Appropriate follow-up period for odontogenic keratocyst: a retrospective study / 대한악안면성형재건외과학회지

Purpose@#The aim of this study was to conduct epidemiologic investigations on the pattern of the lesion and differences between treatment modalities in terms of recurrence by reviewing follow-up records to form a basis for planning patient follow-up visits. @*Materials and methods@#In this retrospective, single-center cohort study, 266 patients diagnosed with odontogenic keratocyst between 1993 and 2013 were included. Medical records and radiographic images were analyzed for age distribution, occurrence site and size, treatment modalities, and recurrence. @*Results@#The average age at first diagnosis was 33.1 years, and the male to female ratio was 1.33:1.00. The highest rate of incidence was in the third decade followed by the fourth, second, and fifth decades. The incidence in the maxilla was 34%, and 66% in the mandible. Mandibular ramus was most commonly involved. Lesions between 3 and 6 crowns were the most common, and the rate of recurrence increased with size. Enucleation after decompression had higher rate of recurrence (35.8%) than enucleation (27.1%), but there was no statistical significance. @*Conclusion@#The recurrence of odontogenic kerotocyst (OKC) was significantly associated with large size, multilocular form, and surgical procedure. A 10-year follow-up period is recommended to determine any recurrence of OKC.

Three-dimensional evaluation of the correlation between lip canting and craniofacial planes / 대한치과교정학회지

Objective@#This study aimed to analyze the correlation of horizontal and sagittal planes used in two-dimensional diagnosis with lip canting by using threedimensional (3D) analysis. @*Methods@#Fifty-two patients (25 men, 27 women; average age: 24 years) undergoing treatment for dentofacial deformity were enrolled. Computed tomography images were acquired, and digital imaging and communication in medicine files were reconstructed into a 3D virtual model wherein horizontal and sagittal craniofacial planes were measured. Subsequently, the correlations of lip canting with these horizontal and sagittal planes were investigated. @*Results@#The mandibular symmetry plane, the occlusal plane, Camper’s plane, the mandibular plane, Broadbent’s plane, and the nasal axis plane were correlated with the amount of lip canting (Pearson’s correlation coefficients: 0.761, 0.648, 0.556, 0.526, 0.438, and 0.406, respectively). Planes associated with the lower part of the face showed the strongest correlations; the strength of the correlations decreased in the midfacial and cranial regions. None of the planes showed statistically significant differences between patients with clinical lip canting (> 3°) and those without prominent lip canting. @*Conclusions@#The findings of this study suggest that lip canting is strongly correlated with the mandibular symmetry plane, which includes menton deviation. This finding may have clinical implications with regard to the treatment of patients requiring correction of lip canting. Further studies are necessary for evaluating changes in lip canting after orthognathic surgery.

Comparison of three midsagittal planes for three-dimensional cone beam computed tomography head reorientation / 대한치과교정학회지

OBJECTIVE@#This study compared three prominent midsagittal planes (MSPs) to identify the MSP that best approximates the true symmetrical MSP.@*METHODS@#Forty-three patients (mean age, 23.0 ± 8.20 years) were grouped as follows: group 1 consisted of 10 patients with skeletal Class I and a menton (Me) deviation of < 2 mm; group 2, 11 patients with skeletal Class III and a Me deviation < 2 mm; group 3, nine patients with skeletal Class III and a Me deviation of 2 to less than 4 mm; and group 4, 13 patients with skeletal Class III and an Me deviation ≥ 4 mm. The candidate MSPs were established by three-dimensional (3D) cone beam computed tomography (CBCT) reorientation methods (RMs): (1) the MSP perpendicular to the Frankfort horizontal (FH) plane while passing through the crista galli and basion; (2) the MSP including the nasion, incisive foramen, and basion; (3) the MSP including the nasion, anterior nasal spine, and posterior nasal spine. The mean absolute distances (MADs) to the MSPs were calculated from the coordinates of 1,548 points on 129 CBCT images. The differences in the values of the 3D coordinates among RMs were compared.@*RESULTS@#The MADs of the three RMs showed significant differences (p < 0.05). Most of the differences in values of the coordinates were not significant among RMs.@*CONCLUSIONS@#Although the differences in distance among the three MSPs were minor, the MSP perpendicular to the FH plane while passing through the crista galli and basion best approximated the true symmetrical MSP.

Chin Profile Changes in Skeletal Class III Following Bimaxillary Surgery with or without Advancement Genioplasty

Purpose@#This study sought to identify differences in hard and soft tissue chin profile changes in skeletal Class III patients after bimaxillary surgery, with or without advancement genioplasty. @*Materials and Methods@#The retrospective study was conducted based on cephalometric analysis of skeletal and soft tissue variables. Lateral cephalograms taken at 3 different time points were utilized: pre-operation (T0), immediately post-operation (T1), and at least 6 months (11.0±2.6 months) post-operation (T2). The 2 groups were matched for sample size (n=20 each). Data were analyzed using independent t-tests with Bonferroni correction.Result: Group N (bimaxillary surgery alone) and Group G (bimaxillary surgery with an advancement genioplasty by horizontal sliding osteotomy) did not differ significantly in terms of demographic characteristics. The soft tissue chin thickness of Group G increased more after surgery, followed by a greater decrease during the postoperative period, and was eventually not significantly different from Group N at T2. On the other hand, the mentolabial sulcus depth of Group G (5.5±1.3 mm) was significantly greater than that of Group N (4.4±0.9 mm) (P=0.006) at T2. @*Conclusion@#Although Group G showed a statistically significantly greater decrease in soft tissue chin thickness during the postoperative period, there were no significant intergroup differences in the chin profile for at least 6 months after the surgery, except for the mentolabial sulcus depth, which was greater in Group G than in Group N.

Volume change pattern of decompression of mandibular odontogenic keratocyst / 대한악안면성형재건외과학회지

OBJECTIVES: This study was aimed to analyze the reducing pattern of decompression on mandibular odontogenic keratocyst and to determine the proper time for secondary enucleation. MATERIALS AND METHODS: Seventeen patients with OKC of the mandible were treated by decompression. Forty-five series of CT data were taken during decompression and measured by using InVivo software (Anatomage, San Jose, Calif) and were analyzed. RESULTS: The expected relative volume during decompression is calculated using the following formula: V(t) = V initial × exp.(at + 1/2bt 2) (t = duration after decompression (day)). There was no significant directional indicator in the rate of reduction between buccolingual and mesiodistal widths. CONCLUSION: The volume reduction rate gradually decreased, and 270 days were required for 50% volume reduction following decompression of OKC. The surgeon should be aware of this pattern to determine the timing for definitive enucleation. CLINICAL RELEVANCE: The volume reduction rate and pattern of decompression of the OKC can be predicted and clinicians should be considered when treating OKC via decompression.

Anatomical study of the location of the antilingula, lingula, and mandibular foramen for vertical ramus osteotomy / 대한악안면성형재건외과학회지

BACKGROUND: The purpose of this study was to identify the location of the antilingula, lingula, and mandibular foramen in Korean cadavers and to promote safe and accurate surgery without damage to the inferior alveolar neurovascular bundle (IANB) when performing a vertical ramus osteotomy (VRO). METHODS: This study was conducted on the dried mandibles of 20 adult cadavers. Digital calipers were used to measure the distances from the anatomical reference points (antilingula, lingula, and mandibular foramen). RESULT: The antilingula was located at the anterior 44% and superior 31% in the ramus. The lingula was located at the anterior 55% and superior 30% in the ramus. The mandibular foramen was located at the anterior 58% and superior 46% in the ramus. Regarding the positional relationship with the antilingula, the lingula was located 0.54 mm superior and 4.19 mm posterior, and the mandibular foramen was located 6.95 mm inferior and 4.98 mm posterior. The results suggested that in order to prevent damage to the IANB, osteotomy should be performed in the posterior region of ramus at least 29% of the total horizontal length of the ramus. CONCLUSION: Using only the antilingula as a reference point is not guaranteed to IANB injury. However, it is still important as a helpful reference point for the surgeon in the surgical field.

A Case of Pentastomiasis at the Left Maxilla Bone in a Patient with Thyroid Cancer

Pentastomiasis, a zoonotic parasite infection, is typically found in the respiratory tract and viscera of the host, including humans. Here, we report for the first time an extremely rare case of intraosseous pentastomiasis in the human maxilla suffering from medication related osteonecrosis of the jaw (MRONJ). A 55-year-old male had continuously visited the hospital for MRONJ which had primarily developed after bisphosphonate and anti-neoplastic administration for previous bone metastasis of medullary thyroid cancer. Pain, bone exposure, and pus discharge in the right mandible and left maxilla were seen. Osteolysis with maxillary cortical bone perforation at the left buccal vestibule, palate, nasal cavity, and maxillary sinus was observed by radiologic images. A biopsy was done at the left maxilla and through pathological evaluation, a parasite with features of pentastome was revealed within the necrotic bone tissue. Further history taking and laboratory evaluation was done. The parasite was suspected to be infected through maxillary open wounds caused by MRONJ. Awareness of intraosseous pentastomiasis should be emphasized not to be missed behind the MRONJ. Proper evaluation and interpretation for past medical history may lead to correct differential diagnosis and therapeutic intervention for parasite infections.

Complication rates in patients using absorbable collagen sponges in third molar extraction sockets: a retrospective study

OBJECTIVES: The purpose of this study is to retrospectively evaluate the postoperative complication rates for absorbable type-I collagen sponge (Ateloplug; Bioland) use in third molar extraction. MATERIALS AND METHODS: From January to August 2013, 2,697 total patients undergoing third molar extraction and type-I collagen sponge application in the Department of Oral and Maxillofacial Surgery at Yonsei University Dental Hospital (1,163 patients) and Dong-A University Hospital (1,534 patients) were evaluated in a retrospective study using their operation and medical records. RESULTS: A total of 3,869 third molars in 2,697 patients were extracted and the extraction sockets packed with type-I collagen sponges to prevent postoperative complications. As a result, the overall complication rate was 4.52%, with 3.00% experiencing surgical site infection (SSI), 1.14% showing alveolar osteitis, and 0.39% experiencing hematoma. Of the total number of complications, SSI accounted for more than a half at 66.29%. CONCLUSION: Compared to previous studies, this study showed a relatively low incidence of complications. The use of type-I collagen sponges is recommended for the prevention of complications after third molar extraction.

Orthognathic surgery and temporomandibular joint symptoms / 대한악안면성형재건외과학회지

The aim of this article is to review temporomandibular joint symptoms as well as the effects of orthognathic surgery(OGS) on temporomandibular joint(TMJ). The causes of temporomandibular joint disease(TMD) are multifactorial, and the symptoms of TMD manifest as a limited range of motion of mandible, pain in masticatory muscles and TMJ, Joint noise (clicking, popping, or crepitus), myofascial pain, and other functional limitations. Treatment must be started based on the proper diagnosis, and almost symptoms could be subsided by reversible options. Minimally invasive options and open arthroplasty are also available following reversible treatment when indicated. TMD manifesting in a variety of symptoms, also can apply abnormal stress to mandibular condyles and affect its growth pattern of mandible. Thus, adaptive developmental changes on mandibular condyles and post-developmental degenerative changes of mandibular condyles can create alteration on facial skeleton and occlusion. The changes of facial skeleton in DFD patients following OGS have an impact on TMJ, masticatory musculature, and surrounding soft tissues, and the changes of TMJ symptoms. Maxillofacial surgeons must remind that any surgical procedures involving mandibular osteotomy can directly affect TMJ symptoms, thus pre-existing TMJ symptoms and diagnoses should be considered prior to treatment planning and OGS.

Prenatal ultrasonographic diagnosis of cleft lip with or without cleft palate; pitfalls and considerations / 대한악안면성형재건외과학회지

Ultrasonographic examination is widely used for screening of abnormal findings on prenatal screening. Cleft lip with or without cleft palate of the fetus can also be screened by using ultrasonography. Presence of abnormal findings of the fetal lip or palate can be detected by the imaging professionals. However, such findings may not be familiar to oral and maxillofacial surgeons. Oral and maxillofacial surgeons can use ultrasonographic imaging of fetal cleft lip with or without cleft palate to provide information regarding treatment protocols and outcomes to the parent. Therefore, surgeons should also be able to identify the abnormal details from the images, in order to setup proper treatment planning after the birth of the fetus. We report two cases of cleft lip with or without cleft palate that the official readings of prenatal ultrasonography were inconsistent with the actual facial structure identified after birth. Also, critical and practical points in fetal ultrasonographic diagnosis are to be discussed.

Comparative analysis of the amount of postoperative drainage after intraoral vertical ramus osteotomy and sagittal split ramus osteotomy

OBJECTIVES: The purpose of this retrospective study was to compare the amount of postoperative drainage via closed suction drainage system after intraoral vertical ramus osteotomy (IVRO) and sagittal split ramus osteotomy (SSRO). MATERIALS AND METHODS: We planned a retrospective cohort study of 40 patients selected from a larger group who underwent orthognathic surgery from 2007 to 2013. Mean age (range) was 23.95 (16 to 35) years. Patients who underwent bilateral IVRO or SSRO were categorized into group I or group II, respectively, and each group consisted of 20 patients. Closed suction drainage system was inserted in mandibular osteotomy sites to decrease swelling and dead space, and records of drainage amount were collected. The data were compared and analyzed with independent t-test. RESULTS: The closed suction drainage system was removed at 32 hours postoperatively, and the amount of drainage was recorded every 8 hours. In group I, the mean amount of drainage was 79.42 mL in total, with 31.20 mL, 19.90 mL, 13.90 mL, 9.47 mL, and 4.95 mL measured at 0, 8, 16, 24, and 32 hours postoperatively, respectively. In group II, the mean total amount of drainage was 90.11 mL, with 30.25 mL, 25.75 mL, 19.70 mL, 8.50 mL, and 5.91 mL measured at 0, 8, 16, 24, and 32 hours postoperatively, respectively. Total amount of drainage from group I was less than group II, but there was no statistically significant difference between the two groups (P=0.338). There was a significant difference in drainage between group I and group II only at 16 hours postoperatively (P=0.029). CONCLUSION: IVRO and SSRO have different osteotomy design and different extent of medullary exposure; however, our results reveal that there is no remarkable difference in postoperative drainage of blood and exudate.

Cavernous sinus thrombosis caused by a dental infection: a case report

Cavernous sinus thrombosis not only presents with constitutional symptoms including fever, pain and swelling but also with specific findings such as proptosis, chemosis, periorbital swelling, and cranial nerve palsies. It is known to occur secondary to the spread of paranasal sinus infections in the nose, ethmoidal and sphenoidal sinuses. However, paranasal sinus infection of dental origin is rare. The following is a case of cavernous sinus thrombosis due to the spread of an abscess in the buccal and pterygomandibular spaces via buccal mucosal laceration.

Corrigendum: Cavernous sinus thrombosis caused by a dental infection: a case report

This correction is being published to correct the author's name.

Oral foregut cyst in the ventral tongue: a case report

An oral foregut cyst is a rare congenital choristoma lined by the respiratory and/or gastrointestinal epithelium. The exact etiology has not been fully identified, but it is thought to arise from misplaced primitive foregut. This lesion develops asymptomatically but sometimes causes difficulty in swallowing and pronunciation depending on its size. Thus, the first choice of treatment is surgical excision. Surgeons associated with head and neck pathology should include the oral foregut cyst in the differential diagnosis for ranula, dermoid cyst, thyroglossal duct cyst and lymphangioma in cases of pediatric head and neck lesions.

Partial Necrosis of the Mandibular Proximal Segment Following Transoral Vertical Ramus Osteotomy / 대한악안면성형재건외과학회지

Transoral vertical ramus osteotomy (TOVRO) procedure can result in a variety of complications. Complications commonly reported include extensive bleeding due to major blood vessel injury, unpredictable fracture, postoperative infection, neurosensory deficit related Inferior alveolar nerve, insufficient osteosynthesis, and temporomandibular joint problem. The authors describe a case of partial necrosis of the mandibular proximal segment following TOVRO, a rarely reported complication. A 37-year-old otherwise healthy woman underwent Lefort l osteotomy and TOVRO to correct mandibular prognathism. Postoperatively, she developed pain and swelling in the right submandibular region and was found to have a partial necrosis of proximal segment.

Repair of Unilateral Incomplete Lesser Form Cleft Lip

Repair of Unilateral Cleft Lip and Nose: Mulliken's Modification of Rotation Advancement