Purpose: This study aimed to evaluate the long-term cumulative survival rate (CSR) of dental implants with micro-threads in the neck over a 10-year follow-up period and to examine the factors influencing the survival rate of dental implants. Methods: This retrospective study was based on radiographic and dental records. In total, 151 patients received 490 Oneplant ® dental implants with an implant neck micro-thread design during 2006–2010 in the Department of Periodontology of Seoul National University Dental Hospital. Implant survival was evaluated using Kaplan–Meier analysis. Cox proportional hazard regression analysis was used to identify the factors influencing implant failure. Results: Ten out of 490 implants (2.04%) failed due to fixture fracture. The CSR of the implants was 97.9%, and no significant difference was observed in the CSR between externaland internal-implant types (98.2% and 97.6%, respectively,P=0.670). In Cox regression analysis, 2-stage surgery significantly increased the risk of implant failure (hazard ratio: 4.769, P=0.039). There were no significant differences in influencing factors, including sex, age, implant diameter, length, fixture type, location, surgical procedure, bone grafting, and restoration type. Conclusions Within the limitations of this retrospective study, the micro-thread design of the implant neck was found to be favorable for implant survival, with stable clinical outcomes.

OBJECTIVE: Mitophagy is known to contribute towards progression of Parkinson's disease. Korean red ginseng (KRG) is a widely used medicinal herb in East Asia, and recent studies have reported that KRG prevents 1-methyl-4-phenylpyridinium ion (MPP METHODS: SH-SY5Y cells were incubated with KRG for 24 h, and subsequently exposed to MPP RESULTS: MPP CONCLUSION KRG effectively prevents MPP
1-Methyl-4-phenylpyridinium/toxicity* ; Apoptosis ; Cell Line, Tumor ; Mitochondria ; Mitophagy ; Panax ; Reactive Oxygen Species

PURPOSE: This study aimed to evaluate the effect of two different implant-abutment connection structures with identical implant design on peri-implant bone level. MATERIALS AND METHODS: This clinical study was a patient-blind randomized controlled trial following the CONSORT 2010 checklists. This trial was conducted in 24 patients recruited between March 2013 and July 2015. Implants with internal friction connection were compared to those with external hex connection. One implant for each patient was installed, replacing the second molar. Implant-supported crowns were delivered at four months after implant insertion. Standardized periapical radiographs were taken at prosthesis delivery (baseline), and one year after delivery. On the radiographs, distance from implant shoulder to first bone-to-implant contact (DIB) and peri-implant area were measured, which were the primary and secondary outcome, respectively. RESULTS: Eleven external and eleven internal implants were analyzed. Mean changes of DIB from baseline to 1-year postloading were 0.59 (0.95) mm for the external and 0.01 (0.68) mm for the internal connection. Although no significant differences were found between the two groups, medium effect size was found in DIB between the connections (Cohen's d = 0.67). CONCLUSION: Considering the effect size in DIB, this study suggested the possibility of the internal friction connection structure for more effective preservation of marginal bone.
Alveolar Bone Loss ; Checklist ; Clinical Study ; Crowns ; Dental Implant-Abutment Design ; Friction ; Humans ; Molar ; Prostheses and Implants ; Shoulder

PURPOSE: The purpose of this retrospective study with 4–12 years of follow-up was to compare the marginal bone loss (MBL) between external-connection (EC) and internal-connection (IC) dental implants in posterior areas without periodontal or peri-implant disease on the adjacent teeth or implants. Additional factors influencing MBL were also evaluated. METHODS: This retrospective study was performed using dental records and radiographic data obtained from patients who had undergone dental implant treatment in the posterior area from March 2006 to March 2007. All the implants that were included had follow-up periods of more than 4 years after loading and satisfied the implant success criteria, without any peri-implant or periodontal disease on the adjacent implants or teeth. They were divided into 2 groups: EC and IC. Subgroup comparisons were conducted according to splinting and the use of cement in the restorations. A statistical analysis was performed using the Mann-Whitney U test for comparisons between 2 groups and the Kruskal-Wallis test for comparisons among more than 2 groups. RESULTS: A total of 355 implants in 170 patients (206 EC and 149 IC) fulfilled the inclusion criteria and were analyzed in this study. The mean MBL was 0.47 mm and 0.15 mm in the EC and IC implants, respectively, which was a statistically significant difference (P < 0.001). Comparisons according to splinting (MBL of single implants: 0.34 mm, MBL of splinted implants: 0.31 mm, P=0.676) and cement use (MBL of cemented implants: 0.27 mm, MBL of non-cemented implants: 0.35 mm, P=0.178) showed no statistically significant differences in MBL, regardless of the implant connection type. CONCLUSIONS: IC implants showed a more favorable bone response regarding MBL in posterior areas without peri-implantitis or periodontal disease.
Alveolar Bone Loss ; Dental Implant-Abutment Design ; Dental Implants ; Dental Records ; Follow-Up Studies ; Humans ; Peri-Implantitis ; Periodontal Diseases ; Retrospective Studies ; Splints ; Tooth

PURPOSE: Periodontitis and rheumatoid arthritis (RA) share a similar inflammatory pathogenesis. Porphyromonas gingivalis (Pg) can induce anticyclic-citrullinated peptide autoantibodies (anti-CCP antibodies), a key factor in the development of RA. This study aimed at evaluating the relationships between the 2 diseases and identifying the clinical implications thereof, with a focus on periodontal pathogens in Korean adults. METHODS: A total of 260 RA patients and 86 age- and sex-matched control patients without arthritis were enrolled in this prospective cross-sectional study. Periodontal indices and the prevalence and amount of periodontal pathogens were compared between the groups. Correlations between periodontal and RA indices were examined, as were correlations between 9 periodontal pathogens and RA indices. RESULTS: The RA group had significantly higher values than the control group for all investigated periodontal indices (P < 0.05) except the number of teeth. The gingival index (GI) was correlated with the disease activity score 28 (DAS28) (r = 0.125, P = 0.049), RA disease duration (r = 0.253, P < 0.001), erythrocyte sedimentation rate (ESR) (r = 0.162, P = 0.010), and anti-CCP antibody titer (r = 0.205, P = 0.004). Probing pocket depth (PPD) was correlated with ESR (r = 0.139, P = 0.027) and anti-Pg antibody titer (r = 0.203, P = 0.001). Bleeding on probing (BOP) was correlated with DAS28 (r = 0.137, P = 0.030), RA disease duration (r = 0.202, P = 0.001), ESR (r = 0.136, P = 0.030), anti-Pg antibody titer (r = 0.177, P = 0.005), and anti-CCP antibody titer (r = 0.188, P = 0.007). Clinical attachment level (CAL) and periodontitis severity were correlated with anti-Pg antibody titer (the former r = 0.201, P = 0.002; the latter r = 0.175, P = 0.006). The quantity of Pg was positively correlated with the serum anti-Pg antibody titer (r = 0.148, P = 0.020). CONCLUSIONS: The GI, BOP, and PPD showed positive relationships with several RA indices. The anti-Pg antibody titer had positive relationships with PPD, BOP, CAL, and periodontitis severity. Thus, increasing values of periodontal indices could be used as a risk indicator of disease development in RA patients, and an increasing anti-Pg antibody titer could be considered as a warning sign in RA patients suffering with periodontitis.
Adult ; Arthritis ; Arthritis, Rheumatoid ; Autoantibodies ; Blood Sedimentation ; Cross-Sectional Studies ; Hemorrhage ; Humans ; Periodontal Index ; Periodontitis ; Porphyromonas gingivalis ; Prevalence ; Prospective Studies ; Tooth

OBJECTIVETo investigate the potential alleviating effects of acupuncture on maternal separation (MS)-induced changes in plasma pro-inflammatory cytokine levels of rat pups.

METHODSOn postnatal day 15, rat pups were randomly assigned to 4 groups (n=6 per group) using a random number table: normal, MS, MS with acupuncture stimulation at Shenmen (HT 7) acupoint (MS+HT 7), and MS with acupuncture stimulation at Chengshan (BL 57) acupoint (MS+BL 57) groups. Rat pups in the normal group were housed with their mothers under standard conditions; those in the MS, MS+HT 7 and MS+BL 57 groups were maternally separated and individually maintained. Acupuncture stimulation was performed at HT 7 or BL 57 acupoints once a day for 7 consecutive days. A tail suspension test was performed to measure immobility time of rats and the plasma was collected on postnatal day 21, then levels of corticosterone (CORT), interleukin (IL)-1β, IL-6 and glial cell-derived neurotrophic factor (GDNF) in plasma were measured.

RESULTSCompared with the normal group, the immobility time and the plasma levels of CORT, IL-1β, IL-6 and GDNF in the MS group were significantly increased (P<0.05 or P<0.01). Compared with the MS group, the immobility time and the plasma levels of CORT, IL-1β, IL-6 and GDNF were significantly reduced in the MS+HT 7 group (P<0.05 or P<0.01). Moreover, the immobility time and plasma levels of IL-1β and IL-6 in the MS+HT 7 group were significantly lower than those in the MS+BL 57 group (P<0.05).

CONCLUSIONAcupuncture stimulation at HT 7 can alleviate the behavioral impairment and changes of the cytokines by MS, indicating that acupuncture can help to relieve MS-induced depression.

PURPOSE: The aim of this study was to radiographically and clinically compare the effect of extracellular matrix (ECM) membranes on dimensional alterations following a ridge preservation procedure. METHODS: One of 2 different ECM membranes was applied during a ridge preservation procedure. A widely used ECM membrane (WEM; Bio-Gide, Geistlich Biomaterials, Wolhusen, Switzerland) was applied in the treatment group and a newly developed ECM membrane (NEM; Lyso-Gide, Oscotec Inc., Seongnam, Korea) was applied in the control group. Cone-beam computed tomography (CBCT) scans and alginate impressions were obtained 1 week and 6 months after the ridge preservation procedure. Results were analyzed using the independent t-test and the nonparametric Mann-Whitney U test. RESULTS: There were no significant differences between the ECM membranes in the changes in the dimension, width, and height of the extraction socket or the quantity of bone tissue. CONCLUSIONS: The NEM showed comparable clinical and radiographic results to the WEM following the ridge preservation procedure.
Alveolar Bone Grafting ; Alveolar Process* ; Biocompatible Materials ; Bone and Bones ; Bone Regeneration ; Clinical Study* ; Cone-Beam Computed Tomography ; Extracellular Matrix ; Gyeonggi-do ; Imaging, Three-Dimensional ; Membranes* ; Tooth Socket

PURPOSE: The purpose of this study was to investigate the feasibility of regenerative therapy with a collagenated bone graft and resorbable membrane in intrabony defects, and to evaluate the effects of the novel extracellular matrix (ECM)-based membrane clinically and radiologically. METHODS: Periodontal tissue regeneration procedure was performed using an ECM-based resorbable membrane in combination with a collagenated bovine bone graft in intrabony defects around the teeth and implants. A novel extracellular matrix membrane (NEM) and a widely-used membrane (WEM) were randomly applied to the test group and the control group, respectively. Cone-beam computed tomography images were obtained on the day of surgery and 6 months after the procedure. Alginate impressions were taken and plaster models were made 1 week and 6 months postoperatively. RESULTS: The quantity of bone tissue, the dimensional changes of the surgically treated intrabony defects, and the changes in width and height below the grafted bone substitutes showed no significant difference between the test and control groups at the 6-month examination. CONCLUSIONS: The use of NEM for periodontal regeneration with a collagenated bovine bone graft showed similar clinical and radiologic results to those obtained using WEM.
Bone and Bones ; Bone Regeneration ; Bone Substitutes ; Clinical Study* ; Collagen* ; Cone-Beam Computed Tomography ; Extracellular Matrix ; Guided Tissue Regeneration ; Imaging, Three-Dimensional ; Membranes* ; Regeneration* ; Tooth ; Transplants*

PURPOSE: This article describes a case of the successful non-surgical management of a periodontally compromised maxillary premolar. METHODS: A combination therapy, including root planing, occlusal adjustment, and tooth splinting, was applied. Clinical and radiographic examinations were performed during the 16-month follow-up period. RESULTS: All periodontal parameters were improved. There were dramatic decreases (3–6 mm) in the probing pocket depth, tooth mobility, and marginal bone loss. Interestingly, gradual resolution of the periapical radiolucency and alveolar bone regeneration were observed in the radiographs, and the periodontal condition was maintained during the follow-up period. CONCLUSIONS: Within the limits of this study, these results demonstrate the importance of natural tooth preservation through proper periodontal treatment and occlusal adjustment of the periodontally compromised tooth, which is typically targeted for tooth extraction and dental implantation.
Bicuspid ; Bone Regeneration ; Dental Implantation ; Dental Implants ; Dental Occlusion, Traumatic ; Follow-Up Studies ; Occlusal Adjustment ; Periodontitis ; Root Planing ; Splints ; Tooth Extraction ; Tooth Mobility ; Tooth*

PURPOSE: The aim of this study was to determine the relationship between buccal bone thickness and gingival thickness by means of a noninvasive and relatively accurate digital registration method. METHODS: In 20 periodontally healthy subjects, cone-beam computed tomographic images and intraoral scanned files were obtained. Measurements of buccal bone thickness and gingival thickness at the central incisors, lateral incisors, and canines were performed at points 0–5 mm from the alveolar crest on the superimposed images. The Friedman test was used to compare buccal bone and gingival thickness for each depth between the 3 tooth types. Spearman's correlation coefficient was calculated to assess the correlation between buccal bone thickness and gingival thickness. RESULTS: Of the central incisors, 77% of all sites had a buccal thickness of 0.5–1.0 mm, and 23% had a thickness of 1.0–1.5 mm. Of the lateral incisors, 71% of sites demonstrated a buccal bone thickness <1.0 mm, as did 63% of the canine sites. For gingival thickness, the proportion of sites <1.0 mm was 88%, 82%, and 91% for the central incisors, lateral incisors, and canines, respectively. Significant differences were observed in gingival thickness at the alveolar crest level (G0) between the central incisors and canines (P=0.032) and between the central incisors and lateral incisors (P=0.013). At 1 mm inferior to the alveolar crest, a difference was found between the central incisors and canines (P=0.025). The lateral incisors and canines showed a significant difference for buccal bone thickness 5 mm under the alveolar crest (P=0.025). CONCLUSIONS: The gingiva and buccal bone of the anterior maxillary teeth were found to be relatively thin (<1 mm) overall. A tendency was found for gingival thickness to increase and bone thickness to decrease toward the root apex. Differences were found between teeth at some positions, although the correlation between buccal bone thickness and soft tissue thickness was generally not significant.
Cone-Beam Computed Tomography ; Gingiva ; Healthy Volunteers ; Incisor ; Maxilla ; Methods* ; Radiographic Image Interpretation, Computer-Assisted ; Tooth