Impact of Root Canal Taper on Fracture Resistance of Endodontically Treated Teeth Prepared by Hero Shaper and RaCe File Systems: An In-vitro Study

Introduction: Tooth fracture is one of the most undesirable phenomena in Endodontically Treated Teeth (ETT) and usually leads to tooth extraction. Basically, removal of any hard tissue from the canal walls raises the chance of root fracture. Aim: To evaluate the impact of root canal taper on fracture resistance of ETT prepared by two different file systems (Hero Shaper and RaCe file systems). Materials and Methods: This in-vitro study was conducted in the Department of Conservative Dentistry and Endodontics at Bharati Vidyapeeth (Deemed to be University) Dental College and Hospital, Sangli and Praj Metallurgical Laboratory Pune, Maharashtra, India, frome February 2021 to November 2021. The study included 44 freshly extracted mandibular premolar teeth were randomly divided into four groups. Group 1a had Hero Shaper 4%, group 1b had 6% Hero Shaper, group 2a had RaCe 4% and group 2b had RaCe 6% file system. After cleaning and shaping the root canals, obturation was completed using cold lateral compaction and root canals were embedded in standardised autopolymerising acrylic resin blocks, subjected to a vertical load in universal testing machine to cause vertical root fracture. The forces required to induce fractures were measured in Newtons. Data was analysed by using independent t-test and two-way Analysis of Variance (ANOVA) test for intergroup comparison. A p-value≤0.05 was considered as statistically significant. Results: Among instrumented groups, group 1a (Hero Shaper 4%) showed higher fracture resistance of 372.5 Newtons and group 2b (RaCe 6%) showed lowest fracture resistance of 314.56 Newtons as compared to other groups. Statistically significant difference (p-value=0.026) was seen in the mean fracture resistance among the group 1a and 1b, and group 2a and 2b. At pair wise comparison there was statistically significant difference in group 1a and group 2a (p-value=0.016). Conclusion: Amongst the instrumented groups, Hero Shaper file system showed the higher fracture resistance, than RaCe file system. Marked reduction in fracture resistance of ETT was seen with the use of greater taper instruments.

Evaluation of Shear Bond Strength of Incremental Layer of Self-etch Self-adhesive Novel Flowable Composite after Salivary Contamination: An In-vitro Study

Introduction: Contamination of composite restoration during incremental placement leads to decrease in the incremental bond strength. Adhesive application on freshly contaminated resin surface increases the bond strength but is a complex and time-consuming procedure. Recently composite systems combining etchant, bonding agent and flowable composite into a single component have been introduced to simplify bonding and save time. In this study incremental layer shear bond strength is utilised to assess bond stability at resin-resin interface after salivary contamination. Aim: To evaluate shear bond strength of incremental layer of self-etch self-adhesive novel flowable composite after salivary contamination. Materials and Methods: The present in-vitro study included 55 acrylic resin cylinders (2×2.5 cm) with square shaped cavity (5×5 mm, thickness 2 mm) restored with DMGTM CONSTIC flowable composite that were randomly divided into five groups with eleven specimens per group. Group I: No salivary contamination, Group II: Salivary contamination followed by air drying, Group III: Salivary contamination followed by rinsing and air drying. Group II and III were subdivided into subgroup a: application and brushing of 0.5 mm of CONSTIC followed by light curing and filling of rest of mold by CONSTIC, subgroup b: direct application of 2 mm of CONSTIC. Shear bond strength between increments of composite was determined by Universal Testing Machine. Data were analysed using One-way ANOVA test and Independent t-test. Level of significance was kept at 5%. Results: Incremental shear bond strength (MPa) was highest for group I (12.09±1.99) followed by group IIIa (10.21±3.49), group IIa (10.08±3.21), group IIb (7.59±2.31) and lowest for group IIIb (7.35±3.06). Conclusion: Active application of self-etch self-adhesive flowable composite successfully restores the incremental shear bond strength after salivary contamination.

A comparative evaluation of the antibacterial efficacy of Thymus vulgaris, Salvadora persica, Acacia nilotica, Calendula arvensis, and 5% sodium hypochlorite against Enterococcus faecalis: An in-vitro study

Objectives:

The aim of this study is to evaluate and compare the antibacterial efficacy of Thymus vulgaris, Salvadora persica, Acacia nilotica, Calendula arvensis, and 5% sodium hypochlorite against Enterococcus faecalis.

Methodology:

Herbal extracts of T. vulgaris, S. persica, A. nilotica and C. arvensis were prepared. Tryptone soya broth was used to grow E. faecalis and agar plates were prepared. The tested solutions (Group A: 5% NaOCl, Group B: 20% T. vulgaris, Group C: 12.5% S. persica, Group D: 10% A. nilotica, Group E: 10% C. arvensis) were added to the wells made on agar media. Agar diffusion test was performed. Plates were incubated at 37°C for 24 h. Bacterial zones of inhibition were recorded.

Results:

The data were analyzed statistically by Analysis of Variance (ANOVA) and post hoc comparison by Tukey's t-test. The highest zone of inhibition against E. faecalis was shown by 5% NaOCl, followed by 10% C. arvensis, 20% T. vulgaris and 10% A. nilotica showed similar comparable antibacterial activity. The least zone of inhibition was showed by S. persica.

Conclusion:

5% NaOCl showed the maximum antibacterial activity, and herbal products demonstrated significant antibacterial activity against E. faecalis and can be employed as an alternative to NaOCl.

A comparative evaluation of anesthetic efficacy of articaine 4% and lidocaine 2% with anterior middle superior alveolar nerve block and infraorbital nerve block: An in vivo study

BACKGROUND

The ideal maxillary injection should produce a rapid onset of profound pulpal anesthesia for multiple teeth from a single needle penetration. The main objective is to compare the efficacy of articaine 4% and lidocaine 2% and to compare anterior middle superior alveolar nerve block (AMSANB) and infraorbital nerve block (IONB) for anesthesia of maxillary teeth.

MATERIALS AND METHODS

Forty patients undergoing root canal treatment of maxillary anteriors and premolars were included and randomly divided into four groups of ten each. Group I: patients receiving AMSANB with articaine, Group II: Patients receiving IONB with articaine, Group III: Patients receiving AMSANB with lidocaine, Group IV: Patients receiving IONB with lidocaine. The scores of onset of anesthesia and pain perception were statistically analyzed.

RESULTS

Onset of action was fastest for articaine with AMSANB and slowest for lidocaine with IONB by Tukey's test. A significant change was observed in the electrical pulp test readings at onset and at 30 min by paired t-test. All patients experienced mild pain during the procedure recorded by visual analog scale.

CONCLUSION

Articaine 4% proved to be more efficacious than lidocaine 2%, and AMSANB was more advantageous than IONB in securing anesthesia of maxillary anteriors and premolars.

Albright hereditary osteodystrophy: a case report

A dental practitioner with an eagle's eye can diagnose many hidden disease through careful examination of the oral cavity. One such hereditary metabolic disorder is Albright hereditary osteodystrophy (AHO). Characteristic presentations in an individual affected by AHO were short stature, obesity and brachydactyly especially of 4(th) and 5(th) digits, which are the phenotypic features of genetic mutation. Pseudohypoparathyroidism (PHP) is characterized by inability of the body to respond appropriately to parathormone, mainly characterized by hypocalcemia, increased serum parathormone concentration, insensitivity to the biological activity of parathormone and hyperphosphatemia. AHO when seen in association with resistance to parathormone (PTH), it is called PHP. Here is, a case report of 32-year-old male patient with AHO with distinctive physical characteristics and oral manifestations.

Decontamination methods used for dental burs - a comparative study

AIMS AND OBJECTIVES

Infection control and modes of sterilizations are the key factors to avoid cross transmission of infection in the field of dentistry. Transmission of disease or infection is noted with improper sterilization of reused instruments. Dental burs are the most important tool in any endodontic or conservative procedures of teeth involving tooth contouring, restorative filling procedures and endodontic procedures. Hence, the present study is undertaken to assess the efficacy of different methods of sterilization or decontamination which are routinely used in dental clinics.

MATERIALS AND METHODS

For the present study 96 round diamond burs were selected and divided into 6 groups. These burs were used for the access cavity preparation to get contamination and subjected for bacteriological culture. After getting base line date burs were subjected to manual scrubbing, hot air oven, glass bead sterilizer, ultrasonic cleaner and autoclave to get post decontamination data.

RESULTS

The study revealed that mean colony forming units/ml of Streptococcus mutans decreased maximum for autoclave with 80% reduction, for Lactobacilli 76% reduction and for Candida albicans maximum reduction seen for glass bead sterilizer with 74%.

CONCLUSION

Findings of our study revealed that none of the methods used were found to be absolutely efficacious in the decontamination of dental burs. However, among the experimental groups used in the present study, autoclave was found to be the relatively best method.

Green teeth associated with hyperbilirubinemia: a case report

BACKGROUND

Green stain is an uncommon clinical condition associated with deposition of bilirubin in the dental hard tissues. The staining of the teeth is due to hyperbilirubinemia caused by systemic conditions.

CASE REPORT

The purpose of this report is to present a case of green teeth of the primary dentition in a 17-month old girl associated with hydrocephalus and Hirschprung's disease.

CONCLUSION

The clinical characteristics of the teeth may help in the diagnosis of current or past systemic diseases.

Use of clinical bleaching with 35% hydrogen peroxide in esthetic improvement of fluorotic human incisors in vivo

AIM

The aim of the study was to evaluate esthetic improvement with the use of 35% hydrogen peroxide clinical bleaching as related to the different grades of enamel fluorosis in vivo and to study adverse effect of clinical bleaching with 35% hydrogen peroxide on teeth and gingiva.

MATERIALS AND METHODS

A total of 60 children of different grades of fluorosis were included in the study. With 35% hydrogen peroxide-based dual activated bleaching system, in-office vital teeth bleaching was carried out for each subject. Clinical evaluation for improvement in esthetics, effect on teeth and gingiva were performed for each child during preoperative, immediate postoperative and later 6 months postoperative period. For evaluation and comparison, all the collected data were subjected to statistical analysis.

RESULTS

Although in all the subjects, partial shade relapse was seen over a period of time, good homogeneous and esthetic results were seen in very mild and mild cases. A total of 35% hydrogen peroxide in-office bleaching has no adverse effect on teeth and gingiva.

CONCLUSION

Comparing all the three groups who participated in the study, 35% hydrogen peroxide in-office bleaching seems to be very effective in very mild and mild forms of fluorosis.

CLINICAL SIGNIFICANCE

In very mild and mild forms of fluorosis, in-office vital tooth bleaching with 35% hydrogen peroxide is the most conservative and effective approach in esthetic improvement.