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At least 757 records · Page 42Linked to original sources
PubMed1998

Histological evaluation of the response of apical tissues to glass ionomer and zinc oxide-eugenol based sealers in dog teeth after root canal treatment.

The object of the study was to compare two commercial root canal sealers: Ketac-Endo (a glass ionomer cement) and Fill Canal (a zinc oxide-eugenol cement). A total of 34 root canals from dog premolars with vital pulps were used. After instrumentation, the root canals were sealed with Ketac-Endo and Fill Canal cements using gutta-percha and a lateral condensation technique. After 270 days the animals were sacrificed with an anesthetic overdose and the maxillae and mandibles were removed and fixed in formalin for 48 h. After routine histological processing the sections were stained with hematoxylin-eosin and Mallory trichrome stains. Microscopic analysis revealed that Ketac-Endo cement presented better results than Fill Canal cement.

Animals↗
PubMed1998

An in vitro comparison of thermoplasticised gutta-percha obturation techniques with cold lateral condensation.

This study compared the apical sealing ability, obturation time and extrusion of gutta-percha and sealer when root canals were obturated using either cold lateral condensation or one of the three methods using thermoplasticised gutta-percha (Alpha Seal, Thermafil or JS Quick Fill) in vitro. One hundred and thirty-one root canals from 78 extracted human teeth were used; 116 canals were divided into five groups so that they were balanced with respect to prepared canal anatomy, and the remaining 15 canals were used as positive and negative controls. The canals in the first four groups were prepared with hand files using the step-down technique to a standard apical size and flare. The last group was prepared using engine-driven rotary nickel-titanium files (McSpadden) to a similar apical size and flare. One of the four obturating techniques was used to fill the canals in each of the first four groups. The fifth group was obturated using the Alpha Seal technique. The roots were immersed in india ink, demineralised and rendered transparent to assess the extent of maximum lincar dye penetration. The Alpha Seal groups had the highest number of specimens without any leakage. There was a significant difference in the proportions of specimens that did not leak when the Alpha Seal (P < 0.01) and cold lateral condensation groups (P < 0.05) were compared with JS Quick Fill. Cold lateral condensation had a higher proportion of specimens with leakage in canals with curvature greater than 20 degrees than in canals with curvatures less than 20 degrees (P < 0.05). The curvature of canals had no effect on the sealing ability of the other techniques. The method of canal preparation had no effect on the sealing ability of Alpha Seal. Alpha Seal, Thermafil and JS Quick Fill were significantly quicker to perform than cold lateral condensation.

Analysis of Variance↗
PubMed1999

Dye leakage and SEM study of roots obturated with Thermafill and dentin bonding agent.

The apical seal of roots obturated with a dentin bonding agent and Thermafill with and without the use of sodium hypochlorite as an irrigating solution was compared by a dye leakage test. Roots obturated with Thermafill and a zinc oxide eugenol sealer were used as controls. Thirty-eight roots were prepared chemomechanically and divided into three experimental groups. The teeth of group 1 were filled with Thermafill and the dentin bonding agent using sodium hypochlorite as the irrigant. The teeth of group 2 were filled in the same way, but saline solution was used as the irrigant. Before the root canal was filled the smear layer was removed from the root canal walls of both groups by rinsing the root canal with a 17% EDTA solution. The teeth of group 3 were filled with Thermafill and a zinc oxide eugenol sealer. The teeth were immersed in 2% methylene blue solution. The root fillings of groups 1 and 2 leaked significantly more than those of group 3. The resin-dentin-guttapercha interface of group 1 was observed by scanning electron microscopy and showed a typical hybrid layer. An intimate contact between resin and dentin was present in group 2, but a resin-dentin interdiffusion zone was only occasionally observed. The use of dental adhesives and the hybrid layer formation did not improve the seal of Thermafill root canal fillings.

Coloring Agents↗
PubMed1999

Apical microleakage after lateral condensation, hybrid gutta-percha condensation and Soft-Core obturation: an in vitro evaluation.

The purpose of the present study was to evaluate the apical seal of root canals filled with a cold lateral condensation, a hybrid gutta-percha condensation technique and with Soft-Core obturators. Three groups of 35 maxillary anterior teeth and four control anterior teeth were treated with a crown-down/step-back technique. All roots were submerged in India ink for 1 week. The roots were cleared and the degree of linear dye penetration was measured. The mean apical leakage for the Soft-Core technique was at least twice as extensive as for the two other gutta-percha obturation techniques. No statistically significant differences were found between the two other condensation techniques.

Dental Leakage↗
PubMed2004

Infected immature teeth treated with surgical endodontic treatment and root-reinforcing technique with glass ionomer cement.

The authors propose surgical endodontic treatment of immature teeth characterized by necrosis and infection, especially after failure of apexification or in the presence of older, fibrous, and extensive lesion. A glass ionomer cement, autopolymerizable and condensable, is used as retro-filling material and as a reinforcement material for the canal walls. The variety of different cases presented here show that this rapid technique is reliable and reproducible.

Adult↗
PubMed2001

Apical sealing ability of five endodontic sealers.

Because apical leakage may be a cause of failure of endodontic treatment, the purpose of this study was to compare the apical seal provided by five endodontic sealers. After cleaning and shaping procedures, the root canals of 75 human cuspids were obturated by lateral condensation using gutta-percha and the following sealers: Kerr Pulp Canal Sealer EWT, Grossman's sealer, ThermaSeal, Sealer 26, and AH Plus. These root-filled teeth were then maintained at 37 degrees C and 100% humidity for two days. After immersion in a solution containing black India ink and fetal bovine serum for five days, the teeth were demineralised and rendered transparent. The extent of dye penetration was examined under a stereomicroscope. The results showed that Grossman's sealer exhibited significantly more leakage than the other sealers, except ThermaSeal. There was no significant difference between ThermaSeal and AH Plus. No significant differences were observed for Kerr Pulp Canal Sealer EWT when compared with either ThermaSeal or AH Plus. There was significantly less leakage for Sealer 26 when compared with the other sealers tested, except AH Plus.

Bismuth↗
PubMed2004

Frequency of transverse anastomoses with and without apical communication in Japanese population teeth.

The aim of this study was to describe and measure the frequency of transverse anastomoses with and without an apical communication in Japanese population teeth. One hundred and twenty-three extracted teeth from Japanese people were used in this study. The sample consisted of: 63 mandibular first molars, 30 maxillary first molars and 30 maxillary first premolars. Access openings were made through the crowns to the pulp chamber and India ink was injected into the coronal pulp space and vacuumed from the apical end. The teeth were cleaned and digital micrographs taken from several angles to identify transverse anastomoses. Fourteen teeth had only one canal and 81 teeth out of 109 (74%) had transverse anastomoses including 6 teeth (5.5%) that had an apical communication. Most of the anastomoses (50) were located in the middle portion of the canal and 22 (20%) teeth showed multiple anastomoses. Special attention must be taken after resection of roots with apparent multiple canals. The potentially exposed exits and/or isthmuses should be taken into consideration during surgical endodontic treatment.

Asian People↗
PubMed2005

Apically-extruded debris using the ProTaper system.

The purpose of this in vitro study was to determine the quantity of debris and irrigant extruded apically using the ProTaper system compared to ProFiles and K-Flexofiles. Thirty-six mesio-buccal root canals of human mandibular molars were selected and divided into three groups of twelve canals. Two groups were instrumented with ProFiles and ProTapers according to the manufacturer's instructions. The other group was instrumented with K-Flexofiles using the step-back technique. A standard amount of irrigant was used for each canal. Apically-extruded debris and irrigant was collected in pre-weighed vials. The mean weight of extruded debris and irrigant for each group was statistically analysed using Student's t-test and one-way ANOVA. All instrumentation techniques produced extruded debris and irrigant. Although the mean amount of extrusion with the step-back technique was higher than the two rotary systems, there was no significant difference between the three groups (p > 0.05). NiTi rotary systems were associated with less apical extrusion, but were not significantly better than hand file instrumentation. All techniques extruded debris.

Analysis of Variance↗
PubMed2006

Determination of root canal curvatures before and after canal preparation (part II): A method based on numeric calculus.

The aim of this paper is to present a new method based on numeric calculus to provide data on any type of root canal curvature at any point of the long axis of the canal. Twenty severely curved, simulated root canals were prepared with rotary FlexMaster and Profile instruments in the crown-down technique and manually in the step-back technique. The inner and outer curvatures were registered in a system of coordinates before and after preparation in increments of 0.5 mm. Using an equalising function, the curvatures were first represented in graphic and algebraic form. The maximum and the mean curvature as well as the length of the arc from the apical foramen to the point of maximum curvature were determined mathematically. An increase in maximum curvature was registered for all four shaping systems investigated. The radius of the inner curvature decreased by 0.5-1.2 mm in the manual systems as a result of the preparation. The Profile system displayed the smallest changes in radius (-0.9 mm) even with the outer curvature, and manual preparation with stainless steel files the most pronounced change (-1.8 mm). The point of maximum curvature at the inner curvature was displaced by 1.6 mm to the apical foramen through manual preparation with Ni-Ti files. At the outer curvature, the maximum displacement (1.8 mm) recorded was also the result of preparation with Ni-Ti hand files, while a displacement of only 0.3 mm to the apical foramen was recorded with the other systems. The method offers a means of determining curvatures precisely without random specification of reference points. The method is also capable of registering only minor changes in curvature in the two-dimensional long axis of the canal.

Calibration↗
PubMed2006

Effect of Waterlase laser retrograde root-end cavity preparation on the integrity of root apices of extracted teeth as demonstrated by light microscopy.

Most endodontists use ultrasonic instruments for retrograde root-end cavity preparations even though they have been found to produce cracks. In this laboratory study, thirty-six randomly chosen roots had root-end cavity preparations made with the Waterlase laser and only one questionable intra-canal crack was found. It was concluded that the Waterlase laser when used to make endodontic root-end cavity preparations produces either no cracks, or a very low percentage (2.8%) of cracks.

Apicoectomy↗
PubMed2002

Factors influencing the long-term results of endodontic treatment: a review of the literature.

The purpose of this review of the literature is to examine the factors and their influence on the outcome of endodontic treatments, and also to attempt to have an authors' consensus concerning the impact of these factors on long-term results. The documentary research was conducted using the meta-analysis principles of critical reading of the literature. Two groups of factors can be identified regarding the outcome of endodontic treatments: those which influence the success of the procedure and those which do not significantly affect the success rate. Agreement is obtained in all studies on two major factors, the preoperative periapical status and the apical limit of the obturation, which appear to strongly influence the success of endodontic therapy. This review highlights the methodological problems of retrospective studies and points out the need for consensus regarding the evaluation criteria of root canal therapy.

Dental Pulp↗
PubMed2005

21st century endodontics: part 3.

Root canal treatment is often regarded as a simple technical exercise that results in a nice white line on the final radiograph. In fact nothing could be further from the truth, as may be seen from the case illustrated in Figure 1. It is hoped that the first two papers in this series have established that the rationale for modern root canal treatment is the removal of infection from the entire root canal system. This, of course, presumes correct diagnosis and treatment planning, and an essential knowledge of canal morphology. Endodontic preparation is a chemo-mechanical process and both the chemical and the mechanical components play an equal part. The term 'cleaning and shaping' may be associated with canal preparation from previous endodontic teaching. In the 21st century this has been subtly but essentially changed to 'shaping and cleaning'. Instruments are used to rapidly shape the canal to permit the ingress of chemical agents to the entire root canal system.

Dental Pulp Cavity↗
PubMed1999

Timing of apical closure of the maxillary canine and mandibular first molar teeth of cats.

Stage of apical closure was determined by radiographing the jaws of 15 cats at intervals from 5-11 months of age. The apices of the left mandibular first molar tooth were closed in all 15 cats by seven months of age and the apices of the left maxillary canine teeth were all closed by 11 months of age. The implications of the age of closure on endodontic pathology and treatment are discussed.

Animals↗