A nonsurgical endodontics relational research database: the initial six years of experience.

The purpose of this study was to report results of the initial six years of experience utilizing a nonsurgical root canal treatment (NSRCT) database; to compare patient characteristics, operative procedures, and patient outcomes observed in the database to those observed in other studies; and to discuss the potential benefits of a clinical endodontic database. A total of 7,372 NSRCT cases performed by endodontic residents at the University of Pennsylvania from 2000 to 2006 were evaluated. The odds ratio (OR) for caries and trauma being causative agents for NSRCT in

A comparison of LightSpeed LS1 and LightSpeed LSX NiTi rotary instruments in apical transportation and length control in simulated root canals.

In a major design change LightSpeed Technologies Inc. has replaced the U-shape blade design with a spade-shape design in LightSpeed LSX root canal rotary instruments. A double-digital radiographic technique was used to compare apical transportation (AT) and length control (LC) between the two instrument designs. Thirty simulated plastic root canals were instrumented by each rotary system. Digital radiography and AutoCAD 2007 were used to determine the central axes of files at 20, 35, 50, and 70 ISO sizes. By superimposition of central axes with a baseline at size 20, the degree of AT was measured at 0, 1, and 3 mm from working length (WL). The distance from file tips to set WL indicated any loss of LC. ANOVA test showed no significant differences between groups with respect to the degree of AT or LC. No instrument separation was noted. The results indicate that newly designed Lightspeed LSX instruments maintain the same effectiveness regarding AT and LC as that of the LightSpeed LS1 instruments.

Microscopic periradicular surgery: perioperative predictors for postoperative clinical outcomes and quality of life assessment.

The authors report on data from a self-assessment questionnaire filled out by 199 patients undergoing periradicular microscopic surgery at two private endodontic offices and at graduate endodontic clinics of the University of Pennsylvania. Regression analysis was performed using pain and swelling as dependent variables and age, sex, type of teeth, location, periapical lesion, and remedication as independent variables. Pain and swelling were significantly related to females and younger patients (p < 0.05). The results supported Etodolac as a pre- and postoperative analgesic and use of antibiotics restricted to high-risk patients. Maximum pain and swelling were reported at night and day 1 of the surgery, respectively. Generally, swelling was more often reported than pain. Surgeries in anterior maxilla were related to more pain and swelling. A majority of the patients (67%) rated surgical endodontics more pleasant than expected and found it less painful (46%) or the same (38%) as nonsurgical treatment. The results also point out that patients in general have negative beliefs and limited knowledge about periradicular surgery.

For teeth requiring endodontic treatment, what are the differences in outcomes of restored endodontically treated teeth compared to implant-supported restorations?

PURPOSE: The clinical question this systematic review aimed to answer was "What are the differences in outcomes of restored endodontically treated teeth compared to implant-supported restorations? Therefore the aim of this study was to use systematic review to compare the survival of compromised teeth restored with either root canal therapy followed by a crown, or placement of a single-tooth implant. MATERIALS AND METHODS: MEDLINE, EMBASE, and PubMed databases were searched for studies dealing with survival of single-tooth implants and restored endodontically treated teeth. A 2-step screening procedure was used to identify articles that met the inclusion/exclusion criteria. Fifty-five studies related to single-tooth implants and 13 studies related to restored root canal-treated teeth were included. The endpoint analyzed in these studies was the survival rate of the treated tooth or implant. RESULTS: The 95% confidence intervals for the pooled estimates for the single-tooth implants and restored endodontically treated teeth were found overlapping in forest plots for all follow-up periods. This indicated no significant differences in survival between restored root canal-treated teeth and single-tooth implants. CONCLUSIONS: The results of this systematic review indicate that the decision to treat a tooth endodontically or replace it with an implant must be based on factors other than the treatment outcomes of the procedures themselves. Both nonsurgical root canal therapy followed by an appropriate restoration and single-tooth implants are excellent treatment modalities for the treatment of compromised teeth.

Instrumentation and obturation of the apical third of root canals: addressing the forgotten dimension.

Modern developments in instrument design and obturation techniques have greatly improved the efficiency of conventional endodontic therapy. Nickel titanium rotary instruments allow the practitioner to prepare canals more quickly and predictably. However, apical preparations by such instruments fail to address the anatomical complexity of the root canal system. Morphologic studies consistently show that canals are mostly oval or irregular in shape; therefore, round preparations by instrumentation result in uninstrumented areas of the root canal system. This is of particular importance in the apical third and in cases of preexisting periapical pathology, where residual bacteria may reside and cause persistent infections. How beneficial are these new instrumentation and obturation techniques to the basic purpose of root canal therapy in eradicating bacteria? This article presents the shortcomings of current instrumentation and obturation techniques and offers possible solutions to improve the outcome of endodontic therapy.

A retrospective clinical study of incidence of root canal instrument separation in an endodontics graduate program: a PennEndo database study.

This study investigated the incidence of hand and rotary instrument separation (IS) in the endodontics graduate program at the University of Pennsylvania between 2000 and 2004. In 4,865 endodontic resident cases the incidence of hand and rotary IS was 0.25% and 1.68%, respectively. The odds for rotary IS were seven times more than for hand IS. The probability of separating a file in apical third was 33, and 6 times more likely when compared to coronal and middle thirds of the canals. The highest percentage of IS occurred in mandibular (55.5%) and maxillary (33.3%) molars. Furthermore, the odds of separating a file in molars were 2.9 times greater than premolars. Among the ProFile series 29 rotary instruments, the .06 taper # 5 and # 6 files separated the most. There was no significant difference in IS between the use of torque controlled versus nontorque controlled handpieces, nor between first and second year residency.

A comparison of three methods for preparing centered platforms around separated instruments in curved canals.

This study compared three methods for creating the most centered staging platform (SP) around separated instruments (SI) in curved canals. Green .04 ProFiles, notched at D(3), were separated in the apical third of 42 mesiobuccal canals of maxillary and mandibular molars. Teeth were divided into three groups. SPs were prepared in group 1 with Gates Gliddens (GG) to a size #3; group 2 with LightSpeed to a size 90; and group 3 with incrementally cut rotary .06 ProFiles to size 82. Pre- and postoperative digital radiographs were imported into AutoCAD to measure the deviation of SP from the head of the separated instrument. Pearson's correlation showed a positive relationship between deviation of the SP and the distance of the SI from the elbow of the canal. ANOVA showed that LightSpeed instruments were significantly more effective in preparing a centered staging platform around separated instruments in curved canals when compared to GG drills and ProFiles (p < 0.05).

The clinical significance and management of apical accessory canals in maxillary central incisors.

BACKGROUND: The maxillary central incisor is considered to be the least difficult subject for a clinical endodontic experience. However, the internal anatomy of maxillary central incisors can present a number of variations, including multiple accessory canals. CASE DESCRIPTION: This article highlights the clinical significance and management of accessory canals located in the apical one-third of maxillary central incisors. The authors present two case reports in which failure to detect the accessory canals led to root canal failure and subsequent surgical intervention. Another two case reports present the serendipitous discovery and nonsurgical management of accessory canals during the initial treatment of maxillary incisors. CONCLUSIONS AND CLINICAL IMPLICATIONS: It is important for the clinician to be able to detect the signs suggesting the presence of accessory canals in maxillary central incisors. Failure to do so may lead to a less-than-optimal endodontic treatment outcome.

Comparison of apical transportation in four Ni-Ti rotary instrumentation techniques.

A new radiographic technique was used to compare apical transportation in four Ni-Ti rotary instrumentation sequences. Mesiobuccal canals of 60 extracted mandibular molars were randomly divided into four groups. Groups 1 and 3 were instrumented by crown-down and groups 2 and 4 by step-back technique with 0.06 ProFiles series 29 to size 6. In groups 3 and 4 Greater Taper files were first used in a crown-down manner. The central axes of initial and final instruments were radiographically superimposed to measure loss of working length (WL) and transportation at 0, 0.5, 1, 3, and 5 mm from WL. ANOVA test showed no significant differences among groups regarding degree of transportation or loss of WL. Transportation was negatively correlated with radius of curvature at 0.5 and 5 mm from WL. The results indicate that the operational sequence of ProFiles or preinstrumentation with GT files has no effect on degree of transportation and loss of WL.

Analysis of continuous-wave obturation using a single-cone and hybrid technique.

This study analyzed the adaptation of gutta-percha to prepared root canal walls using two obturation techniques and determined the influence of the System-B plugger depth on filling adaptation. Fifty-six extracted human mandibular molars were instrumented using Profile NiTi rotary instruments, stratified based on curvature, then randomly distributed into two groups. Group 1 was obturated using the single-cone continuous-wave technique. Group 2 was obturated with a hybrid technique: lateral condensation followed by a continuous-wave down-pack. Based on System-B plugger penetration, teeth were divided into three subgroups: (a) < 3.5 mm, (b) 3.5 to 4.5 mm, and (c) > 4.5 mm. Roots were horizontally sectioned at 1 mm and 3 mm coronal to the apical foramen, stained, and photographed. Four evaluators scored the adaptation of gutta-percha to the prepared canal walls. In 100% (n = 56) of the samples, no statistically significant difference existed between the two obturation methods at 1-mm (x = 1.80, SD +/- 0.69) or 3-mm (x = 1.804, SD +/- 0.69) sections. Best results were obtained with a plugger depth 3.5 to 4.5 mm from the working length.

Nonsurgical ultrasonic endodontic instruments.

The advent of nonsurgical ultrasonic tips has opened up a new horizon in endodontic treatment. There are a number of nonsurgical endodontic ultrasonic systems currently available in the market and it is difficult to renew all of them. Based on similarities among different instrument systems, and attempt has been made to classify instruments into broad categories. This article describes the utility of each type of ultrasonic tip and the principles behind its usage. These instruments may be area specific or use specific, but can be used in an area other than the one for which they are specifically designed if the general principles regarding ultrasonic tips are understood and applied.

An in vitro comparison of Profile GT and GTX nickel-titanium rotary instruments in apical transportation and length control in mandibular molar.

INTRODUCTION: Profile GT files have been redesigned and are now marketed as GTX nickel-titanium rotary files. METHODS: A double-digital radiographic technique was used to compare apical transportation (AT) and change in working length (CWL) between Profile GT and GTX rotary files. Mesiobuccal canals of 40 extracted mandibular molars were instrumented by either rotary system. The central axes of preoperative (15 K) and master apical rotary file (30/.04) were digitally superimposed. AutoCAD was used to measure AT at 0, 1, and 3 mm from WL. The distance from the file tip to the set WL indicated any CWL. Analysis of variance test showed no significant differences between groups in AT. RESULTS: CWL in GTX (-0.25 +/- 0.42) group was significantly greater than in Profile GT group (0.17 +/- 0.30). CONCLUSIONS: The AT results indicate that the newly designed GTX rotary instruments are as effective as the older Profile GT instruments.

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 patient's 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.

The comparison of gutta-percha and Resilon penetration into lateral canals with different thermoplastic delivery systems.

The aim of this study was to evaluate the ability of Obtura II (Obtura Spartan, Fenton, MO) and Calamus (Densply, Tulsa, OK) to fill artificially created lateral canals in simulated plastic teeth using standard gutta-percha, Flow 150 gutta-percha (Obtura Spartan, Fenton, MO), and Resilon (Resilon Research, LLC, North Branford, CT). Lateral canals were created at 2, 4, 6, 8, 10, and 12 mm from the apex in plastic teeth. The teeth were divided into eight groups. In group 1, teeth were filled with a single increment of Calamus; in group 2, canals were filled with Calamus in three increments. In group 3, Obtura II was used with a single increment of standard gutta-percha, whereas in group 4 Obtura II was used in three increments. Groups 5 and 6 were similarly filled as in the preceding groups. A multiple-comparison analysis of variance test followed by a Tukey post-hoc test were used to compare filling material penetration into the lateral canals and the experimental groups (p < 0.05). The results indicated that the flow of the filling material into lateral canals is a function of the viscoelastic properties of the filling material rather than the mechanical properties of the delivery systems. Our data also suggest that the Resilon filling material flows better into lateral canals when a single backfill technique is used.

Clinical and scanning electron microscopic features of invasive cervical resorption in a maxillary molar.

This case report presents clinical and morphological features of severe invasive cervical resorption (ICR) involving a maxillary first molar. Surface morphology of the ICR defect that extended into enamel was studied using a scanning electron microscope. The topography and morphology of resorbed enamel and pulpal surfaces are described. The pulpal space was characterized by proliferation of fibrovascular tissue invaded by a number of > or = 15-microm-large dentinoclastlike cells. The vertical orientation and hexagonal geometric outlines of enamel rods indicated that the resorptive defect had extended into the outer surface of enamel. Preferential odontoclastic dissolution of interprismatic enamel was noted. Deposits of a cementumlike substance were noticed on enamel surfaces, indicating that resorptive process was coupled with repair. Complete destruction of dentin was associated with no response by the tooth to cold stimulus, supporting the hydrodynamic theory of dentinal sensitivity. The results of this study indicate that in addition to predentin and cementum, the outer surface enamel may be resistant to the resorptive process as well.

A retrospective analysis of factors associated with the periapical status of restored, endodontically treated teeth.

PURPOSE: The purpose of this study was to explore possible associations between prosthodontic, occlusal, endodontic, and periodontal factors and the endodontic status of endodontically treated teeth. MATERIALS AND METHODS: Forty-six patients who had received endodontic treatment followed by a fixed restoration for at least one of their teeth were recalled and examined clinically and radiographically according to a predetermined set of evaluation criteria. A total of 89 teeth were included, and data obtained included assessments of the coronal restoration and post and core, occlusal contact relationships, a number of endodontic parameters, and periodontal status of the study teeth. For the latter assessment, 54 contralateral teeth were available for purposes of comparison. Teeth were grouped into those with and without periapical radiolucencies, and differences between the groups, with respect to all parameters, were analyzed by logistic regression. RESULTS: Three factors were significantly associated with the presence of radiolucency: confirmed occlusal contact, by virtue of the tooth being either involved in group function or the only contact in working-side and protrusive movements, and endodontic filling and crown margins of poor quality. None of the other independent variables showed significant associations with the dependent variable of periapical radiographic appearance. Contralateral teeth had better periodontal conditions than restored study teeth. CONCLUSION: The finding that a good-quality endodontic filling and crown margin improve endodontic outcome corroborates many other similar reports; however, with occlusal contact shown to be associated with failing endodontic treatment, the range of factors that may influence endodontic outcome appears to have widened.