Syngcuk Kim

Long-term follow-up of cases considered healed one year after apical microsurgery.

A previous report demonstrated 96.8% healing within 1 yr after apical surgery was performed with the surgical operating microscope and Super-EBA as the root-end filling material. The purpose of this paper is to report on the long-term follow-up of those cases that were considered healed at the short term. Clinical examinations were made and radiographs were evaluated 5 to 7 yr after the case had first been considered healed. Criteria for determining healed cases were the same as those used in the first report. Of the 59 roots evaluated, 54 (91.5%) remained healed, whereas 5 (8.5%) showed evidence of apical deterioration.

Biologic properties of eugenol and zinc oxide-eugenol. A clinically oriented review.

Eugenol-containing dental materials are frequently used in clinical dentistry. When zinc oxide-eugenol (ZOE) is applied to a dentinal cavity, small quantities of eugenol diffuse through the dentin to the pulp. Low concentrations of eugenol exert anti-inflammatory and local anesthetic effects on the dental pulp. Thus use of ZOE temporary filling may facilitate pulpal healing; on the other hand, high eugenol concentrations are cytotoxic. Direct application of eugenol to pulp tissue may result in extensive tissue damage. The ability of ZOE-based endodontic sealers to influence periapical tissue healing is considered in view of eugenols anti-inflammatory and toxic properties.

Short-term observation of the results of endodontic surgery with the use of a surgical operation microscope and super-EBA as root-end filling material

Observations were made on the success of endodontic surgery with microsurgical techniques using Super-EBA cement as a root-end filling material. Ninety-four cases were treated by a single clinician over a period of 1 yr and 2 months. All surgical procedures were performed under a surgical operation microscope at magnifications of ×3 to ×26. Recall radiographs were taken at 3-month intervals over a 12-month period until the lamina dura was completely restored or the case had clinically failed. The radiographic success of the 94 cases was 96.8%, and the average time for lesions to heal was 7.2 months.

Outcome of endodontic surgery: a meta-analysis of the literature--part 1: Comparison of traditional root-end surgery and endodontic microsurgery.

INTRODUCTION The aim of this study was to investigate the outcome of root-end surgery. The specific outcome of traditional root-end surgery (TRS) versus endodontic microsurgery (EMS) and the probability of success for comparison of the 2 techniques were determined by means of meta-analysis and systematic review of the literature. METHODS An intensive search of the literature was conducted to identify longitudinal studies evaluating the outcome of root-end surgery. Three electronic databases (Medline, Embase, and PubMed) were searched to identify human studies from 1966 to October 2009 in 5 different languages (English, French, German, Italian, and Spanish). Relevant articles and review papers were searched for cross-references. Five pertinent journals (Journal of Endodontics, International Endodontic Journal, Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontics, Journal of Oral and Maxillofacial Surgery, International Journal of Oral and Maxillofacial Surgery) were individually searched back to 1975. Three independent reviewers (S.S., M.K., and F.S.) assessed the abstracts of all articles that were found according to predefined inclusion and exclusion criteria. Relevant articles were acquired in full-text form, and raw data were extracted independently by each reviewer. Qualifying papers were assigned to group TRS or group EMS. Weighted pooled success rates and relative risk assessment between TRS and EMS were calculated. A comparison between the groups was made by using a random effects model. RESULTS Ninety-eight articles were identified and obtained for final analysis. In total, 21 studies qualified (12 for TRS [n = 925] and 9 for EMS [n = 699]) according to the inclusion and exclusion criteria. Weighted pooled success rates calculated from extracted raw data showed 59% positive outcome for TRS (95% confidence interval, 0.55-0.6308) and 94% for EMS (95% confidence interval, 0.8889-0.9816). This difference was statistically significant (P < .0005). The relative risk ratio showed that the probability of success for EMS was 1.58 times the probability of success for TRS. CONCLUSIONS The use of microsurgical techniques is superior in achieving predictably high success rates for root-end surgery when compared with traditional techniques.

Neurovascular interactions in the dental pulp in health and inflammation

The two key components in pulpal inflammation are microcirculation and sensory nerve activity. With advancement of techniques they can be measured simultaneously in the same tooth. Excitation of A-delta fibers seems to have an insignificant effect on pulpal blood flow (PBF), whereas C fiber activation causes an increase in PBF. This C fiber-induced PBF increase is caused by neurokinins, especially substance P, which is released from the C fiber nerve terminals. Manipulation of PBF has varying effects on sensory nerve activity. An increase in PBF causes excitation of both A-delta and C fibers via an increase in tissue pressure, whereas flow reduction has an inhibitory effect on A-delta fibers, but no discernible effect on C fiber activity. Understanding of this complex neurovascular relationship in the pulp, especially given the fact that the pulp is in a low compliance system, is prerequisite to more comprehensive characterization of pulpal inflammation.

Incidence and position of the canal isthmus. Part 1. Mesiobuccal root of the maxillary first molar

The mesiobuccal roots of 50 randomly selected maxillary first molars were examined to assess the incidence and position of the canal isthmus. Transverse serial sections of the apical 6 mm of each root were prepared in 1-mm increments. The apical side of each section was stained with methylene blue dye, viewed with a surgical operating microscope, and videotaped. Forty percent of the roots had one canal, whereas 60% had two canals. None of the sections had more than two main canals. The incidence of an isthmus was highest in the apical 3- to 5-mm levels. In teeth that had two canals, the 4-mm sections contained a complete or partial isthmus 100% of the time. The concept of a partial isthmus was presented. Failure to deal with the isthmus may explain why some posterior teeth do not heal completely following endodontic surgery.

A Review of Factors Influencing Treatment Planning Decisions of Single-tooth Implants versus Preserving Natural Teeth with Nonsurgical Endodontic Therapy

One of the major issues confronting the contemporary dental clinician is the treatment decision between extracting a tooth with placement of a dental implant or preserving the natural tooth by root canal treatment. The factors that dictate the correct selection of one procedure over the other for each particular case are not yet established by randomized controlled studies. The aim of this review is to evaluate key factors allowing the clinician to make clinical decisions on the basis of the best evidence and in the patients best interests. General considerations are discussed that will help the reader analyze clinical studies focused on this problem. Importantly, the major studies published to date indicate that there is no difference in long-term prognosis between single-tooth implants and restored root canal-treated teeth. Therefore, the decision to treat a tooth endodontically or to place a single-tooth implant should be based on other criteria such as prosthetic restorability of the tooth, quality of bone, esthetic demands, cost-benefit ratio, systematic factors, potential for adverse effects, and patient preferences. It can be concluded that endodontic treatment of teeth represents a feasible, practical, and economical way to preserve function in a vast array of cases and that dental implants serve as a good alternative in selected indications in which prognosis is poor.

Prospective Clinical Study Evaluating Endodontic Microsurgery Outcomes for Cases with Lesions of Endodontic Origin Compared with Cases with Lesions of Combined Periodontal–Endodontic Origin

The aim of this study was to evaluate the outcomes of endodontic microsurgery by comparing the healing success of cases having a lesion of endodontic origin compared with cases having a lesion of combined endodontic-periodontal origin. Data were collected from patients in the Department of Conservative Dentistry, Dental College, Yonsei University, Seoul, Korea between March 2001 and June 2005. A total number of 263 teeth from 227 patients requiring periradicular surgery were included in this study. Patients were recalled every 6 months for 2 years and every year thereafter to assess clinical and radiographic signs of healing. A recall rate of 73% (192 of 263 patients) was obtained. The successful outcome for isolated endodontic lesions was 95.2%. In endodontic-periodontal combined lesions, successful outcome was 77.5%, suggesting that lesion type (ABC vs DEF) had a strong effect on tissue and bone healing.

Outcome of Endodontic Surgery: A Meta-analysis of the Literature—Part 2: Comparison of Endodontic Microsurgical Techniques with and without the Use of Higher Magnification

INTRODUCTION The aim of this study was to investigate the outcome of root-end surgery. It identifies the effect of the surgical operating microscope or the endoscope on the prognosis of endodontic surgery. The specific outcomes of contemporary root-end surgery techniques with microinstruments but only loupes or no visualization aids (contemporary root-end surgery [CRS]) were compared with endodontic microsurgery using the same instruments and materials but with high-power magnification as provided by the surgical operating microscope or the endoscope (endodontic microsurgery [EMS]). The probabilities of success for a comparison of the 2 techniques were determined by means of a meta-analysis and systematic review of the literature. The influence of the tooth type on the outcome was investigated. METHODS A comprehensive literature search for longitudinal studies on the outcome of root-end surgery was conducted. Three electronic databases (ie, Medline, Embase, and PubMed) were searched to identify human studies from 1966 up to October 2009 in 5 different languages (ie, English, French, German, Italian, and Spanish). Review articles and relevant articles were searched for cross-references. In addition, 5 dental and medical journals (ie, Journal of Endodontics, International Endodontic Journal, Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontics, Journal of Oral and Maxillofacial Surgery, and International Journal of Oral and Maxillofacial Surgery) dating back to 1975 were hand searched. Following predefined inclusion and exclusion criteria, all articles were screened by 3 independent reviewers (S.B.S., M.R.K., and F.C.S.). Relevant articles were obtained in full-text form, and raw data were extracted independently by each reviewer. After agreement among the reviewers, articles that qualified were assigned to group CRS. Articles belonging to group EMS had already been obtained for part 1 of this meta-analysis. Weighted pooled success rates and a relative risk assessment between CRS and EMS overall as well as for molars, premolars, and anteriors were calculated. A random-effects model was used for a comparison between the groups. RESULTS One hundred one articles were identified and obtained for final analysis. In total, 14 studies qualified according to the inclusion and exclusion criteria, 2 being represented in both groups (7 for CRS [n = 610] and 9 for EMS [n = 699]). Weighted pooled success rates calculated from extracted raw data showed an 88% positive outcome for CRS (95% confidence interval, 0.8455-0.9164) and 94% for EMS (95% confidence interval, 0.8889-0.9816). This difference was statistically significant (P < .0005). Relative risk ratio analysis showed that the probability of success for EMS was 1.07 times the probability of success for CRS. Seven studies provided information on the individual tooth type (4 for CRS [n = 457] and 3 for EMS [n = 222]). The difference in probability of success between the groups was statistically significant for molars (n = 193, P = .011). No significant difference was found for the premolar or anterior group (premolar [n = 169], P = .404; anterior [n = 277], P = .715). CONCLUSIONS The probability for success for EMS proved to be significantly greater than the probability for success for CRS, providing best available evidence on the influence of high-power magnification rendered by the dental operating microscope or the endoscope. Large-scale randomized clinical trials for statistically valid conclusions for current endodontic questions are needed to make informed decisions for clinical practice.

Hypersensitive teeth: desensitization of pulpal sensory nerves.

Tooth hypersensitivity to various stimuli is an age-old complaint. The exact causes and their physiological mechanisms are not well understood. It is probable that a transient derangement of pulpal sensory nerves is involved. In this article, results of many years of animal and human electrophysiological experiments of pulpal sensory nerve activity are reported.