Comparative evaluation of hand and rotary file systems on dentinal microcrack formation during pulpectomy procedure in primary teeth: an in vitro study.

PURPOSE: Pulpectomy can be used for the management of deep dentinal carious lesions in primary teeth which can be restored. Mechanical preparation of root canals can be performed using hand or NiTi rotary files. However, this may cause dentinal stress and consequently dentinal microcracks. Hence, the aim was comparative evaluation of hand and rotary file systems on dentinal microcrack formation during pulpectomy procedure in primary teeth. METHODS: 60 extracted primary molar teeth were selected comprising of 80 root canals. Simple random sampling was used to divide root canals into four groups (n = 20): Group A-Hedstrom file, Group B-Pro AF Baby Gold rotary, Group C-ProTaper Next rotary, and Group D-unprepared group. Assessment was conducted on presence or absence of microcracks using Chi square test (p < 0.05). RESULTS: The total number of microcracks in Group A: one (5%), Group B: four (20%), Group C: nine (45%) and Group D: zero (0%) which was statistically significant (p = 0.002). At cervical third, the number of microcracks seen with Group A: one (5%), Group B: zero (0%), Group C: five (25%) and Group D: zero (0%) (p = 0.005). At the middle third, the number of microcracks seen in Group A: zero (0%), Group B: four (20%), Group C: four (20%) and Group D: zero (0%) (p = 0.029). CONCLUSION: The study concluded that dentinal microcracks are formed with both hand and rotary file systems in primary teeth. ProTaper Next showed significantly higher number of microcracks, followed by ProAF Baby Gold and H files.

Comparative evaluation of shear bond strength of three different glass ionomer cement (conventional, zirconium-reinforced and advanced glass hybrid) in primary molars: an in vitro study.

PURPOSE: The success of restorative materials is largely dependent on their capacity to adhere to the tooth structure and withstand the various forces present in the oral cavity. So, the aim of present study was to evaluate and compare the shear bond strength (SBS) of Type IX Glass Ionomer Cement (GIC), Zirconomer, and Gold Label Hybrid GIC in primary molars. METHODS: Thirty primary molars were selected based on inclusion and exclusion criteria. The molars were polished to provide a flat dentin surface after being inserted in auto polymerizing acrylic resin. The samples were randomly divided into three groups, equally and were bonded to GIC. On the dentin surface, restoration cylinders were made using a plastic mould that had an internal diameter and height of 5 mm and 3 mm, respectively. The cement was manipulated according to the manufacturer's directions through the plastic mould. Then, the samples were stored at room temperature for 10 days to mimic oral conditions. The Universal Testing Machine was used to test SBS. One-way ANOVA and the post hoc Tukey test were used to statistically assess the collected data. RESULTS: A statistically significant difference was found in all three groups (p < 0.01), with Zirconomer demonstrating highest SBS, followed by Type IX GIC and Gold Label Hybrid GIC. CONCLUSION: The SBS value of Zirconomer was better when compared to Type IX GIC and Gold Label Hybrid GIC.

Comparative in vitro evaluation of remaining dentine thickness following instrumentation with hand and rotary endodontic files during pulpectomy in primary molars: a systematic review.

PURPOSE: The aim was to compare the remaining dentine thickness (RDT) following instrumentation with hand and rotary endodontic files during pulpectomy in primary molars. Research question was 'Is there any difference between the remaining dentine thickness following instrumentation with hand and rotary endodontic files during pulpectomy in primary molars?'. METHODS: Electronic Databases like MEDLINE PubMed, Cochrane Library, EBSCOhost, Google scholar and grey literature were searched between January 1, 2006 and August 31, 2022 for in vitro and ex vivo studies that compared hand and rotary endodontic instrumentation to evaluate the RDT in primary molars. Articles published in English or which could be translated into English were searched. Two reviewers independently selected studies, extracted data, assessed risk of bias using the Revised, validated version of MINORS criteria. RESULTS: Twelve studies were included in qualitative analysis. All included studies showed low risk of bias. Six studies showed more RDT with rotary instrumentation compared to manual instrumentation. Whereas, five studies showed variable results for RDT with manual and rotary instrumentation at different levels of root canals. One study showed no significant difference between manual and rotary instrumentation. In view of methodological heterogeneity of the findings, a meta-analysis was not conducted. CONCLUSION: High quality of evidence based on low risk of bias was found in all the included studies. Statistically, rotary instrumentation showed more RDT than manual instrumentation according to majority of studies. Despite the shortcomings of this systematic review, it is possible to infer that the use of rotary instrumentation provides more RDT and thus there is considerable conservation of tooth structure.

Comparative evaluation of micro-leakage of two newer glass ionomer cements in primary molars immersed in three beverages: in vitro study

Introduction: The dietary habits of children expose the oral cavity to challenging environments. A durable interface between the restorative material and tooth surface is essential to ensure marginal integrity thereby contributing to the longevity of restoration. Objectives: The objective of this study was to compare the micro-leakage of two newer glass ionomer cements (SDI Riva Self Cure GIC and GC Fuji IX GP EXTRA) in primary molars immersed in sugarcane juice, chocolate milk and mango drink. Methods: The study included 60 extracted non carious upper and lower primary molars. The buccal and lingual surfaces were restored with SDI Riva Self Cure GIC and GC Fuji IX GP EXTRA respectively. The sample was divided into three groups (chocolate milk, mango drink, sugarcane juice). Each group (n=18) was further subdivided into three subgroups based on the immersion regime. Six teeth were kept as control. The teeth were immersed in Rhodamine B dye. Following this, micro-leakage was determined under 40 x stereomicroscope. Results: Both the materials showed micro leakage when immersed in the three beverages. When specimen under each group were compared, the microleakage score increased with an increase in immersion frequency. This was not statistically significant. The microleakage values for both the materials immersed in the three beverages were not significant. Conclusions: Both the materials used in this study can be conveniently used in restoration of primary molars.