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It is widely accepted that the prevalence of metal hypersensitivity is increasing. Furthermore, the incidence of unerupted mandibular second molars is 2.3%, of which 0.2% is judged to be a result of impaction. While it is becoming more common to treat impacted mandibular second molars in daily clinical practice, metal hypersensitive patients presenting with unerupted molars are less frequently encountered. There have been no previous reports of patients who required mandibular molar traction and who also suffered from metal hypersensitivity. Therefore, this is the first case report to describe the long-term stability of mandibular second molar dis-impaction, leading to high level of patient satisfaction.

Background It is considered important to evaluate the ability to control lip-closing force (LCF). Objective This study aimed to investigate the ability to control directional LCF. Methods The experimental system included an apparatus developed to measure LCF during lip pursing in eight directions (upper, lower, right, left and the four directions in between) and a display showing the exerted LCF and a target value in each direction in real time. Twenty subjects (10 men and 10 women) were instructed to maintain the LCF at a specific target value using visual feedback. Based on our preliminary experiments, the target value was set as 50% of the maximum LCF, and the range was set at the target value ±8%. The accuracy rate was defined as the ratio of the matched time, in which the subject was able to keep the LCF in the target range, to the total 3 seconds. Results The accuracy rate of men was higher than in women in the lower, lower left and lower right directions. The accuracy rate of the directional LCF differed significantly depending on the direction. In assessing the accuracy rate for each directional LCF, the rates of upper and lower directional LCF were significantly higher than those of oblique directional LCF. No significant relationship was observed between the accuracy rate and the maximum LCF except for one direction in men subjects. Conclusions Our findings suggest that the ability to control directional LCF is affected by sex and the force direction.

Objectives Deterioration of lip function in the elderly is a form of oral hypofunction. It is important to understand age-related changes in lip function to improve oral health. This study aimed to quantitatively compare the maximum lip-closing force (LCF) and the ability to control LCF during voluntary lip-pursing movements between elderly and young adults and clarify the influence of aging on both measurements. Methods Using a multidirectional LCF measurement system, we measured six-directional maximum LCFs (upper, upper right, lower right, lower, lower left, upper right) of 20 healthy elderly men (69.6 ± 4.2 years) and 20 healthy young men (25.1 ± 3.8 years). The ability to control the LCF in each direction was assessed based on the accuracy rate. The directional LCF and the ability to control LCF were compared between the elderly and young adults. Results The maximum directional LCF in the elderly adults was significantly smaller than that in the young adults in three directions from the lower lip; moreover, the accuracy rate of the elderly adults was significantly lower than that of young adults in five of the six directions. Conclusions Our findings suggest that the influence of aging on the accuracy of LCF may be different from that on muscle strength. Hypofunction of the lips due to aging may result not only from decreased muscle strength but also from reduced LCF accuracy.

Dental arch morphology and tooth position are affected by lip-closing force (LCF). This study aimed to quantitatively evaluate the relationships between the horizontal or vertical balance of the LCF generated during maximum voluntary pursing-like movements and dental arch length (DAL) or width (DAW) or the lingual inclination of the upper or lower 1st molars (LIUM, LILM) in patients with Angle Class I malocclusion. Sixteen subjects with Angle Class I malocclusion (median age: 23·4 ± 5·9 years) who had never undergone orthodontic treatment were randomly selected. LCF was measured in eight directions during maximum voluntary pursing-like lip-closing movements. Dental arch models were scanned and analysed to obtain DAW, DAL, LIUM and LILM measurements. Mandibular deviation was measured on posteroanterior cephalograms. A significant negative correlation was detected between maxillary DAL and upper LCF. Maxillary DAL, DAW and the DAL/DAW ratio displayed significant negative correlations with total LCF and upper LCF. However, no significant correlations were detected between any mandibular dental arch morphological parameter and LCF. The difference in the LIUM between the deviation and non-deviation sides exhibited a significant positive correlation with the difference in upper LCF between the deviation and non-deviation sides and was significantly negatively correlated with the difference in lower LCF between the deviation and non-deviation sides. These results suggest that upper LCF is related to maxillary DAL, and the horizontal balance of the LCF of the upper and lower lips is related to the LIUM during pursing-like lip-closing movements in patients with Angle Class I malocclusion.

Purpose This study compared the incisal paths and masseter and anterior temporal muscle activity of patients with and without mandibular deviation. Subjects and methods Fourteen adult patients with mandibular protrusion with or without mandibular deviation were subjected to simultaneous measurements of their incisal paths and masseter and anterior temporal muscle activity during masticatory movements. Results The incisal paths of the deviation group (DG) were significantly more unstable than those of the non-deviation group (NDG) in the vertical direction in all sections of the mouth-opening path and from the initial to middle sections of the mouth-closing path. Horizontally, the incisal paths of the DG were also significantly more unstable than those of the NDG in all sections of the mouth-opening path and the initial and end sections of the mouth-closing path. The onset of masseter and temporal muscle activity on the working and non-working sides occurred significantly earlier in the DG than in the NDG. Conclusion The DG exhibited more unstable incisal paths than the NDG, and the early onset of masseter and temporal muscle activity observed in the DG patients during mouth closing might have been an attempt to compensate for their unstable incisal paths. This strategy might have been initiated based on information regarding the instability of the terminal position of the closing horizontal incisal path provided by periodontal sensory receptors.

Forensic facial approximation is a technique used to estimate the antemortem facial features of unknown skeletal remains. In recent years, many researchers have reported nasal tip predictions with positive results. However, the morphological nasal features of the skull can vary widely, and it is hard to obtain accurate values using facial approximation techniques. We assumed that these variations are due to an over-dependence on the values obtained from a single distance metric factor in an anatomical area. Measurements were acquired using cephalometric radiographic images obtained from 190 Japanese individuals (90 men, aged 18–36 years and 100 women, aged 18–46 years). Soft tissue and skeletal features were traced onto acetate sheets. The orbitale (Or), porion (Po), and the Frankfurt Horizontal Plane (FHP) were plotted in addition to the rhinion (Rhi), anterior nasal spine (ANS), subnasale (Sn), prosthion, and point-A (A). From these, the following were measured: a length from rhinion to prosthion; b length from rhinion to the intersection of a line perpendicular to the anterior nasal spine; c length from the prosthion to the intersection of a line perpendicular to the anterior nasal spine; g the proportion of d/b; and f the proportion of c/b. A calculation was generated from these measurements and from proportions of a–h, and applied to the samples. An R-squared (RSQ) test and standard error (SE) were used to compare the actual and predicted values. The errors observed between the predicted and actual values were not greater than 5 mm in any of the samples; 91.3% and 71.2% of predicted Sn had an error lower than 2.5 and 1.5 mm respectively, from the actual. Reliable results were obtained using the method in the present study. In addition, in the process of obtaining the measurements, we found reliable proportional differences between the sexes in the piriform and axillary alveolar regions.

The aim of this study was to examine the morphological temporomandibular joint (TMJ) changes that occur after orthodontic treatment in patients with Angle Class II malocclusion.The post-treatment changes in TMJ morphology were analyzed, based on TMJ cephalometric laminographs in 19 patients with Angle Class II malocclusion and labial inclination of the upper incisors after premolar extraction.The condylar pass angle, articular eminence to the Frankfort horizontal plane angle, and total, upper, and lower heights of the articular fossa increased significantly on both sides after treatment and retention. The anteroposterior width of the articular fossa decreased significantly on both sides after treatment and retention.These results suggest that adaptive bone remodeling of the TMJ occurs during the correction of occlusion with labial inclination of the upper incisors by orthodontic treatment after premolar extraction in patients with Angle Class II malocclusion.

Changes of temporomandibular joint (TMJ) morphology were analyzed in 21 patients with mandibular protrusion corrected using bilateral sagittal split ramus osteotomy (SSRO) and mini-plate fixation with TMJ cephalometric laminographs. The condylar pass angle, eminence to the FH plane angle, and total height of fossa and lower height of fossa in both left and right sides, significantly decreased after surgery. The width of the condyle, in both left and right sides, significantly increased after treatment. However, in the joint spaces, there were no significant differences before and after treatment. The amount of change in the eminence to the FH plane angle, total height of fossa and lower height of fossa, before and after surgery, showed significant positive correlations with that of SNB, before and after surgery. These results suggest that adaptive bone remodeling of the TMJ might occur due to the correction of occlusion and craniofacial morphology by SSRO in patients with mandibular protrusion.

Introduction The aim of the present study is to evaluate an esthetic smile in young Japanese women, which is not yet clear.

Facial reconstruction is a forensic anthropological technique based on a database of facial soft tissue thickness; however, the information available is generally insufficient to completely reconstruct facial features. While most soft tissue in the craniofacial region is strongly adherent to the bony surface, a few areas, such as the ears, nose, and lip regions, are not. Yet these are vital features for forensic identification and are used in everyday life in facial recognition. For such features, forensic anthropologists investigating age, sex, ancestry, and facial appearance must often rely upon bony information alone. Determination of nasal tip position in adults from the skull has been reported by several researchers. However, data for determining nasal tip position from the juvenile skull have not been reported. The aim of this study was to establish and apply a simple discriminative method of identification of nasal tip location in unidentified juvenile human skeletal remains through an investigation of the cranial base in the current Japanese juvenile population. The result would be applicable for not only the research described above but also estimation of growth of mid facial profile (i.e. estimation of patterns of bony and cartilaginous framework of the nose by diseased palatal clefts etc.) and aesthetic standards. Lateral cephalometric X-ray images were used to measure soft tissue thickness in subjects undergoing orthodontic treatment. Two reference planes were set on the skull radiograph (one had already been set at the beginning of facial reconstruction). After tracing the facial profile and plotting soft tissue and bony landmarks, nine dimensions of distances (length and length ratio) and angles between these landmarks and the nasal tip were measured. A prediction function for the nasal tip was derived from these measurements. This study reports a simple and reliable method of nasal tip prediction for use in forensic facial reconstruction from incomplete human juvenile skulls.

Facial reconstruction techniques used in forensic anthropology require knowledge of the facial soft tissue thickness of each race if facial features are to be reconstructed correctly. If this is inaccurate, so also will be the reconstructed face. Knowledge of differences by age and sex are also required. Therefore, when unknown human skeletal remains are found, the forensic anthropologist investigates for race, sex, and age, and for other variables of relevance. Cephalometric X-ray images of living persons can help to provide this information. They give an approximately 10% enlargement from true size and can demonstrate the relationship between soft and hard tissue. In the present study, facial soft tissue thickness in Japanese children was measured at 12 anthropological points using X-ray cephalometry in order to establish a database for facial soft tissue thickness. This study of both boys and girls, aged from 6 to 18 years, follows a previous study of Japanese female children only, and focuses on facial soft tissue thickness in only one skeletal type. Sex differences in thickness of tissue were found from 12 years of age upwards. The study provides more detailed and accurate measurements than past reports of facial soft tissue thickness, and reveals the uniqueness of the Japanese child’s facial profile. # 2007 Elsevier Ireland Ltd. All rights reserved.

The aim of this study was to investigate, in a rat model, the effects of age on the amount of tooth movement and concomitant changes in alveolar bone turnover activity adjacent to orthodontically treated tooth roots. Rats (n = 48) of four different age groups (10, 30, 50, and 80 wk of age) were used in the experiment. Maxillary first molars were tipped mesially with a nickel titanium alloy coil-spring for 2 wk by a continuous force of 10 cN. Forty-eight age-matched untreated rats were used as controls. The changes in alveolar bone turnover were assessed histomorphometrically. Two weeks after the start of tooth movement, the amount of tooth movement was found to decrease with age and was significantly different among the four age groups. The histomorphometric study demonstrated that, in all experimental groups, turnover of alveolar bone increased significantly compared with that of each age-matched untreated group. However, the rate of increase decreased in an age-related manner. These results suggest that the age-dependent decrease in alveolar bone turnover activity, in response to mechanical forces, may negatively affect the amount of tooth movement.

Skull-photo superimposition is a technique used to identify the relationship between the skull and a photograph of a target person: and facial reconstruction reproduces antemortem facial features from an unknown human skull, or identifies the facial features of unknown human skeletal remains. These techniques are based on soft tissue thickness and the relationships between soft tissue and the skull, i.e., the position of the ear and external acoustic meatus, pupil and orbit, nose and nasal aperture, and lips and teeth. However, the ear and nose region are relatively difficult to identify because of their structure, as the soft tissues of these regions are lined with cartilage. We attempted to establish a more accurate method to determine the position of the nasal tip from the skull. We measured the height of the maxilla and mid-lower facial region in 55 Japanese men and generated a regression equation from the collected data. We obtained a result that was 2.0±0.99mm (mean±SD) distant from the true nasal tip, when applied to a validation set consisting of another 12 Japanese men.

The effects of 2-year orthopedic treatment with a chin cup appliance were compared between: Group 1, 35 female patients from a private clinic who showed excellent compliance; Group 2, 31 female patients from a dental hospital, whose compliance ranged from good to fair; Group 3, an untreated control sample of similar female patients. All patients had anterior cross-bite and a negative ANB angle of at least −2°. The first group was treated with an aggressive protocol: 14 h a day for 2 years, force of 250–300 g, frequent monitoring to ensure compliance for the full 2 years and commitment to overtreatment of skeletal Class III malocclusion to improve stability. The second group was treated with a more routine protocol: night-time wear for 2 years, force of 500 g, commitment to correcting the anterior cross-bite (year one) with compliance tapering off in the second year. The third group was a cross-sectional sample of untreated females with similar Class III malocclusions. Group 1 showed significantly more skeletal correction. It was concluded that an aggressive protocol of chin cup therapy for 2 years is an orthopedic solution for developing Class III malocclusions.

Dielectric properties of [Co(H 2 N(CH 2 ) 2 NH 2 ) 3 ](NO 3 ) 3 (ethylenediamine cobalt nitrate, ECN) single crystals have been investigated. Dielectric constants measured at 10 kHz exhibited anomalies around 110 K and 140 K in addition to a tiny anomaly at 250 K. Dielectric dispersion measurements in the frequency range from 100 Hz to 1 MHz have been performed between room temperature and 20 K to investigate the mechanism of the dielectric anomalies. Two Debye-type relaxation modes with rather long relaxation times were found The temperature dependence of the dielectric strengths, relaxation times, indices for distribution of relaxation time was determined.

Facial reconstruction is used in forensic anthropology to recreate the face from unknown human skeletal remains, and to elucidate the antemortem facial appearance. This requires accurate assessment of the skull (age, sex, ancestry, etc.) and thickness data. However, additional information is required to reconstruct the face as the information obtained from the skull is limited. Here, we aimed to examine the information from the skull that is required for accurate facial reconstruction. The human facial profile is classified into 3 shapes: straight, convex, and concave. These facial profiles facilitate recognition of individuals. The skeletal classes used in orthodontics are classified according to these 3 facial types. We have previously reported the differences between Japanese females. In the present study, we applied this classification for facial tissue measurement, compared the differences in tissue depth of each skeletal class for both sexes in the Japanese population, and elucidated the differences between the skeletal classes.

A 50-year-old man was admitted to the hospital because of epigastric pain and hyperamylasemia. Abdominal CT and ultrasonography revealed few polyps in the gallbladder. ERCP film showed the common channel of 23mm in length and common bile duct of 8mm in width. A diagnosis of anomalous arrangement of the pancreaticobiliary duct without dilation of the common bile duct was made. The values of amylase of bile juce were 9, 700 IU/l in the gallbladder and 177, 700 IU/l in the common bile duct. So cholecystectomy with resection of the extrahepatic common bile duct and hepatico-jejunostomy were performed. By histopathologic study a papillaryadenocarcinoma (m, ly0, v0) was found in a part of the gallbladder well. In a review of the Japanese literaure, only 11 cases of early cancer of the gallbladder assosiated with anomalous arrangement of the pancreaticobiliary duct without diliation of the common-bile duct could be seen.

Objective: To test the null hypothesis that premolar autotransplantation is not successful for orthodontic patients. Materials and Methods: In the present study, 28 premolar transplants from 24 orthodontic patients were associated with orthodontic treatment. At a routine 3-month appointment, patients underwent a dental radiograph and a chair-side observation for periodontal problems. Three sets of dental radiographs were taken by one dental assistant using a custom holder at: preoperation (T0), 2 year postoperation (T1), and retention (T2) (4- to 14-year follow-up observation) stages. All transplants were conducted in a one-phase operation by one operator (Dr Inoue). Recipient sites were: ten for missing maxillary canines, nine for maxillary centrals and laterals, eight for lower second premolar, and five for other missing premolar sites. All recipients maintained the retained primary tooth with a socket. Results: The success ratio of all 28 transplants was 100%, although four transplants shorter than a 4-year period of observation were omitted. Two transplant patients, one with a medical history of histiocytosis and the other with a history of osteomyelitis of the maxilla without a recipient socket, were also excluded from this study. Eleven of 22 premolar transplants had a root canal treatment (RCT), four of which had RCT within 2 years after the operation. Conclusions: The null hypothesis was rejected. The success ratio of premolar transplants was 100%.

The effect of age on alveolar bone turnover adjacent to maxillary molar roots of male rats was assessed histomorphometrically with special focus on bone formation and resorption.A total of 110 male Wistar rats ranging in age from 6 to 100 weeks were used for this study. Histomorphometric parameters were measured in fluorescence-labeled undecalcified ground and paraffin-embedded decalcified sections of the alveolar wall around the disto-lingual roots of the maxillary first molars. Bone formation was measured statically by determining the percentage of the bone surface that was double-labeled surface (dLS/BS), bone formation rate (BFR/BS), and mineral apposition rate (MAR). Bone resorption was quantified statically in terms of the number of osteoclasts (N.Oc/BS) and the percentage of the bone surface covered with osteoclasts (Oc.S/BS).For the total surface of the alveolar wall, the values obtained for all parameters of both bone formation and resorption decreased with advancing age. All these values rapidly decreased during the early part of the life span, from 6 to 30-40 weeks of age, of the rats. A site-specific difference between the distal and mesial sides of the alveolar wall was found for each age group. dLS/BS and BFR/BS were significantly greater (p0.0001) on the mesial side than on the distal one. On the other hand, the distal side showed significantly greater (p0.0001) value for N.Oc/BS and Oc.S/BS did the mesial one. However, there were no significant age-related changes in dLS/BS and BFR/BS on the distal side or in N.Oc/BS and Oc.S/BS on the mesial side throughout observation period.The results of the present study demonstrate that alveolar bone turnover of male rats decreased rapidly with advancing age but that in order to maintain the integrity of the tooth function mechanical stress may still have participated in bone formation and resorption of the alveolar wall even in rats 100-week old.

This study examines cephalometric differences and sex differences in the long-term outcome of chin cup treatments of Class III subjects with two facial patterns. Seventeen nondolichofacial and 16 dolichofacial Class III male patients and 16 nondolichofacial and 16 dolichofacial female patients were treated by either bicuspid extraction or nonextraction. Rapid palatal expansion without maxillary protraction was performed on 11 male cases and 15 female cases. The borderline between the two groups was drawn either at 39 degrees mandibular plane angle or 132 degrees (male subjects) or 130 degrees (female subjects) gonial angle. Dolichofacial subjects were treated with either an occipital or a high-pull chin cup force during the first two years, followed by high-pull force during night-time wear for the subsequent three years. All treated cases showed excellent results in the retention records with acceptable posterior occlusion as well as excellent skeletal and soft-tissue profiles. In addition, patient compliance was excellent. The treatment outcomes of the two groups showed significant improvement of the skeletal Class III malocclusion. This study indicated that the treatment period and wear time of the chin cup appliance in nondolichofacial (mostly mesiofacial pattern) patients could be shorter than those of dolichofacial patients. Although all subjects showed significant improvement in the Class III malocclusion, the treatment outcome in the two groups maintained the original characteristic skeletal morphology at retention.

Introduction: Dolichofacial skeletal patterns are a challenge for the orthodontist. Even when treatment for a long-face patient begins before the adolescent growth spurt, excellent compliance is generally needed. The patient whose care is presented here started treatment at age 14. Results: The extraction of 4 premolars, rapid palatal expansion, and excellent compliance wearing a combination occipital and vertical-pull chincup over a 2-year period led to good results at age 16, with minimal dental or skeletal relapse at age 18 years 5 months.

Introduction: The objective of this study was to evaluate dental arch forms associated with various facial types in adolescents with Class II Division 1 malocclusions by using mathematical functions to describe the arch form at clinical bracket points. Methods: Pretreatment lateral cephalograms and dental study casts of 73 white Brazilians were divided into 3 groups according to facial type: 17 brachyfacial, 24 mesofacial, and 32 dolichofacial. Fifteen landmarks on each dental cast were digitized. Computer-generated mathematical arch forms (fourth-degree polynomial equation and beta function) were used to evaluate arch form differences by superimposition. Results: The constant term related to dental arch depth of the brachyfacial subjects was significantly greater than that of the mesofacial subjects in the maxillary arch ( P = .004). Superimposition of maxillary arch analysis showed that the posterior segment width of the mathematically computed arch form tended to increase from dolichofacial type to brachyfacial type. The arch forms drawn by the 2 equations coincided at the incisal and molar regions. Conclusions: The beta function is appropriate for predicting the finishing arch form, and the polynomial equation is appropriate for the analysis (diagnosis) of various Class II malocclusions, including ovoid, tapered, and square arch forms and dental arch asymmetry.

In orthodontic diagnosis, an accurate assessment of the amount of discrepancy is necessary to flatten the curve of Spee (CS). This discrepancy could be calculated by a formula for changing from the...

The purpose of this study was to investigate the current opinions regarding post-orthodontic patients and their guardians. A questionnaire for collecting demographic and behavior variables was used...

Facial reconstruction techniques used in forensic anthropology are based on mean soft tissue thickness measurements. Numerous studies of facial tissue thickness in adults have been published on a range of subjects from different ancestral backgrounds. Data on facial thickness in children derive primarily from Caucasoid, African-American, and Hispanic subjects. There are limited data from the few studies of Japanese children (male: skeletal class I only; female: all skeletal classes). The author has previously reported facial tissue thickness data for Japanese girls and boys with skeletal class I and for all three skeletal classes in Japanese girls. The present study reports facial soft tissue thickness data in Japanese children of all skeletal classes, within age subsets. With parental informed consent, diagnostic lateral cephalometric X-ray images were obtained from 339 Japanese children aged 7-18 years (male: 162; female: 177) who attended the Matsumoto Dental University Department of Orthodontics to undergo orthodontic treatment. Soft tissue and skeletal features were traced onto acetate sheets from the X-ray images, and 10 anthropological landmarks on the midsagittal line were measured. Means, SDs, and ranges were then calculated. Differences between male and female measurements in six age groups were compared using t-tests. Significant differences were observed at some landmarks in each age group. The findings were compared with data from other juvenile populations.

Facial reconstruction is a technique used in forensic anthropology to estimate the appearance of the antemortem face from unknown human skeletal remains. This requires accurate skull assessment (for variables such as age, sex, and race) and soft tissue thickness data. However, the skull can provide only limited information, and further data are needed to reconstruct the face. The authors herein obtained further information from the skull in order to reconstruct the face more accurately. Skulls can be classified into three facial types on the basis of orthodontic skeletal classes (namely, straight facial profile, type I, convex facial profile, type II, and concave facial profile, type III). This concept was applied to facial tissue measurement and soft tissue depth was compared in each skeletal class in a Japanese female population. Differences of soft tissue depth between skeletal classes were observed, and this information may enable more accurate reconstruction than sex-specific depth alone.