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Objective: The aim was to compare the "reverse sandwich restoration" to resin composite restorations regarding marginal adaptation, fracture resistance, favourable/unfavourable fractures in the management of external cervical resorption. Methods: Forty-eight extracted maxillary central incisors were selected and endodontically treated. Cervical regions of the labial root surfaces received simulated resorptive defects and were restored as three randomly allocated groups: Reverse Sandwich Restoration (resin composite + resin-modified glass ionomer) (RSR); resin composite restoration (COMP), and no restoration (NR). Each group was further divided into two subgroups (n=8 each): Thermomechanical Aging (TA) (equivalent to one year) and No Aging (NA). Marginal adaptation was scored by scanning electron microscopy. Fracture resistance was tested using a universal testing machine. Favourable versus unfavourable fractures were classified based on fracture extent. Results: TA decreased the marginal adaptation for both RSR and COMP. Mean fracture resistance per groups were: RSR-NA 1522.4±94.9N, RSR-TA 939.6±72.9N, COMP-NA 1197.6±95.7N, COMP-TA 870.4±86.3N, NR-NA 1057.1±88.1N, and NR-TA 836.6±81.9N, respectively. Fracture resistance was the highest for RSRNA compared to all other groups (p<0.05). TA decreased the fracture resistance in all groups (p<0.05), there was no significant difference between RSR and COMP regarding fracture resistance and favourable/unfavourable fractures (p>0.05). Conclusion: RSR provided comparable results to resin composite fillings to restore artificial cervical defects pertaining to marginal adaptation, fracture resistance, and favourable versus unfavourable fractures. RSR is preferable due to its inherent biocompatibility to the periodontium. [ABSTRACT FROM AUTHOR]

Aim: Several factors influence the condition of the periapical tissues associated with root filled teeth. The primary objective of this study was to retrospectively evaluate the extent and speed of bone healing of large periapical lesions associated with nonsurgical root canal treatment or retreatment. The secondary objective was to analyse the relationship between the time to complete healing when analysed using cone beam computed tomography (CBCT) and other possible predictors that affect healing. Methodology: Seventy‐nine patients were treated during the years 2013–2020 with large periapical lesions of endodontic origin (10–15 mm) as observed on intraoral periapical radiographs (IOPAR) were included. IOPAR and CBCT were available before treatment and during the follow‐up (IOPAR every 6 months and CBCT every 12 months). The volume of periapical lesions was calculated by OsiriX Lite software. Variables such as initial volume of the lesion, age, gender, type of treatment or type of root canal filling were compared to identify the differences between healed and unhealed lesions. Pearson's Chi‐square test was used for categorical variables, the t‐test for age and the Wilcoxon test for initial volume of the lesion. The association between time to healing and the variables was assessed using univariate analysis and multivariate analysis. The Wilcoxon test was used to observe the association of healing time with categorical variables and the correlation index was measured with the quantitative variables. Results: Of the 79 cases analysed, 60 lesions (76%) were completely healed as verified by CBCT in a mean healing time of 19 months, of which 60% healed fully between 12 and 18 months. Increase in age of patient and larger initial volume of the lesion were associated with a significantly longer healing time (p <.001). Gender, filling material and type of treatment did not have a significant effect on the healing process (p >.05). Conclusions: Clinicians should be aware that periapical lesions in older patients and larger areas of bone loss take longer to heal. CBCT monitoring of large periapical lesions is critical and it can help clinicians in the decision‐making process. [ABSTRACT FROM AUTHOR]

Purpose: Preschool children with early childhood caries (ECC) frequently exhibit extreme dental anxiety and fear, posing a considerable challenge to paediatric dentists for their treatment. The aim of this study was to evaluate the influence of silver diamine fluoride (SDF) treatment on the oral health-related quality of life (OHRQoL) of uncooperative preschool children using an Arabic version of the Early Childhood Oral Health Impact Scale (A-ECOHIS). Materials and Methods: A pre-validated A-ECOHIS was used to assess the sensitivity and responsiveness. Fiftyone children, uncooperative with conventional dental care, underwent SDF treatment; their mothers answered the A-ECOHIS before and 4 weeks after treatment. Based on the global transition rating (GTR), the mothers rated their child's oral health condition following SDF treatment. Results: SDF effectively arrested caries after 4 weeks in all children. There was a statistically significant reduction in mean scores of the total A-ECOHIS, child impact scale and family impact scores at follow-up (Wilcoxon signedrank test; p = 0.001). There were statistically significant changes in the mean GTR of children's oral health. Conclusions: A-ECOHIS was sensitive and responsive to SDF treatment. SDF statistically significantly improved the OHRQoL of uncooperative preschool children. [ABSTRACT FROM AUTHOR]

Context: Recent introduction of shape memory (SM) nickel-titanium (NiTi) alloy into endodontics is a major breakthrough. Although the flexibility of these instruments was enhanced, fracture of rotary endodontic instruments during instrumentation is an important challenge for the operator. Implementation of supplementary manufacturing methods that would improve the fatigue life of the instrument is desirable. Aim: The purpose of this study was to investigate the role of dry cryogenic treatment (CT) conditions on the microstructure of martensitic SM NiTi alloy. Materials and Methods: Experiments were conducted on Ni-51 wt% Ti-49 wt% SM alloy. Five cylindrical specimens and five sheet specimens were subjected to different CT conditions: Deep CT (DCT) 24 group: -185°C; 24 h, DCT 6 group: -185°C; 6 h, shallow CT (SCT) 24 group: -80°C, 24 h, SCT 6 group: -80°C, 6 h and control group. Microstructure of surface was observed on cylindrical specimens with an optical microscope and scanning electron microscope at different magnifications. Subsurface structure was analyzed on sheet specimens using X-ray diffraction (XRD). Results: Microstructures of all SM NiTi specimens had equiaxed grains (approximately 25 μm) with well-defined boundaries and precipitates. XRD patterns of cryogenically treated specimens revealed accentuation of austenite and martensite peaks. The volume of martensite and its crystallite size was relatively more in DCT 24 specimen. Conclusions: DCT with 24 h soaking period increases the martensite content of the SM NiTi alloy without altering the grain size. [ABSTRACT FROM AUTHOR]

Context: Evaluation of microhardness of root dentin provides indirect information on the change in mineral content of root dentin thereby providing useful information on the bonding quality of resin-based root canal sealers. Aims: This study evaluated the effect of 17% EDTA, MTAD, and 18% HEBP solutions on the microhardness of human root canal dentin using the Vickers microhardness test. Materials and Methods: Forty human single-rooted teeth were decoronated at the cementoenamel junction and sectioned longitudinally into buccal and lingual segments. Eighty specimens were divided into four groups (n=20). Group I was treated with distilled water (control), groups II, III, and IV were treated with 1.3% NaOCl as a working solution for 20 minutes followed by 17% EDTA, MTAD, and 18% HEBP respectively. The surface hardness of the root dentin was determined in each specimen with a Vicker's hardness tester. The values were statistically analyzed using the one-way ANOVA and post hoc Tukey multiple comparison tests. Results: There was a statistical significant difference among all the groups (one-way ANOVA; P<0.001). Among the experimental groups, HEBP showed the highest dentin microhardness (53.74 MPa, P<0.001). Least microhardness was found with MTAD (42.85 MPa, P<0.001). Conclusions: HEBP as a final rinse appears to be a promising irrigation protocol with less impact on the mineral content of root dentin. [ABSTRACT FROM AUTHOR]

The study evaluated the compatibility of chloroform, ether, and xylene with poly(dimethyl siloxane) (PDMS) based sealer. Freshly mixed sealer was placed in 90 glass molds with 5 mm diameter and 2 mm thickness. All samples were stored in 75% relative humidity at 37°C for 2 weeks. All the samples were divided into three groups: group A – chloroform; group B – ether, and group C – xylene and immersed in fresh solvent at room temperature. The specimens were weighed before and after immersion for each group at the end of 2, 5, and 10 min. The swelling ratio was calculated for all the groups. Intergroup comparison revealed no difference in the mean swelling ratio for 2, 5, and 10 min (P > 0.001; Tukey HSD Post Hoc). Intragroup comparison revealed significant difference in swelling ratio between 2 and 5 min for group B and group C (P < 0.001; Paired t test). Ether has the highest compatibility with PDMS-based sealer after 2 min followed by xylene after 5 min. [ABSTRACT FROM AUTHOR]

This case report explains about an innovative treatment strategy for the management of damaged anterior teeth with reduced incisal clearance by means of a single-unit all-ceramic post-core-crown zirconia ceramic restoration fabricated by Computer-aided designing and computer-aided manufacturing (CAD/CAM) technology. The reinforced zirconia ceramics allow fabrication of durable esthetic restorations in cases with high functional loading and the unification of the post, core, and crown in a single unit decreases the frequency of failure by creating a monobloc effect. In addition, the use of CAD/CAM technology for designing and fabricating ceramic restorations offers the option of expeditiously preparing these high-strength all- ceramic restorations. [ABSTRACT FROM AUTHOR]

Purpose: Preschool children with early childhood caries (ECC) frequently exhibit extreme dental anxiety and fear, posing a considerable challenge to paediatric dentists for their treatment. The aim of this study was to evaluate the influence of silver diamine fluoride (SDF) treatment on the oral health-related quality of life (OHRQoL) of uncooperative preschool children using an Arabic version of the Early Childhood Oral Health Impact Scale (A-ECOHIS)., Materials and Methods: A pre-validated A-ECOHIS was used to assess the sensitivity and responsiveness. Fiftyone children, uncooperative with conventional dental care, underwent SDF treatment; their mothers answered the A-ECOHIS before and 4 weeks after treatment. Based on the global transition rating (GTR), the mothers rated their child's oral health condition following SDF treatment., Results: SDF effectively arrested caries after 4 weeks in all children. There was a statistically significant reduction in mean scores of the total A-ECOHIS, child impact scale and family impact scores at follow-up (Wilcoxon signedrank test; p ˂ 0.001). There were statistically significant changes in the mean GTR of children's oral health., Conclusions: A-ECOHIS was sensitive and responsive to SDF treatment. SDF statistically significantly improved the OHRQoL of uncooperative preschool children.

The present review provides an insight into various potential areas of dentistry that are being invaded by nanotechnology based drugs and drug delivery systems. Current treatments for diseases of dental and oral structures rely on the use of classical pharmacological agents which, in some cases are limited by low efficacy and lack of selectivity to target cells. However, various nanostructures in drug delivery and their challenges in the field of dentistry have not been reviewed so far in the literature. The different treatment opportunities of importance include caries control restorations, tooth remineralisation, management of dentinal hypersensitivity, dental caries vaccine, management of oral biofilm, root canal disinfection, local anaesthesia and periodontal infection. The authors have also identified few dental applications demanding extensive research to emerge as a promising therapeutic strategy. We conclude by claiming that dentistry should follow the trend of probing matter at nanoscale to achieve a predictable treatment outcome.