• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권1호
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• pp.32-45
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• 1995

This study was intended to evaluate condyle position and the relationship of condyle position change and post surgical relapse following the sagittal split ramus osteotomy for mandible setback in 25 patients by paired t-test and multiple regression analysis. We used oblique transcranial and cephalometric radiographs taken before operation, immediate after operation, and at least 6 months post operatively. 1. In oblique transcranial view, posterior joint space was decreased immediate after operation and increased 6 months after operation. To compare the measurement before and 6 months after operation, there was no statistically significant change in over all joint spaces(P>0.05). 2. The joint spaces changed under the 0.2mm were 30%, 0.2mm to 1.0mm were 60.7%, above 1.0mm were 9.3%. This result reveals that condyle position was relatively reproduced to pre-operative state. 3. Statistically, the amount of mandible set back didn't influence the post operative relapse(P>0.05). 4. Statistically, the amount of mandible set back didn't influence the condylar displacement(P>0.05), and the amount of joint space change didn't influence the post operative relapse.(P>0.05) The changes in joint space is in the standard tracing error or within the adaptive capacity of the individual, it was too small to influence the stability of surgery.

• 대한치과교정학회지
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• 제50권5호
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• pp.304-313
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• 2020

Objective: The aim of this study was to evaluate the stability of bimaxillary surgery involving bilateral intraoral vertical ramus osteotomy performed with or without presurgical miniscrew-assisted rapid palatal expansion (MARPE) in adult patients with skeletal Class III malocclusion. Methods: A total of 40 adult patients with skeletal Class III malocclusion were retrospectively divided into two groups (n = 20 each) according to the use of MARPE for the correction of transverse maxillomandibular discrepancy during presurgical orthodontic treatment. Serial lateral cephalograms and dental casts were analyzed until 6 months after surgery. Results: Before presurgical orthodontic treatment, there was no significant differences in terms of sex and age between groups. However, the difference of approximately 3.1 mm in the maxillomandibular intermolar width was statistically significant (p < 0.001). Two days after surgery, the mandible had moved backward and upward without any significant intergroup difference. Six months after surgery, the maxillary intercanine (2.7 ± 2.1 mm), interpremolar (3.6 ± 2.4 mm), and intermolar (2.0 ± 1.3 mm) arch widths were significantly increased (p < 0.001) relative to the values before presurgical orthodontic treatment in the MARPE group; these widths were maintained or decreased in the control group. However, there was no significant difference in surgical changes and the postsurgical stability between the two groups. No significant correlations existed between the amount of maxillary expansion and postsurgical mandibular movement. Conclusions: MARPE is useful for stable and nonsurgical expansion of the maxilla in adult patients with skeletal Class III malocclusion who are scheduled for bimaxillary surgery.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제38권3호
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• pp.139-144
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• 2012

This study was performed in order to evaluate the occurrence of temporomandibular joint disorder after surgical correction of skeletal class II malocclusion. Materials and Methods: This study included 21 patients who underwent orthognathic surgery for the correction of dentofacial deformities by a single surgeon at Mokdong Hospital, Ewha Womans University from 2000 to 2010. They underwent bilateral sagittal split ramus osteotomy for the treatment of undesirable mandibular advancement. The temporomandibular disorder (TMD) symptoms prior to surgery were recorded and the radiographic evaluation (panorama, bone scan, and magnetic resonance imaging [MRI]) of the post-surgery temporomandibular joint (TMJ) were assessed in order to evaluate condylar resorption, remodeling and disc displacement. The minimum follow-up period, including orthodontic treatment, was 12 months. Orthognathic procedures included 1-jaw surgery (n=8 patients) and 2-jaw surgery (n=13 patients). The monocortical plate was used for bilateral sagittal split ramus osteotomy fixation. Results: Among class II malocclusion patients with TMD symptom, clicking improved in 29.1%, and maximum mouth opening increased from $34.5{\pm}2.1$ mm to $37.2{\pm}3.5$ mm. The differences were not statistically significant, however. Radiographic changes in bone scan improved slightly based on the report by radiologist but not in TMJ dynamic MRI. Conclusion: No particular improvements were found in patients with joint sound only. Patients with limitation of mouth opening showed an increase in the degree of opening, but the difference was not statistically significant (P>0.05).

• 대한치과교정학회지
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• 제46권5호
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• pp.301-309
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• 2016

Objective: The aim of this study was to evaluate the skeletal and dental changes after intraoral vertical ramus osteotomy (IVRO) with and without presurgical orthodontics by using cone-beam computed tomography (CBCT). Methods: This retrospective cohort study included 24 patients (mean age, 22.1 years) with skeletal Class III malocclusion who underwent bimaxillary surgery with IVRO. The patients were divided into the preorthodontic orthognathic surgery (POGS) group (n = 12) and conventional surgery (CS) group (n = 12). CBCT images acquired preoperatively, 1 month after surgery, and 1 year after surgery were analyzed to compare the intergroup differences in postoperative three-dimensional movements of the maxillary and mandibular landmarks and the changes in lateral cephalometric variables. Results: Baseline demographics (sex and age) were similar between the two groups (6 men and 6 women in each group). During the postsurgical period, the POGS group showed more significant upward movement of the mandible (p < 0.05) than did the CS group. Neither group showed significant transverse movement of any of the skeletal landmarks. Moreover, none of the dental and skeletal variables showed significant intergroup differences 1 year after surgery. Conclusions: Compared with CS, POGS with IVRO resulted in significantly different postsurgical skeletal movement in the mandible. Although both groups showed similar skeletal and dental outcomes at 1 year after surgery, upward movement of the mandible during the postsurgical period should be considered to ensure a more reliable outcome after POGS.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.19.1-19.6
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• 2018

Background: Calcium pyrophosphate dihydrate deposition disease (CPDD) is a rare disease in the temporomandibular joint (TMJ) space. It forms a calcified crystal mass and induces a limitation of joint movement. Case presentation: The calcified mass in our case was occupied in the left TMJ area and extended to the infratemporal and middle cranial fossa. For a complete excision of this mass, we performed a vertical ramus osteotomy and resected the mass around the mandibular condyle. The calcified mass in the infratemporal fossa was carefully excised, and the segmented mandible was anatomically repositioned. Scanning electronic microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDS) microanalysis was performed to evaluate the calcified mass. The result of SEM/EDS showed that the crystal mass was completely composed of calcium pyrophosphate dihydrate. This result strongly suggested that the calcified mass was CPDD in the TMJ area. Conclusions: CPDD in the TMJ is a rare disease and is difficult to differentially diagnose from other neoplasms. A histological examination and quantitative microanalysis are required to confirm the diagnosis. In our patient, CPDD in the TMJ was successfully removed via the extracorporeal approach. SEM/EDS microanalysis was used for the differential diagnosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권2호
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• pp.100-104
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• 2023

Autogenous bone grafts from the mandibular ramus are a known source of inadequate bone volume scenarios of the residual alveolar ridge. However, the conventional block-type harvesting technique cannot prevent bone marrow invasion, which can cause postoperative complications such as pain, swelling, and inferior alveolar nerve injury. This study aims to suggest a complication-free harvesting technique and present the results of bone grafting and donor sites. One patient received two dental implants with a complication-free harvesting technique that involves creation of ditching holes with a 1 mm round bur. Sagittal, coronal, and axial osteotomies produced grid-type cortical squares using a micro-saw and a round bur to confirm the cortical thickness. The grid-type cortical bone was harvested from the occlusal aspect, and the harvesting was extended through an additional osteotomy on the exposed and remaining cortical bone to prevent bone marrow invasion. The patient did not suffer postoperative severe pain, swelling, or numbness. After 15 months, the harvested site exhibited new cortical bone lining, and the grafted area had healed to a cortico-cancellous complex with functional loading of the implants. Our technique, grid-type cortical bone harvesting without bone marrow invasion, allowed application of autogenous bone without bone marrow invasion to achieve acceptable bone healing of the dental implants and to regenerate the harvested cortical bone.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.32.1-32.4
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• 2020

Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제37권
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• pp.36.1-36.7
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• 2015

Background: This study was performed to evaluate three-dimensional positional change of the condyle using three-dimensional computed tomography (3D-CT) following unilateral sagittal split ramus osteotomy (USSRO) in patients with mandibular prognathism. Methods: This study examined two patients exhibiting skeletal class III malocclusion with facial asymmetry who underwent USSRO for a mandibular setback. 3D-CT was performed before surgery, immediately after surgery, and 6 months postoperatively. After creating 3D-CT images by using the In-vivo $5^{TM}$ program, the axial plane, coronal plane, and sagittal plane were configured. Three-dimensional positional changes from each plane to the condyle, axial condylar head axis angle (AHA), axial condylar head position (AHP), frontal condylar head axis angle (FHA), frontal condylar head position (FHP), sagittal condylar head axis angle (SHA), and sagittal condylar head position (SHP) of the two patients were measured before surgery, immediately after surgery, and 6 months postoperatively. Results: In the first patient, medial rotation of the operated condyle in AHA and anterior rotation in SHA were observed. There were no significant changes after surgery in AHP, FHP, and SHP after surgery. In the second patient, medial rotation of the operated condyle in AHA and lateral rotation of the operated condyle in FHA were observed. There were no significant changes in AHP, FHP, and SHP postoperatively. This indicates that in USSRO, postoperative movement of the condylar head is insignificant; however, medial rotation of the condylar head is possible. Although three-dimensional changes were observed, these were not clinically significant. Conclusions: The results of this study suggest that although three-dimensional changes in condylar head position are observed in patients post SSRO, there are no significant changes that would clinically affect the patient.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제14권3호
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• pp.217-227
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• 1992

The purpose of this paper is to investigate changes in soft tissue in 22 patients treated by vertical ramus osteotomy and sagittal split ramus osteotomy for the correction of mandibular prognathism. 22 individuals, 12 males and 10 females, were selected from the patients with mandibular prognathism at the Department of Oral and Maxillofacial Surgery, Colledge of Dentistry, Kyung Hee University. Patient were analyzed with cephalogram taken 1 week before and at least 6 weeks after surgery under the same condition. Measurements were made constructed hard tissue and sop tissue points located on each before-and-after film tracing. Comparision were made of these figures to estimate the amount that the soft tissue followed the hard tissue structures in each surgical procedure : ratio of sop and hard tissue changes were formulated. The results were as follows. 1. The horizontal changes of Pogs and Bs as a ratio of the horizontal changes of Pog and B point were 1.02 and 1.16 respectively. 2. One millimeter of posterior changes at Pog resulted in 0.86mm of posterior change at Li and 0.09mm of posterior change at Ls. The greatest amount of sop tissue change occurred at Pogs, with substantially less posterior displacement at Bs, even less at Li and at least at Ls. 3. The ratio of LI to Li was 1:0.81 and the ratio of LI to Ls was not significant.(1 : 0.17) 4. The ULA(Cm-Sn-Ls) and the relative lower lip projection (LLP) was incnease4 but the relative upper lip projection (ULP) was slightly decreased 5. The angular change of the upper lip inclined angle (Ls-Sn/ANS-PNS) and lower lip inclined angle(Li-Pogs/Me-Go) expressed as a ratio of the posterior change of Pog were 0.57 and 0.20 respectively. 6. The ratio of the lower anterior facial height change of the soft tissue(Sn-Mes) to the hard tissue(ANS-Gn) were 0.78 and and the ratio of vertical height changes of the hard tissue and sop tissue to the posterior change of the Pog were 0.18 and 0.19 respectively. 7. The sop tissue angular change of facial convexity(G-Sn-Pogs) expressed as a ratio of the angular change of the hard tissue angle of facial convexity(N-A-Pog) was 1.24.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권1호
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• pp.87-108
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• 1996

본원에서 하악지시상골 절단술을 시행한 하악전돌증 환자 29명 (남자 12명, 여자 17명)을 대상으로 수술전, 수술후, 장기관찰기간동안 경조직과 연조직 변화를 관찰한 결과 다음과 같은 결과를 얻었다. 1. 술후 하악은 반시계방향회전하면서 후방이동 하였으며 장기관찰시 B와 Pog에서 1.23mm, 1.28mm의 재발을 보였다. 이는 술후의 하악이동에 따른 순수한 효과(Net effect)가 81.7%, 82.2% 라는 것을 의미하며 이러한 재발로 인하여 수술의 효과를 감소시킬 수 있다는 사실을 술전 치료계획에 포함시켜야 한다고 할 수 있다. 2. 하악 경조직의 수평변화에 대한 하악 연조직의 변화비율은 하순구에서 100%, 이부에서 99.1-102.1% 로 나타났으며 하순의 경우 72.7-93.7% 로 나타났으며 상순의 경우 하악 전치 이동량의 5.7% 정도 후방 이동하게 되지만 통계적 상관관계는 미약했으나. 수직적으로 8.3-9.6% 정도 유의한 하방이동양상을 보였다. 3. 술수 상순과 하순의 관계가 개선되어 심미선에 대하여 상순(Ls)은 상대적으로 동출하고 하순(Li)은 후방이동하였으며, 상순구가 얕아지고 하순구가 깊어졌으며, 비순각이 개선되어 전반적 안모가 개선되었으나 턱부위의 전돌은 수술후에도 약간 남아있었다. 4. 하악 연조직점을 종속변수로, 하악 경조직점을 독립변수로한 회귀분석에서 경조직 변화와 연조직 변화 사이의 높은 상관관계가 있다고 하여도 이를 정확하게 예측하기 어렵다는 것을 알 수 있었으며, 연조직 두께와 수평이동사이에는 통계적 유의성이 없었다.