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At least 1,225 records · Page 68Linked to original sources
PubMed2002

Hemostatic efficacy and cardiovascular effects of agents used during endodontic surgery.

The hemostatic efficacy, as well as the cardiovascular effects, of two hemostatic agents currently used during endodontic surgery was examined. The hemostatic agents used were epinephrine pellets (Racellet pellets) or 20% ferric sulfate (Viscostat). Patients were assigned to one of two experimental groups. Blood pressure and pulse rate were recorded pre- and postoperatively and at three additional times during the surgery (root-end resection, root-end preparation, and filling). The adequacy of hemostasis was rated by the surgical operator. Results indicated that there is no significant change in cardiovascular effects when using either of these hemostatic agents. Except in one case where ferric sulfate was the agent, both agents produced surgical hemostasis that allowed for a dry field for root-end filling.

Administration, Topical↗
PubMed2002

Effect of electronic apex locators on cardiac pacemaker function.

The purpose of this study was to assess the effects of five electronic apex locators on pacemaker function in vitro. A Biotronik Actros DR+ pacemaker was evaluated at maximum sensitivity on a flat bench top. The pacemaker lead, electronic apex locator, and oscilloscope were connected across a 150-ohm resistor. Pace monitoring was carried out with a Biotronik EPR 1000 programmer and a Tektronix TDS 220 2-channel digital real-time oscilloscope. Four of five electronic apex locators tested did not cause inhibition or interfere with normal pacemaker function. It seems that electronic apex locators can be used safely in patients with pacemakers.

Dental Instruments↗
PubMed2004

Use of self-etching adhesives to seal resected apices.

The purpose of this study was to evaluate the sealing ability of four self-etching adhesives placed over blood-contaminated/uncontaminated resected root apices without root-end preparation. Extracted maxillary incisors and canines were randomly divided into four groups of 10 teeth each. After canal preparation and resection of the apex, four self-etching adhesives (Clearfil SE Bond, One-Up Bond F, Unifil Bond, and ABF) were applied over the control and contaminated surfaces. The roots were then subjected to 15 cm of water pressure to simulate periapical microleakage stress. Data were analyzed using a two-way repeated measures, ANOVA. Positive and negative controls responded as expected. Statistical analysis indicated that there were no significant differences in the sealing effectiveness among the adhesives applied to contaminated or uncontaminated groups. All contaminated groups had significantly higher leakage (p < 0.003) than their uncontaminated pairs.

Analysis of Variance↗
PubMed2004

Effects of multiple dentinal lesions on the rat pulp.

The purpose of this study was to compare the effects of single and multiple dentinal lesions on the dental pulps of rats. 3H-proline was used to measure pulpal reactionary dentin deposition, and 3H-thymidine was used to measure pulpal cell proliferation by radioautography. Data were compared by factorial analysis of variance and a post-hoc Tukey test. A significant increase in radiolabeled collagenous proteins within reactionary dentin and pulpal cell labeling indices were evident coincident to single dentinal injuries, compared with controls (p < 0.001). After double injuries, the radiolabeled collagenous proteins within reactionary dentin and the pulpal labeling indices remained significantly greater than in controls (p < 0.01); however, each was significantly less than after single injuries (p < 0.05). These data suggest that pulpal cell proliferation and collagenous protein deposition into reactionary dentin are decreased subsequent to a previous dentinal injury. Thus, the healing potential of the dental pulp could be decreased by recent tooth cavity preparation.

Analysis of Variance↗
PubMed2005

The effect of mesio-distal chamber dimension on access preparation in mandibular incisors.

Because the pulp chamber of a young mandibular incisor flares coronally in a mesio-distal dimension, the access form pictured by a number of authors is triangular in shape. As a person ages, the chamber recedes and the access shape becomes oval in form consistent with a canal system that is primarily bucco-lingual in orientation. Endodontic literature generally recommends either the triangular or oval access shape without acknowledging that both are appropriate at a given time in the life of the individual. The question addressed by this study is when does the pulp chamber loose its coronal flare to become primarily oval in shape, and as a consequence of this change, when should the access form go from triangular to oval. It was concluded that by the age of 40 the canal has decreased in size sufficiently to justify in routine cases an oval preparation of less than 2 mm mesio-distal width.

Adult↗
PubMed2005

Root canal treatment in a mandibular second premolar with three root canals.

According to the endodontic literature, the possibility of three canals in mandibular second premolars is quite small. When three or more canals are present separation of the root canals has only been described at mid-root level. The present case describes root canal treatment of a root canal aberration at the level of the apical third (apical root canal separation starting at a length of 20 mm) where a combined use of the fiberoptic endoscope and the operating microscope was necessary to locate the canal orifices and to enter these orifices. The present report emphasizes the need of color contrast to enhance visualization.

Adult↗
PubMed2005

Effect of root canal size and external root surface morphology on fracture susceptibility and pattern: a finite element analysis.

The aim of the study was to determine the extent to which canal size, radius of curvature and proximal root concavity influence fracture susceptibility and pattern. A standardized cross-section of the mid-root region of a mandibular incisor was created by averaging the dimensions of 10 extracted teeth, and then the basic finite element analysis (FEA) model was created. By varying canal diameter, shape, and proximal concavity, these factors could be examined for roles in fracture susceptibility and pattern. The factors all interact in influencing fracture susceptibility and pattern, with dentin thickness not the only determining factor. The removal of dentin does not always result in an increased fracture susceptibility.

Dental Pulp Cavity↗
PubMed2005

The role of apical instrumentation in root canal treatment: a review of the literature.

The issue of final apical preparation size remains controversial despite considerable clinical and in vitro research. The astute clinician must be aware of this research before choosing any instrumentation system because the informed clinician's decision must be guided by the best available evidenced-based information. This review article generated a Medline-based search strategy to disclose these studies and provides a critique and summary of the results.

Dental Instruments↗
PubMed2005

A comparative study of three different root canal curvature measurement techniques and measuring the canal access angle in curved canals.

In the first part of this study the Schneider (S), Weine (W), and Long-Axis (LA) techniques are used for comparing the measurement of canal curvature. One hundred mandibular first and second molar teeth were selected. Radiographs were taken after inserting size 10 K-files into the mesiobuccal root canals. The radiographic findings were digitized on a computer, and the three different curvature angles were measured from drawings of the same root canal and compared statistically. ANOVA showed that there were significant differences between the curvature angle values determined using each technique (p < 0.001). In the second part of this study the term "canal access angle" (CAA) was introduced and it was defined by examining the morphology of canal curvature. Canal length, curvature distance (y), curvature height (x), Schneider angle, and the newly defined CAA were evaluated statistically. Using a multiple regression analysis, the CAA was significantly related to x (p < 0.001) and y (p < 0.005). There was a positive correlation (r = 0.74) between the CAA and curvature height (x). The results indicated that the CAA is a more effective way of evaluating the root canal curvature.

Dental Pulp Cavity↗
PubMed2004

The accuracy of electronic working length determination.

AIM: To determine in vivo the accuracy of two impedance quotient apex locators under clinical conditions. METHODOLOGY: Electronic working length determination was carried out before extraction in 79 human teeth with 93 root canals. In 51 root canals, the determination was performed using the apex locator Justy II(R) (Hager & Werken, Duisburg, Germany); in 42 canals, the apex locator Endy 5000(R) (Loser, Leverkusen, Germany) was used. A root canal instrument was fixed at working length with composite material prior to extraction followed by the exposure of a radiograph. After histological preparation of the apical region, the teeth were examined under a light microscope. The distance of the file tips to the target intervals 'minor foramen - major foramen' and 'apical canal constriction' was determined. These values were compared with the calculated working lengths, determined by radiographic assessment. The data were statistically analysed by a paired t-test. RESULTS: For both apex locators and both target intervals, no significant differences between the electronic and radiographical assessments were recorded. The probability of determining the area between minor and major foramen was 82.4% for Justy II and 81% for Endy 5000. However, accurate determination of the apical constriction was only successful in 51% (Justy II) and 64.3% (Endy 5000) of canals. Variation of the inaccurate measurements was higher for Endy 5000 than for Justy II. CONCLUSIONS: Under clinical conditions, it is possible to determine the region between the minor and major apical foramen with electronic length measuring devices (ELD). However, use of these devices does not result in precise determination of the apical constriction.

Adult↗
PubMed2004

Accuracy of the Justy II Apex locator in determining working length in simulated horizontal and vertical fractures.

AIM: To study the effectiveness of an electronic apex locator (EAL; Justy II; Yoshida Dentcraft, Tokyo, Japan) in locating simulated horizontal and vertical fractures in single roots. METHODOLOGY: An EAL was used to measure the distance within the canal of horizontal (n = 31) and vertical (n = 31) fractures, created with a disk in single-rooted teeth. Accuracy of the EAL was evaluated by comparing the measurements with those made using a size 10 file. Data were analysed with the non-parametric Passing and Bablok method. RESULTS: For simulated horizontal fractures, the EAL measured exactly the same length as a size 10 file, without constant or proportional errors. In vertical simulated fractures, the EAL measured (on average) with a constant error of 7.5 mm shorter than the size 10 file; the difference had a wide confidence interval (-72.3 to 2.6 mm). CONCLUSIONS: In this laboratory study, the Justy II EAL was able to determine accurately the position of simulated horizontal fractures, but was unreliable when measuring simulated vertical fractures.

Dental Instruments↗
PubMed1996

Assessing apical deformation and transportation following the use of LightSpeed root-canal instruments.

The LightSpeed root canal instrument is similar in design to the Canal Master instrument with the exception of being engine driven and fabricated from nickel-titanium alloy. The purpose of the design of these instruments is to reduce apical transportation of the canal during cleansing and shaping procedures. Twenty extracted human molar teeth with roots of varying degrees of curvature were used in this study. A double exposure radiographic technique was used to assess the presence or absence of apical transportation resulting between the initial instrument and the final instrument, a size 50 LightSpeed. Only one of the 20 teeth examined exhibited apical transportation. Results of this study suggest that little or no apical canal transportation could be expected when curved canals are instrumented using the LightSpeed root canal instruments.

Dental Instruments↗
PubMed2003

Diagnosis and root canal treatment of a mandibular second premolar with three root canals.

AIM: To present a case of a mandibular second premolar with three root canals. SUMMARY: An accurate diagnosis of the morphology of the root canal system is a prerequisite for successful root canal treatment. A review of the literature reveals a low incidence of all types of premolars with three root canals. Diagnostic means such as preoperative radiographs and examination of the pulp chamber floor aid the location of root canal orifices. The diagnostic and therapeutic problems concerning premolars with unusual anatomy are described on the basis of a clinical example. A case report describes the successful treatment of a mandibular second premolar with three root canals. KEY LEARNING POINTS: Clinicians should be aware of unusual root canal anatomy in mandibular premolars. Radiographs exposed at two different horizontal angles and their careful interpretation facilitate the search of additional root canals. The use of magnification and additional lighting are recommended for the clinical examination of the pulpal floor.

Adult↗
PubMed2004

Electronic apex locators.

Prior to root canal treatment at least one undistorted radiograph is required to assess canal morphology. The apical extent of instrumentation and the final root filling have a role in treatment success, and are primarily determined radiographically. Electronic apex locators reduce the number of radiographs required and assist where radiographic methods create difficulty. They may also indicate cases where the apical foramen is some distance from the radiographic apex. Other roles include the detection of root canal perforation. A review of the literature focussed first on the subject of electronic apex location. A second review used the names of apex location devices. From the combined searches, 113 pertinent articles in English were found. This paper reviews the development, action, use and types of electronic apex locators.

Dental Instruments↗
PubMed2005

A comparison between two electronic apex locators: an in vivo investigation.

AIM: To compare in vivo the Apex Finder and Root ZX electronic apex locators (EALs) at five different stages during root canal instrumentation. METHODOLOGY: The Apex Finder and Root ZX were used in 64 teeth with either vital or necrotic pulps. Informed consent was obtained by each patient under a study protocol approved by an ethical committee from the University of Trieste. Measurements were made: (stage 1) before instrumentation and irrigation; (stage 2) after brief filing, irrigation with 70% isopropyl alcohol and partial drying; (stage 3) after canal lubrication with EDTA gel (RC-Prep); (stage 4) after complete instrumentation and irrigation with NaOCl 5%; (stage 5) after drying of the final instrumented canal. Stages 2, 3 and 5 were considered low canal conductivity conditions and stage 4 as high. Teeth were then extracted and a size 15 K-file was inserted until its tip was observed under stereomicroscope to reach the foramen and the corresponding length was recorded to an accuracy of 0.25 mm and compared with values derived from the EALs. RESULTS: The data revealed 133 unstable measurements (out of 640): some (68) related to low canal conductivity conditions (more frequently for Root ZX, 67; P < 0.05), and others (63) related to NaOCl presence in the canal (more frequently for Apex Finder, 58; P < 0.05). Accuracy was calculated only on stable measurements. The Root ZX showed significantly (P < 0.05) more precise measurements overall (-0.03 +/- 0.39 mm) compared with the Apex Finder (-0.31 +/- 0.46 mm). Under dry canal conditions the Apex Finder provided the greatest accuracy (-0.0 +/- 0.21) compared with the Root ZX (-0.05 +/- 0.32) (significance P < 0.05). CONCLUSIONS: Under the five different clinical situations both EALs revealed accurate measurements. Apex Finder was negatively influenced by NaOCl in the root canal. The Root ZX was more frequently unable to reveal stable measurements in low conductivity canals.

Analysis of Variance↗
PubMed2005

Determining the apical terminus of root-end resected teeth using three modern apex locators: a comparative ex vivo study.

AIM: To assess ex vivo the accuracy of various electronic apex locators in locating the apical terminus of root-end resected teeth. METHODOLOGY: Ninety extracted human posterior teeth (182 root canals) were prepared to a minimum size of 40 and filled with gutta-percha and sealer. After resection of the apical 3 mm of the root, the root canal filling was removed using HERO rotary instruments. The size of the root canal at the apical terminus after removal of the filling ranged from size 50 to 90. The root canal length to the apical terminus was determined using 3 apex locators (Root ZX, Raypex4 and Apex Pointer). A new mounting model that utilized a micrometer was used to perform the measurements and to visually determine the actual position of the apical terminus. The frequency of locating the apical terminus and the corresponding 95% confidence interval (CI) were calculated. Additionally, the coefficient of repeatability of each apex locator and the limits of inter-operator agreement were determined. RESULTS: All apex locators showed an acceptable repeatability (0.02-0.03 mm coefficient of repeatability) and narrow limits of inter-operator agreement (+0.07 and -0.07 mm). The accuracy of determining the apical terminus within 1 mm in the root canal was as follows: Root ZX 90% (164/182 root-canals) [95%CI: 86-94%], Raypex4 74% (135/182 root-canals) [95%CI: 68-80%], and Apex Pointer 71% (129/182 root canals) [95%CI: 65-77%]. No over-instrumentation resulted when the Root ZX device was used. In contrast, using the Raypex4 or the Apex Pointer device resulted in over-instrumentation in 8 of 182 root canals (4%). CONCLUSIONS: Under the conditions of this study all three apex locators were able to detect the apical terminus of root-end resected teeth with an acceptable range. The Root ZX device was the most accurate without over-instrumentation of the root canals.

Dental Pulp Cavity↗