Retrospective clinical study of an implant with a sandblasted, large-grit, acid-etched surface and internal connection: analysis of short-term success rate and marginal bone loss / 대한악안면성형재건외과학회지

BACKGROUND: The purpose of this retrospective study was to evaluate the clinical utility of an implant with a sandblasted, large-grit, acid-etched (SLA) surface and internal connection. METHODS: Six patients who received dental implants in the Department of Oral and Maxillofacial Surgery, Chonnam National University Dental Hospital, were analyzed by factors influencing the success rate and marginal bone loss. Factors included patient’s age, sex, implant installation site, whether bone graft was done, type of bone graft materials, approaching method if sinus lift was done, and the size of the fixture. In addition, the marginal bone loss was analyzed by using a radiograph. RESULTS: All implants were successful, and the cumulative survival rate was 100 %. Average marginal bone loss of 6 months after the installation was 0.52 mm and 20 months after the functional loading was 1.06 mm. Total marginal bone resorption was 1.58 mm on average. There was no statistically significant difference in mesial and distal marginal bone loss. CONCLUSIONS: The short-term clinical success rate of the implant with an SLA surface and internal connection was satisfactory. Moreover, the marginal bone loss was also consistent with the implant success criteria.

Evaluation of clinical outcomes of implants placed into the maxillary sinus with a perforated sinus membrane: a retrospective study / 대한악안면성형재건외과학회지

BACKGROUND: The aim of this study was to evaluate the clinical outcomes of implants that were placed within the maxillary sinus that has a perforated sinus membrane by the lateral window approach. METHODS: We examined the medical records of the patients who had implants placed within the maxillary sinus that has a perforated sinus membrane by the lateral approach at the Department of Oral and Maxillofacial Surgery of Chonnam National University Dental Hospital from January 2009 to December 2015. There were 41 patients (male:female = 28:13). The mean age of patients was 57.2 ± 7.2 years at the time of operation (range, 20–76 years). The mean follow-up duration was 2.1 years (range, 0.5–5 years) after implant placement. Regarding the method of sinus elevation, only the lateral approach was included in this study. RESULTS: Ninety-nine implants were placed in 41 patients whose sinus membranes were perforated during lateral approach. The perforated sinus membranes were repaired with a resorbable collagen membrane. Simultaneous implant placements with sinus bone grafting were performed in 37 patients, whereas delayed placements were done in four patients. The average residual bone height was 3.4 ± 2.0 mm in cases of simultaneous implant placement and 0.6 ± 0.9 mm in cases of delayed placement. Maxillary bone graft with implant placement, performed on the patients with a perforated maxillary sinus membrane did not fail, and the cumulative implant survival rate was 100%. CONCLUSIONS: In patients with perforations of the sinus mucosa, sinus elevation and implant placement are possible regardless of the location and size of membrane perforation. Repair using resorbable collagen membrane is a predictable and reliable technique.

Logistic regression analysis of factors affecting survival of permanent second molars in Korean adults / 대한구강보건학회지

OBJECTIVES: The purpose of this study was to analyze the factors affecting the survival of permanent second molars in Korean adults using logistic regression analysis. METHODS: This National survey was conducted in 2006 and was performed in 3 stages comprising stratified sampling, age, sex, and region. This study included 15,777 persons, aged 2-95 years. The raw data was analyzed using SPSS software v12.0 and the relationship between the 9 variables and the tooth survival rate was analyzed by frequency and cross-tabulation. Logistic regression analysis using the functional weightage of the age, sex, regions of the Korean population was also performed. Entry was at level of 5%, while removal was at a 10% level during logistic regression analysis. The nine variables used for analysis were age, socio-economic level, monthly family income, sex, frequency of toothbrushing per day, diabetes, educational level, smoking, and frequency of snack intake per day. RESULTS & CONCLUSIONS: The most significant explanatory variables, in increasing order of significance, were age, socioeconomic status, and diabetes. As age increased by 10 years, the survival rate of second molars decreased at a slow rate 7.5% to 9.5%. The survival rate of the second molar of an individual engaged in activities, such as farming, stock breeding, and fishing decreased from 64.4% to 78.8% as compared to people at high positions in various companies and in society.

Effect of an Education Program on Violence in the Emergency Department

PURPOSE: In response to a growing threat of violence in hospitals, we examined a specific educational effort to reduce emergency department (ED) violence in the shortterm. METHODS: Cross-sectional prospective surveys were conducted at Chosun University Hospital Emergency Center during a baseline period from May 26 to Jul. 9. 2003, and during a post-education period from Aug. 7 to Sep. 20. 2003. Questions addressed the degree of violence, the reason for the violence, demographic information about the perpetrator of the violence, the outbreak time of the violence and the response of emergency personnel. RESULTS: After an education program on violence, the rate of violent events in the ED was decreased by 23.5%. A notable change was that ED workers handled the violence more positively during the post-education period by isolating or restraining the aggressor. Almost all of the violence was caused by males, particularly those in their third or fourth decade. The violence occurred mostly on the night shift. Of the violence, 52.4% was caused by the patient while 34.8% was caused by the patient's guardian. The leading causes of violence were drunkenness and delays in laboratory tests and treatment. Verbal abuse and threats were the most concern forms of violence. CONCLUSION: Violent events are frequent in the ED. Education programs may reduce the number of events at least temporarily.

Effects of Interferon-gamma on collagen and fibronectin synthesis in primary cultured periodontal ligament cells / 대한치과교정학회지

Interferon-gamma has been suggested as a cytokine of connective tissue stabilizer. In addition, it has also been demonstrated that this cytokine inhibited bone remodeling activities of the bone derived cells. In order to illuminate the effects of this cytokine in orthodontic force induced bone remodeling, it was administered to primary cultured periodontal ligament cells which have been known to have some osteoblast like characteristics. Interferon-gamma slightly decreased [3H]thymidine incorporation rate without a significant change in the total cellular DNA content up to 1000 U/ml, which meant these doses were not cytotoxic to the cell. Total protein synthesis was not influenced by various concentration of interferon-gamma whether it was determined by the [3H]proline incorporation rate or by the Lowry smethod. The effect of interferon-gamma on the individual protein was, however, differential, ie, it increased [3H]proline incorporation into the noncollagenous protein marginally, while it decreased [3H]proline incorporation into the collagen, so that it caused dose-dependent suppression of the relative collagen synthesis. On the contrary, the fibronectin synthesis determined by the ELISA was increased by 1000 U/ml of interferon-gamma. The differential effects of the interferon-gamma on the collagen and fibronectin synthesis exhibited not only their protein level but also the steady state mRNA level. Interferon-gamma decreased steady state level of alpha1(I) procollagen mRNA significantly, while showing no significant changes in the fibronectin mRNA level. In addition to this, it was also found that indomethacin did not affect on the interferon-gamma induced collagen decrease in this cell, which meant prostaglandins were not involved in the process of interferon-gamma induced collagen decrease. So it can be concluded that the incubation of periodontal ligament cells with 1000 U/ml of interferon-gamma for 24 hr showed differential effects on the type I collagen and fibronectin gene expression. The decrease in relative collagen synthesis in the protein level was related with decrease in the steady state level of mRNA, while the increase in the fibronectin synthesis in the protein level was not correlated with the mRNA level.