• Journal of Periodontal and Implant Science
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• 제52권1호
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• pp.77-87
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• 2022

Purpose: This pilot study assessed the immediate in vivo effect of high peak pulse power neodymium-doped yttrium aluminum garnet (Nd:YAG) laser monotherapy on selected red/orange complex periodontal pathogens in deep human periodontal pockets. Methods: Twelve adults with severe periodontitis were treated with the Laser-Assisted New Attachment Procedure (LANAP®) surgical protocol, wherein a free-running, digitally pulsed, Nd:YAG dental laser was used as the initial therapeutic step before mechanical root debridement. Using a flexible optical fiber in a handpiece, Nd:YAG laser energy, at a density of 196 J/cm² and a high peak pulse power of 1,333 W/pulse, was directed parallel to untreated tooth root surfaces in sequential coronal-apical passes to clinical periodontal probing depths, for a total applied energy dose of approximately 8-12 joules per millimeter of periodontal probing depth at each periodontal site. Subgingival biofilm specimens were collected from each patient before and immediately after Nd:YAG laser monotherapy from periodontal pockets exhibiting ≥6 mm probing depths and bleeding on probing. Selected red/orange complex periodontal pathogens (Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia/nigrescens, Fusobacterium nucleatum, Parvimonas micra, and Campylobacter species) were quantified in the subgingival samples using established anaerobic culture techniques. Results: All immediate post-treatment subgingival biofilm specimens continued to yield microbial growth after Nd:YAG laser monotherapy. The mean levels of total cultivable red/orange complex periodontal pathogens per patient significantly decreased from 12.0% pretreatment to 4.9% (a 59.2% decrease) immediately after Nd:YAG laser monotherapy, with 3 (25%) patients rendered culture-negative for all evaluated red/orange complex periodontal pathogens. Conclusions: High peak pulse power Nd:YAG laser monotherapy, used as the initial step in the LANAP® surgical protocol on mature subgingival biofilms, immediately induced significant reductions of nearly 60% in the mean total cultivable red/orange complex periodontal pathogen proportions per patient prior to mechanical root instrumentation and the rest of the LANAP® surgical protocol.

• 대한소아치과학회지
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• 제27권1호
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• pp.45-53
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• 2000

Enamel microabrasion은 염산과 연마제를 사용하여 치아의 착색을 제거하는 술식으로서, 그 효과는 법랑질 표층에 국한된다. Enamel microabrasion으로 모든 착색이 치료 가능한 것은 아니므로, 착색이 깊을 경우에는 microabrasion 후에도 제거되지 않고 남은 착색부위를 광중합 복합레진을 사용해 수복할 것이 권장된다. 본 연구의 목적은 enamel microabrasion의 방법과 시간이 법랑질에 대한 복합레진의 전단결합강도에 미치는 영향을 조사하는 것이었다. 아무런 처치도 하지 않은 대조군을 1군으로 하였고, 18% 염산과 fine pumice의 혼합물을 hand applicator로 치면에 5초씩 5, 10회 적용시킨 것을 각각 2, 3군으로 하였다. 10% 염산과 연마제의 혼합물인 기성품 PREMA를 10 : 1 gear reduction handpiece로 20초씩 5, 10회 적용시킨 것을 각각 4, 5군으로 하였다 여기에 37% 인산으로 부식 후 복합레진을 결합시켜 thermocycling 후 전단결합강도를 측정하여 다음과 같은 결론을 얻었다. 1. 2군이 가장 높은 결합강도$(24.36{\pm}3.34MPa)$를 나타내었고, 3군이 가장 낮은 결합강도$(19.35{\pm}3.43MPa)$를 보였다. 전단결합강도는 2>4>5>1>3군의 순서로 감소하였다. 2. 2군은 1군과 3군보다 통계학적으로 유의성 있게 높은 결합강도를 나타내었다(p<0.05). 3. 염산과 pumice로 enamel microabrasion을 시행한 2, 3군과 PREMA를 사용한 4, 5군 사이에는 유의한 결합강도의 차이가 없었다(p>0.05). 4. 파절면 검사에서, adhesive failure는 3, 4군에서 나타났고, cohesive failure는 1, 2, 3, 4군에서 관찰되었다. 5군에서는 mixed failure만이 관찰되었다. 5. SEM 관찰에서, 염산과 pumice로 enamel microabrasion을 시행한 2, 3군에서는 인산으로 부식한 것과 비슷한 표면 양상이 관찰되었고, PREMA로 처리한 4, 5군에서는 1군과 흡사한 매끈한 표면양상이 관찰되었다. 각 군의 시편을 인산으로 부식시킨 다음에는 전형적인 산부식 후의 표면양상이 관찰되었고, 군간 별다른 차이가 없었다.

• 대한소아치과학회지
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• 제28권1호
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• pp.32-44
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• 2001

Er : YAG 레이저의 상아질 삭제효과와 이에 따른 온도변화를 평가하고자 발거된 소구치와 대구치로 상아세관내 조직액과 치수내압을 유지할 수 있는 상아질 시편을 제작하고 $2.94{\mu}m$의 pulsed Er : YAG 레이저(SDL-300EN, 삼성전자, 한국)를 handpiece형의 전달계를 이용한 비접촉식 방법으로 조사세기, pulse repetition rate, 조사시간, 물 분사여부 등의 조사조건을 달리하여 상아질 면에 조사하고 이때의 삭제량과 상아질 두께에 따른 온도변화, 그리고 삭제형태를 조사, 분석하여 다음과 같은 결과를 얻었다. 1. 레이저 조사세기와 pulse repetition rate가 클수록, 그리고 조사시간이 길수록 삭제량이 증가되었다(P<0.05). 그러나 5Hz의 pulse repetition rate에서는 조사시간에 따른 삭제량의 차이가 크지 않았다. 2. 삭제된 와동은 비교적 변연부가 명확하고 깨끗하였으며 와동의 바닥은 원추형이였으며 부드러웠다. 조사세기와 pulse repetition rate가 클수록, 그리고 조사시간이 길수록 와동의 상부 직경이 넓었으며 150mJ, 5Hz, 5sec에서는 와동변연부에 약간의 crack이 관찰되었다. 3. 레이저 조사세기와 pulse repetition rate가 클수록, 그리고 조사시간이 길수록 상아질의 온도가 더 많이 상승하였으며 시편의 두께가 두꺼울수록 온도상승이 적었다(P<0.05). 4. 물을 분사하며 레이저를 조사할 경우 물을 분사하지 않은 경우에 비해 온도상승이 매우 감소되었다(P<0.05). 이상의 결과를 종합해 볼 때 Er : YAG 레이저를 상아질에 조사할 경우 와동의 형태가 명확하고 물을 분사할 경우 온도상승이 많이 유발되지 않으므로써 삭제력이 좋고 치수에 유해작용이 없는 것으로 생각된다. 향후 임상에서 치질을 제거하는데 효율적으로 이용되기 위해서는 더욱 크고 이에 따른 온도상승을 최소로 할 수 있는 조사 시스템 및 방법에 대한 연구가 계속적으로 이루어져야 할 것으로 사료된다.

• Restorative Dentistry and Endodontics
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• 제31권6호
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• pp.477-484
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• 2006

학생들이 사용한 세 가지 NiTi file systems (ProFile$^{(R)}$, Hero Shaper$^{(R)}$, K3$^{TM}$)을 사용하여 성형한 모형 근관의 apical terminus width를 비교하여 flute angle 및 pitch 혹은 radial land가 screw-in effect에 미치는 효과를 알아보고자 하였다. NiTi file의 사용 경험이 없는 부산대학교 치과대학 4학년 학생 50명이 세 종류의 NiTi file systems- Pro File$^{(R)}$ (Dentsply Maillefer, Ballaigues, Switzerland), K3$^{TM}$ (SybronEndo, Glendora, France), Hero Shaper$^{\circledR}$(Micromega, Besancon, France)-을 사용하여 각 system으로 하나의 근관씩, 모두 150 개의 레진 블락 근관모형 (Endo Training Bloc; Dentsply Maillefer, Ballaigues, Switzerland)을 16 : 1 감속 handpiece를 장착한 electric motor (Tecnika ATR, Pistola, Italy)를 사용하여 300 rpm의 속도에서 torque는 30 (Tecnikamotor setting value)으로 성형하였다. 스캐너로 근관 성형 전 후 이미지를 채득하여 중첩한 후 근단부의 최종 폭경을 측정하였다. 통계분석은 one-way ANOVA와 95% 신뢰도의 Scheffe's multiple range test로 사후 검증하였다. ProFile$^{(R)}$의 근관 성형 후 근단부의 폭이 Hero Shaper$^{(R)}$ and K3$^{TM}$에 비해 통계학적으로 유의하게 작았다. 본 연구의 결과에서 근단부의 과도한 확대가 variable pitch와 helical angle를 가진active file에 비해 con-stant pitch와 helical angle을 가짐에도 불구하고 radial land를 가진passive file에서 적게 나타났다. 이 결과로 추정해 볼 때, variable pitch와 helical angle보다는 근본적으로 radial land가 screw-in effect의 예방에 더 큰 역할을 하는 것으로 추정될 수 있다 따라서 NiTi file의 사용 경험이 없는 초심자의 경우 근단부 폭경의 유지능력이 좋은 ProFile$^{(R)}$의 사용이 추천된다.

• 구강회복응용과학지
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• 제27권1호
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• pp.91-97
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• 2011

본 연구의 목적은 근관치료용 무선전기모터인 X-Smart의 지속적인 사용 시, 배터리전원과 AC 어댑터 전원일 때의 RPM의 유지를 평가하고자 하였다. X-Smart (Dentsply Maillefer, Ballaigues, Switzerland) 신품 5대를 사용하였다. 본체에 연결한 핸드피스를 바이스에 고정하고, RPM의 측정을 위한 반사지를 붙인 Disk를 장착하였다. 비접촉식 RPM측정기인 TM-5000을 사용하여 RPM을 측정하였다. 배터리 전원시의 RPM과 AC 어댑터 전원시의 RPM을 5분마다 180분에 걸쳐 측정하였고 각 전기모터마다 3회씩 반복하였다. $SPSS^{TM}$ 14.0을 이용하여 2요인 반복측정분석을 통해 각 전원별 전기모터에 따른 RPM 변화량과 전원의 종류에 따른 RPM 변화량의 상관관계를 95% 유의 수준에서 비교하였다. 전원의 종류와 관계없이 같은 전원에서 각 기기별 RPM 변화량은 유의한 차이를 보이지 않았고, 전원의 종류에 따른 RPM 변화량의 차이는 90분 이후의 측정치에서 점진적으로 증대되는 것이 관찰되어지나 통계학적으로 유의한 차이는 보이지 않았다. 이상의 결과로, 배터리 전원의 무선전기모터로서의 X-Smart를 180분 이내로 연속사용 한다면, 신뢰성 있는 RPM 유지를 얻어 안전한 임상사용이 가능하리라 생각된다.

• 대한치과보철학회지
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• 제36권1호
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• pp.64-80
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• 1998

The risk of cross-contamination in dental clinic is very high. Those who are engaged in dental clinic are exposed to various microorganisms in saliva and blood of patient. Potential possibility of cross-contamination of patient to patient, patient to dentist, dentist to laboratory technician always exist, which is important in the view of public health. It is well known that microorganisms may cause cross-contamination by suck-back of microorganisms into the water supply line or air supply line of dental unit and sprayed back into the next patient's oral cavity. The majority of microorganisms coming from dental unit are water microorganisms from the main water supply which have colonized the tube within the units and multiplied in the relatively warm and stagnant conditions. The purpose of this study is to measure the extent of microbial contamination of dental unit and ultrasonic scaler, to evaluate that dental unit water supply is suitable for drinking water, and to assess the effect of flushing on reduction of microbial contamination of dental unit and ultrasonic scaler. In the first experiment, water samples(50ml) from 20 dental units and 10 ultrasonic scalers in Seoul National Univ. Hosp. were tested for the presence of coliform. The samples were filtered by membrane filtration technique.(Microfil system, Millipore Co. U. S. A.) The filter was then placed onto MacConkey agar plate and the plates with filter on it were incubated aerobically at $37^{\circ}C$ for 5 days. The colors and shapes of colonies were examined if those were coliform. To verify the presence of coliform, the colonies were inoculated into phenol red lactose broth and incubated aerobically at $37^{\circ}C$ for 2 days. The fomation of gas was observed. In the second experiment, water samples from 20 handpieces, 10 ultrasonic scalers and 30 A/W syringes after 0, 2, 4, 6 min. flushing respectively were taken. $200{\mu}l$ water samples were spreaded on Brain Heart Infusion agar plate and the plates were incubated aerobically at $37^{\circ}C$ for 5 days. The number of colony was counted. The results obtained were summarized as follows 1. The water from dental unit and ultrasonic scaler was not suitable for drinking water. 2. No coliform was founded in dental unit and ultrasonic scaler water supply. 3. The number of colony of dental unit and ultrasonic scaler was highest in the group of o min. flushing(p<0.05). 4. There was no statistically significant difference in the extent of microbial contamination among handpiece, ultrasonic scaler and A/W syringe (p>0.05). 5. The number of colony was lowest in the group of 4 min. flushing, but there was no statistically significant difference among 2, 4, 6 min. flushing groups.(p>0.05) 6. It is recommended to flush dental unit water line for 4 min. after use on each patient.

• 대한치과보철학회지
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• 제41권5호
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• pp.565-581
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• 2003

Statement of problem : A scientific examination and understanding of overall aspects of the natural dentition is the first step involved in making a satisfactory selection in the shade of an aesthetic prosthesis. Proper natural shade selection of the prosthetic restoration that is in harmony with the remaining dentition is as important aesthetically, as harmony of form and function in the anterior dentition. Clinically, the most commonly applied method of shade selection has been visual, but because of the subjective nature inherent to this method, shade selection results are variable and can be influenced by such factors as the technician, the type of shade guide used, and the type and intensity of the lighting. Purpose : The purpose of this study was to develop a more objective and scientific approach to examining and understanding the shade of teeth, which has in turn lead to the development of a number of shade analysis devices that present a more objective method of shade analysis. Material and Method : In this study, the shades of healthy anterior teeth were examined and analyzed using the recently developed digital shade analysis of the $ShadeScan^{TM}$ System. The study examined 80 individuals in their twenties, 40 males and 40 females, presenting 6 healthy, unrestored maxillary anterior teeth. Tooth brushing and oral prophylaxis were performed prior to evaluation. The ShadeScan handpiece was used to acquire images of the 6 maxillary anterior teeth. These images were analyzed using the Vita/Classical mode of the $ShadeScan^{TM}$ Software, and shade maps of each tooth were acquired and divided into cervical, middle, and incisal thirds. The shade distribution of each third, left and right symmetry, and gender differences were investigated and analyzed. Results : The results of the study are as follows : 1. An overwhelming majority of the examined teeth were found to possess shades belong to Group A, with the greatest variations occurring at the middle and cervical thirds of the maxillary central and lateral incisors, in both male and female subjects. 2. Canines of both male and female subjects showed left and right symmetry with uniform shade distribution of A4 and C4, while the lateral and central incisors showed left-right symmetry of the incisal 1/3 with a uniform shade distribution of A2 and A3 shades 3. No significant differences in shade distribution were seen between genders in maxillary canines, whereas maxillary central and lateral incisors showed differences at the middle and cervical thirds between male and female subjects The results of this study show that with the exception of maxillary canines, maxillary anterior teeth display a diverse shade distribution as well as gender differences. Conclusion : Clinically, when making a shade selection using the existing shade guide, one must consider the fact that even a single tooth consists of a variety of shades. The results of this study show that when selecting a shade from a number of groups is difficult, shades from A group are the most consistent with the natural shade or maxillary anterior teeth.

• Journal of Periodontal and Implant Science
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• 제26권3호
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• pp.701-713
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• 1996

The purpose of this study was to evaluate the biocompatibility of the Nd:YAG lased root surface followed by root planing and/or tetracyline-HCI(T.C.-HCI) conditioning. $30,4mm{\times}4mm$ root segments were obtained from unerupted third molars and 21, periodontally involved root segments. The treatment groups were as follows : (1) healthy root cementum surface groups : 1) control(non-treated group), 2) lased only, 3) lased/root planed, and 4) lased/T.C.-HCI. (2) diseased root cementum surface groups : 1) control(root planed only), 2) lased/root planed, and 3) lased/root planed/T.C.-HCI. The specimens were treated with a Nd:YAG laser using a $320{\mu}m$ noncontact optic fiber handpiece with an energy setting of 1.5W($114.6J/cm^2$), 2.0W($152.9J/cm^2$), 5.0W($382J/cm^2$) for one minute. The fiber was held perpendicular to the petri dish(NUNC) 2cm apart in an attempt to expose the entire root segments equally. Human gingival fibroblasts were cultured from explants of normal interdental gingival tissue obtained during third morlar extraction. The attachment assay was performed with third-generation fibroblasts. The numbers of gingival fibroblasts attached to the root surface were counted on each specimen under the light microscope, and were statistically analyzed by the oneway ANOVA followed by Tukey's test in SPSS/PC+programs. The results were as follows : 1) In healthy root cementum surfaces, lased/root planed groups exhibited a significantly increased fibroblast attachment compared to controls, lased only, and lased/T.C.-HCI groups(p<0.05), 2) In diseased root cementum surfaces, laser treatment followed by root planing and/or T.C.HCl groups exhibited a increased tendency of fibroblast attachment compared to root planed only group. The results suggest that laser treatment followed by root planing and/or T.C.-HCl would appear necessary so as to render the root surface biocompatible.

• 치과방사선
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• 제24권1호
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• pp.115-124
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• 1994

The purpose of this study was to examine the differences in representation of a globular radiopaque mass on the pantomograms and Waters' views and to compare the efficacy of periapical radiograms, pantomograms and Waters' views in detection of defects on the internal walls of the maxillary sinus. This study was performed with dried human skull. For the study of difference of radiopaque mass shadow in the two views, rubber ball with a diameter of 10㎜ was used as the experimental lesion. It was placed successively on the internal wall of the anterior, posterior, medial, lateral walls and floor of the maxillary sinus. To examine the detectability of defects for radiographic techniques, defects were formed in the anterior, posterior, medial, lateral walls, and floor of the maxillary sinus. They were formed with 0.5㎜, 0.75㎜, 1.0㎜, 2.0㎜ and 3.0㎜ sized steel round burs with a slow speed dental handpiece. By subsequently plugging the holes with zinc oxide eugenol paste, radiopaque defects were produced. After that the periapical radiograms, the pantomograms and the Waters' views were taken each and every defect. The obtained results were as follows: 1. Rubber balls placed on each internal wall of the maxillary sinus were correctly depicted on the posterior wall and the floor in case of the pantomogram, and on the anterior wall and the medial wall in case of the Waters' view. 2. On the detectability of defects for each radiographic technique, radiolucent defects were detected in different places for each technique. Periapical radiogram could detect 1.0㎜ defect on the floor of the maxillary sinus, pantomogram could detect 2.0㎜ defect on every internal wall of the maxillary sinus, and Waters' view could detect 3.0㎜ defect on the anterior wall of the maxillary sinus. 3. On the detectability of defects for each radiographic technique, radiopaque defects were detected in different places for each technique. Periapical radiogram could clearly detect 0.5㎜ defect on the floor of the maxillary sinus, pantomogram could detect 0.5㎜ defect on every internal wall of the maxillary sinus, and finally Waters' view could detect 0.5㎜defect on the anterior wall of the maxillary sinus but 0.75㎜ defect on the anterior wall, lateral wall and floor of the maxillary sinus. As the result, the periapical radiogram is the most simple and satisfactory method for investigating in the maxillary sinus. The pantomogram is suitable method for screening of changes in the maxillary sinus. And the Waters' view is available for detect of lesion in the anterior wall of the maxillary sinus. For the purpose of accurate diagnosis and evaluation of lesion in the maxillary sinus, these techniques supplement each other.

• 치위생과학회지
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• 제15권4호
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• pp.399-406
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• 2015

치과의료기관의 감염관리 수행 조사를 위해 2014년 6~7월 기간 동안 일부 지역사회 치과위생사 158명을 대상으로 기관, 감염관리자, 환자의 감염관리 수행을 자기기입식 설문조사하였다. 치과병원은 감염관리지침서 구비, 감염관리 담당자 지정, 정기감염관리 교육지원, 1인 멸균핸드피스 사용 비율은 57~74%였으나 치과의원은 13~20% 수준이었다(p<0.05). 감염관리자의 감염관리지침 인지는 치과병원 17.4%, 치과의원 5.9%였고 정기예방접종 시행은 치과병원 60.9%, 치과의원 34.1%였다(p<0.05). 환자의 손 위생 수행, 진료 전 칫솔질, 교차 감염 교육경험은 20% 미만이었고, 병력조사 협조는 90% 이상이었다(p<0.05). 감염관리 실천 상관분석 결과 기관 지원은 치과위생사 감염관리자실천, 환자감염관리협조, 개인방호실천, 진료실감염관리실천, 폐기물관리실천과 양의 상관관계를 나타내었으며 통계적으로 유의하게 분석되었다(p<0.05). 감염관리 실천을 위해 의료진, 환자, 기관의 지원과 협조가 요구되며 감염관리 관리자는 지속적인 교육을 통해 감염관리지침을 인지하고 실천할 것이 요구된다.