• Journal of Periodontal and Implant Science
• /
• v.53 no.3
• /
• pp.233-244
• /
• 2023

Purpose: An implant-supported prosthesis consists of an implant fixture, an abutment, an internal screw that connects the abutment to the implant fixture, and the upper prosthesis. Numerous studies have investigated the microorganisms present on the implant surface, surrounding tissues, and the subgingival microflora associated with peri-implantitis. However, there is limited information regarding the microbiome within the internal screw space. In this study, microbial samples were collected from the supragingival surfaces of natural teeth, the peri-implant sulcus, and the implant-abutment screw hole, in order to characterize the microbiome of the internal screw space in healthy subjects. Methods: Samples were obtained from the supragingival region of natural teeth, the peri-implant sulcus, and the implant screw hole in 20 healthy subjects. DNA was extracted, and the V3-V4 region of the 16S ribosomal RNA was sequenced for microbiome analysis. Alpha diversity, beta diversity, linear discriminant analysis effect size (LEfSe), and network analysis were employed to compare the characteristics of the microbiomes. Results: We observed significant differences in beta diversity among the samples. Upon analyzing the significant taxa using LEfSe, the microbial composition of the implant-abutment screw hole's microbiome was found to be similar to that of the other sampling sites' microbiomes. Moreover, the microbiome network analysis revealed a unique network complexity in samples obtained from the implant screw hole compared to those from the other sampling sites. Conclusions: The bacterial composition of the biofilm collected from the implant-abutment screw hole exhibited significant differences compared to the supra-structure of the implant. Therefore, long-term monitoring and management of not only the peri-implant tissue but also the implant screw are necessary.

• The Journal of Korean Academy of Prosthodontics
• /
• v.36 no.2
• /
• pp.258-272
• /
• 1998

This investigation evaluated patients who received Steri-Oss implants from the Dental Hospital of Chosun University during the period from March 1989 to August 1997. 346 fixtures of 127 patients were included in this study. The results were as follows ; 1.The follow-up period was defined as the period between the surgical placement of the implants and the last follow-up examination. The mean follow-up period was $2.17{\pm}1.21$ years. 2.The period between fixture installation and second surgery was $0.71{\pm}0.44$ years in the maxilla and $0.46{\pm}0.21$ years in the mandible. 3.The number of fixtures which were installed in the upper jaw(112) was less than that in the lower jaw(234) and in the posterior region(260) was more than in the anterior region(86). 4.The length of fixture which was most frequently used was 12 mm and least was 8mm. Screw implants were installed more than cylindrical implants. 3.8mm implant was the most common implans, followed by 4.5mm and 3.25mm. 5.The number of augmentation cases was more than that of non-augmentation cases and the rate of augmentation cases in the maxilla was more than that in the mandible. 6.Implant restorations for partial edentulos patients(94cases) were more than single- tooth implant restorations(33cases) or implant restorations for complete edentulos patients(10cases). 7.Free-standing prostheses for partially edentulous patients were more commom than any other type of connection between implants and natural teeth. 8.Plaque Index($0.95{\pm}0.74$) and Gingival Index($0.31{\pm}0.52$) were very similar around the natural teeth and reflected an acceptable level of plaque and gingivitis control. Mean value for keratinized mucosa index($1.93{\pm}1.20$) remained fairly constant around level 2(1-2 mm keratinized epithelium). 9.Patients were generally satisfied with implant in terms of comfort, function, speech and esthetics. 10.There was not a statistically significant differences in overall survial rate between implants placed in the maxilla (91.5%) and those placed in the mandible (93.8%). Fourteen implants lost before the prosthetic rehabilitation and eleven implants lost following variable periods in function after the prosthetic phase of the treatment. 11.Cause of implant failures was exfoliation or removal of fixture due to non-osseointegration before the prosthetic rehabilitation or due to fracture of fixture, masticatory pain after the prosthetic rehabilitation. 12.The survival rate of Steri-Oss implants using the Kaplan-Meier statistical analysis was 93.8% at 2 year and 86.6% at 5 year, In all cases, implant losses occured predominantly in the healing period. There was a steep decline in the rate of implant loss after the first year. 13.The survival rate of Steri-Oss implants in the anterior region was 94.8% at 2 year and 94.8% at 5 year and that in the posterior region was 92.8% at 2 year and 75.9% at 5 year. In conclusion, this study revealed a number of parameters and guidelines for achieving an optimal success rate in osseointegration.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.45 no.3
• /
• pp.354-362
• /
• 2018

Periogen is a new caries activity test using real-time polymerase chain reaction. The aim of this study was to assess the validity of Periogen by evaluating the correlation with dmft, dmfts indices and comparing with Cariview and caries risk assessment tool (CAT). 83 children under 6 participated in this study. Dmft, dmfts indices and CAT were collected through an examination of oral health status. Plaque samples for Periogen and Cariview were collected and manipulated according to the manufactures' instructions. The correlation coefficient of Periogen, Cariview and CAT with the dmfts index were 0.38, 0.56 and 0.66 in each (p < 0.01). The sensitivity of Periogen, Cariview and CAT were 43%, 76% and 95% and specificity were 80%, 72% and 74% respectively. Area under curve under the receiver operating characteristic curves in each method indicated 0.69, 0.81 and 0.85. CAT and Cariview were more effective in evaluation the risk of dental caries than Periogen so far. To be used Periogen clinically, more improvements for higher validity were needed.

• Journal of Periodontal and Implant Science
• /
• v.32 no.3
• /
• pp.615-630
• /
• 2002

Various long-term studies have shown that titanium implants as abutments for different types of prostheses have become a predictable adjunct in the treatment of partially or fully edentulous patients. The continuous exposure of dental implants to the oral cavity with all its possible contaminants creates a problem. A lack of attachment, together with or caused by bacterial insult, may lead to peri-implantitis and eventual implant failure. Removal of plaque and calculus deposits from dental titanium implants with procedures and instruments originally made for cleaning natural teeth or roots may cause major alterations of the delicate titanium oxide layer. Therefore, the ultimate goal of a cleaning procedure should be to remove the contaminants and restore the elemental composition of the surface oxide without changing the surface topography and harming the surrounding tissues. Among many chemical and mechanical procedure, air-powder abrasive have been known to be most effective for cleaning and detoxification of implant surface. Most of published studies show that the dental laser may be useful in the treatment of pen-implantitis. $CO_2$ laser and Soft Diode laser were reported to kill bacteria of implant surface. The purpose of this study was to obtain clinical guide by application these laser to implant surface by means of Non-contact Surface profilometer and X-ray photoelectron spectroscopy(XPS) with respect to surface roughness and atomic composition. Experimental rough pure titanium cylinder models were fabricated. All of them was air-powder abraded for 1 minute and they were named control group. And then, the $CO_2$ laser treatment under dry, hydrogen peroxide and wet condition or the Soft Diode laser treatment under Toluidine blue O solution condition was performed on the each of the control models. The results were as follows: 1. Mean Surface roughness(Ra) of all experimental group was decreased than that of control group. But it wasn't statistically significant. 2. XPS analysis showed that in the all experimental group, titanium level were decreased, when compared with control group. 3. XPS analysis showed that the level of oxygen in the experimental group 1, 3($CO_2$ laser treatment under dry and wet condition) and 4(Soft Diode laser was used under toluidine blue O solution) were decreased, when compared with control group. 4. XPS analysis showed that the atomic composition of experimental group 2($CO_2$ laser treatment under hydrogen peroxide) was to be closest to that of control group than the other experimental group. From the result of this study, this may be concluded. Following air-powder abrasive treatment, the $CO_2$ laser in safe d-pulse mode and the Soft Diode laser used with photosensitizer would not change rough titanium surface roughness. Especially, $CO_2$ laser treatment under hydrogen peroxide gave the best results from elemental points of view, and can be used safely to treat peri-implantitis.

• The Journal of the Korean dental association
• /
• v.47 no.12
• /
• pp.830-837
• /
• 2009

Purpose : The purpose of this study was to evaluate the clinical effect of Vitamin C, Vitamin E, lysozyme, carbazochrome complex medicine($IGATAN^{(R)}$) for periodontal disease. Material and Methods : The study was performed by double blinded, ramdomized method. Forty two subjects diagnosed as chronic incipient or moderate periodontitis at department of periodontology, Yonsei Dental Hospital were included in the study. This study was approved by Institutional Review Board, Yonsei University Hospital. All subjects received scaling at their first examination and second examination was scheduled after 2 weeks. At second examination, periodontal parameters such as plaque index(PI), gingival index(GI), probing depth(PD), bleeding on probing(BOP), gingival recession(GR) and clinical attachment level(CAL) were recorded(Baseline) with prescription of Vitamin C, Vitamin E, lysozyme, carbazochrome complex($IGATAN^{(R)}$) (Experimental group 23 subjects) or placebo medicine(Control group; 19 subjects). The subjects were recalled after 4 weeks for periodontal parameters measurement. Results : In the experimental groups, PI, GI, CAL and BOP scores were significantly reduced at 4 weeks compared to baseline. A statistically significant decrease in or and BOP scores were observed in the experimental group compared to the control group. Conclusion : It can be concluded that Vitamin C, Vitamin E, lysozyme, carbazochrome complex medicine($IGATAN^{(R)}$) have an effect in reducing gingival bleeding and improving periodontal inflammatory condition inchronic incipient- moderate periodontitis.

• Journal of Periodontal and Implant Science
• /
• v.30 no.4
• /
• pp.707-727
• /
• 2000

매식된 인공치아의 성공을 위해서는 적절한 교합과 수동적 적합성을 갖는 보철물의 제작과 구강내 노출 직후부터의 세균성 치태조절이 요구된다. 본 연구는 전처리(passivation과 tridodecyl - methyl - ammonium chloride(TDMAC) 처리)가 다른 타이타늄 표 면에 chlorhexidine varnish와 테트라사이클린 을 도포시 약제의 방출역학을 알아보고 구강내 치태형성의 억제정도를 평가하기 위하여 시행 되었다. 이를 위해 방출용액으로 인산완충액 성분의 인조타액을 1일${\sim}$1개월간 매일 교환하여 약제농도를 측정하고 타이타늄 박막에 잔류한 약제 활성을 측정하였으며 항균제 도포한 타이타늄 원판을 부착한 장치를 구강내 위치시킨 1일${\sim}$3주 후 원판을 제거하여 주사전자현미경으로 세균 부착상을 관찰하였다. 테트라사이클린은 TDMAC 처리된 표면에서 $10{\sim}18$일까지 유효농도로 방출되었고 표면의 유효 항균 활성은 $3{\sim}4$주간 유지되었으며, chlorhexidine varnish 도포 시에는 TDMAC 전처리시 초기에 $3{\sim}7$일 간 증가한 유효 항균 활성을 방출하여 매식지대치 등에 이러한 항균제도포 시 매식치 주위환경에 항균활성 공급원으로 작용할 수 있음을 보였다. 주사현미경적 관찰시 모든 타이타늄 표면에서 구강내 위치 30분 후에는 세균이 부착되어 있지 않고 타액 단백질 성분에서 유래한 것으로 보이는 피막물질이 표면을 부분 또는 전면에 걸쳐 덮고 있었다. 구강내 노출 2시간 후 항균제 미도포 표본들에는 약간의 구균이 단층으로, $1{\sim}3$일 후에는 부분적으로 두꺼운 세균층을 형성하였고 7일 후에는 표면전체에 걸쳐 세균층이 덮여있었으며 주로 구균과 약간의 간균이 주종을 이루었다. 항균제 도포시 구강내 노출 1주일 이전까지는 미도포군에 비해 치태형성이 지연되는 경향을 보였지만 2주 이후에는 세균 수나 치태형성 양상이 유사하였다. 이 연구로부터 항균제 도포시 1주일 이전의 초기 치태형성을 감소시킬 수 있음을 알 수 있었으며 이러한 연구결과는 타이타늄 임프란트 지대치 표면에 항균제의 도포가 임상적으로 유용할 수 있음을 시사하였다.

• Applied Biological Chemistry
• /
• v.51 no.1
• /
• pp.84-87
• /
• 2008

In this research, we screened for glucosyltransferase (GTase) inhibitors that effectively prevent the dental caries from 420 kinds of boiled water extracts of herbs and wild plants and searched for GTase inhibitory activities. Among them, 13 kinds of hot water extracts had high GTase inhibitory activities and especially, we focused on Foeniculum vulgare which showed the highest inhibitory activity on GTase. The boiled water extract of F. vulgare was stable at high temperature and showed as a mixed type of competitive and uncompetitive inhibition kinetic behavior. It did not have antibacterial effect on Streptococcus mutans and had inhibitory activity on GTase. Specially, in the clinical trial, the group treated by boiled water extract of F. vulgare showed more decrease of plague index at 4.8 point than untreated group. These results suggested that boiled water extract of F. vulgare can effectively suppress the plague formation as it inhibits the GTase activity.

• Journal of the Korea Convergence Society
• /
• v.10 no.5
• /
• pp.333-340
• /
• 2019

The purpose of this study was to analyze the effectiveness of oral health education using Qraycam. The study materials used oral hygiene examination, oral health attitude and oral health behavior scores, and compared their pre and post results. This study was a pre-post test design for a single group. The research period was from September to mid-December, 2018. The subjects of the study were 33 participants who visit for the class and 33 students for the survey of education preference. The data analysis used IBM SPSS 24.0 Ver, a significant level was 0.05. As a result, O' Leary index and halitosis as oral hygiene examination were significantly reduced according to intervention pre and post using Qraycam (p<.001). The oral health attitude and oral health behavior score were statistically significantly high according to intervention pre and post using Qraycam (p<.001). The satisfaction level was significantly high when using Qraycam among students' preference for education methods in the categories "useful in oral health education" and "a good ability to recognize and determine plaque" (p<.001). In conclusion, oral health education using Qraycam in dental clinics will be a way to improve oral health education effects for dental hygienists.

• Journal of Korean society of Dental Hygiene
• /
• v.21 no.4
• /
• pp.337-348
• /
• 2021

Objectives: To determine the usefulness of MiriChek^TM Oral Bacter as compared to traditional clinical methods in the periodontal assessment of dogs with and without periodontitis. Methods: In this study, 61 dogs were clinically examined using the MiriChek^TM Oral Bacter test kit, and information regarding breed, age (months), sex, weight, presence of disease, and periodontitis stage was recorded. The test used a sample of supragingival plaque from the upper left premolar of the dogs. Results: This study included 30 and 31 dogs with and without periodontitis, respectively. Periodontitis was more common in older dogs than in younger dogs. The average positive and negative sensitivity rates of the MiriChek^TM Oral Bacter test kit were 73.3% and 80.7%, respectively, and were both strongly correlated with the severity of periodontitis. Conclusions: The findings of this study encourage the use of new diagnostic assist test kits, such as MiriChek^TM Oral Bacter, for appropriately detecting and diagnosing periodontal disease in dogs.

• Journal of dental hygiene science
• /
• v.13 no.4
• /
• pp.501-509
• /
• 2013

The purpose of the study is to confirm the effect of the oral health management program in exemplary kindergartens for prevent the dental caries. The study performs the survey on the parents about the changes in the oral health behaviors after the oral health education in April 2012 and measures the patient hygiene performance (PHP) index before the education, after the education and 3 weeks after the education to assess the removal capability to plaque on the teeth surface for the children. The analysis is performed on 130 people who join the program and respond the survey. There is no change in the behavior related to the tooth brushing of children after the oral health education. No change is found from the interest in the oral health education (p>0.05) but the recognition in the importance of the tooth positively change, as well as recognition of the tooth brushing method and the reaction to recommending to tooth brushing. The PHP index of children is significantly improved from 3.87 before the education through 2.71 after the education and 3.27 3 weeks after the education (p<0.001). The observation from the patents shows that their children have interest in preventing the cavities including 33.1% after having xylitol and 60.7% after the oral health education. In conclusion, the study confirms the effect of the oral health management program in exemplary kindergartens to prevent the cavities, meaning that it is required to activate the programs and keep implementing the programs including providing xylitol and education for teachers, parents and children to habituate the oral health behavior of the children and completely learn toothbrushing method under continuous management and reeducation.