A study for biofilm removing and antimicrobial effects by microbubbled tap water and other functional water, electrolyzed hypochlorite water and ozonated water.

The purpose of this study was to examine the biofilm removing and antimicrobial effects of microbubbled tap water and other functional water. The biofilm removal test showed that the activity of microbubbled tap water against the biofilm of Candida albicans and Streptococcus mutans was significantly higher than that of ordinary tap water (p<0.01). When the antimicrobial activities of two types of functional water were compared, the activity of electrolyzed hypochlorite water was significantly stronger than that of the ozonated water (p<0.01). The antimicrobial effect of the electrolyzed hypochlorite water was increased in the microbubbled form, and was stronger than microbubbled tap water. The same results were obtained not only for biofilms, but also for planktonic microbes. Our results demonstrated that the microbubbled water showed strong biofilm removing effects. Moreover, the application of functional water, such as electrolyzed hypochlorite microbubbled water was effective for both removing and sterilizing biofilms.

Elimination of transverse dental compensation is critical for treatment of patients with severe facial asymmetry.

This case report describes the importance of eliminating transverse dental compensation during preoperative orthodontic treatment for a patient with severe facial asymmetry. The patient, a 17-year-old Japanese woman, had severe facial asymmetry involving the maxilla and the mandible, and extreme transverse dental compensation of the anterior and posterior teeth in both arches. Therefore, the main treatment objectives were elimination of the transverse dental compensation by orthodontic treatment and correction of the morphology of the maxilla and the mandible by orthognathic surgery. The preoperative orthodontic treatment resulted in sufficient elimination of the transverse dental compensation and movement of the teeth into their proper positions so that basal bone firmly supported them. LeFort I osteotomy and sagittal split ramus osteotomy were performed to correct the skeletal morphology. Facial asymmetry was dramatically improved, and a favorable occlusion was obtained. At 1 year 8 months after the surgical orthodontic treatment, the facial symmetry and occlusion remained favorable. The results suggest that sufficient elimination of transverse dental compensation in the maxillary and mandibular arches during preoperative orthodontic treatment is requisite for successful treatment of severe facial asymmetry.

Asymmetry of the lips of orthognathic surgery patients.

INTRODUCTION: The purpose of this study was to examine asymmetry of the lips in patients with jaw deformity and facial asymmetry. METHODS: Pretreatment and posttreatment frontal facial photographs of 17 patients who had mandibular prognathism with facial asymmetry were analyzed. Linear and angular measurements were made on the photographs to assess the asymmetry of the lips. The upper and lower vermilion borders of the lips were divided into quadrants according to the y-axis, and each was measured. In addition, skeletal deviation (position of menton) was determined from the frontal cephalograms. RESULTS: The pretreatment linear and angular measurements showed asymmetry of the lips, but this significantly improved after treatment, and the lip form was almost symmetrical. The areas of vermilion border in the upper and lower lips became almost even during treatment. The ratio of the areas on the 2 sides was nearly 1.00. There was little correlation between the horizontal skeletal changes of menton and lip form. CONCLUSIONS: Asymmetry of the lips caused by deviation of the mandible can be almost completely corrected by orthognathic treatment.

Orthodontic treatment for oral rehabilitation after multiple maxillofacial bone fractures.

We present the orthodontic treatment of a patient with occlusal dysfunction after plastic surgery for multiple maxillofacial bone fractures caused by a traffic accident. The patient had mandibular deviation to the right because of inappropriate repositioning and fixation of the fractured bone and complete avulsion of both mandibular central incisors. The bilateral mandibular incisors, canines, and premolars were also suspected of partial avulsion or alveolar bone fracture. Several tests, including percussion and dental computed tomography, were performed on these teeth to rule out ankylosis and confirm tooth movement. Camouflage orthodontic treatment was carried out with expansion of the maxillary arch, alignment of both arches, and space closure between the mandibular lateral incisors to improve the occlusion. Good occlusion and interdigitation were obtained. Orthodontic treatment is useful for the rehabilitation of occlusal dysfunction caused by multiple maxillofacial bone fractures.

Comparison of attitudes toward orthodontic treatment between adolescents in Beijing and in Yokohama / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To compare the attitudes toward orthodontic treatment between adolescents in Beijing, China and in Yokohama, Japan.</p><p><b>METHODS</b>Standardized questionnaires were sent to 5500 adolescents in Beijing, China and 4646 adolescents in Yokohama, Japan. The data were analyzed statistically.</p><p><b>RESULTS</b>In Beijing, 3964 questionnaires were returned (72.1%) while in Yokohama, 3291 questionnaires were completed (70.8%). About 19.0% of the students had completed or were undergoing orthodontic treatment in Beijing while the corresponding figure was about 14.2% in Yokohama (P < 0.001). A higher percentage of Japanese adolescents (79.2%) valued orthodontic treatment while 66.0% of the Chinese adolescents did. The adolescents in Yokohama had more knowledge about the period of orthodontic treatment than the adolescents in Beijing. A higher percentage of Japanese adolescents (78.6%) considered that malocclusion might influence the dental health than Chinese adolescents (65.7%) did.</p><p><b>CONCLUSIONS</b>Less percentage of the adolescents in Yokohama received orthodontic treatment than those in Beijing. The percentage of Japanese adolescents satisfied with orthodontic treatment was significantly higher than that of Chinese adolescents. The adolescents in Yokohama had more knowledge about orthodontic treatment than those in Beijing. A higher percentage of Japanese adolescents considered that malocclusion might influence the dental health.</p>

The effect of ligation on the load deflection characteristics of nickel titanium orthodontic wire.

This study examined the effect of ligation on the load-deflection characteristics of nickel-titanium (NiTi) orthodontic wire. A modified three-point bending system was used for bending the NiTi round wire, which was inserted and ligated in the slots of three brackets, one of which was bonded to each of the three bender rods. Three different ligation methods, stainless steel ligature (SSL), slot lid (SL), and elastomeric ligature (EL), were employed, as well as a control with neither bracket nor ligation (NBL). The tests were repeated five times under each condition. Comparisons were made of load-deflection curve, load at maximum deflection of 2,000 microm, and load at a deflection of 1,500 microm during unloading. Analysis of Variance (ANOVA) and Dunnett's test were conducted to determine method difference (alpha = 0.05). The interaction between deflection and ligation was tested, using repeated-measures ANOVA (alpha = 0.05). The load values of the ligation groups were two to three times greater than the NBL group at a deflection of 1,500 microm during unloading: 4.37 N for EL, 3.90 N for SSL, 3.02 N for SL, and 1.49 N for NBL (P < 0.01). For the EL, a plateau region disappeared in the unloading curve. SL showed the smallest load. The ligation of the bracket wire may make NiTi wire exhibit a significantly heavier load than that traditionally expected. NiTi wire exhibited the majority of its true superelasticity with SL, whereas EL may act as a restraint on its superelasticity.

A new idea and method of tooth movement using a ratchet bracket.

Since ideally effective tooth movement in orthodontics should occur without causing damage to the periodontal ligament (PDL), a new bracket with a ratchet-locking system, the 'Ratchet Bracket', was designed to produce tooth movement while maintaining blood circulation. To define the mechanism of the appliance, a histological study was carried out on four Beagle dogs (9 months old) and a clinical study on five female patients (11 years to 38 years 10 months of age). Five upper canines in the dogs were moved 1.82 mm per month. On light microscopic observations, vascular forms showed a round-oval shape, without undermining bone resorption. No root resorption was observed in the compressed PDL at days 1, 14, and 35 of the experimental period. On fluorescent images at day 46, distinctive bone formation was apparent at the tension side. In the clinical investigation, nine upper canines in the five female patients were moved 1.92 mm per month. A wide and long alveolar hard line was seen only on the tension side of the canines on dental radiographs, indicating bodily tooth movement, without obvious signs of root resorption in all subjects. Neither spontaneous pain nor pain during biting were reported. The findings indicate that use of the ratchet bracket could result in rapid and pain-free tooth movement with vascular clarity to maintain blood circulation in the PDL.

Effects of clenbuterol and cyclosporin A on the myosin heavy chain mRNA level and the muscle mass in rat masseter.

To gain more insight into the molecular mechanism of muscle growth and fiber-type transformations, we analyzed the effects of beta(2)-adrenergic agonist clenbuterol (CB) and/or cyclosporin A (CsA), a potent inhibitor of calcineurin (CaN), on the muscle mass as well as on the mRNA levels of myosin heavy chains (MHC I, IIa, IId/x, IIb), using a real-time RT-PCR with specific primers in rat masseter. In comparison with control, the CB treatment significantly decreased the MHC I mRNA level (p < 0.01), but increased the MHC IId/x mRNA level (p < 0.01), and the CsA treatment significantly decreased the MHC I mRNA level (p < 0.05) in association with the significant decrease in MHC IIb mRNA level (p < 0.05). The CB+CsA treatment significantly decreased the levels of MHC I (p < 0.01) and IIa mRNAs (p < 0.05), but increased the MHC IId/x mRNA level (p < 0.001) in association with a significant decrease in MHC IIb mRNA level (p < 0.01), in comparison with control. The masseter muscle mass was significantly (p < 0.001) increased by either the CB or the CB + CsA treatment, but decreased with the CsA treatment (p < 0.01). These results suggest that in rat masseter muscle, CB has an anabolic action accompanying MHC mRNA I IIa IId/x sequence transition independently of CaN-signaling pathways, and CaN is involved in the type I fiber gene expression and the muscle mass maintenance of type IIb fiber.

Phosphatidylinositol-dependent bond between alkaline phosphatase and collagen fibers in the periodontal ligament of rat molars.

Alkaline phosphatase (ALP) is anchored to the outer leaflet of the lipid bilayer via phosphatidylinositol (PI) and ALP activity has been localized in the plasma membrane of numerous tissues. In the periodontal ligament ALP activity is found in the collagen fibers in addition to the plasma membrane of the osteoblasts and fibroblasts. In this study, we examined the distribution of ALP activity in the periodontal ligament of rat molars and also examined whether the bond between ALP and collagen fibers is dependent on PI by using phosphatidylinositol-specific phospholipase C (PI-PLC). ALP activity was distributed in the periodontal ligament. The activity mirrored the distribution of collagen fibers in the periodontal ligament. Cytochemical analysis also demonstrated that ALP activity was located not only in the plasma membrane of fibroblasts, but also in the collagen fiber bundles and fibrils in the periodontal ligament. After treatment with PI-PLC, the loss of ALP activity in the periodontal ligament was observed histochemically, and the loss of ALP activity in the fibroblasts as well as in the collagen fiber bundles and fibrils was observed cytochemically. These results strongly indicate that the bond between ALP and the collagen fibers is also dependent on PI.

Calcification of degenerating tissues in the periodontal ligament during tooth movement.

OBJECTIVE: Calcification of degenerating tissues in the periodontal ligament (PDL) during tooth movement was investigated longitudinally. MATERIALS AND METHODS: Upper first molars of male Wistar rats were moved lingually for 1, 7 and 21 d, following which unfixed undecalcified sections of the lingual PDL (in the pressure zone) were examined histologically, histochemically (autoradiography and electron probe microanalysis). RESULTS: On d 1 of tooth movement, degenerating tissues, together with some calcified particles, were visible in the pressure zone of the lingual PDL. On d 7, substantial calcified aggregations were seen in the degenerating tissues, predominantly situated between the bone and root. This was confirmed by the 45Ca autoradiography. On d 21 of tooth movement, large calcified aggregations were still clearly evident between the bone and root. CONCLUSIONS: This calcification of the degenerating tissues is a self-defense response of the living body to prevent direct contact between alveolar bone and the tooth root during compression of the PDL, so preventing friction between them and the development of ankylosis.

Application of thermography in dentistry--visualization of temperature distribution on oral tissues.

The purpose of this study was to devise and propose appropriate conditions for the photographing of thermal images in the oral cavity and to evaluate which thermography techniques can be applied to dentistry by evaluating the differences in temperature among oral tissues. Thermal images of oral cavities of 20 volunteers in normal oral condition were taken according to the guidelines of the Japanese Society of Thermography, with five added items for oral observation. The use of a mirror made it possible to take thermal images of the posterior portion or palate. Teeth, free gingiva, attached gingiva and alveolar mucosa were identified on thermal images. There were differences in temperature between teeth, free gingiva, attached gingiva and alveolar mucosa. These were nearly in agreement with the anatomical view. Thermography need no longer be restricted to the anterior portion using a mirror, and can now be applied to the dental region.

The reconstruction of bilateral clefts using endosseous implants after bone grafting.

This article presents the orthodontic reconstruction of an adult bilateral cleft patient with a severe Class III malocclusion in which endosseous implants were inserted after secondary alveolar bone grafting. The patient was a 21-year-old Japanese male whose lateral incisors were congenitally missing and whose premaxilla was inclined lingually. The occlusion was classified as Angle Class III with an overjet of -8 mm. Orthodontic alignment was initiated to correct the position of the maxillary incisors before bone grafting. After the anterior occlusal relationship was corrected, bilateral alveolar clefts were reconstructed by bone grafting with autogenous particulate marrow and cancellous bone harvested from the iliac crest. ITI-SLA fixtures (Institute Straumann, Waldenburg, Switzerland) (length, 10 mm; diameter, 4.1 mm) were placed into the grafted bone for prosthetic restoration of the missing lateral incisors. The results illustrate that this protocol can be expected to provide an acceptable occlusion and good dentoalveolar stability in adult cleft patients.