Diagnosis of dentofacial deformity needs three dimensional comprehensive understanding of craniofacial skeleton. Eventhough three dimensional computerized tomogram has been developed, the quantified measurement analysis is merely depend on cephalomeric analysis. In our pilot study using the ordinary cephalometric radiogram which is commonly used in clinical basis, we tried to reconstruct three dimensional coordinates from frontal and lateral cephalogram taken from five dry skulls attached with small metal ball. To evaluate the reproducibility of the cephalogram, intra-examiner error was measured and compared with the three dimensional coordinates. Fourteen linear measurement of dry skull and three dimensional value has been compared. The results were as follows: 1. The intra-examiner error of the two dimensional cephalogram showed a similar variation below 1 mm in frontal and lateral cephalogram. The error ranged from 0.11-0.13mm in the case of frontal cephalometrics and 0.12-0.57mm for lateral cephalometrics Three dimensional coordinates showed relatively high reproducibility except 7 coordinates out of 90 (7.8%). The average error of the single measurement of x,y,z point shown to be 0.04+/-0.21mm, 0.01+/-0.01mm. 0.08+/-0.08mm. 2. Compare the 14 linear measurement of dry skull and three dimensional measurement, the mean difference was 0.13+/-1.54mm, ranging from 2.59+/-3.00mm (L-Co, R-Co) to 0.01+/-0.38 (ANS, L-Or). From the result by taking real value percentage rate by 3 dimensional measuring value, the mean value was 100.74+/-3.92% and the measurement which showed the most shortening compared with the real value was the distance between R-Or and ANS (97.75+/-3.11%) and the most enlarged measurement was the distance between L-VMC, L-VIC (106.59+/-20.33%). 3. However, compare the real value and two dimensional cephalometric radiograph, difference between the two is significant degree which hinder the use of two dimensional measurement in clinical situation. This potential pitfall of the cephalogram might be overcome by using our three dimensional coordinate system. If the reproducibility of the frontal and lateral cephalogram is achieved, major concern related to the accuracy of three dimensional measurement is correct detection of anatomical landmark. Further investigation of anatomical investigation of facial skeleton will make this system more accurate and popular in clinical field.
Dentofacial Deformities ; Diagnosis ; Pilot Projects ; Skeleton ; Skull

dentofacial deformities. Patients were devided into two groups. One was impaction and advancement of maxilla with mandibular set-back (Group 1), the other was downward and advancement of maxilla with mandibular set-back (Group 2). Preoperative and postoperative one year cephalometric data were analyzed and compared. Results obtained were as follows: 1. The ratio of horizontal changes of soft tissue to hard tissue at Nt to ANS, Ls to UI, Li to LI, sPog to Pog were 1:0.60, 1:0.79, 1:0.47, 1:0.63 in group 1 respectively, and 1:0.59, 1:0.48, 1:0.83, 1:1.09 in group 2 respectively. Soft tissue changes were highly predictable at the upper lip, lower lip, and chin area. 2. The ratio of vertical changes of soft tissue to hard tissue at Nt to ANS, Li to LI were 1:0.72, 1:0.06 in group 1, and others showed no statistically significant difference. 3. The ratio of horizontal changes of Ls to hard tissue movements at LI(h) was 1:-0.82 in group 1 and at UI(h), LI(h) were 1:0.48, 1:0.01 in group 2. These ratios of group 1 were greater than those of group 2.4. The direction of horizontal change of Li was the same as that of hard tissue change. The ratio of horizontal changes of Li to LI was 1:0.47 in group 1 and others showed no statistically significant difference. 5. The changes of upper lip thickness and length were -1.6mm, -1.4mm in group 1, and -1mm, -2.7mm in group 2. 6. The ratios of thickness of upper lip to ANS, UI, LI were 1:-0.83, 1:-0.37, 1:0.11 in group 1. There was similar trend in group 2, and there were no statistically significant difference. These results suggest that prediction of changes in soft tissue of upper lip, lower lip, and chin were 79%, 47%, and 63% in group 1, and 48%, 83%, and 109% in group 2. There was a tendency to decrease in thickness and increase in length of the upper lip.]]>
Chin ; Dentofacial Deformities ; Humans ; Lip ; Malocclusion ; Maxilla

dentofacial deformities. Patients were devided into three groups. One was advancement group of maxilla(Group I, N=14), another was impaction group of maxilla(Group II, N=12) and the other was combination group(advancement & impaction)(Group III, N=12). Preop. and 1 month postop.(T1), preop. and 6 months postop.(T2) were analyzed and compared. The results obtained were as follows; 1. The upper lip thickness(UL-VP) moved anteriorly approximately 62% of the horizontal maxillary change and this was significant in the advancement group(Group I) 2. The upper lip length(Stm-Sn) and the lower border of upper lip(Stm) moved superiorly 25%, 40% of the maxillary impaction group(Group II) (P<0.05) 3. There was significancy in the upper lip thicness(UL-VP) approximately 56% of the combination group(Group III) (P<0.05) 4. The nasolabial angle decreased in all groups, but there were no significancy.]]>
Dentofacial Deformities ; Humans ; Lip ; Nose ; Osteotomy

BACKGROUND: The Le Fort I osteotomy is one of the most widely used and useful procedure to correct the dentofacial deformities of the midface. The changes of the maxilla position affect to overlying soft tissue including the nasal structure. Postoperative nasal septum deviation is a rare and unpredicted outcome after the surgery. There are only a few reports reporting the management of this complication. CASE PRESENTATION: In our department, three cases of the postoperative nasal septum deviation after the Le Fort I osteotomy had been experienced. Via limited intraoral circumvestibular incision, anterior maxilla, the nasal floor, and the anterior aspect of the septum were exposed. The cartilaginous part of the nasal septum was resected and repositioned to the midline and the anterior nasal spine was recontoured. Alar cinch suture performed again to prevent the sides of nostrils from flaring outwards. After the procedure, nasal septum deviation was corrected and the esthetic outcomes were favorable. CONCLUSION: Careful extubation, intraoperative management of nasal septum, and meticulous examination of pre-existing nasal septum deviation is important to avoid postoperative nasal septum deviation. If it existed after the maxillary osteotomy, septum repositioning technique of the current report can successfully correct the postoperative septal deviation.
Dentofacial Deformities ; Maxilla ; Maxillary Osteotomy ; Nasal Septum ; Osteotomy* ; Spine ; Sutures

dentofacial deformity patients. 1. Conventional nasion relator in cephalostat was used to reproduce the same head position for the same dry skull. The mean difference of the three dimensional cephalogram for the same dry skull was 0.34+/-0.33mm. Closeness of repeated measures to each skull reveals the precision of this method for the three dimensional cephalogram. 2. Concerning the accuracy, the mean difference between the three dimensional reconstruction data and actual lineal measurements was 1.47+/-1.45mm and the mean magnification ratio was 100.24+/-4.68%. This Diffrerence is attributed mainly to the ill defined cephalometric landmarks, not to the positional change of the dry skull. 3. Cephalometric measurement of lateral and frontal radiographs had no consecutive magnification ratio because of the different focus-object distance. The mean difference between the frontal and lateral cephalogram to the actual lineal measurements was 4.72+/-2.01mm and -5.22+/-3.36mm. Vertical measurements were slightly more accurate than horizontal measurements. 4. Applying to the actual patient analysis, it is recommendable to use this program for analyzing the asymmetry or spatial change after operation. The orthodontic bracket would be a favorable cephalometric landmark for constructing the three dimensional images.]]>
Dentofacial Deformities ; Head ; Humans ; Imaging, Three-Dimensional ; Orthodontic Brackets ; Skull

dentofacial abnormality.]]>
Adolescent ; Dentistry ; Dentofacial Deformities ; Humans ; Osteotomy ; Root Resorption ; Tooth

dentofacial deformity patients.]]>
Cheek ; Dentofacial Deformities ; Female ; Humans ; Male ; Orbit ; Smiling

PURPOSE: The aim of the present study was to investigate the disagreement of cephalometric analysis depending on the reference determination of midsagittal plane on three-dimensional computed tomography. MATERIALS AND METHODS: A total of 102 young women with class III dentofacial deformity were evaluated using three-dimensional computed tomography. The cranial and facial midsagittal planes were defined and the amounts of jaw deviation were calculated. The amounts of jaw deviation were compared with paired t-test (2-tailed) and Bland-Altman plot was drawn. RESULTS: The landmark tracing were reproducible (r> or =.978). The jaws relative to the cranial midsagittal plane were 10-17 times more significantly deviated than to the facial midsagittal plane (P<.001). Bland-Altman plot demonstrated that the differences between the amounts of jaw deviation from two midsagittal planes were not normally distributed versus the average of the amounts of jaw deviation from two midsagittal planes. CONCLUSION: The cephalometric analyses of facial asymmetry were significantly inconsistent depending on the reference determination of midsagittal plane. The reference for midsagittal plane should be carefully determined in three-dimensional cephalometric analysis of facial asymmetry of patients with class III dentofacial deformity.
Cephalometry ; Dentofacial Deformities ; Facial Asymmetry ; Female ; Humans ; Jaw ; Tomography, X-Ray Computed

OBJECTIVE: The purpose of this study was to assess new three-dimensional (3D) cephalometric variables, and to evaluate the relationships among skeletal and dentoalveolar variables through 3D cephalometric analysis. METHODS: Cone-beam computed tomography (CBCT) scans were acquired from 38 young adults (18 men and 20 women; 22.6 +/- 3.2 years) with normal occlusion. Thirty-five landmarks were digitized on the 3D-rendered views. Several measurements were obtained for selected landmarks. Correlations among different variables were calculated by means of Pearson's correlation coefficient values. RESULTS: The body of the mandible had a longer curve length in men (102.3 +/- 4.4 mm) than in women (94.5 +/- 4.7 mm) (p < 0.001), but there was no significant difference in the maxillary basal curve length. Men had significantly larger facial dimensions, whereas women had a larger gonial angle (117.0 +/- 4.0 vs. 113.8 +/- 3.3; p < 0.001). Strong-to-moderate correlation values were found among the vertical and transverse variables (r = 0.71 to 0.51). CONCLUSIONS: The normative values of new 3D cephalometric parameters, including the maxillary and mandibular curve length, were obtained. Strong-to-moderate correlation values were found among several vertical and transverse variables through 3D cephalometric analysis. This method of cephalometric analyses can be useful in diagnosis and treatment planning for patients with dentofacial deformities.
Adult ; Cone-Beam Computed Tomography ; Dentofacial Deformities ; Female ; Humans ; Male ; Mandible ; Young Adult

Sagittal split ramus osteotomy (SSRO) is widely used in treatment of dentofacial deformities. But, many complications can occur including unfavorable fractures during osteotomy. To prevent these complications, it is necessary to understand comprehensively the anatomy of the mandiular ramus. The purpose of this study was to evaluate the morphology of the madibular ramus in manibular prognathism patients by computed tomography comparing with normal control group. The study group consisted of 33 skeletal class III patients (20 males, 13 females) and the control group consisted of the 52 patients without dentofacial deformities (32 males, 20 females). The mean age of study group was 22.0-year old, and that of control group was 37.1-year. For the CT examination, following scan parameters was used: 1mm slice thickness, 0.5 second scan time, 120kV and 100mA/s. The axial scans of the head were made parallel to the mandibular occlusal plane. The anteroposterior length of the ramus, the distance from anterior border of the ramus to lingula, the relative distance from the anterior border of the ramus to lingula compared to the anteroposterior length of the ramus, the thickness of anterior and posterior cortical plate, the thickness of medial cortical plate of the ramus at lingula level, the thickness of cancellous bone of the ramus at lingula level were measured. The skeletal class III mandibular prognathism patients exhibited shorter anteroposterior length of the ramus, thicker anterior and posterior cortical plate, thinner mediolateral cancellous bone thickness. The lingula has a relative stable anteroposterior position in ramus in all groups. There was higher possibility of fusion of medial and lateral cortical plate at lingula level in the mandibular prognathism group. In conclusion, the mandibular prognathism patients have narrow rami with scanty cancellous bone, which means that careful preoperative examination including CT scan can prevent undesirable fractures during osteotomy.
Dental Occlusion ; Dentofacial Deformities ; Head ; Humans ; Male ; Osteotomy ; Osteotomy, Sagittal Split Ramus ; Prognathism