Purpose: This study sought to compare the elemental constitution, morphological characteristics, particle size distribution, biocompatibility, and mineralization potential of Ortho MTA (OMTA) and ProRoot MTA (PMTA). Materials and Methods: OMTA and PMTA were compared using energy-dispersive spectrometry, particle size analysis, and scanning electron microscopy. The biocompatibility and mineralization-related gene expression (osteonectin and osteopontin) of both MTAs were also compared using methylthiazol tetrazolium assay and reverse transcription-polymerization chain reaction analysis, respectively. The results were analyzed by Kruskal-Wallis test with Bonferroni correction. P-value of <0.05 was considered significant. Result: The morphology of OMTA powders was similar to that of PMTA. The constituent elements of both MTAs were calcium, silicon, and aluminum. The mean particle sizes of OMTA and PMTA were 4.60 and 3.34 mm, respectively. Both MTAs had equally favorable in vitro biocompatibility and affected the messenger RNA expression of osteonectin and osteopontin. Conclusion: Within the limitations of this study, OMTA could be a promising biomaterial in clinical endodontics.

Purpose: Autogenous tooth bone graft is proven to be efficient. We evaluated the bone healing effect and clinical capabilities of autogenous tooth bone materials as a scaffold when growth factor is used together with this material. Materials and Methods: Subjects were those who needed implant placement and bone graft because of missing tooth or alveolar bone defect and who kept their autogenous tooth or needed extraction of other tooth. Group I included autogenous tooth bone graft with growth factor, whereas Group II had only autogenous tooth bone graft. We investigated the bone healing state through computed tomography taken just before surgery and 3 to 4 months after surgery to evaluate the effectiveness of bone graft. Group I had 9 patients, whereas Group II had 5 patients. We compared the pre- and post-operative increase of the Hounsfield unit and bone height by analyzing the computed tomography images. Result: Sinus bone grafts numbered 8 cases, and vertical ridge augmentation was performed together with 3 cases of these. Vertical ridge augmentation was performed in 2 cases, and horizontal ridge augmentation in 1 case alone. Socket graft was done in 3 cases. The post-operative mean value of the Hounsfield unit was 960 in Group I and 836.7 in Group II, but the increase was almost similar, i.e., 636.9 in Group I and 634.7 in Group II on the average. Increase of bone height was 7.6 mm in Group I and 11.1 mm in Group II on the average. This difference was attributable to the fact that most of the cases were sinus bone graft in Group II. Conclusion: In this study, we suggest the possibility of autogenous tooth bone graft materials as a scaffold besides their bone healing ability.

Purpose: The inferior alveolar nerve (IAN) can be damaged as a result of minor oral surgical procedure such as third molar extraction or implant placement. Repair of the injured IAN involves difficulty of access, and research studies are limited to elucidating the process of regeneration by surgical methods. This study sought to establish the rabbit animal model to apply polymeric membrane functionalized with nerve growth factor after a crush lesion for the evaluation of nerve regeneration using the electrophysiologic method. Materials and Methods: The IAN of 2 adult male New Zealand white rabbits (4 nerves) were exposed bilaterally, and crush injury rendered by jeweler's forceps was applied. Nerve conduction velocity was examined electrophysiologically using electromyography before, after, and 4 weeks after the crush injury. To evaluate the regeneration, the pattern of action potential of IAN was recorded, and the characteristics of neurons were histologically observed. Result: After the crush injury, afferent activity decreased in the injured group. Electromyography could not be recorded after four weeks because tissues surrounding the injured nerve collapsed. Decrease in the mean number of axons was observed in the injured part with membrane. Conclusion: Despite the limited result, the present animal model study may provide a possible way to research on the methods of enhancing the recovery of nerve injuries in clinical situations. For clinically widespread acceptance, however, it should gain more consecutive and scientific evidences.

Purpose: The purpose of this study was to evaluate the survival and success rates of Korean Osstem implants US II Plus, GS II following loading period. Materials and Methods: Dental records were obtained in total 201 patients who were treated with Korean Osstem implants US II Plus, GS II on both maxillary and mandibular anterior and posterior areas in six different clinics for 2 years from January 2007 to December 2008. Total 430 implants were evaluated clinically and radiographically using predefined success criteria prospectively and following results were obtained. Result: US II Plus, GS II implants showed high survival rates of more than 99% and high success rates more than 90% independent of loading period. As a result of cross analysis to evaluate clinical significance between implant loading period and success rate, the P-value of US II Plus was 0.10 (P>0.05), and the P-value of GS II was 0.17 (P>0.05), which showed no statistical significance. Bone quality, smoking, and edentulous state are factors that can affect the survival and success rates following differently loaded implants, but did not significantly affect in this study. Conclusion: These results suggest that selection of loading period of Korean Osstem implants US II Plus, GS II would be done carefully considering implant install area, the quality alveolar bone, the state of edentulous ridge and experience of operator, though they showed clinically good results on both maxillary and mandibular anterior and posterior areas.

Purpose: The purpose of this study was to assess the effects of lip anteroposterior position based on esthetic line on the perceived attractiveness. Materials and Methods: We selected a 20s female standard lateral photograph which was within average range of cephalometric analysis, modified lips anteroposterior position based on esthetic line into 5 pictures. This study investigated and compared the preference of facial profile among the groups; male : female and dental relevance: non-dental relevance. Total 255 judges (male : female=138 : 117, relevant : non-relevant=159 : 96) who were 20s to 30s were asked to rate these photographs based in lip attractiveness using visual analogue scale (VAS). Result: All groups had similarity the average of VAS of moved backward lips 2 mm were highest and moved forward lips 4 mm were lowest. Comparing between male group and female group, there were significant differences in all pictures except for original which was not modified. In the dental groups, moved forward lips 2 mm had significant difference and the average in dental relevant group were lower than non-relevant group in lip protrusion. Conclusion: The preference about lip protrusion was similar irrespective of dental knowledge or gender. All groups preferred retrusion of lips to protrusion of lips. In female group, they had higher the average of VAS. In relevant group, they disliked protrusion rather than retrusion of lips significantly.

Synovial chondromatosis (SC) is a rare, benign disease found in metaplastic cartilaginous nodules within the synovial membrane. The etiology of SC is not well-known, but it may be associated with trauma, chronic abnormal loading, or inflammatory joint disease. It is often found in knee, elbow, ankle, and shoulder joint but rarely in the temporomandibular joint (TMJ) area. SC of TMJ frequently appears in middle age and more often in females. Clinical symptoms include periarticular swelling, pain, crepitus, and limitation of joint motion. The most common feature is a radiographic finding of loose bodies in the joint. Irregularity of joint space and condylar head is also observed. Treatment involves the surgical removal of synovium and loose bodies. The prognosis is good, with low postsurgical recurrence rate. Functional improvement of the joint and pain relief are noted in many patients. Malignant transformation of SC has not been recorded. In this study, we report a 54-year-old female patient who experienced discomfort on the right TMJ with SC on the area but made a satisfactory recovery after surgery.

The proper management of mandibular fractures involves reduction, rigid fixation, and immobilization to allow bone healing. Nonunion or malunion at the fractured sites is a well-known complication of fracture when the treatments are inappropriate. We present a case of left mandibular fracture due to shrapnel during the Korean War. The patients did not receive appropriate treatment at that time, so nonunion and malunion developed. Sixty years after the accident, mandibular osteomyelitis on the fracture site developed due to dental-origin inflammation. The treatment was based on relatively conservative care, such as saucerization and administration of antibiotics. There was no complication during the short-term follow-up. We present the case with literature review.