• Journal of Periodontal and Implant Science
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• v.51 no.6
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• pp.422-432
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• 2021

Purpose: The aim of this study was to compare straight and tapered implant designs in terms of marginal bone loss, the modified plaque index (mPI), and the modified bleeding index (mBI) for 5 years after functional loading. Methods: Twelve patients were recruited. Two types of implants were placed adjacent to each other: 1 straight implant and 1 tapered implant. Marginal bone loss, mPI, and mBI were measured every year for 5 years after loading. Results: The straight implants showed 0.2±0.4 mm of marginal bone loss at 5 years after loading, while the tapered implants showed 0.2±0.3 mm of marginal bone loss; this difference was not statistically significant (P=0.833). Our analysis also showed no statistically significant differences in mPI (straight implants: 0.3±0.3 vs. tapered implants: 0.2±0.3; P=0.414) or in mBI (straight implants: 0.3±0.4 vs. tapered implants: 0.2±0.3; P=0.317) at 5 years after prosthesis delivery. Conclusions: Straight and tapered implants showed no significant differences with respect to marginal bone loss, mPI, and mBI for 5 years after loading.

• The Journal of Advanced Prosthodontics
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• v.8 no.4
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• pp.313-320
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• 2016

PURPOSE. The aim of this study was to evaluate the clinical findings and patient satisfaction on implant overdenture designed with Locator implant attachment or Locator bar attachment in mandibular edentulous patients. MATERIALS AND METHODS. Implant survival rate, marginal bone loss, probing depth, peri-implant inflammation, bleeding, plaque, calculus, complications, and satisfaction were evaluated on sixteen patients who were treated with mandibular overdenture and have used it for at least 1 year (Locator implant attachment: n=8, Locator bar attachment: n=8). RESULTS. Marginal bone loss, probing depth, plaque index of the Locator bar attachment group were significantly lower than the Locator implant attachment group (P<.05). There was no significant difference on bleeding, peri-implant inflammation, and patient satisfaction between the two denture types (P>.05). The replacement of the attachment components was the most common complication in both groups. Although there was no correlation between marginal bone loss and plaque index, a significant correlation was found between marginal bone loss and probing depth. CONCLUSION. The Locator bar attachment group indicates lesser marginal bone loss and need for maintenance, as compared with the Locator implant attachment group. This may be due to the splinting effect among implants rather than the types of Locator attachment.

• Journal of Periodontal and Implant Science
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• v.39 no.1
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• pp.27-36
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• 2009

Purpose: The stability of periodontal condition and marginal bone level were important to achieve long-term success of dental implant treatment. The aim of this study was to evaluate periodontal conditions and marginal bone loss around 67 GSII(OSSTEM, Seoul, Korea) dental implants with dual-microthread at the neck portion, 1 year after prosthetic loading. Materials and methods: Sixty-seven GS II dental implants in 27 patients(mean age; $47.4{\pm}14.0$ years) who received implant treatments at Pusan National University Hospital, were included in this study. Thirteen US II(OSSTEM, Seoul, Korea) implants with smooth neck design were selected for the control group. Periodontal and radiographic evaluations were carried out at baseline, 6 months and 12 months after prosthetic loading. Results: In the GS II group, plaque index(PI), gingival index(GI) and probing depth(PD) increased as time passed. In the US II group, GI and PD increased. Although marginal bone level was lower in the US II group in all evaluation periods, the changes between the periods were not statistically significant(p>0.05). In each period, periodontal parameters were not statistically significant between groups. Conclusion: One year after prosthetic loading, GS II and US II dental implants showed similar periodontal conditions and marginal bone response, and were within the criteria of success.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.1
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• pp.50-58
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• 2000

The purpose of this study was to investigate the causes of food impaction and to explore solutions as well. For this study, 39 patients with food impaction were selected. 77 contact areas in these patients were investigated mobility, tightness of contact area, gingival index, plaque index, attachment loss, alveolar bone loss, proximal caries, marginal ridge distance and occlusal relationships. The results were as follows ; 1. Teeth without distal support were found to be the most frequent site of food impaction (41.6%). Food impaction was found to be more frequent in the upper teeth (65.2%) than the lower teeth (33.8%). 2. Food impaction was found in tight contact cases (71.4%). Alveolar bone loss was not found in the early stage of food impaction (83.1%) 3. The distance between the marginal ridges of food impaction sites (mean=0.48mm) was short-er than that of the control group. (mean=0.77mm) (p<0.001) 4. In 18.2% of the cases, proximal carries were found at the food impaction site. 5. Food impaction affected patient's occlusion with the following frequencies, cusp to marginal ridge relationship (72.7%), cusp to fossa relationship (3.9%) and stepped relationship (23.4%).

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.2
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• pp.116-126
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• 2018

Purpose: The purpose of this study was to analyze the factors affecting the survival rate and the marginal bone level of dental implants that have functioned over 7-years. Materials and Methods: In 92 patients, 178 dental implants were included. Implant-related factors (diameter, length, prosthetic splint), patient-related factors (gender, smoking, plaque index, compliance to supportive periodontal therapy) and surgery-related factors (proficiency of surgeon, bone graft) were evaluated via clinical and radiographic examination. The marginal bone level was determined by intraoral standard radiography at the mesial and distal aspects of each implant using an image analysis software program. Results: The survival rate of all the implants was 94.94% and the marginal bone level was $0.89{\pm}1.05mm$, these results are consistent with other studies that present long-term good clinical results. Implant length and plaque index among several factors were statistically significant for implant survival rate (P < 0.05). Smoking and the presence of regeneration surgery were statistically significant for the marginal bone level (P < 0.05). Conclusion: Dental implant that have functioned over 7-years showed favorable long-term survival rates and marginal bone level. Implant length and plaque control should be considered for improving the long-term clinical results. It is needed that careful application of bone regeneration technique and smoking control for maintaining of marginal bone level.

• Restorative Dentistry and Endodontics
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• v.26 no.4
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• pp.316-325
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• 2001

The purpose of this study was to evaluate the effect of adhesive curing timing on the direction of polymerization shrinkage of light-curing composite resin. In this study, the curing times of adhesive and composite resin were measured by differential scanning calorimeter(DSC). 28 extracted human molars were embedded in clear resin and box-type cavities were prepared. Based on DSC data, the experimental teeth were divided into 4 groups. Group 1: no bond; Group 2: late curing; Group 3: Intermediate curing; Group 4: Early curing. After treating with adhesive, the buccal cavities were filled with Z-100 hybrid composite resin and the lingual ones were filled with AEliteflo flowable composite resin. The depressions at the surface were measured by surface profilometer, then the specimens were embedded in clear resin and sectioned. Impressions were obtained and used to get epoxy resin replicas. The epoxy replicas were gold-coated and observed under SEM. Average Maximum Gap(AMG), Gap Proportion(GP), Average Marginal Index(AMI) were used to compare the shrinkage gap of each group. The results were statistically analyzed using the Kruskal-Wallis One Way ANOVA, Student-Newman-Keuls method. The results of this study were as follows. 1. Average Maximum Gap, Gap Proportion, Average Marginal Index and depression at the surface or Z-100 hybride composite resin were smaller than those of AEliteflo flowable composite resin(P<0.05). 2. When the bonding between composite resin and tooth structure was strong, the shrinkage gap was small, and depression at the surface was deep(P<0.05). 3. In the well-bonded group, light-curing composite resin shrank toward bonded cavity wall, not toward light source. The result suggested that the direction of polymerization shrinkage was affected by the quality of bonding in the dentin-resin interface. The strong was the bonding between composite resin and tooth structure, the smaller was the gap and the deeper was the depression at the surface. Then the flow to compensate the polymerization shrinkage proceeded from surface to bonded cavity wall.

• The Journal of Advanced Prosthodontics
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• v.6 no.5
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• pp.325-332
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• 2014

PURPOSE. The aim of this review was to analyze the evaluation criteria on mandibular implant overdentures through a systematic review and suggest standardized evaluation criteria. MATERIALS AND METHODS. A systematic literature search was conducted by PubMed search strategy and hand-searching of relevant journals from included studies considering inclusion and exclusion criteria. Randomized clinical trials (RCT) and clinical trial studies comparing attachment systems on mandibular implant overdentures until December, 2011 were selected. Twenty nine studies were finally selected and the data about evaluation methods were collected. RESULTS. Evaluation criteria could be classified into 4 groups (implant survival, peri-implant tissue evaluation, prosthetic evaluation, and patient satisfaction). Among 29 studies, 21 studies presented implant survival rate, while any studies reporting implant failure did not present cumulative implant survival rate. Seventeen studies evaluating peri-implant tissue status presented following items as evaluation criteria; marginal bone level (14), plaque Index (13), probing depth (8), bleeding index (8), attachment gingiva level (8), gingival index (6), amount of keratinized gingiva (1). Eighteen studies evaluating prosthetic maintenance and complication also presented following items as evaluation criteria; loose matrix (17), female detachment (15), denture fracture (15), denture relining (14), abutment fracture (14), abutment screw loosening (11), and occlusal adjustment (9). Atypical questionnaire (9), Visual analog scales (VAS) (4), and Oral Health Impact Profile (OHIP) (1) were used as the format of criteria to evaluate patients satisfaction in 14 studies. CONCLUSION. For evaluation of implant overdenture, it is necessary to include cumulative survival rate for implant evaluation. It is suggested that peri-implant tissue evaluation criteria include marginal bone level, plaque index, bleeding index, probing depth, and attached gingiva level. It is also suggested that prosthetic evaluation criteria include loose matrix, female detachment, denture fracture, denture relining, abutment fracture, abutment screw loosening, and occlusal adjustment. Finally standardized criteria like OHIP-EDENT or VAS are required for patient satisfaction.

• Imaging Science in Dentistry
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• v.51 no.2
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• pp.155-165
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• 2021

Purpose: This study aimed to evaluate changes of the alveolar bone and interdental bone septum of the mandibular incisors through cone-beam computed tomography (CBCT) after orthodontic treatment of mandibular dental crowding without dental extraction. Materials and Methods: The sample consisted of 64 CBCT images(32 pre-treatment and 32 post-treatment) from 32 adult patients with class I malocclusion and an average age of 23.0±3.9 years. The width and height of the alveolar bone and interdental septum, the distance between the cementoenamel junction (CEJ) and the facial and lingual bone crests, and the inclination of the mandibular incisors were measured. Results: The distance between the CEJ and the marginal bone crest on the facial side increased significantly (P<0.05). An increased distance between the CEJ and the bone crest on the facial and lingual sides showed a correlation with the irregularity index (P<0.05); however, no significant association was observed with increasing mandibular incisor inclination (P>0.05). The change in the distance between the CEJ and the marginal bone crest on the facial side was correlated significantly with bone septum height(P<0.05). Conclusion: Bone dehiscence developed during the treatment of crowding without extraction only on the incisors' facial side. Increasing proclination of the mandibular incisor was not correlated with bone dehiscence. The degree of dental crowding assessed through the irregularity index was associated with the risk of developing bone dehiscence. The interdental septum reflected facial marginal bone loss in the mandibular incisors.

• The Korean Journal of Malacology
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• v.32 no.1
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• pp.25-30
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• 2016

Growth-line analysis was carried out on 80 hard clam (Meretrix petechialis) from the Neolithic Age Eurwang-dong Shell Midden, Incheon, Korea, to determine the seasonality of shellfish collection and site occupation. Growth increments and the marginal index (MI) of the specimens were examined. And then the marginal index was compared to the monthly MI of modern specimens under the assumption that the growth pattern was the same as it is today. MI of the archaeological specimens ranged from 0.12 to 1.55 and was divided into four categories: < 0.63, spring; 0.63-0.76, summer; 0.76-0.89, fall; $${\geq}_-0.89$$, winter collection. As a result, 57 specimens (71.25%) of 80 specimens represented spring, 8 (10.0%) summer, 3 (3.75%) fall and 12 (15.0%) winter collection. The result indicates that shellfish could be collected year-round at the site with an emphasis on spring. Based on the size distribution of shells and the content of the midden, however, it seems that the midden site was not occupied permanently throughout the year but was used repeatedly but temporally for shellfish gathering and processing.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.16 no.3
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• pp.11-22
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• 2012

Objectives: The aim of this study was to elucidate the relationship between pulse types measured by pulse analyzer and several factors including smoking, drinking alcohol, exercises etc. Methods: The subjects were 71 persons who were tested by oriental health examination. A self-reported questionnaire was used to gather age, smoking, drinking alcohol, exercise state and gender. The pulse types were measured by DMP 1000. The index of stress and fatigue were measured by SA 3000. We analyzed the frequency of pulse types according to gender, ages, smoking, drinking alcohol etc by chi-square test with SPSS ver. 19.0. Results: In the main pulse types, there were significant differences according to age(p<0.05) and marginal differences according to drinking alcohol(p<0.1). In the secondary pulse types, there were marginal differences according to exercise, ages. But there was no significant differences according to gender, smoking, body mass index (BMI), accelerated photoplethysmography (APG) feature, stress and fatigue. Conclusions: This study suggests that the pulse types are affected by drinking alcohol, ages, exercise.