Endodontic Tips Research Articles

Effects of various agitation techniques on sealer penetration in dentinal tubules using CLSM

Aim: To compare the effect of ultrasonic, sonic and rotary sealer activation techniques on depth of penetration of sealer in the dentinal tubules. Materials and Methods: Freshly extracted 60 single rooted human permanent mandibuar premolar with mature apex were collected. A size 10 no. K file (Dentsply Maillefer) was introduced into each canal. The irrigation procedure was accomplished by using 2ml of 5.25% NAOCl for each file used. Roots were randomly divided into 3 groups on the basis of sealer activation techniques. The specimens were kept in incubator at 37 degree Centigrade temperature for 2 days. The dentin segments were examined on a confocal microscope in Jawaharlal Nehru University, New Delhi under 4X,10X magnification. Results: A total of 60 teeth were included in the study and they were divided into three groups on the basis of method of agitation of sealer: GROUP I - Lentulospiral, Group II-Ultrasonic endodontic tip, Group III - Endoactivator and obturation was done with gutta percha. Mean percentage and depth of penetration was greatest in Group II i.e. Ultrasonics when used for agitation and statistically significant than Group I lentulospiral and Group III Endoactivator.

Use of endodontic paper points and Schirmer strips for measurement of tear flow in red-lored parrots (<em>Amazona autumnalis</em>)

Ocular diseases are sub-diagnosed in bird species, partly because of limited diagnostic methods and lack of reference data. Placement of Schirmer tear test strips in the bottom of the conjunctival sac of birds for tear flow measurement can prove to be difficult, whereas paper tips commonly used for dental procedures may be easier to use, due to a more adequate size and shape. Hence, the aim of this study was to assess and compare tear flow values, using ABC Dental® # 30 color paper tips and TearFloTM Test strips in Red-lored Parrots (Amazona autumnalis) (n = 26). Captive birds of undetermined sex were housed in groups under similar environmental conditions and fed the same diet. All animals were deemed healthy through remote and physical examinations. Average tear flow values of 0.6365 ± 0.032 cm/min and 0.5942 ± 0.032 cm/min were obtained with the Schirmer strips test and the endodontic tips respectively. Lack of difference in observed values between measurement techniques (p = 0.3629) indicates that endodontic tips may be a good alternative for tear flow assessment in Red-lored parrots. In addition, endodontic tips are more cost effective and may be less invasive. This study stresses the need to establish species specific ophthalmic reference values for clinical practice in birds, since differences have been reported even in specimens within the same genus.Figure 1. Measurement of tear flow in Red-lored parrots using TearFloTM Test Strips

Root Anatomy of Mandibular Second Premolars in French Subpopulation: A Retrospective Observational Case Series.

Aims:The purpose of this in vivo study is to illustrate endodontic anatomical variants in French subpopulations of human mandibular second premolars to show if the literature matches our findings.Setting and Design:This was an observational retrospective study.Subjects and Methods:This study was performed from September 2016 to September 2017. It was conducted on 56 successive cases of root canal therapies on the mandibular second premolars. All procedures were done in conformity with current state-of-the-art practices in endodontics. These included rigorous clinical and radiographic preaccess analysis, appropriate tooth restoration to insure watertight rubber dam installation, surgical microscopic manipulations for precision, systematic use of ultrasonic endodontic tips to manage cavity access preparation, and step-down technique to shape the root canal systems.Statistical Analysis Used:Fifty-six mandibular second premolars were treated: 76.8% had one canal, and 23.2% had two or more canals.Conclusions:The incidence of two or more canals on mandibular second premolars could be underestimated as our results show. To prevent any missing canals, clinicians must have a perfect knowledge of anatomic variants of the root canal system. Moreover, the systematic use of a surgical microscope, ultrasonic endodontic tips, and a modern step-down technique should facilitate and standardize access cavity preparation, canal localization, and instrumentation.

An In Vivo Study: Location and Instrumentation of the Second Mesiobuccal Canal of the Maxillary Second Molar

The first purpose of this retrospective observational in vivo study was to determine the incidence of the second mesiobuccal canal (MB2) in maxillary second molars. The second purpose was to propose a modern shaping procedure able to transform a difficult canal, like MB2, into a normal canal. This study was led from September 2016 to December 2017, for 15 months. It was conducted on fifty-seven successive cases of root canal therapy on maxillary second molars. All procedures were done in conformity with the current state of the art practices in endodontics. These included rigorous clinical and radiographic pre-access analysis, appropriate tooth restoration to ensure watertight rubber dam installation, surgical microscopic manipulations for precision, the systematic use of ultrasonic endodontic tips to manage the access cavity preparation, and a modern step down technique to shape MB2. Fifty-seven maxillary second molars were treated: 3.5% had one canal, 7.0% two canals, 24.6% three canals; 64.9% four canals (MB2 presence). Weine's method was used to classify mesiobuccal root canal morphology: 27.4% had a type I canal configuration, 35.3% type II, 37.2% type III canal configuration. The perfect knowledge of endodontic anatomy, a painstaking pre-access analysis of the preoperative radiographs, the systematic identification of the CEJ, using a periodontal probe, the use of surgical microscope coupled with the use of specific endodontic ultrasonic tips and the use of a modern step-down technique allows a high accuracy of the access cavity preparation, canal localization and instrumentation. The rate of MB2 localization and instrumentation on maxillary second molars by our surgical protocol is high. The clinician should take the necessary time to locate and negotiate the MB2. The lack of its location can provoke the failure of endodontic treatment.

Comparison of Three Different Sealer Placement Techniques: An In vitro Confocal Laser Microscopic Study.

Introduction:Three-dimensional obturation of the root canal system is the final objective of root canal therapy. Greater penetration of sealer in root dentine lesser will be the voids at the dentine–sealer interface. Hence, analysis of the dentin/sealer interface allows the determination of a filling technique which could obturate the root canals with least gaps and voids. Therefore, the aim of this study is to compare the depth and percentage of sealer penetration into root dentin using three different root canal sealer placement techniques under confocal laser scanning microscope.Materials and Methods:Thirty single-rooted teeth were selected and prepared. Adseal sealer (Meta Biomed, South Korea) was mixed with Rhodamine B dye and applied using lentulo spiral (Dentsply Maillefer, USA) as Group 1, bidirectional spiral (EZ-Fill– EDS, USA) as Group 2, and ultrasonic endodontic tip (Sonofile– Dentsply Tulsa, USA) as Group 3. Canals were then obturated with gutta-percha. The roots were sectioned at the 3 and 6-mm levels from the apical foramen and examined under confocal laser microscope.Results:Maximum mean depth and percentage of sealer penetration were observed for Group 1 and minimum for Group 3. Furthermore, statistical significant differences among Group 1 and Group 3 were found at 6-mm level and among Group 2 and Group 3 were found at 3-mm level (P < 0.05).Conclusion:The depth and percentage of sealer penetration of sealer are influenced by the type of placement technique and by the root canal level, with penetration decreasing apically. Lentulo spiral has shown better penetration of sealer than the bidirectional file and ultrasonics.

Successful removal of a 16 mm long pulp stone using ultrasonic tips from maxillary left first molar and its endodontic management

To present a case report describing successful removal of a 16 mm long pulp stone in a single mass from a maxillary left first molar and its endodontic management. In the presented case, the conventional approach of dissecting the pulp stone was not considered, as radiographically the calcification was extending up to the apex of the palatal root canal and the separation of the coronal and radicular pulp stone would have risked the obliteration of its orifice. A new set of ultrasonic endodontic tips were used for the removal of significantly large pulp stone in single mass.

In vitro investigation of intra-canal dentine–laser beam interaction aspects: II. Evaluation of ablation zone extent and morphology

Laser endodontic tips appear to provide a promising alternative to available treatment modalities in the field of endodontology. With the shortcomings in published results regarding the intra-canal behavioural aspects of those tips, it was the aim of this study to investigate the extent of the intra-canal ablation zone and the pattern associated with those tips. Ninety intact extracted bovine teeth were used to prepare mid-root testing cylinders. The samples were divided into three groups (A, B, C), corresponding to the tip diameters. Each group was further subdivided to be irradiated at three different power settings (1500 mW, 1750 mW, 2000 mW) with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser with a 65% water to 35% air ratio. Collected data were subjected to analysis of variance (ANOVA) and the Tukey test. At a chosen significance level of alpha = 1%, no statistical difference was found among the groups (P > 0.01). The results suggest that shortening of the estimated working length is mandatory for the use of those tips within the canal, and that, provided that certain measurements are used for intra-canal laser ablation, this is a secure mode of treatment. Further investigation and system improvement will be required for more satisfactory results.

In vitro investigation of intra-canal dentine–laser beam interaction aspects: I. Evaluation of ablation capability (ablation rate and efficiency)

The aim of this study was to determine the amount of intra-canal dentine removed with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser using different endodontic tips and different power settings. Ninety intact extracted bovine teeth were selected as samples. After sectioning the roots and preparing the testing cylinders, we divided the samples into three main groups (A, B, C), with further subdivision of each group to be irradiated with three different powers (1500 mW, 1750 mW and 2000 mW). An Er,Cr:YSGG laser system (2.78 microm, 140 micros, 20 Hz and 65% water to 35% air ratio) was used for irradiation, and the loss of intra-canal dentine mass was calculated by the difference between the initial and final sample masses. Data were analysed with Kolmogorov-Smirnov, analysis of variance (ANOVA) and Tukey tests. At a significance level of alpha = 1%, the results showed statistically significant differences (P < 0.0001) between different tip groups, regarding both the ablation rate and the ablation efficiency criteria. With regard to the three irradiation power settings, statistically significant difference were recorded only between groups C and A, for the ablation rate criteria. The intra-canal ablation ability of the Er,Cr:YSGG laser improved with increasing power and/or tip diameter. The latter exhibited a stronger influence on ablation rate and efficiency. Laser intra-canal ablation is an important addition to the field of endodontics; nevertheless, further investigations and system improvements are required.

In vitro evaluation of the temperature increment at the external root surface after Er,Cr:YSGG laser irradiation of the root canal

A study was made to determine the temperature increment at the dental root surface following Er,Cr:YSGG laser irradiation of the root canal. Human canines and incisors previously instrumented to K file number ISO 30 were used. Irradiation was carried out with glass fiber endodontic tips measuring 200 mm in diameter and especially designed for insertion in the root canal. The teeth were irradiated at 1 and 2 W for 30 seconds, without water spraying or air, and applying a continuous circular movement (approximately 2 mm/sec.) in the apico-coronal direction. At the 1 W power setting, the mean temperature increment was 3.84 degrees C versus 5.01 degrees C at 2 W. In all cases the difference in mean value obtained after irradiation versus the mean baseline temperature proved statistically significant (p<0.05). Application of the Er,Cr:YSGG laser gives rise to a statistically significant temperature increment at the external root surface, though this increment is probably clinically irrelevant, since it would appear to damage the tissues (periodontal ligament and alveolar bone) in proximity to the treated tooth.

In vitro preliminary study to evaluate the capability of Er,Cr:YSGG laser in posterior teeth root-canal preparation with step-back technique

This preliminary study was to investigate in vitro the Er,Cr:YSGG laser ablation capability, both range (enlargement aspects of laser tips corresponded to conventional endodontic files) and quality (removing of smear layer and opening of dentinal tubules) to clean and shape the root canal for final obturation step. The crowns of 15 extracted multi-rooted posterior human teeth were resected, and then 15 canals were prepared by an Er,Cr:YSGG laser up to 1.5 W (actual power output) using the step-back technique, while the other 15 canals (control) were enlarged conventionally by K-flex file. The results revealed that posterior root-canal preparation could be achieved by laser beam transmitted to the canal using endodontic tips. At a chosen significance level of alpha = 1%, the results showed no significant statistical difference between the two groups (P > 0.01). Considering the results of this current study, laser-based root-canal preparation still shows certain limitations, and further improvements are mandatory for higher achievement and better preparation outcomes.