• Proceedings of the KOSOMBE Conference
• /
• v.1995 no.05
• /
• pp.95-100
• /
• 1995

This study investigated the effects of mechanical factors involved in several corneal refractive surgeries on the surgical outcomes. Then we proposed possible new techniques from the mechanical point of a view utilizing finite element method. The models studied are: circumferential keratetomy, combination of excimer laser photorefractive keratectomy and circumferential keratotomy for myopia treatment, arcuate keratotomy for astigmatism treatment. The cornea was assumed to be nonlinear elastic and almost incompressible material as the most soft tissue in the human body. In the circumferential keratotomy the effect of the incision location was investigated. The angle and location of the incision were varied to predict the surgical outcomes in the arcuate keratotomy. The finite element analysis results showed that the location of incision was a critical factor affecting the surgical outcomes in the circumferential keratotomy. In the combination of the excimer laser photorefractive keratectomy and circumferential keratotomy, it was predicted that the circumferential can increase or decrease the refractive power depending on the incision location or it can be used to adjust the overcorrection of undercorrection. In the arcuate keratotomy for astigmatism, the most diopter changes were predicted when the location and the angle of the incision were 3.0mm from the apex and $90^{\circ}$, respectively. In the arcuate keratotomy, the effects of an incision were studied within the incision area as well as outside the incision area. Also, the arcuate keratotomy with two incisions located on the opposite area of the cornea was also studied. As a conclusion, the finite element method is a useful technique in the area of corneal refractive surgeries to develop new techinques.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.14 no.3
• /
• pp.185-193
• /
• 1992

The calcifying odontogenic cyst was identified as a pathological entity by Gorlin & his associates in 1962. This lesion is one of the rarest and most disputable cysts in the oral region. The calcifying odontogenic cyst has variable clinical and radiological features. We review the previous literatures and report 2 cases of calcifying odontogenic cyst at Department of Oral and Maxillofacial Surgery, Kyung-Hee University. The 1st case was as follows. The patient vas 22 year old female. The past dental history revealed extraction of prolonged retained #73 tooth about 15days ago. She complained a painful swelling on the lower anterior teeth area. There were chin and vestibular swelling on the lower anterior teeth area, tenderness and missing of #33 tooth. The radiograph revealed well-demarcated unilocular radiolucency containing radiopaque calcific flecks around impacted #33 tooth. The clinical diagnosis was COC, so surgical enucleation was done. There was no recurrence and COC was confirmed by pathologist. The second case was as follows. The patient was 72 year old male. The past history revealed inactive tuberculosis, bronchial asthma and denture construction. The chief complaint was rapidly growing mass on the lower left anterior edentulous area. The clinical findings were chin swelling protruding mass with surface ulceration, fluctuation and a few bloody fluid in aspiration. The radiograph revealed well-demarcated radiolucency mimiking the residual cyst. The biopsy result was COC. The surgical excision was done, but the lesion was recurred 10 months later. The treatment was surgical excision with aggressive peripheral bone grinding and FTSG form groin area. There was no problem during the postoperative period.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1993.05a
• /
• pp.107-107
• /
• 1993

Tuberculous cervical lymphadenitis is one of the most common causes of neck mass in Korea. But the diagnostic confirmation is difficult and it's effective treatment modalities are still in controversy. Through a retrospective study of 32 cases of tuberculous cervical lymphadenitis treated with surgical treatment during recent 4 years, we have analyzed 5 subtypes of CT finding and surgical treatment modalities and received following results 1. The locations of lymphadenitis were posterior triangle(12 cases), submandibular area(9 cases), supraclavicular area(8 cases), submental area(2 cases), and parotid area(1 case). 2. Five subtypes of CT findings were observed : Homogeneous enhancement type(3 cases), peripheral rim enhancement type(6 cases), peripheral rim enhancement with perinodal fat obliteration type(12 cases), coalescent cold abscess type(8 cases), and mixed type(3 cases). 3. Surgical treatment modalities : Excision (13 cases), incision and drainage(9 cases), selective neck dissection(8 cases), and curettage(2 cases).

• Restorative Dentistry and Endodontics
• /
• v.43 no.2
• /
• pp.16.1-16.9
• /
• 2018

Objectives: Understanding the reason for an unsuccessful non-surgical endodontic treatment outcome, as well as the complex anatomy of the root canal system, is very important. This study examined the cross-sectional root canal structure of mandibular first molars confirmed to have failed non-surgical root canal treatment using digital images obtained during intentional replantation surgery, as well as the causative factors of the failed conventional endodontic treatments. Materials and Methods: This study evaluated 115 mandibular first molars. Digital photographic images of the resected surface were taken at the apical 3 mm level and examined. The discolored dentin area around the root canal was investigated by measuring the total surface area, the treated areas as determined by the endodontic filling material, and the discolored dentin area. Results: Forty 2-rooted teeth showed discolored root dentin in both the mesial and distal roots. Compared to the original filled area, significant expansion of root dentin discoloration was observed. Moreover, the mesial roots were significantly more discolored than the distal roots. Of the 115 molars, 92 had 2 roots. Among the mesial roots of the 2-rooted teeth, 95.7% of the roots had 2 canals and 79.4% had partial/complete isthmuses and/or accessory canals. Conclusions: Dentin discoloration that was not visible on periapical radiographs and cone-beam computed tomography was frequently found in mandibular first molars that failed endodontic treatment. The complex anatomy of the mesial roots of the mandibular first molars is another reason for the failure of conventional endodontic treatment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.38 no.1
• /
• pp.50-54
• /
• 2012

According to Luhr's classification, a fracture in the mandible with a width of less than 15-20 mm is considered to be an atrophic mandibular fracture and its incidence is very rare. Because of the reduced cross-sectional area and smaller contact area of the fractured ends as well as the poorly vascularized bony structure and delayed bone healing, an atrophic mandibular fracture is a great challenge for oral and maxillofacial surgeons. Surgeons tend to perform closed reduction, because open reduction is considered a non-life-saving surgery among elderly patients. Thus, most of them have limited experience in surgical management. According to recent reports, open reduction yields a good result, and the Association for Osteosynthesis (AO) group has recommended open reduction. This is a case report of our two experiences of open reduction and rigid fixation of atrophic mandibular fractures by the AO principle. Articles were also reviewed here.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.21 no.2
• /
• pp.215-219
• /
• 1999

This article discusses the diagnosis, anatomic consideration, and surgical management of masseter muscle hypertrophy. Surgical correction is advised for patients who have esthetic complaints. Esthetic improvement can be achieved by surgery and not by conservative treatment. Recently, the intraoral method, which leaves no scar on the face and minimizes the possibility of injury to the marginal branch of the facial nerve, has been supported by many surgeons. Patients who complained of marked swelling of unilateral or bilateral mandibular angle area and showed abnormal bony growth at the mandibular angle area and enlarged masseter muscle received mandibular angle shaving and excision of the inner layer of masseter muscle with intraoral approach. After operation, physiotherapy was done with EAST(eletrical acupuncture stimulation therapy) for encouraging the mouth opening and reducing the swelling. They showed early maximum mouth opening and reduction of swelling.

• Journal of International Society for Simulation Surgery
• /
• v.1 no.1
• /
• pp.7-12
• /
• 2014

Purpose Surgical correction of various occular problems which do not have visual problem in plastic surgical area is to normalize the appearance of the face by restoring the normal position of orbit and eyeball. With development of surgical technique, the orbit can be restored exactly in trauma patient and can be moved totally in hypertelorism, as an example of congenital disease. All these surgeries are based on the hypothesis that the position of oclular glove moves in the plane in a quantitatively predictable reationship to osseous orbit movement. However, no studies have critically evaluated between the change of periorbital soft tissue and the outcome of the surgical correction, because there is no method of objective, quantitave evaluation of the periorbital soft tissue. Method Author suggest the methodology for quantitative assessment of ocular and periocular fat changes using the manipulation of digital images of computed tomographic scan. Results The method was allowed to evaluate inter-dacryon distance, inter-centroid distance, movement of the medial orbital wall, movement of the lateral orbital wall, alteration of thickness of the lateral periorbital fat as indicator of movement of the orbital wall and orbit in the patient with congenital periorbital anomaly and postoperative periorbital surgery. The goal of surgical correction of various occular problems which do not have visual problem in plastic surgical area is to normalize the appearance of the face by restoring the normal position of orbit and eyeball. With development of surgical technique, the orbit can be restored exactly in trauma patient and can be moved totally in hypertelorism, as an example of congenital disease. All these sugeries are based on the hypothesis that the position of oclular glove moves in the plane in a quantitatively predictable relationship to osseous orbit movement. However, no studies have critically evaluated between the change of periorbital soft tissue and the outcome of the surgical correction, because there is no method of objective, quantitave evaluation of the periorbital soft tissue. In this report, author suggest the methodology for quantitative assessment of ocular and periocular fat changes using the manipulation of digital images of computed tomographic scan. Conclusion The method suggested is objective and accurate method in measurement of the orbital contents. It takes time and is not easy to do, however, this kind of measurement for fine structures will be more easily available in near future.

• Journal of Veterinary Clinics
• /
• v.16 no.1
• /
• pp.210-213
• /
• 1999

A 15 months old male pit bull terrier was shown submandibular swelling, which was extended from left submandibular area through mandibular symphysis to right submandibular area and toward around left neck. In history taking, recurrence of swelling was recorded after conservative surgical incision, drainage and dressing. Palpation revealed no pain and heating, partial flutuation and hardness. By paracentesis, it was showed blood-tinged tenacious exudate without bad-smelling. Left submandibular salivary gland was able to be movable freely and the size decreased to half of that of right submandibular salivary gland. It was diagnosed as cervical salivary mucocele. In operation, rostral portion of left sublingual salivary gland was observed to be damaged transversely, showed black color and leaked saliva. Submandibular gland and rostral portion of sublingual salivary gland were resected, after ligation of ducts of submandibular and sublingual salivary glands. At 15 days postoperation, serosanguineous exudate from operation wound was dramatically decreased and stable granulation tissue mass at this area was first palpated. At 39 days after operation, outline of left and right mandibular was appeared normal and skin tenderness of mandibular area was equal to that of the other body wall.

• Advances in pediatric surgery
• /
• v.4 no.1
• /
• pp.74-78
• /
• 1998

Early recognition and surgical treatment of Hirschsprung's disease prevents serious mortality and morbidity from enterocolitis and obstruction. Usually this disease is characterized by a single aganglionic segment of the colon extending distally to the anal margin. In surgical treatment, the surgeon performs a frozen section biopsy to confirm whether there are ganglion cells. If there are intervening ganglionic sites in aganglionic bowel, there may be confusion in diagnosis and treatment. The authors experienced one case of total colonic aganglionosis with skip area. A transverse loop colostomy was performed on a 7 day-old male baby with colon perforation due to Hirschsprung's disease. But intestinal obstruction persisted and required two more operations to find the true nature of the disease. There were aganglionic segments from the anal margin to the terminal ileum 3.7cm proximal to the ileocecal valve. The entire transverse colon and appendix were normally ganglionated.

• Journal of Chest Surgery
• /
• v.15 no.2
• /
• pp.222-229
• /
• 1982

The aneurysmal dilatation of ascending aorta with the aortic regurgitation presents typical surgical problems. Over the years, various surgical procedures had been used for the management of the dilated segment of sending aorta and the aortic regurgitation. The surgical technique Is still in the state of evolution. The one method is the super coronary replacement of the ascending aorta with vascular graft and replacement of the aortic valve with preservation of the coronary ostia as advocated by Miller and his colleague at Stanford University, so called conventional technique". The other is the replacement of aortic valve and the dilated segment of the ascending aorta using a composite graft and transplantation of the coronary ostia as described by Bentall and DeBono in 1968. The controversy appears to evolve around 3 technical problems. One is bleeding from the grafted area. Two is later development of the aneurysmal dilatation of the subcoronary aortic wall when non-composite graft is employed. Three is a management of the coronary arteries. The purpose of this article is to present our experience with 7 cases of annuloaortic ectasia in whom both of these surgical techniques at that employed and to review some of the problems that encountered during the management of these patients .