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Aims Diastolic Ca release (DCR) from sarcoplasmic reticulum (SR) Ca release channel ryanodine receptor (RyR2) has been linked to multiple cardiac pathologies, but its exact role in shaping divergent cardiac pathologies remains unclear. We hypothesize that the SR-mitochondria interplay contributes to disease phenotypes by shaping Ca signalling. Methods and results A genetic model of catecholaminergic polymorphic ventricular tachycardia (CPVT2 model of CASQ2 knockout) and a pre-diabetic cardiomyopathy model of fructose-fed mice (FFD), both marked by DCR, are employed in this study. Mitochondria Ca (mCa) is modulated by pharmacologically targeting mitochondria Ca uniporter (MCU) or permeability transition pore (mPTP), mCa uptake, and extrusion mechanisms, respectively. An MCU activator abolished Ca waves in CPVT2 but exacerbated waves in FFD cells. Mechanistically this is ascribed to mitochondria's function as a Ca buffer or source of reactive oxygen species (mtROS) to exacerbate RyR2 functionality, respectively. Enhancing mCa uptake reduced and elevated mtROS production in CPVT2 and FFD, respectively. In CPVT2, mitochondria took up more Ca in permeabilized cells, and had higher level of mCa content in intact cells vs. FFD. Conditional ablation of MCU in the CPVT2 model caused lethality and cardiac remodelling, but reduced arrhythmias in the FFD model. In parallel, CPVT2 mitochondria also employ up-regulated mPTP-mediated Ca efflux to avoid mCa overload, as seen by elevated incidence of MitoWinks (an indicator of mPTP-mediated Ca efflux) vs. FFD. Both pharmacological and genetic inhibition of mPTP promoted mtROS production and exacerbation of myocyte Ca handling in CPVT2. Further, genetic inhibition of mPTP exacerbated arrhythmias in CPVT2. Conclusion In contrast to FFD, which is more susceptible to mtROS-dependent RyR2 leak, in CPVT2 mitochondria buffer SR-derived DCR to mitigate Ca-dependent pathological remodelling and rely on mPTP-mediated Ca efflux to avoid mCa overload. SR-mitochondria interplay contributes to the divergent pathologies by disparately shaping intracellular Ca signalling. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the in-vitro microleakage of traditional micro hybrid composite resin and 0.2% chitosan-incorporated composite resin when restored in Class V cavities using total etch versus self-etch adhesives after storing in artificial saliva for 24 h. Materials and Methodology: Sixty permanent maxillary premolars collected and Class V cavities were prepared on buccal surface of each tooth (dimensions: mesio-distally 3 mm, occluso cervically 2 mm, and depth of 1.5 mm) and restored with Group 1: micro hybrid (30 teeth) and Group 2: chitosan-incorporated composite (30 teeth), which was further subdivided into: (a) 15 teeth using total-etch adhesives. (b) 15 teeth using self-etch adhesives. Next dye extraction test was carried out using spectrophotometer. Results: Comparison within groups: In Group 1: Self-etch demonstrated less microleakage (0.0129) compared with total etch (0.0183). The difference was statistically significant, and in Group 2: No statistically significant difference was found in mean microleakage scores after using either self-etch (0.0118) or total etch adhesives (0.0120). Conclusion: It can be concluded that chitosan-incorporated composite seems to have improved mechanical properties with a stable bond when used with either self-etch or total etch adhesives in addition to being antibacterial. It may be clinically useful in restoring Class V cavities in patients with high caries risk. However, further in vitro and in-vivo studies need to be carried out. [ABSTRACT FROM AUTHOR]

Aim: To evaluate nanoleakage depth and pattern of cervical restorations bonded with different adhesive systems., Materials and Methods: Thirty-six extracted human premolar teeth were used for the study and grouped according to different bonding agents.Group I: fifth generation dentin bonding agent-ONE COAT SL.Group II: sixth generation dentin bonding agent-PARABOND.Group III: seventh generation dentin bonding agent-ONE COAT 7.0.For nanoleakage depth evaluation, 36 teeth were divided into three groups of 12 teeth each, according to adhesive systems used. For each adhesive system, teeth were subdivided into three subgroups of four teeth each, according to storage period, 24 hours, 1 month, and 3 months before the examination. In each tooth, two cavities were prepared (buccal and lingual), each cavity was lined with different adhesive systems and restored using a nanohybrid composite. The restored teeth were then immersed in water bath at temperature 37 o C for intended period of time and then stored in 50% silver nitrate for 24 hours and photo developing solution for 8 hours. After this, the teeth were cut in buccolingual direction and subjected to scanning electron microscope (SEM) analysis for nanoleakage depth analysis., Results: Group II showed the highest nanoleakage at all three periods. At 24 hours, group III showed more leakage than group I (mean = 0.2869 > 0.2506). At 1 month storage period, there was no significant difference in the leakage. At 3 months storage period, group III showed less leakage than group I (mean = 0.5544 < 0.7313)., How to Cite This Article: Bhupanapadu N, Sattar MA, Deb A. Evaluation of Nanoleakage Depth and Pattern of Cervical Restorations Bonded with Different Adhesive Systems. Int J Clin Pediatr Dent 2022;15(3):299-303., Competing Interests: Source of support: Nil Conflict of interest: None, (Copyright © 2022; The Author(s).)

Aim and Objective: To evaluate and compare the microleakage of unmodified microhybrid composite and 0.2% chitosan-incorporated composite in class V cavities restored immediately and after 3 months of storage in artificial saliva., Materials and Methods: Sixty human permanent maxillary premolars were collected and standardized class V cavity prepared on the buccal surface of each tooth with dimensions: mesiodistally 3 mm, occluso cervically 2 mm, and depth of 1.5 mm and restored with microhybrid composite and chitosan-incorporated composite resins respectively and randomly divided: Group I: control-microhybrid composite ( n = 30): (a) 15 teeth tested immediately (b) 15 teeth tested after 3 months. Group II-restored with chitosan + composite ( n = 30): (a) 15 teeth tested immediately (b) 15 teeth tested after 3 months. Specimens were stored in artificial saliva following which a dye extraction test was carried out using a spectrophotometer., Results: There was no statistically significant difference in microleakage score between the chitosan-composite group and unmodified composite group when evaluated immediately after placing the restoration. Microleakage values of the unmodified composite group increased significantly after 3 months of storage in artificial saliva and values of the chitosan-composite group did not differ significantly even after 3 months of storage. Microleakage was seen significantly less in the chitosan-composite group compared to the unmodified composite group after 3 months of storage in artificial saliva., Conclusion: It can be concluded that chitosan-incorporated composite seems to have improved mechanical properties and forms a more stable bond when compared with unmodified microhybrid composite in addition to being antibacterial., Clinical Significance: Considering the advantageous properties of this material, it may be clinically useful in restoring class V cavities in patients with high caries risk. However, further in vitro and in vivo studies need to be carried out., How to Cite This Article: Deb A, Pai V, Nadig RR. Evaluation of Immediate and Delayed Microleakage of Class V Cavities Restored with Chitosan-incorporated Composite Resins: An In Vitro Study. Int J Clin Pediatr Dent 2021;14(5):621-627., Competing Interests: Source of support: Department of Conservative Dentistry and Endodontics, Dayananda Sagar College of Dental Sciences, Bengaluru, Karnataka Conflict of interest: None, (Copyright © 2021; Jaypee Brothers Medical Publishers (P) Ltd.)