No abstract available.

The purpose of this study was to evaluate the success rate of Korean implant systems. A total of 245 implants were placed in 112 patients using different implant systems from February 1988 until June 2002. Data on implant systems, implant positions, surface treatments, guided bone regeneration procedure, marginal bone levels, and states of surrounding gingiva were collected. A follow-up evaluations were done after 1 year and 2 year of loading. Clinical parameters such as probing depth was evaluated at the last follow-up. The marginal bone loss after 1 year of loading was measured on periapical radiographs. Clinical comparisons were performed to evaluate implants loss in relation to the implant systems, implant positions, surface treatments, and guided bone regeneration procedure. There was no clinical difference of success rate in implant systems, implant positions, and surface treatments. Mean marginal bone resorption from the time of loading to 1 year follow-up was 0.31mm in Korean implant systems and 0.41mm in other implant systems. The cumulative survival rate of Korean implant systems and other implant systems at the 2-year of loading was 95.6% and 97.3% respectively. From these results, it was concluded that Korean implant systems could be successfully used in clinical dentistry.
Bone Regeneration ; Bone Resorption ; Dentistry ; Follow-Up Studies ; Gingiva ; Humans ; Retrospective Studies* ; Survival Rate

The purpose of this study was to evaluate the influence of accessibility to dental cervices of maxillary molars upon plaque control level of these areas. Fifthy-seven dental students with healthy gingiae participated in this study. Maxillary dental casts were fabricated for each participants. Using the casts, cervical accessibility was measured at the mid-palatal point of maxillary first and second molars. Cervical accessibility was defined as the perpendicular distance from the entrance of gingival sulcus to the imaginary line between the most protruded points of palatal gingiva and tooth surface, and classified into degree I(< or =0.5mm), II(>0.5mm, < or =1.0mm), III(>1.0mm, < or =1.5mm), and IV(>1.5mm). Plaque score was recorded as the distance from crest of gingival margin to the most coronal extent of plaque. Measurements of plaque score were repeated 3 times at 1-week intervals. After the baseline measurements, the participants began to use unitufted brushes on randomly assigned right or left side. Two weeks later, a session of plaque score records identical to the baseline measurements was started. The maxillary second molars showed higher cervical accessibility than the first molars(p<0.01), but the plaque scores of maxillary second molars were also higher than those of first molars(p<0.01). For the maxillary first molars, correlation between accessibility and plaque score was statistically significant, but such correlation was not found for the second molars. Use of unitufted brushes decreased the plaque score(p<0.01). Correlation between accessibility and the degree of plaque score improvement was not found. These findings suggest that cervical accessibility may influence the amount of plaque, and use of adjunctive oral hygiene devices may be helpful in maintaining optimal oral hygiene level at the areas of low cervical accessibility.
Gingiva ; Humans ; Molar* ; Oral Hygiene ; Students, Dental ; Tooth

Perforation of maxillary sinus is a common complication of implant placement in posterior maxilla. The purpose of this study was to evaluate the prognosis of sinus perforated implants placed in partially edentulous maxillae. Eighteen sinus perforated implants in 15 patients were examined for cumulative survival rate, radiographic preoperative bone level, and radiographic marginal bone level change. Twenty-two non-perforated implants in the same patients served as control. The results were as follows; 1. There was no statistically significant difference in cumulative survival rate between sinus perforated implants and non-perforated implants (P>0.05). 2. There was no statistically significant difference in the marginal bone level between sinus perforated implants and non-perforated implants (P>0.05). 3. There was no statistically significant difference in cumulative survival rate according to the preoperative bone level (P>0.05). These results suggests that perforation of maxillary sinus may not affect implant success in posterior maxillae.
Humans ; Maxilla ; Maxillary Sinus ; Prognosis ; Retrospective Studies* ; Survival Rate*

Dental plaque, a biofilm consisting of more than 500 different bacterial species, is an etiological agent of human periodontal disease. It is therefore important to characterize interactions among periodontopathic microorganisms in order to understand the microbial pathogenesis of periodontal disease. Previous data have suggested a synergistic effect of tow major periodontal pathogens Porphyromonas gingivalis and Tannerella forsythia in the periodontal lesion. In the present study, to better understand interaction between P. gingivalis and T. forsythia, the coaggregation activity between these bacteria was characterized. The coaggregation activity was observed by a direct visual assay by mixing equal amount (1 x 10(9)) of T. forsythia and P. gingivalis cells. It was found that the first aggregates began to appear after 5-10 min, and that the large aggregates completely settled within 1 h. Electron and epifluorescence microscopic studies confirmed cell-cell contact between two bacteria. The heat treatment of P. gingivalis completely blocked the activity, suggesting an involvement of a heat-labile component of P. gingivalis in the interaction. On the other hand, heat treatment of T. forsythia significantly increased the coaggregation activity; the aggregates began to appear immediately. The coaggregation activity was inhibited by addition of protease, however carbohydrates did not inhibit the activity, suggesting that coaggregation is a protein-protein interaction. The results of this study suggest that coaggregation between P. gingivalis and T. forsythia is a result of cell-cell physical contact, and that coaggregation is mediated by a heat-labile component of P. gingivalis and T. forsythia component that can be activated on heat treatment.
Bacteria ; Biofilms ; Carbohydrates ; Dental Plaque ; Forsythia* ; Hand ; Hot Temperature ; Humans ; Periodontal Diseases ; Porphyromonas gingivalis* ; Porphyromonas*

No abstract available.
Chlorhexidine* ; Guided Tissue Regeneration*

The success of an implant is determined by its integration into the tissue surrounding the biomaterial. Surface roughness is considered to influence the behavior of adherent cells. The aim of this in vitro study was to determine the effect of surface roughness on Saos-2 osteoblast-like cells. Titanium disks blasted with 75 micrometer aluminum oxide particles and machined titanium disks were prepared. Saos-2 were plated on the disks at a density of 50,000 cells per well in 48-well dishes. After 1 hour, 1 day, 6 days cell numbers were counted. One day, 6 days after plating, alkaline phosphatase(ALPase) activity was determined. Compared to experimental group, the number of cells was significantly higher on control group. The stimulatory effect of surface roughness on ALPase was more pronounced on the experimental group than on control group. These results demonstrate that surface roughness alters proliferation and differentiation of osteoblasts. The results also suggest that implant surface roughness may play a role in determining phenotypic expression of cells.
Aluminum Oxide ; Cell Count ; Osteoblasts* ; Titanium*

PURPOSE: The purpose of this study was to investigate the incidence of curet fracture and its contributing factors. MATERIAL AND METHODS: Fifty-eight periodontal curets which were broken during periodontal treatment in Kangnung National University Dental Hospital for 1 year were used as study materials. The blade thickness of new curets and broken ones was measured using a digital micrometer. Types of treatment procedures, clinical experience of operators, point of breakage, and method of removal of broken fragments were recorded for each broken curet. RESULTS: The incidence of curet fracture in root planing (16.4 curets per 1,000 procedures) was higher than those in flap surgery (7.5) or supragingival scaling (2.7). No curet was broken during supportive periodontal treatment. The incidence of fracture did not seem to be related with clinical experience of operators. The most frequent breakage point of the curets were upper 1/3 of blades. Fifty-six of 58 broken fragments were removed by non-surgical methods. Two broken tips which could not removed non-surgically were left in the pockets, and proved to be removed spontaneously 1 week later. CONCLUSION: Root planing showed higher incidence of curet fracture than any other type of periodontal treatment. Most of the fractured fragments were removed by non-surgical method. Further study is needed to develop methods of removal of the fragments which can not be removed non-surgically.
Dental Scaling ; Incidence ; Root Planing

PURPOSE: Osteotome sinus floor elevation (OSFE) is an often-used technique of great utility in certain implant patients with resorbed posterior maxilla. Recently benign paroxysmal positional vertigo (BPPV) has been reported as an early postoperative complication following OSFE. Although OSFE-induced BPPV commonly resolves itself within a month without treatment, this complication can be a cause of trouble between the implant surgeon and patient. This report presents a case of BPPV following OSFE. METHODS: A 27-year-old man without any significant medical problems and missing his maxillary right first molar, was scheduled for OSFE and simultaneous implant placement. RESULTS: The patient suffered dizziness accompanied by nausea immediately after implant placement using OSFE. Following referral to the ear nose throat clinic, "right posterior canal BPPV" was diagnosed. Despite anti vertigo medication and a single episode of the Epley maneuver, the condition did not improve completely. The Epley maneuver was then applied 7 and 8 days later and the symptoms of BPPV disappeared. One year later, the patient remained symptom-free. CONCLUSIONS: Before sinus elevation with an osteotome, implant surgeons should screen out patients with a history of vertigo, to diminish the possibility of BPPV. Operators should be aware of BPPV symptoms. As the symptoms may be very incapacitating, immediate referral to an otorhinolaryngologist is recommended.
Adult ; Dizziness ; Ear ; Floors and Floorcoverings ; Humans ; Maxilla ; Maxillary Sinus ; Molar ; Nausea ; Nose ; Outpatients ; Pharynx ; Postoperative Complications ; Referral and Consultation ; Vertigo

BACKGROUND: Incomplete flap coverage or early exposure over implants and/or barrier membranes have a negative effect on bone regeneration. In cases of using regenerative techniques, complete soft tissue coverage of the implant area is necessary to promote adequate conditions for guided bone regeneration. Primary socket closure may be difficult, when periosteal releasing incision is only used, due to the opening left by extracted tooth. Therefore, Soft tissue grafting techniques are used to achieve primary soft tissue closure. MATERIALS AND METHODS: Soft tissue grafting techniques, with or without barrier membranes, were performed for primary closure in four cases of immediate placements. Three different methods were used (CTG, VIP-CT, Palatal advanced flap). Clinical results of the grafting were evaluated. RESULT: One case showed early exposure of cover-screw and, no other complications were noted. In the others, Primary closure was achieved by soft tissue grafting techniques. One of the cases, Graft showed partial necrosis, but there were no exposure over implants and/or barrier membranes. CONCLUSION: The use of grafting techniques, in immediate implant placement, can predictably obtain primary closure of extraction sockets, thereby providing predictable bone formation and improved implant results.
Bone Regeneration ; Membranes ; Necrosis ; Osteogenesis ; Tissue Transplantation ; Tooth ; Transplants