalities. Among them, a relatively large proportion of patients with HSAN type IV, which is accompanied by anhidrosis and intellectual disability, are reported from Israel and Japan. HSAN type V, with normal sweating and mental development, is rarely reported in Japan. In 2009, we founded a research group for congenital insensitivity to pain and performed the first epidemiological survey of HSAN types IV and V in Japan. Questionnaires were sent to a total of 3,488 certified training institutions of five nationwide medical societies comprising pediatricians, neurologists, orthopedic surgeons, and dentists. Answers were obtained from 1,610 institutions, and 192 HSAN patients (152 with type IV and 28 with type V) were reported from 105 institutions. After excluding duplicated patients, we identified a total of 62 current, 36 past, and five deceased patients for HSAN-IV, and a total of 14 current, 13 past, and 0 deceased patients for HSAN-V. Using these figures, we estimated that the number of Japanese patients with HSAN types IV and V as 130-210 and 30-60 patients, respectively. We identified no gender differences, and patients with a family history of the disorder were limited to affected siblings in both conditions. Most patients with HSAN-IV were 5-40 years of age, whereas half of the patients with HSAN-V were 40 years or older.

Risk factors with intravenous sedation for patients with disabilities.

The purpose of this study was to identify the risk factors associated with low peripheral oxygen saturation (SpO2) and delayed recovery of dental patients with disabilities after intravenous sedation. A total of 1213 patients with disabilities were retrospectively investigated with respect to demographic parameters and sedation conditions. Multivariate logistic analyses were conducted for patients with an SpO2 <90% and a recovery period of >60 minutes to identify the risk factors for poor sedation conditions. A significant odds ratio related to decreased SpO2 was observed for age, sex, midazolam and propofol levels, concurrent use of nitrous oxide, cerebral palsy, Down syndrome, and mental retardation. The most problematic patients were those diagnosed with Down syndrome (odds ratio, 3.003-7.978; 95% confidence interval; P < .001). Decision tree analysis showed an increased risk of decreased SpO2 in males with Down syndrome or after administration of >0.493 mg/kg propofol in combination with midazolam. An increased risk of delayed awakening was seen in patients aged less than 21 years and in males administered >0.032 mg/kg of midazolam. Intravenous sedation for dental patients with disabilities, particularly those with cerebral palsy, Down syndrome, or mental retardation, increases the risk of decreased SpO2. In addition, delayed recovery is expected after midazolam administration.

Objective assessment of internal stress in children during dental treatment by analysis of autonomic nervous activity.

AIMS: The aim of this study was to assess the internal stress of children during dental treatment based on autonomic nerve activity and facial muscle activity. METHODS: We recorded the electrocardiogram of children during the treatment of composite resin restoration and analysed autonomic nerve activity by means of power spectral analysis of heart rate variability. Simultaneously, electromyography (EMG) activity of the corrugator muscle was recorded in children during dental treatment, and the relationship between sympathetic nerve activity and corrugator EMG activity was analysed. RESULTS: In all subjects, the mean sympathetic nerve activity was significantly higher during oral examination and after treatment compared with pre-treatment. Depending on the sympathetic nerve responses to the other treatment procedures, the subjects could be classified into two groups: the stress group and the nonstress group. Sympathetic nerve activity was significantly higher during infiltration anaesthesia and cavity preparation compared with pre-treatment activity in the stress group, whereas it was consistently lower than the pre-treatment levels during most treatment procedures in the nonstress group. The mean amplitudes of the averaged corrugator muscle EMG during dental treatment did not differ between the stress and nonstress groups. CONCLUSION: The present results suggest that the measurement of autonomic nervous activity, especially sympathetic nervous activity, is quite useful in assessing the internal stress of children, even when no expressed sign of unease are present during dental treatment.

Perception of pungent, gustatory and olfactory stimuli in patients with congenital insensitivity to pain with anhidrosis.

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare disease caused by a mutation in the nerve growth factor (NGF) receptor, which results in an absence of Aδ and C fibers. It can be considered that this defect may also lead to deterioration of oral sensations. The aim of the present study was to clarify the ability of CIPA patients to perceive pungent, gustatory, and olfactory stimuli, which is essential for eating function, and the impact of the defect on dietary habits. Sensitivities to capsaicin and the five basic tastes were evaluated by measuring their threshold values, and dietary habits were examined using a questionnaire. Additionally, odor identification ability was evaluated using the odor stick method. The detection threshold for capsaicin and the recognition threshold for sour taste were significantly higher in the patients than in healthy volunteers. The questionnaire responses showed that the patients consumed spicy food more often. All patients were able to identify the tested odors, except those to which they had not been well accustomed. Since the abilities of CIPA patients to perceive taste and smell were not basically impaired, despite their lower sensitivity to capsaicin, it was suggested that their dietary habits were only minimally affected, except for intake of pungent foods.

Analysis of physiological responses associated with emotional changes induced by viewing video images of dental treatments.

Since the understanding of emotional changes induced by dental treatments is important for dentists to provide a safe and comfortable dental treatment, we analyzed physiological responses during watching video images of dental treatments to search for the appropriate objective indices reflecting emotional changes. Fifteen healthy young adult subjects voluntarily participated in the present study. Electrocardiogram (ECG), electroencephalogram (EEG) and corrugator muscle electromyogram (EMG) were recorded and changes of them by viewing videos of dental treatments were analyzed. The subjective discomfort level was acquired by Visual Analog Scale method. Analyses of autonomic nervous activities from ECG and four emotional factors (anger/stress, joy/satisfaction, sadness/depression and relaxation) from EEG demonstrated that increases in sympathetic nervous activity reflecting stress increase and decreases in relaxation level were induced by the videos of infiltration anesthesia and cavity excavation, but not intraoral examination. The corrugator muscle activity was increased by all three images regardless of video contents. The subjective discomfort during watching infiltration anesthesia and cavity excavation was higher than intraoral examination, showing that sympathetic activities and relaxation factor of emotion changed in a manner consistent with subjective emotional changes. These results suggest that measurement of autonomic nervous activities estimated from ECG and emotional factors analyzed from EEG is useful for objective evaluation of subjective emotion.

Pulpal blood flow in vital and nonvital young permanent teeth measured by transmitted-light photoplethysmography: a pilot study.

PURPOSE: The purpose of this study was to record transmitted-light photoplethysmography (TLP) from young permanent teeth and examine its applicability to pulp vitality assessment. METHODS: Twenty-six healthy and 7 nonvital upper maxillary incisors in 17 children (ages 7 years, 3 months to 14 years, 8 months) were examined. Recordings of TLP were made with and without opaque black rubber dam application in a darkened room. Finger photoplethysmography (FPP) of the participants was simultaneously recorded. RESULTS: (1) Pulse waves synchronous with FPP were recorded from all healthy teeth, whereas no pulse signals were recognized in nonvital teeth. (2) The signal amplitude in the TLP was not significantly affected by the opaque dam application. (3) In the healthy teeth, there was a significantly negative correlation between the TLP pulse amplitude and the age of the subjects. CONCLUSIONS: TLP can detect pulpal blood flow in young permanent teeth. This technique is considered to be applicable in the assessment of pulp vitality.

[Incident and accident reports in Tokyo Medical and Dental University Dental Hospital (FY 2001-2002)].

In 2002, the Dental Hospital of Tokyo Medical and Dental University set up a working group for risk management. This working group analyzed 225 incident and accident reports submitted to the hospital in 2001 and 2002. Each report was analyzed with regard to "type," "place," "reporter," "severity," and "cause" in order to diagnose hospital safety and prevent future incidents and accidents. The cause of incidents and accidents was analyzed using the SHEL model, where S stands for Software, H for Hardware, E for Environment, and L for Liveware. The severity of the consequence was classified into 6 levels, where level 0 = "error not applied," level 1 = "not affected," level 2 = "watch and see or additional test," level 3 = "treatment," level 4 = "aftereffect," and level 5 = "death." The incidents and accidents judged to have potentially high risk were given a score of "+H," irrespective of the level. The results of the analyses revealed that most of the incidents and accidents happened in "wards," "operation rooms," and "oral surgery clinics." This is probably because the incident and accident reporting system is well established by nurses working in these clinics. Additional analysis revealed that most of the reports were written and submitted by nurses. The frequencies of "treatment procedure," "misuse of dental instruments," "mis-prescription," "falling down" and "needlestick" related incidents and accidents were the highest and were caused mainly by L and S. There were only 3 accidents above level 4, however, less severe cases were given a score of +H due to the high potential risk involved.

The distribution of periodontopathic bacteria among Japanese children and their parents.

OBJECTIVE AND BACKGROUND: It is not well known how periodontopathic bacteria colonize in the oral cavity during childhood. The purpose of this study was to investigate the distribution of periodontopathic bacteria in oral cavities of children and their parents and the relationship between the bacterial findings and clinical parameters. METHODS: Fifty-six children (mean age: 8.3 +/- 3.5, range: 1-15 years), including 15 with deciduous dentition, 26 with mixed dentition and 15 with permanent dentition, and their parents participated in this study. Whole saliva and dental plaque of the children and whole saliva of their parents were collected for detection of seven species of periodontopathic bacteria (Actinobacillus actinomycetemcomitans, Tannerella forsythensis (Bacteroides forsythus), Campylobacter rectus, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens and Treponema denticola) using the polymerase chain reaction method. Clinical parameters including simplified Oral Hygiene Index and Papillary-Marginal-Attachment Index were recorded for the children and their accompanied parents. RESULTS: The detection frequencies of T. forsythensis, C. rectus, P. nigrescens, T. denticola, A. actinomycetemcomitans and P. gingivalis in the oral cavities of children were 42.9%, 94.6%, 42.9%, 48.2%, 1.8% and 8.9%, respectively. T. forsythensis, P. gingivalis and T. denticola were detected more frequently in the saliva of parents (54.8%, 54.8%, 88.1%, respectively) than in the saliva of children (25.5%, 7.3%, 41.8%, respectively). Different detection frequencies of P. nigrescens were found among the oral cavities of children with deciduous, mixed and permanent dentitions. In mixed dentition, females harbored T. forsythensis more frequently than males did. Children who harbored T. forsythensis, P. intermedia, P. nigrescens and T. denticola showed high scores for oral debris measurement by simplified Oral Hygiene Index. T. forsythensis, P. intermedia and P. nigrescens were detected more frequently in children whose parents were positive for these pathogens than in children whose parents were negative. CONCLUSIONS: High plaque retention seems to promote the colonization of periodontal pathogens in the oral cavities of children. T. forsythensis, P. intermedia and P. nigrescens were detected more frequently in the oral cavities of children whose parents already harbored these bacteria. Familial transmission of these bacteria is suggested.