Comparative evaluation of effect of One Coat 7 Universal and Tetric N-Bond Universal adhesives on shear bond strength at resin-zirconia interface: An in vitro study.

Background: Success of all-ceramic restorations depends on their cementation process. Bonding crystalline materials like zirconia to an underlying substrate is challenging. Recently, universal adhesives have been developed. They claim to chemically bond to zirconia due to the presence of compounds like 10-methacryloyloxydecyl dihydrogen phosphate. But for majority of these adhesives, few studies demonstrating their effectiveness are available. Aims: This study aimed to assess the effect of two universal adhesives, One Coat 7 Universal and Tetric N-Bond Universal on shear bond strength at zirconia-resin junction. Materials and Methods: Thirty CAD-CAM milled zirconia cylinders (5 mm × 8 mm) were sandblasted and divided into three groups: Group A (control) received no treatment, while Groups B and C were primed by One Coat 7 Universal and Tetric N-Bond Universal, respectively. They were luted to composite surfaces by a dual-curing resin cement. After 24 h, a shear bond strength test was conducted and failure mode was analyzed. Statistical Analysis: One-way analysis of variance and post hoc Tukey's test were used for statistical analysis. Results: Both One Coat 7 Universal (24.43 ± 2.66 MPa) and Tetric N-Bond Universal (28.61 ± 3.11 MPa) had significantly higher strength than the control group (9.86 ± 2.00 MPa). Control group underwent 100% adhesive failures. Experimental groups had predominantly mixed/cohesive failures. Conclusion: Both universal adhesives increased the bond strength at resin-zirconia junction. Tetric N-Bond Universal exhibited the highest strength.

Reliability of Ultrasonography in differentially diagnosing periapical lesions of endodontic origin in comparison with Intra-oral periapical radiography and Cone-beam computed tomography: An in vivo study.

Background: Periapical granuloma, radicular cyst, and periapical abscess represent periapical changes of frequent occurrence. Addressing this diagnostic dilemma is a matter of great concern, as it aids in governing the treatment planning and predicting its outcome. Aim: To evaluate the comparative accuracy of ultrasonography (USG), intraoral periapical (IOPA) radiography, and cone-beam computed tomography (CBCT) in differentially diagnosing periapical lesions of endodontic origin. Methods: Thirty-five patients having periapical lesions associated with anterior teeth requiring endodontic therapy were included in the study. The lesions were analyzed using IOPA radiographs, CBCT scans, and USG with color Doppler (CD). Periapical surgery ensued and enucleated tissue samples were subjected to histopathological analysis. To evaluate the accuracy, diagnoses made by each of the three modalities were compared with the gold standard histopathological reports, and the diagnostic accuracy, sensitivity, and specificity of each were calculated. Statistical Analysis: Cohen kappa (κ) was used for interrater reliability, and Pearson's contingency coefficient (C) was used for correlating findings of USG with histopathology. Results: USG showed good concordance with histopathological findings (contingency coefficient: 0.664). It also showed a higher accuracy rate compared to IOPA radiography and CBCT in differentially diagnosing periapical lesions. Conclusion: USG with CD holds the potential to be used as a noninvasive adjunct in periapical diagnostics.

Report of a case of platelet-rich fibrin-mediated revascularization of immature 12 with histopathological evaluation.

The procedure of regeneration has shown promising results in the treatment of nonvital teeth with immature apices. However, the tissue being regenerated can only be confirmed through histological examination. This report describes an immature nonvital 12 with apical pathology which was treated via revascularization using 3% NaOCl and 17% ethylenediaminetetraacetic acid as irrigants; Ca(OH)2 as intracanal medicament and platelet-rich fibrin (PRF) as scaffold. On follow-up at 6 and 12 months, healing of periapical lesion, dentinal thickening, and apical closure with a canal exit forming distally were evident. The tooth, however, got fractured and was subsequently extracted at 12 months and sent for histopathological examination. It was revealed that a collagenous matrix for forming hard tissue similar to acellular cementum with a diffuse area of calcification could be seen in pulp space being attached with root canal dentin walls, suggesting that PRF may yield favorable outcomes in regenerative endodontic procedures.

Scanning electron microscopic evaluation of marginal adaptation of AH-Plus, GuttaFlow, and RealSeal at apical one-third of root canals - Part II: Core-sealer interface.

BACKGROUND: Not only the gaps at dentin-sealer interface but also at core-sealer interface may jeopardize the outcome of root canal treatment. AIM: The aim of this in vitro scanning electron microscopic (SEM) study was to determine which root canal sealer among AH-Plus, GuttaFlow, and RealSeal provides a superior marginal adaptation with the core obturating material in the apical third region of root canals. MATERIALS AND METHODS: Selected 30 human freshly extracted maxillary central incisors were biomechanically prepared, then divided equally into three groups and obturated with AH-Plus, GuttaFlow, and RealSeal using single cone obturation technique. After sectioning longitudinally, apical third of the roots were observed under SEM dentin-sealer-core interface was focused. Marginal adaptation and interfacial gaps at core-sealer interface of all the samples were evaluated and analyzed statistically in this part of the article. STATISTICAL ANALYSIS USED: Analysis of variance and post hoc Tukey's test. RESULTS: Mean average gap was significantly higher (P < 0.05) for AH-Plus (15.65 ± 10.48 µm), when compared to GuttaFlow (3.51 ± 1.81 µm) and RealSeal (6.01 ± 2.51 µm). Between RealSeal and GuttaFlow, the latter showed least marginal gap; however, this difference was not statistically significant (P > 0.05). CONCLUSIONS: GuttaFlow is better adapted in the apical third of root canals among 3 sealers.

Scanning electron microscopic evaluation of marginal adaptation of AH-plus, GuttaFlow, and RealSeal at apical one-third of root canals - Part I: Dentin-sealer interface.

BACKGROUND: Complete seal at dentin-sealer-core interface of the root canal is required to maintain long-term periapical health. AIM: The aim of this in vitro scanning electron microscopic (SEM) study was to determine which of the commonly used root canal sealer among AH-Plus, GuttaFlow, and RealSeal provides a superior marginal adaptation with the dentin in the apical third region of root canals. MATERIALS AND METHODS: Selected 30 human freshly extracted maxillary central incisors were biomechanically prepared, then divided equally into three groups and obturated with AH-Plus, GuttaFlow, and RealSeal using single-cone obturation technique. After sectioning longitudinally, apical third of the roots was observed under SEM; dentin-sealer-core interface was focused. Marginal adaptation and interfacial gaps at dentin-sealer interface of all the samples were evaluated and analyzed statistically in this part of the article. STATISTICAL ANALYSIS USED: Analysis of variance and post hoc Tukey's test. RESULTS: GuttaFlow exhibited least average marginal gap of 2.38 ± 1.43 µm, followed by AH-Plus (4.11 ± 2.85 µm) and RealSeal (4.65 ± 3.91 µm) with no significant difference (P > 0.05) among the groups. CONCLUSIONS: As the dentin-sealer interfacial gap is seen to be minimum in GuttaFlow, it is better adapted to dentin in the apical third of root canals compared to AH-Plus and RealSeal.

Reliability of cone beam computed tomography as a biopsy-independent tool in differential diagnosis of periapical cysts and granulomas: An In vivo Study.

BACKGROUND: Differential diagnosis of periapical cysts and granulomas is required as their treatment modalities are different. AIM: The aim of this study was to evaluate the efficacy of cone beam computed tomography (CBCT) in the differential diagnosis of periapical cysts from granulomas. SETTINGS AND DESIGN: A single-centered observational study was carried out in the Department of Conservative Dentistry and Endodontics, Dr. R. Ahmed Dental College and Hospital, using CBCT and dental operating microscope. METHODS: Forty-five lesions were analyzed using CBCT scans. One evaluator analyzed each CBCT scan for the presence of the following six characteristic radiological features: cyst like-location, shape, periphery, internal structure, effect on the surrounding structures, and cortical plate perforation. Another independent evaluator analyzed the CBCT scans. This process was repeated after 6 months, and inter- and intrarater reliability of CBCT diagnoses was evaluated. Periapical surgeries were performed and tissue samples were obtained for histopathological analysis. To evaluate the efficacy, CBCT diagnoses were compared with histopathological diagnoses, and six receiver operating characteristic (ROC) curve analyses were conducted. STATISTICAL ANALYSIS USED: ROC curve, Cronbach's alpha (α) test, and Cohen Kappa (κ) test were used for statistical analysis. RESULTS: Both inter- and intrarater reliability were excellent (α = 0.94, κ = 0.75 and 0.77, respectively). ROC curve with regard to ≥4 positive findings revealed the highest area under curve (0.66). CONCLUSION: CBCT is moderately accurate in the differential diagnosis of periapical cysts and granulomas.

Efficacy of cone beam computed tomography in the detection of MB2 canals in the mesiobuccal roots of maxillary first molars: An in vitro study.

BACKGROUND: Numerous researches have been done on the permanent maxillary first molars for the presence of an extra canal, especially the mesiobuccal roots for the presence of MB2 canals. Cone beam computed tomography (CBCT) has been used recently in the detection of these canals. However, literature discussing the efficacy and reliability of CBCT in the detection of these canals is scanty. AIMS: This study aims to evaluate the efficacy of CBCT as a preoperative diagnostic aid in locating the second mesiobuccal canal in maxillary first molars. METHODS: Selected sixty extracted maxillary first molars were placed in the skull base, and CBCT scans were done for evaluating the presence of MB2 canals in the mesiobuccal root. Sectioning of the roots at 3, 5, and 7 mm from the tip was performed and further examined under the microscope for the presence of the MB2 canals. Evaluations were done by two evaluators independently. Results of evaluations were statistically analyzed. Statistical analysis used were standard normal deviation (Z value), interrater reliability (Chronbach's alpha-), P value and receiver operating curve(ROC). RESULTS AND CONCLUSIONS: Detection rates of MB2 using both the methods did not show any significant difference (P > 0.05). CBCT was found to be a reliable tool for the detection of MB2 canal in maxillary first molar teeth when compared to gold standard sectioning technique.

An ex-vivo comparative study of root-end marginal adaptation using grey mineral trioxide aggregate, white mineral trioxide aggregate, and Portland cement under scanning electron microscopy.

CONTEXT: Where nonsurgical endodontic intervention is not possible, or it will not solve the problem, surgical endodontic treatment must be considered. A major cause of surgical endodontic failures is an inadequate apical seal, so the use of the suitable substance as root-end filling material that prevents egress of potential contaminants into periapical tissue is very critical. AIMS: The aim of the present ex-vivo study was to compare and evaluate the three root-end filling materials of mineral trioxide aggregate (MTA) family (white MTA [WMTA], grey MTA [GMTA] and Portland cement [PC]) for their marginal adaptation at the root-end dentinal wall using scanning electron microscopy (SEM). MATERIALS AND METHODS: Sixty human single-rooted teeth were decoronated, instrumented, and obturated with Gutta-percha. After the root-end resection and apical cavity preparation, the teeth were randomly divided into three-experimental groups (each containing 20 teeth) and each group was filled with their respective experimental materials. After longitudinal sectioning of root, SEM examination was done to determine the overall gap between retrograde materials and cavity walls in terms of length and width of the gap (maximum) at the interface. Descriptive statistical analysis was performed to calculate the means with corresponding standard errors, median and ranges along with an analysis of variance and Tukey's test. RESULTS: The least overall gap was observed in GMTA followed by PC and WMTA. While after statistically analyzing the various data obtained from different groups, there was no significant difference among these three groups in terms of marginal adaptation. CONCLUSION: GMTA showed the best overall adaptation to root dentinal wall compared to PC and WMTA. Being biocompatible and cheaper, the PC may be an alternative but not a substitute for MTA.