The effect of chlorhexidine on reduction of viable organisms in aerosol produced by ultrasonic scaler / 대한치주과학회지

PURPOSE: The aerosol generated by ultrasonic scaler can contain bacteria or virus which can penetrate into body through respiratory systems of dentists, dental hygienist or patients. The aim of this study is to evaluate the effect of chlorhexidine digluconate as preoperative mouthrinse or lavage for ultrasonic scaler on the reduction of viable organisms in aerosol produced during periodontal treatment using ultrasonic scaler. METHODS: 30 patients with moderate chronic periodontitis were included and divided into 3 groups: Control (no preoperative mouthrinse and tap water as lavage), CHG (preoperative mouthrinse with 0.1% chlorhexidine digluconate and tap water as lavage), CHL (no reoperative mouthrinse and 0.1% chlorhexidine digluconate as lavage). Each patient received scaling or subgingival curettage for 30 min. In CHG group, mouthrinse with chlorhexidine digluconate was performed for 1 min. before treatment. Before, during and after scaling or subgingival curettage, air sampling was performed for 7 min. each (1000 L/7 min.) with trypticase-soy agar plate. Agar plates were incubated in 37degrees C aerobically. The numbers of colony-forming units (CFU) were counted and compared. RESULTS: The numbers of CFUs of the samples obtained during treatment were 97+/-14.0 in control, 73.1+/-14.9 in CHG group and 44.5+/-9.0 in CHL group. The difference among the 3 groups was determined to be statistically significant (one-way ANOVA with Bonferroni's correction, p-value: 0.0003). In contrast, the numbers of CFU of samples obtained before and after treatment were not significantly different among the groups. CONCLUSIONS: Chlorhexidine digluconate used as preoperative mouthrinse or lavage for ultrasonic scaler can reduce the microorganisms in aerosol produced during periodontal treatment using ultrasonic scaler. Less number of microorganisms were detected when chlorhexidine was used as lavage for ultrasonic scaler.

Maxillary sinus floor augmentation with anorganic bovine bone: Histologic evaluation in humans / 대한치주과학회지

PURPOSE: The aim of this report is to investigate the efficacy of anorganic bovine bone xenograft(Bio-Oss(R) ) at maxillary sinus floor augmentation. MATERIALS AND METHODS: Two male patients who missed maxillary posterior teeth were included. They were performed maxillary sinus floor augmentation using anorganic bovine bone xenograft(Bio-Oss(R) ). After 10 or 13 months, the regenerated tissues were harvested using trephine drills with 2 or 4mm diameter and non-decalcified specimens were made. The specimens were examined histologically and histomorphometrically to investigate graft resorption and new bone formation. RESULTS: Newly formed bone was in contact with Bio-Oss(R) particles directly without any gap between the bone and the particles. The proportions of newly formed bone were 23.4~25.3% in patient 1(Pt.1) and 28.8% in patient 2(Pt.2). And the proportions of remained Bio-Oss(R) were 29.7~30.2% in Pt.1 and 29.2% in Pt.2. The fixtures installed at augmented area showed good stability and the augmented bone height was maintained well. CONCLUSION: Anorganic bovine bone xenograft(Bio-Oss(R) ) has high osteoconductivity and helps new bone formation, so that it can be used in maxillary sinus floor augmentation.