• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.5
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• pp.324-328
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• 2009

Submentovertex(SMV) projection shows the base of skull, positions of mandibular condyle and zygomatic arches. We would like to investigate how to use SMV and evaluate its availability for the construction of the plan for orthognathic surgery of mandible prognathism and asymmetry. Preoperative Surgical Treatment Objective(STO) using SMV was performed to 12 patients, who visited to Seoul National University Bundang Hospital with chief complaints like mandible prognathism or asymmetry from Dec 2007 to Feb 2009. Surgical splint was made of stone model repositioned according to STO using SMV. We estimate the change in skeletal midline and the stability of occlusion through superposition between preoperative and postoperative SMV. It was effective on the amount of mandible movement and the correction of mandibular asymmetry, while the facial asymmetry involved with maxilla was excluded. It was concluded that STO using SMV is available and predictable method for not only the setback of prognathic mandible but also the correction of mandible asymmetry accurately.

• The Journal of Advanced Prosthodontics
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• v.3 no.2
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• pp.76-80
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• 2011

PURPOSE. Implant stability quotient (ISQ) values have been supposed to predict implant stability. However, the relationship between ISQ values and bone-to-implant contact ratio (BIC%) which is one of the predictors of implant stability is still unclear. The aim of the present study was to evaluate initial ISQ values in relation to BIC% using rabbit model. MATERIALS AND METHODS. Four New Zealand white rabbits received a total of 16 implants in their tibia. Immediately after implant placement ISQ values were assessed. The measurements were repeated at the time of sacrifice of the rabbits after 4 weeks. Peri-implant bone regeneration was assessed histomorphometrically by measuring BIC% and bone volume to total volume values (bone volume %). The relationships between ISQ values and the histomorphometric output were assessed, and then, the osseointegration prediction model via the initial ISQ values was processed. RESULTS. Initial ISQ values showed significant correlation with the BIC%. The bone volume % did not show any significant association with the ISQ values. CONCLUSION. In the limitation of this study, resonance frequency analysis is a useful clinical method to predict the BIC% values and examine the implant stability.

• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.2
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• pp.161-171
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• 2006

Endosseous implants have restored normal function and dental health to many patients. When implants were introduced as an effective treatment modality, their efficacy was limited by the amount of available bone. Today, various grafting procedures can surgically create bone width and volume. Implants can be placed in more ideal locations for successful prosthetic reconstruction. The use of autogenous bone grafts represents the "gold standard" for bone augmentation procedures. Either intraoral or extraoral sites may be considered for donor sites. Alveolar ridge augmentation using autogenous bone block, can be done during implant placement or staged with implant placement, after bone graft healing. In the staged technique, a better implant positioning and the use of wide diameter implants are possible. Alveolar ridge augmentation using autogenous block graft is a predictable way of treatment, for the atrophic alveolar ridge before implant placement. The cases presented in this article clinically demonstrate the efficacy of using a autogenous block graft in generating effective new bone fill for dental implant placement.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.551-562
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• 2016

There are interferences between the teeth to be moved and the clear aligner made from setup. These interferences generate forces which move teeth to the desired position. However, these can cause incomplete tooth capture of clear aligner. When these interferences exceed the acceptable deformation of aligner, unwanted intrusion of teeth to be moved occurs. When correction of rotation or tipping of teeth is attempted, intrusion prevails before rotation or tipping. However, clear aligner can induce labiolingual tipping or intrusion easily. To achieve preliminary alignment including control of rotation and tipping, NiTi archwires with fixed appliance can be used first, and then clear aligner can be used for finishing in mild Class I maloccusion cases. For this purpose, clear aligner can be made using a digital setup and 3D printing. To move teeth using a clear aligner, tooth capture is critical. To improve tooth capture of clear aligners, slingshot or vertical elastics can be used. These were discussed with illustrations.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.320-325
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• 2012

Purpose: The purpose of this study was to evaluate the stability of the total setback of maxilla. It also discussed the surgical considerations of the procedure. Methods: The study consisted of 15 patients (mean age, $25.53{\pm}5.71$) who were treated with total setback Le Fort I osteotomy (with or without additional posterior maxillary impaction). The cone beam computed tomography was obtained before surgery (T0), 3~4 days after surgery (T1), and 6 months after surgery (T2). The surgical changes as well as the relapse of reference points in relation to the reference planes were statistically analyzed. Results: The mean maxillary setback was 2.35 mm. There were posterior movements of A-point ($0.73{\pm}0.83$ mm) during T2-T1. An opening of the nasolabial angle (mean $12.58^{\circ}$) was noted. Conclusion: Total maxillary setback allows combining satisfactory functional and cosmetic results for a number of carefully selected patients.

• The korean journal of orthodontics
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• v.13 no.1
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• pp.73-82
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• 1983

The author studied on the dental arch widths and lengths and height of palates at 3 groups of dentition: mixed dentition, early permanent dentition, young adult, having normal occlusion and dentition. The models of the 336 maxillary and mandibular case, made from alginate-base hydrocolloid impressions were measured and analyzed statistically. The result as follows; 1. The upper intercanine width increased between the mixed dentition group and early permanent dentition group but there was no change in the young adult group in both sexes. The lower intercanine width increased between the mixed dentition group and early permanent dention group in the male. 2. The upper and lower 1st bimolar width increased slightly with age in the male but there was no change in the female. 3, The sex difference found in this study was one of absolute size, the female being slightly smaller than the male in the early permanent dentition group and young adult. 4. The arch length had no notable sexual differences and decreased between the mixed dentition group and early permanent dentition group. There was no change in the arch length in the young adult. 5. The height of palate increased gradually with age.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.735-743
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• 1993

In orthodontic field, although lots of new materials have been developed and many mechanics intro duced, we can face the case patient cooperation still remain a problem to solve. So, factors related to the compliance of 254 adolescent orthodontic patients using intraoral elastic or extraoral orthopedic appliances were under investigation. The study subjects were 11 to 18 years old and from 5 exclusive orthodontitc clinics in seoul. The subjects were asked to fill a questionnaire and compliances were evaluated by their assigned orthodontists. The questionnaire was consisted of 63 questions, and they represent 13 factors-7 psychological & 6 nonpsychological fators. The collected data were analyzed using ANOVA test between the compliance group and the factors. 1. The compliances were evenly distributed in both sex and age groups. 2. As a whole, it was found that the Attitude towards appliances ffactor affected the degree of compliance. 3. Besides that, in younger(11-12) age group, Pain and discomfort associated with treatment factor was also found to be related to the degree of compliance. 4. On the contrary, in older(16-18) age group, the degree of compliance was influenced by the factor of Achievement motivation, Role expectation, parental relationship.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.619-631
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• 1993

Tooth movement by segment is one of the means which are frequently used in daily orthodontic practice. When we retract or intrude a tooth or teeth, we should recognize the center of resistance of the certain tooth or teeth. There have been many studies about the center of resistance of a single tooth, not so much was about the tooth-segment. At the present study the center of resistance of the maxillary anterior segment is experimentally investigated by using laser reflection technique and metal splints on the human dry skull. The variables of intrusive force magnitude are divided into two groups, 50g and 100g groups. The results were as follows ; 1. The center of resistance of the maxillary anterior segment composed of the central and lateral incisors was at the mesial portion of canine crown at the coronal level. 2. The center of resistance of the maxillary anterior segment composed of the central and lateral incisors and canines is between the canine and the 1st premolar crowns at the coronal level.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.661-669
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• 1993

The purpose of this study was to investigate a possibility of chronic or intermittent bacteremia in patients undergoing orthodontic treatment with fixed orthodontic appliance. Orthodontic patients who had been injured by orthodontic appliances and/or suffered from gingivitis were selected. They had not taken any antibiotics for 1 month. The number of subjects were 21 including 7 males and 14 females. Blood samples of the subjects were cultured and, IgG, IgA and IgM levels in the serum were quantified. The author found following results. 1. No bacterial growth was found in 7-day culture of all the samples. 2. The immunoglobulin levels in serum were confined in normal range. 3. This study could not deny the possibility of transient bacteremia episode undergoing orthodontic treatment.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.543-564
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• 1993

A cephalometric study was undertaken to reveal significant differences of craniofacial morphology of operated congenital cleft lip and palate subjects and control subjects. The material for this study consisted of 73 subjects with operated congenital cleft lip and palate subjects(53 males, 20 females) and 110 control subjects (7 males, 34 females) ranging from 3 to 14 years old. Each group was divided into four age groups (3-5, 6-8, 9-11, 12-14 year) and analyzed by Cohen's method and Burstone's method. The following conclusions were obtained ; 1. In Wit's appraisal, there was no difference the cleft lip and palate subjects and the control subjects. 2. In the cleft lip and palate subjects, they had smaller and more retrusive maxilla than the control subjects in both sexes. 3. In the cleft lip and palate subjects, they had more retrusive mandible than the control subjects in both sexes. 4. In the cleft lip and palate subjects, they had more concave profile than the control subjects.