Fracture resistance of lab composite versus all-ceramic restorations in class II inlay cavity preparations: An in vitro study.

Aim: The aim of this study was to evaluate and compare the fracture resistance of inlay preparations restored with indirect lab composite, conventional and translucent monolithic zirconia-based ceramics. Materials and Methods: Fifty freshly extracted human maxillary premolars were selected for the study. Standardized inlay cavities were prepared and restored with indirect lab composite, conventional monolithic zirconia-based ceramic and translucent monolithic zirconia-based ceramic. After restoration each sample was subjected to axial compressive load with Universal testing machine. The force required to induce fracture was recorded in Newton (N). Statistical Analysis Used: The data were analyzed using the one-way ANOVA test and Post hoc Bonferroni multiple comparison test. Results: Results revealed that fracture resistance of prepared inlay cavities restored with conventional monolithic zirconia-based ceramics was found to be best followed by other groups. Group I > Group IV > Group V > Group III > Group II. Conclusion: The fracture resistance of conventional monolithic zirconia-based ceramic inlays and translucent monolithic zirconia-based ceramic inlays were comparable with intact teeth but, indirect lab composite inlays showed lower fracture resistance than all.

Evaluation of the efficacy of nitrous oxide inhalation sedation on anxiety and pain levels of patients undergoing endodontic treatment in a vital tooth: A prospective randomized controlled trial.

CONTEXT: Anxiety and fear of pain are the two major deterrents for which patients avoid dental treatment. Local anesthetic, which forms the foundation for the delivery of pain-free endodontic treatment, does not serve the purpose in anxious patients and requires augmentation with other pharmacological agents. AIMS: The aim of this study is to observe the effectiveness of nitrous oxide in alleviating patient anxiety and pain during endodontic treatment of a vital tooth. SETTINGS AND DESIGN: The present in vivo study was conducted on sixty healthy patients from the Outpatient Department of Genesis Institute of Dental Sciences and Research, Ferozepur, Punjab, India. SUBJECTS AND METHODS: Sixty anxious patients having irreversible pulpitis in their lower molar were selected and divided into two groups, namely control group and intervention group, with thirty patients placed in each group. In control group, access opening and pulp extirpation was done under local anesthesia only, whereas in intervention group, access opening and pulp extirpation was done under local anesthesia and nitrous oxide sedation. The anxiety levels of patients, before and after the treatment, were measured using the Modified Dental Anxiety Scale. Pain felt by the patients during administration of local anesthesia and during access opening was measured using the Visual Analog Scale. STATISTICAL ANALYSIS USED: The data were analyzed using ANOVA and paired t-test, and graphical analysis of the data was done. RESULTS: Significant reduction in anxiety and pain levels of patients during endodontic access opening including significant reduction in pain during administration of local anesthesia was observed under nitrous oxide sedation. CONCLUSIONS: Conscious sedation with nitrous oxide is a useful technique to add to the armamentarium used in the treatment of teeth with symptomatic irreversible pulpitis.

Comparative evaluation of push-out bond strength of root-end filling materials in root-end cavities prepared by laser or ultrasonic technique: An in vitro study.

CONTEXT: The use of mineral trioxide aggregate (MTA) and Biodentine as a root-end filling materials used in the root-end cavities prepared by laser or ultrasonic technique is a current topic in the branch of dentistry and push-out bond strength is used to measure the adhesiveness provided by the root-end filling materials. AIM: The aim of this study is to evaluate the push-out bond strength of MTA and Biodentine in root-end cavities prepared by erbium:yttrium-aluminium-garne (Er:YAG) laser and ultrasonic retrotip. MATERIALS AND METHODS: A total of 40 extracted maxillary central incisors and canines were selected. Chemomechanical preparation and obturation were done. Root-end resections were performed followed by the root-end cavity preparation and root-end filling. Specimens were divided into four groups. Root-end cavities prepared by Er:YAG laser and filled with MTA, root-end cavities prepared by Er:YAG laser and filled with Biodentine, root-end cavities prepared by ultrasonic retrotip and filled with MTA and root-end cavities prepared by ultrasonic retrotip and filled with Biodentine, respectively. The apical end was again sectioned perpendicular to the long axis. The push-out bond strength was evaluated using a universal testing machine. STATISTICAL ANALYSIS USED: The data were analyzed using the analysis of variance and post hoc Tukey test. RESULTS: Difference between push-out bond strength of root-end filling materials to root-end cavity walls prepared by laser and ultrasonic retrotips was statistically nonsignificant. Push-out bond strength of MTA and Biodentine did not differ significantly. CONCLUSION: Difference between push-out bond strength of MTA and Biodentine to root-end cavity walls prepared by Er:YAG Laser or ultrasonic retrotip were statistically nonsignificant.

Assessment of consistency in the dimension of gutta-percha cones of ProTaper Next and WaveOne with their corresponding number files.

OBJECTIVES: To compare the dimensions of gutta-percha (GP) cones of ProTaper Next (25/0.06) and WaveOne (25/0.08) in relation to their corresponding instruments of the same dimension, respectively. MATERIALS AND METHODS: Two groups of GP cones were made with 25 cones in each group. Group 1 consisted of 25 GP cones # 25/0.06 (ProTaper Next). Group 2 consisted of 25 GP cones # 25/0.08 (WaveOne). Measurements were done at D1 (1 mm short of the tip), D3 (3 mm short of the tip), and D11 (11 mm short of the tip) for GP cones of both groups and were compared with their corresponding instruments. RESULTS: Group 1 (ProTaper) 25/.06 GP points showed greater diameters than those of the corresponding instrument, which was statistically significant. Group 2 (WaveOne) 25/0.08 GP points showed greater diameters than those of the corresponding instrument which was statistically significant whereas it was nonsignificant at level D1. CONCLUSION: Diameters of both ProTaper Next and WaveOne GP cones were greater than their corresponding instruments. Hence, there are chances of under obturation with both systems.

Comparison of incidence of dentinal defects after root canal preparation with continuous rotation and reciprocating instrumentation.

Biomechanical preparation is one of the most important steps in endodontic therapy. Rotary instrumentation has facilitated this step. Nowadays the market is flooded with different types of rotary instruments. The present study compared the root dentinal crack formation with continuous rotating versus reciprocating root canal preparation methods. One hundred and fifty freshly extracted teeth were used for the study. They were divided into 5 groups with 30 teeth in each group. Thirty teeth were kept under control group A and no root canal preparation was done for this group. Another 30 teeth were prepared with hand files which were kept under control group B. In the experimental groups (sample size, n=30 each) root canals were prepared with ProTaper, K3XF rotary system and WaveOne. Sectioning of these teeth was done at 3, 6 and 9mm from the apex and were evaluated for the presence of any defects. Root dentinal cracks were produced with each type of rotary instruments. Statistical analysis showed no significant difference in root dentinal crack formation between control groups and WaveOne system. There was statistically significant difference in root dentinal crack formation when the canals were prepared with ProTaper and K3XF rotary system. So it was concluded, that continuous rotating instruments could produce dentinal crack formation. Root canal instruments with reciprocating movement appear to be a better option than continuous rotation movement.

Comparison of dentinal damage induced by different nickel-titanium rotary instruments during canal preparation: An in vitro study.

AIM: To compare dentinal damage caused by hand and rotary nickel-titanium instruments using ProTaper, K3 Endo, and Easy RaCe systems after root canal preparation. MATERIALS AND METHODS: One hundred and fifty freshly extracted mandibular premolars were randomly divided into five experimental groups of 30 teeth each and biomechanical preparation was done: Group 1 with unprepared teeth; Group 2 were prepared with hand files; Group 3 with ProTaper rotary instruments; Group 4 with K3 rotary; Group 5 with Easy RaCe rotary instruments. Then, roots were cut horizontally at 3, 6, and 9 mm from apex and were viewed under stereomicroscope. The presence of dentinal defects was noted. STATISTICAL ANALYSIS: Groups were analyzed with the Chi-square test. RESULTS: Significant difference was seen between groups. No defects were found in unprepared roots and those prepared with hand files. ProTaper, K3 rotary, and Easy RaCe preparations resulted in dentinal defects in 23.3%, 10%, and 16.7% of teeth, respectively. More defects were shown in coronal and middle sections, and no defect was seen in apical third. CONCLUSION: The present study revealed that use of rotary instruments could result in an increased chance for dentinal defects as compared to hand instrumentation.