PURPOSE: Root resection can be a valuable procedure when the tooth in question has a high strategic value. The prognosis of root resection has been well documented in previous studies, but the results focused on the palatal root resection have not been discussed in depth. I represent here the short term effectiveness of palatal root resection of maxillary first molars. METHODS: Palatal root resection was performed on maxillary first molars of three patients. All the palatal roots were floating state on the radiographic finding and showed full probing depth and purulent exudation at initial examination. Reduction of palatal cusp and occlusal table was performed concomitantly. Endodontic therapy was completed after root resection. RESULTS: Compromised maxillary first molars were treated successfully by palatal root resection in 3 cases. The mobility of resected tooth was decreased a little bit. The probing pocket depth of remaining buccal roots was not increased compared to initial depth. All the patients satisfied with comfort and cost effective results and the fact they could save their natural teeth. CONCLUSIONS: Within the above results, palatal root resection is an effective procedure treating compromised maxillary first molar showing advanced palatal bone loss to root apex with or without pulp involvement when proper case selection is performed.
Humans ; Isothiocyanates ; Maxilla ; Molar ; Palate ; Prognosis ; Tooth ; Tooth Root

PURPOSE: Following tooth extraction caused by severe periodontitis, alveolar ridge dimension lose their original volume. To reduce the alveolar ridge dimension, the ridge preservation technique has been introduced and tested in many clinical studies with membrane alone or membrane plus graft, achieving reduced ridge loss compared to extraction only. The aim of the present clinical study was to compare the post-extraction dimensional changes in the membrane exposure group to non-exposure group during healing period following ridge preservation technique. METHODS: Ridge preservation was performed in 44 extraction sites. After extraction, deproteinized bovine bone mineral coated with synthetic oligopeptide (Ossgen-X15(R)) or deproteinized bovine bone mineral (Bio-Oss(R)) was implanted into the socket. A collagen membrane (Bio-Gide(R)) was trimmed to cover the socket completely and applied to the entrance of the socket. Four clinical parameters were compared between baseline and 6 months. RESULTS: During healing period, membrane exposure was observed at 19 sites. At the re-entry, hard newly formed tissue were observed at the ridge preservation site. The grafted socket sites were well preserved in their volume dimension. In both groups, horizontal ridge width was reduced and vertical height was increased. There were not statistically significant differences in horizontal (-1.32 mm vs -1.00 mm) and vertical ridge change (2.24 mm vs 2.37 mm at buccal crest, 1.36 mm vs. 1.53 mm at lingual crest) between two groups. CONCLUSIONS: The ridge preservation approach after tooth extraction effectively prevented resorption of hard tissue ridge in spite of membrane exposure during healing period.
Alveolar Process ; Bone Substitutes ; Collagen ; Membranes ; Periodontitis ; Tooth Extraction ; Tooth Socket ; Transplants

In 2010, the Journal of the Korean Academy of Periodontology will be renamed to the Journal of Periodontal & Implant Science to commemorate the 50th anniversary of the Korean Academy of Periodontology. The official language of the Journal of Periodontal & Implant Science is English to encourage submissions from international authors and to provide adequate distribution of the articles. The Journal of Periodontal & Implant Science is a peer-reviewed journal providing current information relevant to professionalism of periodontology & periimplantology and welcomes practical clinical reports, sophisticated original articles and fundamental reviews covering broad range of interests within the scope from anyone around the world.
Anniversaries and Special Events

PURPOSE: The objective of this clinical presentation was to present a clinical case series report of socket preservation, sinus augmentation, and bone grafting using a horse-derived biomaterial. METHODS: A horse-derived biomaterial was used in 8 patients for different indications including socket preservation following tooth extraction, osseous bone grafting, and sinus augementation procedures. Surgeries were performed by a well trained specialist and clinical radiographs were obtained at designated intervals. Biopsy cores of 2 x 8 mm prior to implant placement was obtained following a healing interval of 4 - 6 months. A clinical and histologic evaluation was performed to evaluate the clinical effectiveness and biocompatibility of the biomaterial. RESULTS: All surgeries in 8 patients were successful with uneventful healing except for one case with membrane exposure that eventually resulted with a positive outcome. Radiographic display of the healing phase during different intervals showed increased radiopacity of granular nature as the healing time increased. No signs of adverse effect or infection was observed clinically and the tissues surrounding the biomaterial seemed well-tolerated with good intentional healing. The augmented sinuses healed uneventfully suggesting in part, good biocompatibility of the biomaterial. Dental implants placed following socket preservation were inserted with high initial torque suggesting good initial stability and bone quality. CONCLUSIONS: Our results show that at least on a tentative level, a horse-derived biomaterial may be used clinically in socket preservation, sinus augmentation, bone grafting techniques with good intentional healing and positive results.
Biocompatible Materials ; Biopsy ; Bone Substitutes ; Bone Transplantation ; Dental Implants ; Humans ; Membranes ; Specialization ; Tooth Extraction ; Torque ; Wound Healing

PURPOSE: Gene therapy (ex vivo) has recently been used as a means of delivering bone morphogenetic proteins (BMPs) to sites of tissue regeneration. In the present study, we investigated the effect of co-transduction of adenoviruses expressing BMP-2 and BMP-7 on osteogenesisof C2C12 cells in vitro. METHODS: A replication-defective human adenovirus 5 (Ad5) containing a cDNA for BMPs in the E1 region of the virus (Ad5BMP-2 and Ad5BMP-7) was constructed by in vivo homologous recombination. Functional activity of Ad5BMP-2 and Ad5BMP-7 were evaluated in mouse stromal cells (W20-17cells). C2C12 cells are transduced with various MOI (multiplicity of infection) of Ad5BMP-2 and Ad5BMP-7 to assess most effective and stable titer. Based on this result, C2C12 cells were transduced with Ad5BMP-2 and Ad5BMP-7 alone or by combination. BMPs expression, alkaline phosphatase (ALPase) activity, cell proliferation, and mineralization were assessed. RESULTS: Ad5BMP-2 and Ad5BMP-7 are successfully transduced to W20-17 cells, and secreted BMPs stimulated cell differentiation. Also, C2C12 cells transduced with Ad5BMPs showed expression of BMPs and increased ALPaseactivity. In all groups, cell proliferation was observed over times. At 7days, cells co-transduced with Ad5BMP-2 and Ad5BMP-7 showed lower proliferation than the others. C2C12 cells co-transduced with Ad5BMP-2 and Ad5BMP-7 had greater ALPaseactivity than that would be predicted if effect of individual Ad5BMPs were additive. Little mineralized nodule formation was detected in cells transduced with individual Ad5BMPs. In contrast, Ad5BMP-2 and Ad5BMP-7 combination stimulated mineralization after culturing for 10 days in mineralizing medium. CONCLUSIONS: Present study demonstrated that adenoviruses expressing BMPs gene successfully produced BMPs protein and these BMPs stimulated cells to be differentiated into osteoblastic cells. In addition, the osteogenic activity of Ad5BMPs can be synergistically increased by co-transduction of cells with Ad5BMP-2 and Ad5BMP-7.
Adenoviridae ; Adenoviruses, Human ; Alkaline Phosphatase ; Animals ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Protein 7 ; Bone Morphogenetic Proteins ; Cell Differentiation ; Cell Proliferation ; DNA, Complementary ; Durapatite ; Genetic Therapy ; Homologous Recombination ; Mice ; Osteoblasts ; Osteogenesis ; Regeneration ; Stromal Cells ; Viruses

PURPOSE: The aim of this study was to investigate matrix metalloproteinase 1 (MMP-1) gene polymorphism (1G/2G at -1607 and A/G at -519) in Korean subject and to assess the association between polymorphism and periodontal status. METHODS: Forty nine generalized aggressive periodontitis (GAP) patients and 57 periodontally healthy children were recruited and genomic DNA was extracted from buccal swab. The polymorphisms of MMP-1 promoter genes were determined by polymerase chain reaction and restriction fragment length product (PCR-RFLP) method. The distribution of genotype and allele frequency was compared between 2 groups by chi-square test. RESULTS: There was a significant difference in the distribution of genotypes and frequency of alleles between the GAP and reference groups at the position - 519 of MMP-1 gene promoter (P< 0.05). Allele G carrier rate was significantly lower in GAP group than that of the reference group (P< 0.001). At the position -1607 of MMP-1 gene promoter, genotype distribution and allele frequency showed no statistically significant difference between the groups. However, in the female group, a significant difference was observed between the groups for the genotype distribution, allele frequency and allele 1G carrier rate (P< 0.05). CONCLUSIONS: The DNA polymorphism at the MMP-1 gene promoter might be associated with GAP in Korean.
Aggressive Periodontitis ; Alleles ; Child ; DNA ; Female ; Gene Frequency ; Genotype ; Humans ; Matrix Metalloproteinase 1 ; Polymerase Chain Reaction ; Polymorphism, Genetic

PURPOSE: To estimate the prevalence of periodontitis in Korean adults and to examine the associations between periodontitis and known risk factors. METHODS: Using Korean National Oral Health Survey 2006 data, a total of 4,263 people who had taken oral examination, interviewed by questionnaire, and aged 18 or older were sampled. The prevalence of periodontitis measured by Community Periodontal Index (CPI) was calculated and the differences in prevalence according to known risk factors (age, sex, monthly income, education, residential area, tooth-brushing frequency, regular dental visit, smoking, and diabetes) were examined with chi-square test. Logistic regression analysis was performed to see the effects of each risk factor on the risk of having periodontitis. All statistical approaches were reflected national sampling design using Survey procedures in SAS 9.1. RESULTS: The overall prevalence of periodontitis in Korean adults was 10.3%. There existed statistically significant differences in crude prevalence for periodontitis according to the all risk factors. In logistic regression, older age groups (O.R.:2.94-3.71), people living in rural area (O.R.:1.87), and current smokers (O.R.:1.77) were significantly prone to have periodontitis. People who earned monthly income of more than 2 million Korean won (O.R.:0.64) and brushed their teeth two or more times per day (O.R.:0.60-0.62) had significantly lower risk of having periodontitis. CONCLUSIONS: About 10% of Korean adults had periodontitis in 2006. People who were older, living in rural region, in lower income status, smoking, less tooth brushing were more likely to have periodontitis.
Adult ; Aged ; Diagnosis, Oral ; Humans ; Logistic Models ; Oral Health ; Periodontal Index ; Periodontitis ; Phenothiazines ; Prevalence ; Surveys and Questionnaires ; Risk Factors ; Smoke ; Smoking ; Tooth

PURPOSE: This study was aimed to evaluate the effect of implant drilling speed on the composition of particle size of collected bone debris. METHODS: Branemark System (R)drills were used to collect bone debris from 10 drilling holes (1 unit) at 1,500 rpm (Group A) and 800 rpm (Group B) in bovine mandible. After separating particles by size into > 500 microm, between 250 microm and 500 microm, and < 250 microm fractions, particle wet volume, dry volume, and weight were measured and the proportion of 3 fractions of bone debris to total wet volume, dry volume and weight was calculated as wet volume % , dry volume % and weight %. RESULTS: No significant differences were found between Group A and B in wet volume, dry volume, and weight. However, of > 500 microm fractions, Group B had significantly higher wet volume % (P = 0.0059) and dry volume % (P = 0.0272) than in Group A. CONCLUSIONS: The drilling speed influenced the composition of particle size in collected drilling bone debris. The drilling in 800 rpm produced the more percentage of large particles than in 1,500 rpm. However, the drilling speed didn't effect on total volume of and weight of bone debris.
Dental High-Speed Technique ; Dental Implantation ; Mandible ; Mandrillus ; Particle Size

PURPOSE: Full-mouth disinfection enables to reduce the probability of cross contamination from untreated pockets to treated ones, for completing the entire SRP under local anesthesia with chlorhexidine as a mouth wash in two visits within 24 hours. This study aimed to compare the clinical effects of modified full-mouth disinfection (Fdis) after 6 months with those of conventional SRP (cSRP). METHODS: Thirty non-smoking chronic periodontitis subjects were randomly allocated two groups. The Fdis group underwent the entire SRP under local anesthesia in two visits within 24 hours, a week after receiving supragingival scaling. A chlorhexidine (0.1%) solution was used for rinsing and subgingival irrigation for Fdis. The cSRP group received SRP per quadrant under local anesthesia at one-week intervals, one week after they had received scaling. Clinical parameters were recorded at baseline, after 1, 3 and 6 months. RESULTS: There are significant (P< 0.05) decreases in the sulcus bleeding index, and plaque index, and the increases in gingival recession were significantly smaller with Fdis after six months compared with cSRP. There was significant improvement in the probing depth and clinical attachment level for initially medium-deep pockets (4-6mm) after Fdis compared with cSRP. Multi-rooted teeth showed significantly larger attachment gain up to six months after Fdis. Single-rooted teeth showed significantly more attachment gain, 1 and 6 months after Fdis. CONCLUSIONS: Fdis has more beneficial effects on reducing gingival inflammation, plaque level, probing depth, gingival recession and improving clinical attachment level over cSRP.
Anesthesia, Local ; Chlorhexidine ; Chronic Periodontitis ; Dental Scaling ; Disinfection ; Gingival Recession ; Hemorrhage ; Humans ; Inflammation ; Mouth ; Tooth

PURPOSE: Cytolethal distending toxin (CDT) is a family of heat-labile cytotoxins produced by several gram-negative mucosa-associated pathogens, including Aggregatibacter actinomycetemcomitans. CDT is well known to be capable of inducing growth arrest, morphological alterations, and eventually death in various cells. CDT belongs to a tripartite AB2 toxin (CdtB: the enzymatic A subunit ; CdtA and CdtC: the heterodimeric B subunit). Previous studies proposed that CdtA and CdtC together bind to a cell surface receptor and glycolipids act as a receptor for A. actinomycetemcomitans CDT (AaCDT). In this study, recombinant CdtA and CdtC proteins of AaCDT were co-expressed in a bacterial expression system and tested for their affinity for GM1 ganglioside. METHODS: The genes for CdtA and CdtC from A. actinomycetemcomitans Y4 were utilized to construct the expression vectors, pRSET-cdtA and pET28a-cdtC. Both CdtA and CdtC proteins were expressed in Escherichia coli BL21(DE3) and then purified using hexahistidine (His6) tag. The identity of purified protein was confirmed by anti-His6 antibody and monoclonal anti-CdtA antibody. Furthermore, the affinity of recombinant protein to GM1 ganglioside was checked through ELISA. RESULTS: Recombinant CdtA and CdtC proteins were expressed as soluble proteins and reacted to anti-His6 and monoclonal anti-CdtA antibodies. ELISA revealed that purified soluble CdtA-CdtC protein bound to GM1 ganglioside, while CdtA alone did not. CONCLUSIONS: Co-expression of CdtA and CdtC proteins enhanced the solubility of the proteins in E. coli, leading to convenient preparation of active CdtA-CdtC, a critical material for the study of AaCDT pathogenesis.
Antibodies ; Bacterial Toxins ; Cytotoxins ; Edetic Acid ; Enzyme-Linked Immunosorbent Assay ; Escherichia coli ; Glycolipids ; Histidine ; Humans ; Oligopeptides ; Proteins ; Solubility