We clarified that tooth movement and tooth extrusion are caused by periodontitis, and that anxious tendencies are reduced after initial periodontal treatment. It has been hypothesized that tooth movement and tooth extrusion are initially induced by periodontitis, followed then by the consequent occlusal interference. The purpose of this study was to evaluate the effect of occlusal interference on the levels of stress markers in the saliva. Twenty-two healthy volunteers, consisting of 15 males and 7 females, ranging in age from 19 to 28 years, participated in the present study. We prepared a device for experimental occlusal interference, which was made of a polyester resin plate with a thickness of 1 mm. This device was set on the right first mandibular molar. All subjects were asked to fill out the State-Trait Anxiety Inventory (STAI) form for assessment of their predisposition to personal anxiety. The effects of experimental occlusal interference on occlusal force and occlusal contact area were evaluated using the Dental Prescale^® system. Parafilm-stimulated whole saliva was collected before and after the setting of the device, for measurement of the concentrations of chromogranin A, cortisol and amylase in the saliva. There were significant differences in the occlusal force and occlusal contact area before and after the setting of the device, however, we could not detect any significant differences in the concentrations of cortisol and chromogranin A. Significant increase in the concentration of amylase after the setting of the device was observed. These data suggest that stress reaction can be induced by experimental occlusal interference.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 53(2) : 113-124, 2011.

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In a previous study, we reported the results of a survey on the cooperation between dentists and dental hygienists in initial periodontal therapy. This survey included 459 dental clinics in Japan, each with at least one dentist who was a board-certified periodontist by the Japanese Society of Periodontology (JSP). In the present study, we analyzed the data obtained from the survey using factor analysis. Methods: Factor analysis using the principal factor method and varimax rotation was performed to extract factors from the survey data, and factor scores were calculated using the regression method. The relationship between the three variables from the responses and the five-factor scores were analyzed. Results: The following five factors were extracted (listed in descending order of contribution): 1) implementation of professional skills by dental hygienists; 2) involvement in treatment planning; 3) mutual trust; 4) enhancement of resources; 5) dental unit occupancy rate. Clinics that had clinic directors with over 13 years of experience showed significantly higher scores for factors 1 and 2 as compared to clinics managed by directors had less experience. Clinics with more JSP-board-certified dental hygienists, including those preparing for board certification, showed significantly higher scores for factors 1, 2 and 4. Clinics with a higher chair-time ratio for dental hygienists showed significantly higher scores for factors 1, 3 and 4. Conclusion: A team approach with proper involvement of dental hygienists is feasible in clinics with highly experienced directors, several JSP-board-certified dental hygienists, and a high chair-time ratio for dental hygienists.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 53(2) : 125-132, 2011.

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Plaque control is the most important initial treatment. Excellent plaque control is needed to accomplish successful periodontal treatment. Yokota et al. revealed that the palatal sites of the upper molars, the lingual sites of the lower molars, and the buccal sites of the upper second molars had dental plaque even after brushing by fully motivated subject. We developed a new dome-shaped modified toothbrush and investigated the efficiency of dental plaque removal using this toothbrush. Thirteen students at the school of Dental Hygiene at Kyushu Dental College who had healthy periodontium participated in the present study as subjects after providing their informed consent. The subjects were asked to stop their oral hygiene procedures for two days before the experiment. A flat-type toothbrush was used as a control. The levels of plaque present before the experiment were evaluated using the plaque control record developed by O'Leary. After tooth brushing was performed for ten minutes using the Bass technique, the ratio of plaque deposit was again evaluated, and the rate of plaque removal was compared. The modified toothbrush showed a significantly higher level of dental plaque removal than the normal flat-type toothbrush. The modified brush was more efficient, especially at the buccal sites of the upper molars, the palatal sites of the upper premolars, the palatal sites of the upper molars, the buccal sites of the lower molars, the lingual sites of the lower anterior teeth, the lingual sites of the lower premolars, the lingual sites of the lower molars, the interproximal sites of the upper molars, and the interproximal sites of the lower molars. The newly developed modified toothbrush may be a key tool for excellent plaque control.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 53(2) : 133-140, 2011.

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We report on a patient diagnosed as having severe chronic periodontitis, who showed improvement of the periodontal tissues following periodontal therapy with EMDOGAIN® (EMD) and analysis, as confirmed by dental CBCT at Kyushu University Hospital. The patient, in good general health, was a 50-year-old male and non-smoker, who presented with the chief complaint of not being able to bite on the right side. At the first examination, the mean probing pocket depth (PPD) was 4.9 mm; periodontal pockets with a depth of over 4 mm accounted for 82.7% of the total. After completion of basic periodontal therapy that included extraction of hopeless non-salvageable teeth, plaque control and full-mouth scaling and root planing, we undertook regeneration therapy with EMD for vertical bone loss, and gingival flap surgery for horizontal bone loss. After the surgery, we employed periodontal prosthetics and shifted to maintenance therapy. After 18 months, the periodontal tissue stabilized. The mean PPD was 2.2 mm and all periodontal pockets were less than 3 mm in depth. At the mesial side of tooth 25 and distal side of tooth 37, for which we used EMD, we confirmed improvement of the clinical attachment level (CAL), and confirmed the presence of regenerating bone by CB MercuRay^TM at the mesial side of tooth 25.These findings suggested that EMD and dental CBCT imaging may be useful in the treatment for periodontitis.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 53(2) : 141-153, 2011.

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Recently, a polishing brush equipped with an air scaler was introduced as an alternative to rotating instruments for Professional Mechanical Tooth Cleaning (PMTC). There is a possibility of this type of brush having an adverse effect on the tooth surface after PMTC, however, this has not yet to been confirmed. The purpose of this study was to investigate the influence of a polishing brush for PMTC equipped with an air scaler on the surface roughness of an artificial tooth substrate. In this study, stainless steel blocks with almost the same degree of hardness as human enamel and acrylic blocks with almost the same degree of hardness as human dentin were used as alternative human tooth substrates. Specimens were polished under water or with prophylactic polishing pastes (RDA #40 or #250) for 5, 10 or 15 sec, using a polishing brush equipped with an air scaler. After the PMTC, the surface roughness values (Ra) were measured with a profilometer and scanning electron microscopic observation was carried out. From the results of the surface roughness measurements, a tendency towards increase of the Ra values in the #250 group was recognized as compared with that in the other groups. The Ra values of acrylic specimens increased significantly as compared with those of the stainless steel specimens, furthermore, the Ra values of the acrylic specimens tended to increase with prolonged increasing polishing time. From the results of SEM observations, it appeared that the actylic #250 group showed a rougher surface as compared to the other groups. The results of this study suggest that the use of a polishing brush equipped with an air scaler had no adverse effects on the tooth surface texture, as long as it was used with water. However, care should be taken when using this type of polishing brush with prophylactic polishing pastes before their clinical use in clinical practice.
Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 53(2):154-162, 2011.

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