• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.4
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• pp.291-314
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• 2021

Squamous cell carcinoma (SCC) of the retromolar trigone (RMT) is a rare but potentially fatal disease that carries a poor prognosis due to its unique anatomic position. RMT SCCs tend to spread to vital nearby structures, including the tonsillar pillar, masticatory muscles, and underlying mandibular bone, even in their early stages, and aggressive treatment is often warranted. This systematic review appraises and qualitatively analyzes all available literature regarding the survival outcomes and prognosis of RMT SCC. Four databases were searched to identify all eligible articles published since January 1980. Of the 1,248 studies, a total of 15 studies representing 4,838 cases met the inclusion criteria. The evaluated patients had a high rate of advanced tumor stage (T3 or T4: 61.4%), lymph node metastasis (38.8%), and mandibular bone invasion (24%) at the time of diagnosis. Aggressive surgical treatments such as lip-splitting (92%), segmental mandibulectomy (61.1%), radical neck dissection (44.1%), and reconstruction using free flaps (49.5%) was undertaken for 92% of the pooled patient population. The mean rates for local, regional, and systemic recurrence were 23.40%, 8.40%, and 8.50%, respectively. The mean 5-year overall survival rate was 38.90%. Osteonecrosis was noted in 11.6% of the 328 patients who received radiotherapy. In conclusion, RMT SCC is generally associated with high recurrence, low survival, and high postoperative complication rates. Early diagnosis and aggressive treatment are thus warranted. However, significant methodological problems hamper current knowledge. Future studies of this topic that use randomized or cohort designs are thus needed.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.95-111
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• 1997

The human speech organ consists of respiration system (lung, larynx), phonation system (vocal cord), articulation system (esophagus, pharynx, uvula, teeth, gingiva, palate, tongue, lip) and resonating system(oral cavity, nasal cavity, paranasal sinus). Because teeth are components of the articulation system, it has been reported that the persons with abnormally positioned teeth generally have abnormal occlusion and pronunciation. In this study, using /ㅅ(s)/, the most commonly mispronunced consonant in children with malocclusion, and the seven single vowels, /사(sa), 서($s\delta$), 소(so), 수(su), 스($s\omega$), 시(si), 세(se)/ and / ㅏ(a), ㅓ($\delta$), ㅗ(o), ㅜ(u), ㅡ($\omega$), 1(i), ㅔ(e)/ were recorded and analyzed using speech analysis program on computer by measuring formants and compared them for investigating the differences in pronunciation in children with Angle's class I occlusions and those with Angle's class II div.1 malocclusion. The result were as follows: 1. In the Angle's Class II div.1 group, there were no significant differences in F1 of all recorded sounds as compared with Angle's Class I group(p>0.05). 2. In the consonants, there were significant differences in F2 of /스($s\omega$)/ and F2/F1 ratio of /사(sa), 서($s\delta$), 시(si)/ between the two group(p<0.05). 3. In the vowels, there were significant differences F2/F1 ratio of /ㅓ($\delta$)/(p<0.05) and no significant differences in F2/F1 ratio between two group(p>0.05). 4. In the consonants, there were significant differences in F2 and F2/F1 ratio when succeeding vowels were high or low, and F2/F1 ratio when front in accordance with tongue position (p<0.05). 5. In the vowels, there were no significant differences in formant in accordance with tongue position(p>0.05)

• The Journal of Korean Medicine
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• v.40 no.3
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• pp.198-223
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• 2019

Objectives: The purpose of this study was to investigate the effect of Korean medicine treatment on facial asymmetric treatment in 5 cases of facial asymmetry correction by non - surgical treatment such as acupucture, chuna treatment, FCST (Functional cerebrospinal technique) and cranial osteopathy. Methods: We analyzed the initial charts of 5 patients who had undergone facial asymmetry in a Korean medicine clinic and measured the position and distance using the photograph, lateral cephalograms, and whole body radiograms. The results were as follows. Results: To quantify both soft and hard tissues to confirm the results of Korean medicine treatment of facial asymmetry, soft tissues quantitatively measure the displacement of the face, the slope of the left and right eyes, and the slope of the lip in order to grasp the positional displacement of the mandible. As a result, on the average, the correction effect as measured by the angle difference between A and C is $1.8{\pm}0.57$, the correction effect as measured by the angle difference between B and C is $1.4{\pm}0.89$, and the angle difference between D and the horizontal plane is $1.9{\pm}0.89$, and the angle difference between E and the horizontal plane is $1.9{\pm}0.89$. The result of reduced angle difference between A and C means that the head position shifted from the center of the body to the unilateral side was shifted to the center. The decrease in the angle difference between B and C means the restoration of the maxillary distortion relative to the mandible. In hard tissues, numerical values were measured based on the skull standard. The average distortion of the skull was $1.9{\pm}0.67$, and the distortion of the lower eye was $1.4{\pm}0.41$. Conclusion: General studies on facial asymmetric treatment are limited to treatments such as surgery and orthodontics. However, this study confirmed the possibility that facial asymmetry could be corrected by Korean medical treatment consisting of reversible non-surgical treatment rather than irreversible treatment such as surgery or orthodontic treatment. In particular, Korean medicine treatment is effective for muscular asymmetry, soft asymmetry, functional asymmetry, etc. The facial asymmetric treatment of Korean medicine is not limited to the face-centered correction, but the asymmetry of the whole body may be corrected as well.

• The Journal of Advanced Prosthodontics
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• v.15 no.6
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• pp.281-289
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• 2023

PURPOSE. This study aimed to predict the positional coordinates of incisor points from the scan data of conventional complete dentures and verify their accuracy. MATERIALS AND METHODS. The standard triangulated language (STL) data of the scanned 100 pairs of complete upper and lower dentures were imported into the computer-aided design software from which the position coordinates of the points corresponding to each landmark of the jaw were obtained. The x, y, and z coordinates of the incisor point (X_P, Y_P, and Z_P) were obtained from the maxillary and mandibular landmark coordinates using regression or calculation formulas, and the accuracy was verified to determine the deviation between the measured and predicted coordinate values. Y_P was obtained in two ways using the hamularincisive-papilla plane (HIP) and facial measurements. Multiple regression analysis was used to predict Z_P. The root mean squared error (RMSE) values were used to verify the accuracy of the X_P and Y_P. The RMSE value was obtained after crossvalidation using the remaining 30 cases of denture STL data to verify the accuracy of Z_P. RESULTS. The RMSE was 2.22 for predicting X_P. When predicting Y_P, the RMSE of the method using the HIP plane and facial measurements was 3.18 and 0.73, respectively. Cross-validation revealed the RMSE to be 1.53. CONCLUSION. Y_P and Z_P could be predicted from anatomical landmarks of the maxillary and mandibular edentulous jaw, suggesting that Y_P could be predicted with better accuracy with the addition of the position of the lower border of the upper lip.

• The korean journal of orthodontics
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• v.32 no.4 s.93
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• pp.241-255
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• 2002

This study was performed to evaluate horizontal and vertical characteristics according to lateral cephalometry of adult Korean skeletal Class II patients using a selected horizontal and vortical reference planes of Koreans. 60 males and 60 females consisting of freshman of Yonsei University from 1996 to 1997 and patients with history of orthognatic surgery at the Dental Hospital of Yonsei University with a skeletal Class II profile were chosen and compared with 70 males and 70 females with normal occlusion. The skeletal Class R group had the following conditions : 1. Profile composed of a retrognathic mandible or protrusive maxilla; 2. Class II molar and canine key; 3. ANB-greater than $4^{\circ}; 4$. Wits appraisal-greater than 1.0mm; Cephalometric analysis consisted of 22 skeletal, 25 soft tissue, 12 dental measurements. The results were as follows. 1. There was no considerable vortical measurement difference between the skeletal Class II malocclusion group and the normal occlusion group in skeletal analysis. But, some variations were found between the two groups in soft tissue analysis. 2. Mandibular length of the skeletal Class II malocclusion group was smaller than that of the normal occlusion group. Mandible was more posteriorly positioned in the Class II malocclusion group than in the normal occlusion group. 3. The length and antero-posterior position of the maxilla were not different between the Class II malocclusion and the normal occlusion group. 4. The antero-posterior position of the nose, upper lip and maxillary soft tissue, and nasolabial angle were not different between the two groups. 5. Mandibular soft tissue of the Class H malocclusion group was more posteriorly positioned than that of the normal. 6. The vertical measurements of the incisors(U1-HP, L1-HP) were bigger in the Class II malocclusion group than in the normal, but those of the molars(U6-HP, U6-MP) showed no significant difference between the two groups. 7 Classifying the skeletal Class II malocclusion group according to the antero-posterior position of both jaws, normally positioned maxilla and retruded mandible was 43.3%, both normally positioned maxilla and mandible 28.3%, both retruded maxilla and mandible 20.0%..

• The korean journal of orthodontics
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• v.29 no.2 s.73
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• pp.147-156
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• 1999

Skeletal Cl III malocclusion is an orthopedic appliance mainly used for growing children with maxillary undergrowth, which largely entails skeletal Cl III malocclusion. It improves anterior crossbite and maxillary position and thus, enables patients to attain favorable Profile but often involves unfavorable profile with protrusive upper and lower lips. Therefore, if orthodontists have knowledge of which condition helps obtain favorable occlusion and profile, they are able to predict the prognosis and limitation of the treatment. This study was done in order to help obtain favorable Profile after treating growing skeletal Cl III children. In the study, we classified childern into two groups, the one with favorable profile(Group 1, n=12) and the other with unfavorable profile(Group 2, n=14) and, with retrospective study using pre- and post-treatment lateral cephalogram, drew the following conclusions. 1. As patients had more serious labioversion of upper incisors, they were more unlikely to have favorable profiles after the treatment. Protrusion of prosthion, which was related with maxillary incisors, also affected profiles. 2. As the NL-ML angle before the treatment was small, it was more likely to get favorable profile. 3. As the degree of lower lip protrusion was high, it was likely to have bialveolar protrusion after the treatment. 4. As the degree of downward and backward rotation of mandible was high, it was likely to get unfavorable profile.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.303-309
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• 2013

TRAINER for Kids ($T4K^{TM}$, Myofunctional. Research Co, Australia) is a prefabricated myofunctional orthodontic appliance recommended to ClassII division1 malocclusion patients who have bad oral habits such as mouth breathing, tongue thrusting, inappropriate tongue position, thumb sucking and so on. Trainer has a soft texture and a small volume so that those advantages lead to an increase in the agreement rate of young patients of its use. This presentation is to analyze clinical efficacy of Trainer. The analysis is based on a result of regular follow-up on Class II division1 malocclusion patients who has been completely treated by Trainer in the Sanbon Dental Hospital of Wonkwang university. This case report is to present the satisfactory results gained by using Trainer on Class II patients. First, Trainer was applied in Class II malocclusion patients of mixed dentition with expected space insufficient to gain facial improvement. Second, excessive overjet, overbite were improved. Third, main effects are regarded to have been achieved by development of lingual slant of upper jaw, labial slant of lower jaw, and lower part of jaw bone.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.301-309
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• 2001

Because many of patients seeking orthodontic treatment worry about the facial appearance and their chief motivation for orthodontic treatment is facial esthetics, it is critical to understand the influence of gender or culture on the evaluation of profile esthetics. The purpose of this study was to find out any influence of gender or culture on judging good facial profile. 4 different groups were asked to evaluate 133 facial profiles to test the influence of gender or culture on judging good facial profiles. Those 4 groups consisted of 10 Korean males, 10 Korean females, 10 Korean American males, and 10 Korean American females. 2 evaluation systems were introduced, absolute and relative. Soft tissues of selected good profile group were analyzed and statistic analysis was performed. Conclusions were as follows 1. Inter-evaluator difference for judging good facial profile was statistically significant, even if there was general agreement for the best profile among 40 raters. 2. Gender difference under the same cultural environment was not significant statistically. 3. The same ethnic groups with different cultural background showed statistically different preference on judging good Profile. 4. Good facial profile group had their own characteristics compared to remaining group in several soft tissue measurements which were vertical facial ratio, soft tissue facial convexity, and antero-posterior relative lip position.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.420-426
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• 2009

The purpose of this study was to evaluate skeletal and soft tissue changes that occur after using a facemask for treatment of skeletal class III malocclusion, and to assess the relapse pattern when no retention appliance was used. Fifteen skeletal class III malocclusion patients were treated with a facemask for an average of 12 months. No retention appliance was used during the 1 year follow-up period. Cephalograms were taken during pretreatment, posttreatment, and the 1 year follow-up. Cephalograms were traced, analyzed, and the results were compared between cephalograms. All patients showed significant sagittal skeletal changes after treatment, but they also showed a significant relapse during the 1 year follow-up period when no retention appliance was used. Despite the relapse, the sagittal skeletal changes that remained were still significant. Vertical skeletal change was also significant after treatment, but the total change was not significant after a 1 year follow-up due to relapse. In soft tissue changes, facial convexity and upper lip position improved after treatment and this change remained significant after the 1 year follow-up period. Facemask therapy is therefore an effective method for treatment of skeletal class III malocclusion, however, retention is imperative to maintain the treatment effect.

• Journal of Technologic Dentistry
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• v.18 no.1
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• pp.95-115
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• 1996

The esthetic factor for the esthetic prosthesis were studied on 300 persons. The praaticipants were 150 students registered under the Deparment of Dental Laboratoy Technology, Jisan Junior College at the present day of June, 1995 and their mothers. The results were as follows; 1. The number of persons with 28 teeth in their oralcatity was highest(P<0.01). They complained that they have only 28 teeth bacaues of the loss(deficiency) fo teeth due to their impacted teeth and dental caries. 2. The presons with feelings of dissatisfaction were large in number(P<0.01). They were dissatisfied with an abnormal tooth form(33.5%), tooth position(31.7%), tooth color(31.1%), and tooth size(3.7%) in order(P<0.01). 3. In their facial form, the most numerous were men with square form and women with ovoid form(P<0.01). Among the whloe number fo facial forms it appeared to decresae in the order of ovoied(41.8%), square(32.7%), square+tapered(20.5%), and tapered form(5%)(P<0.01). In a profile form, the most numerous were men with A form and women with B. Among the whole participants the most numerous were persons with B form and persons with A and C form were next in oder of numbers(P<0.01). 4. In discoloration of teeth, the most numerous were persons who have no discoloration. 5. In the esthetic recovery of anterior prosthesis the color matching of proximal teeth was not correct, but the outline of proximal teeth was to be reproduced correctly. 6. In the diastema of teeth, the number of persons who have no diastema was higher than that of persons who have a disatema(P<0.01) Among the persons who have diastema the most numerous were persons who have a diastema, and next were 2, 4, 3 and 5 diastemas in order. 7. In a meeting point of the midline of the body and the tooth the number of person hanving a meeting point was higher than that of persons who did not fit each other(P<0.01). The bias direction of midline teeth appeared to be affected by chewing direction, prosthesis location, and posterior location. 8. The length and width of teeth in the tooth size were suitable(P<0.01). The number of persons who have central teeth longer than lateral teeth was high(P<0.0). 9. In the results of smile analysis, the line form connected with incisal edge of upper canine were parallel(P<0.01). When smile the location fo upper lips should be in accord with the central area of teeth(P<0.01) and lower lip should be atteched to the edge of anterior teeth in order to be esthetic. 10. Among the number of upper teeth we can see the most numerous were 8 teeth and next were 10, 6 and 12 in order.