Seong-Yong Moon

Comparison of Titanium and Biodegradable Miniplates for Fixation of Mandibular Fractures

PURPOSE The purpose of the present study was to compare the use of biodegradable miniplates and titanium miniplates for the fixation of mandibular fractures. PATIENTS AND METHODS BioSorb FX biodegradable plates and screws and titanium miniplates were used in 91 patients (65 males and 26 females; age range 11 to 69 years) for the treatment of mandibular fractures. The clinical and radiographic findings were recorded at 1, 3, 6, and 12 months after surgery. RESULTS The overall complication rate was 4.41%. In the biodegradable plate group, infection occurred in 2 cases (4.26%) and was resolved by incision and drainage and antibiotics. In the titanium plate group, infection occurred in 1 case and plate fracture in 1 case (4.56%). The fractured plate was removed, and a new titanium miniplate was applied using a trocar. The infection was resolved with antibiotics. No adverse tissue reactions, malocclusions, or malunions occurred during the observation period. CONCLUSIONS Our results have shown that the rate of morbidity is very low with the use of biodegradable plates and titanium plates, suggesting that biodegradable and titanium plates have the potential for successful use in the fixation of mandibular fractures.

Bisphosphonates-related osteonecrosis of the jaw in Korea: a preliminary report

Objectives Bisphosphonates (BP) are widely used in medicine for inhibiting bone resorption; however bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a major side effect of BP. To date, there have been no specific reports on the incidence of BRONJ among Koreans. This study investigated the preliminary results from a nationwide survey of BRONJ in the Departments of Oral and Maxillofacial Surgery (OMFS) at individual training hospitals. Materials and Methods A total of 15 OMFS departments (10 from dental schools, 4 from medical schools, and 1 from a dental hospital) participated in a multi-centric survey. This study assessed every BRONJ case diagnosed between January 2010 and December 2010. The patient age and BP type were evaluated. Results A total of 254 BRONJ cases were collected. The majority of BRONJ cases were associated with oral BP therapy, while 21.8% of the cases were associated with intravenous administration. Alendronate was the drug most frequently related to BRONJ (59.2% of cases), followed by risedronate (14.3%) and zolendronate (17.0%). The average age of BRONJ patients was 70.0±10.1 years, with a range of 38-88 years of age. With the number of BP patients in Korea reported to be around 600,000 in 2008, the estimated incidence of BRONJ is at least 0.04% or 1 per 2,300 BP patients. Conclusion The results suggest that the estimated incidence of BRONJ in Korea is higher than the incidence of other countries. Future prospective studies should be carried out to investigate the exact epidemiological characteristics of BRONJ in Korea.

Indirect compressive injury to the inferior alveolar nerve caused by dental implant placement.

a p Nerve-related complications have been reported frequently in dental implantation and the most frequent injury involves the inferior alveolar nerve (IAN). Previously published studies on nerve injury after dental implant surgery have focused on direct injury from surgical instruments or from the dental implant itself. However, an indirect compressive injury to the IAN has not been reported. The diameter of the drill is smaller than that of the dental implant. This size difference makes for a tight fit between the dental implant and the bone hole. In addition, it increases the initial stability of the dental implant. During placement of the implant, cancellous bone is inevitably compressed. If the IAN courses close to the dental implant and is not protected by the nerve canal, it can be injured.

Removal of a broken needle using three-dimensional computed tomography: a case report.

Inferior alveolar nerve block obtained maximum anesthetic effect using a small dose of local anesthetic agent, which also has low a complication incidence. Complications of an inferior alveolar nerve block include direct nerve damage, bleeding, trismus, temporary facial nerve palsy, and etc. Among them, the major iatrogenic complication is dental needle fracture. A fragment that disappears into the soft tissue would be hard to remove, giving rise to a legal problem. A 31-year-old woman was referred for the removal of a broken needle, following an inferior alveolar nerve block. Management involved the removal of the needle under local anesthesia with pre- and peri-operative computed tomography scans.

Effects of decortication in the treatment of bone defect around particulate dentin-coated implants: an experimental pilot study.

OBJECTIVES The purpose of this study was to evaluate the effects of decortication during bone grafting in defect areas surrounding particulate dentin-coated implants. STUDY DESIGN Six dogs were randomly assigned to 3 groups, and each group was further divided into 2 subgroups. The subgroups consisted of dogs that received particulate dentin-coated implants after 4 or 8 weeks. The defects were treated as follows: control group, unfilled defect; experimental group 1, defect filled with Tutoplast without decortication; experimental group 2, defect filled with Tutoplast with decortication. Histologic sections and histomorphometric analysis were obtained 4 and 8 weeks after surgery. RESULTS Compared to the 4-week subgroup, statistically significant new bone formation was observed in the 8-week subgroup. In the 4-week subgroup, the area of new bone formation was larger in the group that underwent cortical bone perforation with bone grafting; however, no significant difference was detected within the 8-week subgroup. CONCLUSION According to these results, decortication increases early bone formation after implant placement.

Vertical distraction osteogenesis using a titanium nitride–coated distractor

OBJECTIVES The purpose of this study was to examine the effect of using a titanium nitride (TiN)-coated vertical distractor on osseointegration after implantation. STUDY DESIGN Four adult mongrel dogs, weighing 9-10 kg, were used in this study. The lower premolars were extracted, and vertical distraction was performed after 10 weeks using 8 distraction devices (left, 4 titanium; right, 4 nitrified). A 7-day latency period was allowed before distraction began. The distraction device was activated at a rate of 0.5 mm twice a day for 5 days. After completing distraction, the device was removed after a consolidation period of 6 weeks and 24 implants were installed. The dogs were killed after 4 or 8 weeks. Histologic examinations were performed. RESULTS The implant success rate was 100% in all of the study groups. Direct bone contact was achieved, and there were no significant differences between the control and experimental groups in the implantation area. CONCLUSION The results suggested that the nitrified distraction device does not negatively affect osseointegration in the vertical distraction osteogenesis; therefore, it has the advantageous potential to substitute for the conventional distractor.

Ultra-thin Rigid diagnostic and therapeutic arthroscopy during arthrocentesis: Development and preliminary clinical findings

Arthroscopy is useful to detect early changes in the temporomandibular joint (TMJ).Despite great advances in arthroscopy, many arthroscopic surgeries have now been replaced by arthrocentesis. We propose a simple diagnostic and therapeutic method having operative rigid ultra-thin arthroscopy with 16 gauge needle size combined with arthrocentesis.