Assessment of Apical Extrusion of Debris during Root Canal Preparation with Different Ni-Ti File Systems: An In Vitro Study.

AIM AND OBJECTIVE: The aim of this study was to evaluate the apical extrusion of debris during root canal preparation with the use of different Nickel-Titanium (Ni-Ti) file systems. MATERIALS AND METHODS: Totally 60 single-rooted human mandibular premolar teeth with fully formed roots were chosen for the study. The coronal access cavity and all other preparations were done with the use of an access cavity kit and then 60 samples were randomly separated into three investigational groups (n = 20); group I: self-adjusting file, group II: WaveOne Gold, and group III: Mtwo rotary system. After instrumentation, the teeth were taken out from the tube and the root surface-adherent debris was collected by washing off the apical area of the tooth with distilled water (1 ml) into a centrifuge tube. The centrifuge tube was kept for 5 days in an incubator at 70°C to permit evaporation of the moisture prior to weighing the dry debris with the aid of an electrical analytical balance. RESULTS: The highest quantity of debris extruded was by the Mtwo rotary system (0.0394 ± 0.880) followed by WaveOne Gold (0.0247 ± 1.030) and self-adjusting file (0.0198 ± 0.102). A statistically significant difference (p < 0.001) was found between the various file systems. CONCLUSION: After considering the drawbacks of this study, apical debris extrusion could be found with all three groups. However, the self-adjusting file demonstrated a significantly reduced quantity of apical debris extrusion compared to the Mtwo rotary system and WaveOne Gold. CLINICAL SIGNIFICANCE: The chief step during the procedure of root canal treatment is the preparation of the infected root canals biomechanically. This preparation may lead to forcing the apical debris into the periapical space through the apical foramen, resulting in host-initiated immunological response which leads to postoperative discomfort and pain. This consequently leads to selection of a specific rotary system for endodontic treatment.

Assessment of Remineralization Capacity of Various Remineralizing Agents on Artificial Enamel Lesions Using Confocal Laser Scanning Microscope: An In Vitro Study.

AIM AND OBJECTIVE: The present study aimed at evaluating the effectiveness of diverse remineralizing agents on artificial enamel lesion using confocal laser scanning microscope (CLSM). MATERIALS AND METHODS: Totally 80 mandibular premolars which were single rooted were included. All teeth were suspended in a demineralizing solution to create artificial enamel lesions on the exposed enamel. The samples were separated randomly into four groups (20 each) depending on the application of the remineralizing agents as follows: group 1: control; group 2: calcium sucrose phosphate (CaSP); group 3: fluoride varnish; and group 4: casein phosphopeptides-amorphous calcium phosphate (CPP-ACP). The samples in individual group were treated with the corresponding remineralizing agent (except for the control group) two times a day for 14 days. The experimental and control groups were exposed to CLSM assessment to analyze the data of remineralization and demineralization. RESULTS: The mean depth of remineralization of fluoride varnish group was slightly more compared to other groups. The highest mean depth of remineralization was found in the fluoride varnish group (122.26 ± 0.28) followed by CaSP (110.58 ± 1.34), CPP-ACP (107.08 ± 0.48), and control (157.78 ± 0.46) groups. The different comparisons among the remineralization material groups showed a statistically significant difference (p < 0.05) in almost all groups except group 2 vs group 4. CONCLUSION: This study concluded that improved remineralization of artificial enamel lesion could be achieved with the fluoride varnish group when compared to the CaSP and CPP-ACP groups. CLINICAL SIGNIFICANCE: Remineralization as a treatment technique has received a lot of consideration from clinicians. The process of remineralization and demineralization is considered an active process categorized by the movement of calcium and phosphate in and out of the enamel. Presently, the attention has changed toward increasing the resistance of the tooth by applying remineralizing agents topically, which has led to the notable fall in dental caries.

SEM Evaluation of Various Intracanal Irrigation Devices on Smear Layer Removal: A Comparative Study.

AIM: The present study aimed at assessing the effectiveness of different intracanal irrigation devices on the removal of the smear layer. MATERIALS AND METHODS: The recently extracted 80 lower premolars having single canal were chosen for this in vitro study. A round diamond bur was used to gain endodontic access and the root canal was entered with a #15 K-file until the tip was just seen at the apical foramen. Manual instrumentation of root canals of all teeth was done using the step-back method. The samples were later divided randomly into four groups. Later, each sample was exposed to final irrigation by using four different irrigation systems, group 1: conventional needle irrigation, group 2: irrigation with ultrasonic activation, group 3: irrigation with EndoVac system activation, group 4: irrigation with EndoActivator. The samples were next mounted and visualized under scanning electron microscope (SEM) for the absence or presence of the smear layer. RESULTS: Irrigation with EndoVac system activation showed the presence of least smear layer (2.40 ± 0.32), followed next by EndoActivator (3.24 ± 0.46) and ultrasonic activation (4.96 ± 0.54) and conventional needle irrigation (5.20 ± 0.10). No statistically significant difference was found in the apical and coronal thirds of the root canal in removal of the smear layer on an intragroup comparison. However, a statistically significant (p < 0.001) difference was seen between the groups at the apical and coronal thirds on an intergroup comparison. CONCLUSION: This study demonstrated the EndoVac system group to be efficient in removal of the smear layer when compared to the EndoActivator system, ultrasonic activation, and conventional needle irrigation group. CLINICAL SIGNIFICANCE: The definitive objective of endodontic therapy is to transform the affected teeth to a healthy and functional state. The irrigants can reach the working length when delivered by an effective irrigation delivery system. This type of delivery system should deliver adequate volume of irrigants all the way up to the working length and have sufficient flow and be efficient at debridement of complete canal system.

In Vitro Assessment of Intracanal Calcium Hydroxide Removal Using Various Irrigation Systems: An SEM Study.

AIM: The aim of this research was to assess the effectiveness of three different irrigation systems in elimination of calcium hydroxide [Ca(OH)2]from root canals. MATERIALS AND METHODS: This in vitro research included ninety recently extracted mandibular premolar teeth with a solitary root. The sample teeth were subjected to disinfection employing sodium hypochlorite at 5.25%. The root canal preparation was performed followed by placement of premixed Ca(OH)2 within every canal. The sample teeth were then randomly allocated into one of the three experimental groups (each comprising 30 samples) as follows: Group 1, NaviTip FX irrigation system; group 2, Vibringe sonic irrigation system; and group 3, EndoVac apical negative pressure irrigation system. Following the preparation, each of the sample teeth was examined beneath a scanning electron microscope (SEM) at a magnification of 1000×. RESULTS: An intragroup comparative analysis revealed that the highest Ca(OH)2 elimination was seen at middle third (0.82 ± 0.09, 0.30 ± 0.11) in NaviTip FX irrigation system and Vibringe sonic irrigation system, respectively. Higher Ca(OH)2 was eliminated at the apical third (0.26 ± 0.02) by the EndoVac irrigation system. At coronal third, maximum Ca(OH)2 removal was seen in EndoVac irrigation system (0.49 ± 0.03). A statistically significant difference was noted amid Vibringe sonic irrigation and EndoVac irrigation systems. The intergroup evaluation of Ca(OH)2 elimination at coronal, middle, and apical third showed a statistically significant difference between NaviTip FX irrigation and Vibringe sonic irrigation as well as between NaviTip FX irrigation and EndoVac irrigation at a p value of 0.001. The difference between EndoVac irrigation and Vibringe sonic irrigation was not statistically significant. CONCLUSION: Amid the limitations of this research, this research concludes that none among the irrigation methods employed could totally eliminate the Ca(OH)2 off the root canals. Nevertheless, EndoVac apical negative pressure irrigation has slightly superior potential in eliminating Ca(OH)2 from the root canals in comparison with Vibringe sonic irrigation as well as the NaviTip FX irrigation system. CLINICAL SIGNIFICANCE: Even though the Ca(OH)2 is largely suggested as medicament, its elimination at the point of canal obturation is likewise significant and complex as any remaining portion may avoid sealer diffusion inside the dentinal tubules, consequently substantially escalating the apical leakage of endodontically treated teeth.

Evaluation of Sealing Potential of Different Repair Materials in Furcation Perforations Using Dye Penetration: An In Vitro Study.

AIM: The present study aimed to assess the sealing ability of various repair materials in furcation perforations using dye penetration. MATERIALS AND METHODS: A total of 80 human first molars from mandible with unbroken enamel surfaces, which were extracted completely for periodontal reasons, were chosen. All extracted teeth were kept in a sterile solution up until further use. Endo-access bur was used to prepare endodontic access cavity, and a high-speed long shank round bur was used to create a planned perforation on the floor of pulp. All the specimens were randomly grouped (20 teeth in each group): Group I: control; group II: Pro-Root MTA; group III: resin-modified glass-ionomer cement (RM GIC); and group IV: Biodentin. After placement of repair materials in perforated furcation, the chamber of each tooth was accessed with 2% methylene blue dye. Later, a diamond disk was used to split the teeth buccolingually. A stereomicroscope (10×) was used to visualize the highest dye penetration. RESULTS: The least penetration was seen in teeth repaired by Biodentin group (0.88 ± 0.02), next by Pro-Root MTA group (1.24 ± 0.13) and resin-modified glass ionomer cement group (3.62 ± 0.46). A statistically significant difference was seen among different perforation repair materials by analysis of variance. A statistically significant difference (p value < 0.05) was found between each group, excluding group II v/s group IV. CONCLUSION: This study concluded that reduced dye penetration in perforation repair along the furcations and improved sealing ability are shown by biodentine group in comparison to Pro-Root MTA and resin-modified glass-ionomer cement group. CLINICAL SIGNIFICANCE: Root perforations along the furcation that develop due to the endodontic procedures have a remarkable damaging effect on prognosis and frequently result in loss of secondary periodontal attachment, thus resulting in early loss of the involved tooth. Therefore, the selection of biocompatible repair material aids to enhance the treatment prognosis.

Association of caspases with an increased prostate cancer risk in north Indian population.

Dysregulation of apoptosis plays a crucial role in carcinogenesis. Thus, genetic alterations within caspase genes would be expected to provoke a deficient apoptotic signaling thereby facilitating the development of prostate cancer (PCa). In the present study we investigated whether three different polymorphisms in the caspase-5 and -3 genes are differentially expressed in PCa. In a hospital-based case control study in northern India, we genotyped 192 PCa patients and 225 unrelated healthy controls for caspase-5 (G>C) (T>C) and caspase-3 (G>A) polymorphisms using amplification refractory mutation system and polymerase chain restriction fragment length polymorphism methods. Data were statistically analyzed and variant genotype GG of caspase-3 demonstrated increased risk for PCa (odds ratio [OR]=2.72, p=0.005). Similarly variant allele carrier (AG+GG) (OR=1.53, p=0.034) and G allele (OR=1.54, p=0.005) were also statistically associated with PCa risk. High risk for PCa was also observed with respect to caspase-5 (CC) diplotypes (OR=21.67, p=0.012, Pc=0.048). We observed significantly enhanced risk for PCa due to interaction between caspase-3 and -5 gene polymorphisms. In association of genotypes with clinical characteristics, heterozygous TC genotype of caspase-5 (T>C) conferred risk with high Gleason grade tumor (OR=2.35, p=0.042). In case-only analysis, interaction of environmental risk factors and genotypes did not further modulate the risk for PCa. Our observations suggested positive association of caspase-3 and diplotype analysis of caspase-5 to be associated with PCa risk. Interaction of caspase-3 and -5 genotypes also modulated the PCa risk.