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To evaluate the morphological changes in the lips and to determine the degree of improvement in the smile after orthodontic treatment for Class II division 1 malocclusion.The sample subjects were divided into two groups: a group that consisted of 20 adult female patients with Angle Class II division 1 malocclusion and a control group that consisted of 28 adult female volunteers with normal occlusion. Frontal photographs were taken before and after orthodontic treatment, and 35 landmarks were placed on each tracing made from the photograph. Thereafter, landmarks were digitized into an x- and y-coordinate system with the subnasal point as the origin. The comparisons between pretreatment and posttreatment at rest and on smiling, and the comparisons between Class II division 1 and control group were made using Student's t-test.Both the upper and lower lips in the smile of patients in the Class II division 1 pretreatment group were positioned downward, and the upward movement of the upper lip and mouth corners was smaller in comparison with the control group. These characteristics of the Class II smile improved after orthodontic treatment, but the differences with the control group remained unchanged immediately after treatment.The soft tissue morphology shows a relative improvement after orthodontic treatment.

The purpose of this study was to test the hypothesis that there is a relationship between the temporomandibular joint (TMJ) osteoarthritis/osteoarthrosis (OA), head posture and dentofacial morphology.Case-control study.The subjects consisted of 34 Japanese females with TMJ OA (aged 24.7 +/- 6.1 years) and a control group of 25 healthy Japanese females (aged 23.6 +/- 1.3 years). Six cranio-cervical angular measurements were constructed for head posture analysis. Nine angular and three linear measurements were constructed for the skeletal hard tissue analysis. Five angular and one linear measurements were constructed for the dental hard tissue analysis. Unpaired t-tests were used to compare the mean differences of head posture measurements and dentofacial cephalometric measurements between the TMJ OA and the control group.The TMJ OA group had significantly larger cranio-cervical angles (p0.05) and had more posteriorly rotated mandibles (p0.0001) than those in the control group. They also had a significantly shorter posterior facial height (p0.0001). The TMJ OA group had more retroclined lower incisors (p0.05).These results suggest that an association may exist between TMJ OA, head posture and dentofacial morphology.

Objective: To test the hypothesis that there is no difference in the stability of the hard and soft tissue changes following a surgical mandibular setback using a sagittal split ramus osteotomy or an intraoral vertical ramus osteotomy. Materials and Methods: The samples consisted of 45 female patients with mandibular prognathism, who were divided into two groups. Twenty-three underwent a sagittal split ramus osteotomy (SSRO) with rigid fixation by titanium mini-screws and maxillomandibular fixation (MMF) for 14.0 ± 0.7 days. Twenty-two underwent intraoral vertical ramus osteotomy (IVRO) without rigid fixation, and MMF was released 21.5 ± 3.3 days after surgery. Data were collected from standardized cephalometric radiographs taken at the start of preoperative orthodontic treatment (T1), immediately after surgery (MMF, T2), and the completion of postoperative treatment (T3). Angular measurements were compared on each of T1, T2, and T3. Results: There were no significant differences in the pretreatment hard and soft tissue morphology between the SSRO and IVRO. However, when fixation was released, the mandible was posteriorly positioned in the IVRO group. In the soft tissue profile, the mental region was located backward in the IVRO group at postoperative stage (T3). Conclusions: The hypothesis is rejected. The soft tissue profile of the IVRO group especially showed a retromandibular position after postoperative treatment in comparison with the SSRO group. This tendency of the IVRO group would contribute to the database for treatment planning and prediction.

Structured Abstract Authors – Ioi H, Nakata S, Nakasima A, Counts AL Objective – The purpose of this study was to assess and determine the range of the top three most-favored facial profiles for each sex from a series of varying facial convexity, and to evaluate the clinically acceptable facial profiles for Japanese adults. Design – Questionnaire-based study. Subjects and methods – Silhouettes of average male and female profiles were constructed from the profiles of 30 Japanese males and females with normal occlusions. Chin positions were protruded or retruded by 2°, 4°, 6°, 8° and 10°, respectively, from the average profile. Forty-one orthodontists and 50 dental students were asked to select the three most-favored profiles for each sex, and they were also asked to indicate whether they would seek surgical orthodontic treatment if that image represented their own profile. Results – For males, both the orthodontists and dental students chose the average profile as the most-favored profile. For females, both the orthodontists and dental students chose a slightly more retruded chin position as the most-favored profile. Japanese raters tended to choose class II profiles as more acceptable profiles than class III profiles for both males and females. Conclusions – These findings suggest that Japanese patients with class III profiles tend to seek surgical orthodontic treatment more often.

Introduction : Mutations involving the KCNH2 gene in HERG channel are responsible for type2 LQTS. Previous study showed patients with mutations in the pore region of the HERG gene are markedly increased risk for arrhythmia-related cardiac events compared with patients with nonpore mutations. However, a few data exist regarding mode of onset and frequency in arrhythmic events of mutations in the nonpore regions of the HERG channel. Hypothesis :We hypothesized that patients with mutations in the nonpore regions of the HERG gene increase risk for cardiac events under a specific condition. Methods: We examined 104 unrelated subjects with LQTS. Genetic analysis of KCNH2 gene was performed using standard genetic tests for probands and families of genotyped ones.Between subjects with and without pore mutations,difference in clinical characteristics such as QTc intervals, LQT score and major cardiac events are evaluated by standard statistical methods. Result: We identified 7 LQT2 patients with 3 pore mutations and 17 patients with 7 nonpore mutation, and evaluated clinical characteristics and characterized the electrophysiological properties of these mutations. The baseline QTc intervals were significantly longer with pore than with nonpore mutations (513 ± 60ms vs. 479 ± 21ms, p Conclusions: These data demonstrate that LQT2 patients with nonpore mutations are also at high risk of arrhythmia-related events in the presence of drugs or other environmental stressors.

Introduction Traditionally, cephalograms have been used to evaluate a patient's maxillofacial skeleton and facial soft-tissue morphology. However, magnification and distortion of the cephalograms make detailed morphologic analysis difficult in patients with complex deformities. The purpose of this article was to introduce a new method for visualizing deformation and deviation of the maxillofacial skeleton and facial soft tissues. Methods Standard 3-dimensional Japanese head models were sized to match the sella-to-nasion distance obtained from 2 patients' (1 man, 1 woman) maxillofacial skeletal images. Then, the scaled standard model was superimposed on each patient's 3-dimensional computed tomography image. Results This system provided clear shape information independent of size and facilitated the visualization of shape variations in maxillofacial skeletal and facial soft-tissue morphology. Conclusions This method will be useful for 3-dimensional morphologic analysis of patients with jaw deformities.

Objective: To determine whether there is an association between temporomandibular joint (TMJ) osteoarthritis/osteoarthrosis (OA) and immune system factors in a Japanese sample. Materials and Methods: The records of 41 subjects (7 men, aged 22.0 ± 3.8 years; 34 women, aged 24.8 ± 6.3 years) and 41 pair-matched controls (7 men, aged 22.1 ± 2.3 years; 34 women, aged 24.8 ± 6.4 years) based on age and gender were reviewed. Information on medical history included local or systemic diseases, details on medication type and use, and the presence of allergies and asthma. Dental history questions referred to details regarding past oral injuries. The validity of the hypothesis, defining allergies and asthma as risk factors in OA, was tested by using a logistic regression analysis. Results: The incidence of allergy was significantly higher in the TMJ OA (P = .008), with a mean odds ratio of 4.125 and a 95% confidence interval of 1.446–11.769. Conclusion: These results suggest that allergy may be a risk factor in association with TMJ OA in this Japanese sample.

To compare the lip positions found in two ancient Buddha statues with the lip positions in contemporary Japanese adults.The facial profiles of Yakushi-ji temple Sho Kannon (male) and Chugu-ji temple Bodhisattva (female), generally considered to be two of the most beautiful Buddha statues in existence, were compared with the facial profiles of 30 Japanese dental students. Profiles of the statues were measured on photographs and profiles of the adults on cephalometric radiographs. The adults comprised 15 men between 22 and 26 years of age (Mean age: 23.8+/-1.3 years) and 15 women between 22 to 25 years of age (Mean age: 22.9+/-1.0 years).The Buddha statues had retrusive lips compared with the lip positions in contemporary Japanese adults.Flat profiles may be favoured by Japanese adults who, typically, have protrusive lips.

Many researchers have attempted to clarify the complex relationships between stomatognathic function and craniofacial morphology. Most studies investigated the trajectories of incisal or condylar points and measured temporomandibular morphology projected onto 2-dimensional radiographic films. Although these methods provided valuable information, their diagnostic capabilities were limited. We introduce a new 4-dimensional (4D) analysis of stomatognathic function that combines the 3-dimensional (3D) computed tomography of the cranium and mandible, dental surface imaging with a noncontact 3D laser scanner, and mandibular movement data recorded with a 6 degrees of freedom jaw-movement analyzer. This method performs dynamic and precise simulations that can analyze and display condyle to fossa distances and occlusal contacts during mandibular function. These comprehensive relationships can be analyzed and displayed not only at intercuspal position, but also at any mandibular position during functional movements. We believe that our 4D analyzing system will be useful for diagnosing temporomandibular disorders of patients with jaw deformities and other malocclusions.

Introduction: A consensus on the contemporary perception of beauty might have been developed between different countries because of increased worldwide access to variations in pleasing facial profiles. The objectives of this study were to determine, assess, and compare the ranges of values of the most-favored facial profiles rated by young Korean and Japanese adults. Methods: Average profiles were constructed from the profiles of 30 Japanese men and women with normal occlusions. A series of 13 profiles each was developed for men and women. In the series, the average profile was located in the center (number 7), and the lips were protruded or retruded in 1-mm increments from the average profile. Forty-six Korean dental students and 52 Japanese dental students were asked to rate the top 3 most-favored profiles. Results: Both the Korean and the Japanese dental students tended to select a slightly more retruded lip profile compared with the averages for men and women, and the tendency to prefer a more retruded lip position was evident for the women. Conclusions: These findings suggest that young Korean and Japanese adults prefer a retruded profile, even though their profiles have historically been characterized by more convex facial features.

The objective of this study was to determine whether there is an association between excessive root resorption and immune system factors in a sample of Japanese orthodontic patients. The records of 60 orthodontic patients (18 males, age 17.7 +/- 5.7 years; 42 females, age 16.4 +/- 6.0 years) and 60 pair-matched controls (18 males, age 15.9 +/- 4.5 years; 42 females, age 18.5 +/- 5.2 years) based on age, sex, treatment duration, and the type of malocclusion were reviewed retrospectively. The validity of our hypothesis was tested using the logistic regression analysis. The pretreatment records revealed that the incidence of allergy and root morphology abnormality was significantly higher in the root resorption group (P = .030 and .001), with a mean odds ratio of 2.794 and 6.317 and 95% confidence interval of 1.107-7.053 and 2.043-19.537, respectively. The incidence of asthma also tended to be higher in the root resorption group. From these results, we concluded that allergy, root morphology abnormality, and asthma may be high-risk factors for the development of excessive root resorption during orthodontic tooth movement in Japanese patients.

Introduction: Traditionally, lateral and frontal cephalograms are used with facial photographs to evaluate a patient's maxillofacial skeletal and facial soft-tissue morphology. However, the enlargement and distortion of 2-dimensional radiography made it difficult to accurately conceptualize the patient's anatomy. The purpose of this article was to introduce a new method for comparing 3-dimensional (3D) standard values of the maxillofacial skeletal and facial soft-tissue morphology before and after orthognathic surgery. Methods: Normative 3D standard values of the maxillofacial skeletal and facial soft-tissue morphology were calculated from normal women. The pre- and postoperative morphology of one woman who underwent orthognathic surgery was compared with the normative data. Results: This 3D analysis has clinical value to evaluate patients before and after surgical treatment. Conclusions: This quantitative assessment of 3D maxillofacial morphology can evaluate the area and degree of displacement and rotation of the facial skeleton and facial soft tissues. This method is sufficiently useful for routine clinical applications.

Soft tissue analyses are basic tools in planning orthodontic treatment. However, the perception of a well-balanced Japanese facial profile has not yet been established, particularly with respect to changes in facial convexity. The purpose of this study was to assess and determine the range of antero-posterior (A-P) lip positions of the top three most favored, well-balanced profiles from a series of various facial silhouettes with changing facial convexity. The average profile was constructed from the profiles of 30 Japanese males and females with Class I occlusions. Changes in facial convexity were established by altering the A-P chin position by protruding or retruding the chin in increments of 5 degrees and 10 degrees from the average profile. A series of 11 profiles were developed from each of the four changes in facial convexity. The lips were then protruded or retruded in one-mm increments from the average profile. Forty orthodontists were asked to rate the top three most favored, well-balanced profiles. We found that the raters tended to prefer more retruded lip positions as facial convexity decreased, for both males and females. The raters also tended to prefer slightly more protruded lip positions as the facial convexity increased. Because chin position is inherent in each patient, others may equate a retrusive or protrusive chin with certain personalities, thus, it is important for orthodontists to take into account the balance between the lips and the chin.

Purpose: Three-dimensional (3D) computer models of the human craniofacial structure have been constructed with computed tomography (CT). However, the high cost of CT and the radiation exposure are drawbacks to this method. Attempts to create a 3D reconstruction from lateral and frontal cephalograms have failed because of problems with magnification, distortion, and limitations of landmark identification, among others. We introduce a new method that creates a standard head model for a patient from anatomic measurement points extracted from x-ray images, facial stereo photographs, and dental casts. Material: To obtain precise 3D coordinates from cephalograms, several equations were introduced to compensate for radiographic image magnification and distortion. Results: By comparing the constructed model and 3D-CT images, this method proved to be accurate. Conclusions: It is possible to produce a 3D head model on a personal computer and to view it from any desired angle; this will provide easy-to-understand information for patients and establish a diagnostic or therapeutic method for communication with other health care providers.

A person with an asymmetric morphology of maxillofacial skeleton reportedly possesses an asymmetric jaw function and the risk to express temporomandibular disorder is high. A comprehensive analysis from the point of view of both the morphology and the function such as maxillofacial or temporomandibular joint morphology, dental occlusion, and features of mandibular movement pathways is essential. In this study, the 4D jaw movement visualization system was developed to visually understand the characteristic jaw movement, 3D maxillofacial skeleton structure, and the alignment of the upper and lower teeth of a patient. For this purpose, the 3D reconstructed images of the cranial and mandibular bones, obtained by computed tomography, were measured using a non-contact 3D measuring device, and the obtained morphological images of teeth model were integrated and activated on the 6 DOF jaw movement data. This system was experimentally applied and visualized in a jaw deformity patient and its usability as a clinical diagnostic support system was verified.