순구개열환자의 치아 수와 형태 이상에 관한 연구

백승학,양원식 대한치과교정학회 2001 대한치과교정학회지 Vol.31 No.1

순구개열은 선천성 악안면 기형 중에서 발생률이 가장 높은 질환이며 특히 동양인에게 높은 빈도로 발생된다. 그리고 순구개열에서는 파열부 조직의 선천적 상실과 파열부 봉합 수술후 형성된 반흔에 의한 상악골의 열성장과 상악 악궁의 협착, 코의 형태 이상 등과 함께 치아의 수, 크기와 형태 및 맹출 이상도 높은 빈도로 동반된다. 따라서 저자들은 순구개열 환자의 치아 수, 형태 및 맹출 이상에 관한 임상적 자료를 수집,평가하여 진단과 치료계획 수립시 기초자료로 사용하기 위하여 본 연구를 시행하였다. 1988년 3월부터 1999년 2월까지 서울대학교병원 교정과에 내원하였던 순구개열환자 241명의 초진시 교정 chart와 cleft chart, orthopantomogram, intraoral x-ray film, 진단용 모형을 사용하여 순구개열군 별로 매복치, 과잉치, 결손치, 왜소치의 유무와 위치를 조사하여 다음과 같은 결론을 얻었다. 1.결손치는 비교적 높은 발생빈도 (56.8%) 를 보였으며, 치아별 발생빈도는 상악 측절치와 상악 제2소구치에서 높은 수치를 보였다. 순구개열 군별 결손치의 발생율은 구순구개열군과 구순치조열군이 구순열군과 구개열군에 비해 높게 나타났다. 그리고 구순열군, 구순치조열군, 구순구개열군 내에서 모두 양측성이 편측성에 비해 결손치의 발생율이 높게 나타났다. 2.과잉치는 11.2 %에서 발견되었으며, 장소별 발생빈도는 영구치열과 유치열에서 상악 측절치와 상악 견치 사이에서 가장 많이 발생되었다. 순구개열 군별 과잉치의 발생율은 구순열군, 구순치조열군, 구개열군, 구순구개열군의 순이었다. 3.매복치는 18.3% 에서 관찰되었으며, 치아별 발생빈도는 상악 측절치와 상악 견치에서 그 발생 빈도가 가장 높았다. 순구개열 군별 매복치 발생율은 구순열군, 구순구개열군, 구개열군, 구순치조열군의 순이었다. 4.왜소치는 15.8%에서 발견되었으며, 치아별 발생빈도는 상악 측절치와 상악 견치에서 가장 많았다 순구개열군별 왜소치의 발생율은 구순치조열군, 구순구개열, 구순열의 순이었다. 그리고 구개열군에서는 왜소치가 발견되지 않았다. Cleft lip and/or palate (CLP) is one of the most common congenital craniofacial anomalies and occurs more frequently in Asian people. Dental abnormalities in number, size, shape, and eruption of teeth are frequently associated with CLP. The purposes of this study were to investigate the effects of CLP on number, size, shape and eruption of teeth and to provide basic clinical data for diagnosis and treatment of the CLP patients. With the orthodontic and cleft charts, diagnostic models, orthopantomograms and intraoral x-ray films from 241 CLP patients who visited Dept. of Orthodontics, Seoul National University Dental Hospital, we evaluated the frequency of congenital missing teeth, supernumerary teeth, impacted teeth, and microdontia. The results were as follows ; 1.Frequency of congenital missing was relatively high up to 56.8 %. Congenital missing occurred frequently in the maxillary lateral incisor and the maxillary second premolar. Among the CLP types, frequencies of congenital missing in cleft lip and palate group and cleft lip and alveolus group were higher than those of cleft lip group and cleft palate group. And bilateral cleft showed higher frequencies than unilateral ones. 2.Supernumerary tooth was shown in 11.2 % of CLP patients. It occurred frequently in the area between the maxillary lateral incisors and the maxillary canine. Among the CLP types, cleft lip group showed relatively most highest frequency. 3.Impaction was shown in 18.3 % of CLP patients. It occurred most frequently in the maxillary lateral incisor and the maxillary canine than other teeth. Among the CLP types, cleft lip group and cleft lip and palate group showed most highest frequencies. 4.Microdontia was shown in 15.8 % of CLP patients. It occurred the most frequently in the maxillary lateral incisors and maxillary canines. Among the CLP types, cleft lip and alveolus group and cleft lip and palate group showed relatively higher frequencies, There was no microdontia in cleft palate group.

골격형 Ⅲ급 전치개교와 과개교합에 대한 비교고찰 및 MEAW에 의한 치험예

백승학,양원식 대한치과교정학회 1991 대한치과교정학회지 Vol.21 No.3

The purpose of this report is to review vertical dysplasia such as open bite or deep bite in skeletal Class Ⅲ malocclusion and their treatment modality and to present two cases treated with MEAW. The results obtained were as follows. A. Open bite case 1. The treatment time was 3 year 8 months. 2. Upper and lower incisors showed extrusion and especially lower anterior alveolar process showed remodelling. 3. The mesially inclined upper and lower molars were uprighted and especially lower first molars showed extrusion that means remodelling of alveolar bone. 4. Normal over bite and over jet were established. 5. Mandible showed slight clockwise rotation. 6. Maxilla showed slight downward bending of ANS part. 7. Upper lip showed downward drop and lower lip showed retraction and touch between upper and lower lip was established. 8. Tongue posture of post-treatment was more raised than pretreatment. B. Deep bite case 1. The treatment time was 1 year 8 months. 2. Upper incisors showed intrusion and labioversion and lower incisors showed slight intrusion and linguoversion. 3. The lower molars showed distal uprighting and intrusion and upper molars showed mesial movement and extrusion. 4. Normal over bite and over jet were established. 5. Maxilla did not show downward movement. 6. Mandible showed slight clockwise rotation. 7. Lower lip showed retraction and downward drop and upper lip showed downward drop.

한국인 성인의 악안면 연조직의 심미적 안모형태분석에 관한 연구

백승학,양원식 대한치과교정학회 1991 대한치과교정학회지 Vol.21 No.1

This study was designed to analyze morphological characteristics of Korean young adults, norms and standard deviation of variables, sexual differences, correlationship between each area of face and correlationship between hard tissue and soft tissue. The primary sample consisted of 45 males and 57 females who were early and middle twenties and had acceptable profile, no history of previous orthodontic treatment, absence of remarkably large overjet and overbite, full complement of permanent teeth, Class Ⅰ skeletal and dental relationships and good vertical facial proportions. Their cephalograms were analyzed morphologically with a computer morphometrics. Then the final sample- 25 males and 38 females -were selected within 1 S.D. of E-line, ANB, P/A facial height ratio, Interincisal angle, L1 to A-Pog, ODI and APDI. The results of the study were as follows: 1.In the form and proportion of facial skeleton there were no significant differences between males and females, but in the size males were larger than females. 2.The dental protrusion patterns had no significant sexual difference and no significant correlationship between protrusion of upper lip and inclination of upper incisor. But mentolabial angle had positively correlated with interincisal angle and negatively with inclination of upper and lower incisor. 3.In the relationship between nose and soft-tissue profile, males were larger than females in nasal length, height and angular measurements. 4.In analysis of soft-tissue profile, males were larger than females in the length and thickness. In the angular measurements and proportion of soft-tissue profile, there were no significant differences between males and females.

토끼 태자에 형성시킨 구순열상의 치유과정에서 수종 성장인자 분포에 관한 연구

백승학,양원식 대한치과교정학회 1997 대한치과교정학회지 Vol.27 No.5

성체의 상처 치유과정 중 반흔조직 형성에 수종의 성장인자가 관련이 있는 것으로 보고되고 있으나, 태자의 피부상처가 반흔형성없이 치유되는 기전에 관한 성장인자의 역할은 아직 알려져 있지 않다. 따라서 본 연구의 목적은 토끼 태자의 상처 치유과정에서 반흔조직의 형성과 관련이 있는 수종 성장인자의 분포를 조사하기 위한 것이다. 뉴질랜드산 흰 토끼를 임신 3기의 중반인 24일째에 자궁절개술을 시행하고 태자에 인위적으로 구순열상을 만든후, 봉합한 군(봉합군)과 봉합하지 않은 군(비봉합군), 정상대조군(sham operated control group)으로 나누고 이들을 각각 수술후 1, 2, 3, 5, 7일째에 희생시켜 상처치유에 대한 육안관찰 소견과 H&F염색소견 및 TGF-β1, TGF-β2, PDGF, bFGF의 면역조직화학적 염색 소견을 관찰하여 다음과 같은 결론을 얻었다. 1. 봉합군과 비봉합군에서 전기간동안 염증반응과 반흔조직의 형성 그리고 신생 혈관의 형성 증가는 없었다. 2. 비봉합군의 재상피화가 봉합군에 비해 다소 느렸다. 3. bFGF는 정상대조군, 봉합군과 비봉합군에서 차이가 없었다. 4. PDGF는 봉합군과 비봉합군에서 1, 2일군에서 증가하였다가 그후 감소하여 정상대조군과 차이가 없었다. 5. TGF-β는 봉합군과 비봉합군에서 1, 2일군에서 약간 증가하였다가 그후 감소하여 정상대조군과 차이가 없었다. TGF-β1에 비하여 TGF-β2의 검출양이 많았다. Recently several growth factors such as TGF-β1, TGF-β2, PDGF, bFGF are known to play an important role in scar formation following adult tissue injury. But there is little known about the role of growth factors in fetal tissue healing without scar formation. Therefore the purpose of this study is to investigate the distribution of growth factors which are involved with scar formation in the artificially created cleft lip wound healing of fetuses. The author had undergone hysterotomy and created cleft lip-like defects on fetuses of New Zealand White Rabbit in mid-third trimester(24 days). Fetuses were divided into 3 groups(the repaired group, the unrepaired group and the sham-operated control group). At 1, 2, 3, 5, 7days after procedure, the repaired, the unrepaired and the control groups were obtained by Caeserean section. After documenting the viability of fetuses, fetuses were photographed to compare size and facial morphology and sectioned for histological examination by H & E stain and spatial and temporal deposition of TGF-β1, TGF-β2, PDGF, bFGF by immunohistochemical method. The findings are summarized as follows 1. There were lack of inflammation and scar formation and neovascularity in the repaired and the unrepaired group during experimental periods. 2. The reepithelialization of the unrepaired group was slower than that of repaired group. 3. There were no differences of distribution of bFGF in the control, the repaired and the unrepaired group. 4. PDGF was increased at post-op. first and second day and decreased after post-op. third day. Eventually, there were no differences in the control, the repaired and the unrepaired group. 5. TGF-β1 and TGF-β2 were slightly increased at post-op. first and second day and decreased after post-op. third day. Eventually there were no differences in the control, the repaired and the unrepaired group. And TGF-β2 is more densely stained than TGF-β1.

Rat의 복강에 삽입한 Fluorouracil-Polyglycolic acid 제형의 Fluorouracil 용출에 관한 연구

노승무,정경수,오정연,김진향,양준묵,강대영,송규상,최정목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 忠南大學校 癌共同硏究所 1998 癌共同硏究所 硏究誌 Vol.2 No.1

A common form of relapse in adenocarcinoma of the stomach is intraperitoneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adcnocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.

Rat의 복강에 삽입한 Filorouracil-Polyglycolic acid제형의 Fluorouracil용출에 관한 연구

노승무,정경수,오정연,김진향,양준묵,강대영,송규상,최정목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

A common form of relapse in adenocarcinoma of the stomach is intraperitioneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adenocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.

위암환자의 복강내에 투여한 Mitomycin C-Carbon Particle의 Mitomycin 용출에 관한 연구

노승무,조영훈,정경수,오정연,김진향,양준묵,강대영,송규상,조준식,최선웅,이진호,민병무,김용백,김창식,박근성,인현빈,정현용,김학용 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

Locoregional recurrence is the most common type of recurrence in surgical operation of gastric adenocarcinoma, and peritoneal dissemination is one of the most difficult problems in advanced gastric adenocarcinoma treatment. Because the peritoneal cavity is the most common site of the first recurrence after gastric cancer resection, intraperitoneal chemotherpy seems a logical choice for cancer chemotherapy. The Mitomycin C(MMC) adsorbed by the activated charcoal particles(CH) is relatively released when the drug concentration surrounding the carbon particles becomes low in the peritoneum of the peritoneal cavity. For the intraperitoneal chemotherapy on the advanced gastric adenocarcnoma, mitomycin C adsorbed on activated carbon particles was administered in the peritoneal cavity just before abdominal wall closure. The closed drainage tubes were inserted in the peritoneal cavity and clamped for tuo hours after completion of operation. MMC concentrations were serially measured in peritoneal fluid, plasma and urine at 2hour, 48 hour, 72 hour and 168 hour following its administration in order to study the efficacy of the MMC-CH as a drug delivery system. There were minimal toxicities in born marrow, liver, and gastrointestinal system after intraperitoneal MMC-CH administration. The data of this study suggested that MMC-CH may have a somewhat more beneficial effect than surgery alone when administered in optimal dose and schedules, but the MMC concentration of the peritoneal fluid was not sufficient to eradicate remnant cancer cells, and effective duration of maintenance was only below 24 hours in the peritoneal fluid and plasma.

생체분해성 망막압정을 이용한 망막고정에 대한 실험적 연구

김용백,민병무,김창식,박근성,김승영,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

Biodegradable retinal fixation devices obtain mechnical fixation of the retina with desirable chorioretinal scarring and with the potential for local, sustained release of antimetabolites and steroids to inhibit proliferative vitreoretinopathy. We manufactured a biodegradable retinal tack with barb that was designed in order to prevent intrusion from implantation of retinal tacks. This study was carried to evaluate the efficacy for retinal fixation and the capability for sustained release of drugs with a newly designed biodegradable retinal tack Biodegradable retinal tacks were made of polymers of glycolic acids and were designed with barbs in a shape to prevent the disinsertion. Biodegradale retinal tacks are divided into 3 parts, a conical portion that is inserted into the sclera, a cylinder portion that remains in the vitreous, and a neck portion between the pin and the cylinder. The tapered conical end was manufactured to allow easy insertion through the retina and choroid into the sclera. A cylinder portion was manufactured with a tapered angle that fixes firmly into the orifice of 19 gauge spinal needle. A neck portion, 0.4 mm in diameter, was designed to prevent disinsertion from following implantation of retinal tack. The applicator was a 19 gauge spinal needle and its orifice was prepared to 15°angle to accept the tapered cylinder portion of the retinal tack. The retinal tacks, secured in the needles, were passed through the formed vitreous and inserted into the retina, choroid, and sclera and were released by pushing the internal needle, usually within 2-3mm of the medullary ray of the posterior rabbit retina A retinal tack was placed in each of 8 pigmented rabbit eyes. Slit-lamp biomicroscopy, indirect ophthalmoscopy and fundus photography were performed periodically from 1 day to 8 weeks after surgery. Eight eyes were enucleated and studied by light microscopy at 8 weeks. Biomicroscopic evaluation of the animals revealed edemas adjacent to the retinal surfaces immediately after insertion of the biodegradable retinal tacks in all the animals. These edemas disappeared after 1 week. The first noticeable change in the size of retinal tacks was shown after 2weeks. The size of the retinal tacks gradually got smaller, decreasing to about one-half at 4 weeks and about one-third at 8 weeks. All retinal tacks remained in inserted places without any movement for an 8 week period. On light microscopy, epiretinal proliferations were seen to extend into the vitreous cavity. Cellular capsules that lined the inner aspect of the scleral defect caused by tack insertion were found. However the adjacent retina had a normal cytologic appearance and architecture in all specimens. We manufactured a biodegradable retinal tack that is designed to prevent intrusion from implantation of retinal tacks. All biodegradable retinal tacks reduce in size with time, but no retinal tacks extruded from the inserted place. The newly designed biodegradable retinal tack can be used for retinal fixation and may be used as a vehicle for the introduction of pharmacologic agents to prevent the cellular events that promote proliferative vitreoretinopathy.

토끼 태자에 형성시킨 구순열상의 치유과정에서 세포외기질 분포에 관한 연구

양원식,백승학 대한치과교정학회 1998 대한치과교정학회지 Vol.28 No.1

태아와 성체의 상처치유과정에서 다른 점으로는 태아 상처가 염증반응과 반흔조직의 생성이 없이 신속히 치유됨을 들수 있다. 태자상처의 비반흔성 치유와 세포외기질의 역할을 연관지어 해석하려는 노력이 진행중에 있으나, 각 실험 동물종간의 차이 및 세포외기질 구성요소의 다양성 등 많은 변수가 아직 미결의 과제로 남아 있다. 본 연구의 목적은 토끼 태자의 상처 치유과정에서 반흔조직의 형성과 관련이 있는 세포외 기질의 주요성분인 교원질 Ⅰ,Ⅲ,Ⅳ,Ⅴ형, fibronectin, laminin의 시기적 출현 및 분포양상을 조사하기 위한 것이다. 뉴질랜드산 흰 토끼를 임신 3기의 중반인 24일 째에 자궁절개술을 시행하고 태자에 인위적으로 구순열상을 만든 후, 봉합한 군(봉합군)과 봉합하지 않은 군(비봉합군), 정상대조군(sham operation group)으로 나누고 이들을 각각 수술 후 1,2,3,5,7일째에 희생시켜 상처치유에 대한 육안관찰 소견과 H&F염색소견 및 교원질Ⅰ,Ⅲ,Ⅳ,Ⅴ형, fibronectin, laminin의 면역조직화학적 염색 소견을 관찰하여 다음과 같은 결론을 얻었다. 1. 봉합군과 비봉합군에서 전기간동안 염증반응은 없었다. 2. 비봉합군의 재상피화가 봉합군에 비해 다소 느렸다. 3. 교원질 Ⅰ,Ⅲ,Ⅴ형은 봉합군과 비봉합군에서 2일군까지는 발견되지 않았고 3일군 이후 존재하였으나 염색정도가 인접정상조직이나 정상대조군에 비하여 증가하지 않았다. 4. 상피 기저막에서 교원질 Ⅳ형의 염색소견은 봉합군과 비봉합군에서 3일군이 다소 증가하였으나 그후 감소하여 인접정상조직이나 정상조직이나 정상대조군과 차이가 없었고, laminin의 염색소견은 봉합군과 비봉합군에서 5일군이후 발견되었고 염색정도의 증감없이 7일군까지 유지되었고 인접정상조직이나 정상대조군과 차이가 없었다. 5. 혈관내피세포 기저막에서 laminin과 교원질 Ⅳ형의 염색소견은 인접정상조직이나 정상대조군에 비해서 증가하지 않았다. 6. Fibronectin은 봉합군과 비봉합군에서 fibrin clot과 창상 기저부 및 창상연을 따라 3일군까지 염색소견이 증가하였다가 그후 감소하여 인접정상조직이나 정상대조군과 차이가 없었다. Adult wound healing is accompanied with inflammation and eventual scar formation, whereas fetal wounds heal rapidly by mesenchymal prpliferation without significant inflammatory cell participation and with minimal or no scar formation. The cellular mechanisms underlying these differing forms of wound healing are unknown but the extracellular matrix, through its effects on cell function, may play a key role. Therefore the purpose of this study is to investigate the spatial and temporal deposition of several component of extracellular matrix, which are known to be involved with scar formation, in the artificially created cleft lip wound healing of fetuses. The author had undergone hysterotomy and created cleft lip-like defects on fetuses of New Zealand White Rabbit in mid-third trimester(24 days). Fetuses were divided into the repaired group, the unrepaired group and the sham-operated control group. At 1,2,3,5,7 days after procedure, fetuses were obtained by Caeserean section. After documenting the viability of fetuses, they were photographed to compare size and facial morphology and sectioned for histological examination by H&E stain and spatial and temporal deposition of collagen typeⅠ,Ⅲ,Ⅳ,Ⅴand fibronectin, laminin by immunohistochemical method. The findings are summarized as follows 1. There were lack of inflammation in the repaired and the unrepaired group during experimental periods. 2. The reepithelialization of the unrepaired group was slower than that of the repaired group. 3. Collagen Ⅰ,Ⅲ,Ⅴ were found from post-op. third day. There were no difference of distribution in the control, the repaired and the unrepaired group. Collagen typesⅠ,Ⅲ,Ⅴ were present in all groups with restoration of the normal collagen pattern in the fetus. This implies that lack of scarring in fetal wounds is due to the difference of collagen organization pattern within wound and not simply lack of collagen formation. 4. Collagen Ⅳ was slightly increased at post-op. third day and decreased after post-op. fifth day. Eventually there were no difference in control, the repaired and the unrepaired group. Laminin was found at post-op. fifth day and maintained staining density until post-op. seventh day. There were no differences in the control, the repaired and the unrepaired group. According to staining of laminin and collagen typeⅣ in epithelial basement membrane, formation of epithelial basement membrane was not completed until reepithelialization was finished. 5. According to staining of laminin and collagen typeⅣ, there were no increase of neovascularity in the repaired and the unrepaired group. 6. Fibronectin was increased until post-op. third day at fibrin clot, wound base and margin and decreased after post-op. fifth day. Eventually, there were no differences in the control, the repaired and the unrepaired group. So it implies fibronectin plays a role as provisional matrix for fetal wound healing.

하악 제1대구치 맹출 장애의 교정치료

김태경,백승학 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.3

하악 제1대구치의 맹출 장애는 매우 드문 편으로 맹출로에 물리적인 장애가 있거나 맹출 과정의 결함으로 인해 생긴다. 하악 제1대구치의 맹춘 장애가 있으면 그 원인을 살펴 정확한 치료계획을 세워야 하는데 무엇보다도 조기진단과 조기 치료가 중요하다. 일차미맹출(primary retertion)된 하악 제1대구치를 치개 절개와 forced eruption을 통해 치료하여 치료결과가 양호하고 성공적으로 유지된 증례를 살펴보고자 한다. Eruptive disturbance of the permanent lower first molar is an uncommon condition caused by physical barriers on the eruption path or failure of the eruptive mechanism. Once eruptive disturbance of the permanent lower first molar is diagnosed, treatment should be started as soon as possible to establish a normal eruption pathway and to avoid any detrimental effects on the developing occlusion. A case of primary retention of the mandibular first permanent molar treated with operculectomy and forced eruption which showed good treatment results and stability is described.