Background:Prosthetic precision can be affected by several variables, such as restorative materials, manufacturing procedures, framework design, cementation techniques and aging. Marginal adaptation is critical for long-term longevity and clinical success of dental restorations. Marginal misfit may lead to cement exposure to oral fluids, resulting in microleakage and cement dissolution. As a consequence, marginal discrepancies enhance percolation of bacteria, food and oral debris, potentially causing secondary caries, endodontic inflammation and periodontal disease.Objective:The aim of the present in vitro study was to evaluate the marginal and internal adaptation of zirconia and lithium disilicate single crowns, produced with different manufacturing procedures.Methods:Forty-five intact human maxillary premolars were prepared for single crowns by means of standardized preparations. All-ceramic crowns were fabricated with either CAD-CAM or heat-pressing procedures (CAD-CAM zirconia, CAD-CAM lithium disilicate, heat-pressed lithium disilicate) and cemented onto the teeth with a universal resin cement. Non-destructive micro-CT scanning was used to achieve the marginal and internal gaps in the coronal and sagittal planes; then, precision of fit measurements were calculated in a dedicated software and the results were statistically analyzed.Results:The heat-pressed lithium disilicate crowns were significantly less accurate at the prosthetic margins (p<0.05) while they performed better at the occlusal surface (p<0.05). No significant differences were noticed between CAD-CAM zirconia and lithium disilicate crowns (p>0.05); nevertheless CAD-CAM zirconia copings presented the best marginal fit among the experimental groups. As to the thickness of the cement layer, reduced amounts of luting agent were noticed at the finishing line, whereas a thicker layer was reported at the occlusal level.Conclusion:Within the limitations of the present in vitro investigation, the following conclusions can be drawn: the recorded marginal gaps were within the clinical acceptability irrespective of both the restorative material and the manufacturing procedures; the CAD-CAM processing techniques for both zirconia and lithium disilicate produced more consistent marginal gaps than the heat-pressing procedures; the tested universal resin cement can be safely used with both restorative materials.

We suggest to screen sleep disturbances in patients with oral lichen planus because they could be considered a prodromal symptoms of mood disorders.

Objectives To evaluate the oral health‐related quality of life (OHRQoL) of patients with burning mouth syndrome (BMS) by comparing the Oral Health Impact Profile‐14 (OHIP‐14) and Geriatric Oral Health Assessment Index (GOHAI) tests, assessing their dependence with pain, anxiety and depression and, secondly, to analyse the changes in time after treatment with psychotropic drugs. Methods Twenty‐six patients and 26 controls were included. The GOHAI, OHIP‐14, visual analogue scale (VAS) and the Hamilton Rating Scales for Depression and Anxiety (HAM‐D and HAM‐A) were performed at baseline (time 0) and after 6 months of treatment (time 1). Descriptive statistics, the Mann‐Whitney non‐parametric test for two independent samples and the Wilcoxon non‐parametric test for two paired samples were used. Results The scores from all outcome measurements were statistically significantly different between the cases and controls (P < .001) with a strong correlation between the GOHAI and the OHIP‐14 (P < .001). The BMS patients showed a statistically significant improvement in the VAS, HAM‐D and HAM‐A scores from time 0 to time 1 (P < 0.001), and in the OHIP‐14 scores (P < .004**) after the treatment, but no statistically significant difference in the GOHAI score (.464). Conclusions Burning mouth syndrome patients showed poorer scores on all scales compared to the healthy subjects with a lower OHRQoL. OHIP‐14 gives a greater weight to psychological and behavioural outcomes in evaluating oral health than GOHAI, and therefore, it is a more effective questionnaire in terms of the evaluation of the treatment response. The management of BMS can improve pain, anxiety and depression and the OHRQoL.

This study investigated the effect of ultrasonic activation of intracanal‐heated sodium hypochlorite (NaOCl) on its dentinal tubular penetration and root canal cleanliness in vitro. In experiment 1, mandibular premolars were randomly allocated to three groups (n = 8): group A, ultrasonic activation; group B, ultrasonic activation of intracanal‐heated NaOCl and group C, syringe‐and‐needle irrigation. Penetration of the fluorescent‐labelled NaOCl was investigated using light microscopy. In experiment 2, mandibular premolars were randomly allocated to group B or C (n = 10), for histological analysis of the remaining pulp tissue and debris. Data were statistically analysed using Kruskal–Wallis and Mann–Whitney tests (P = 0.05). The highest penetration of NaOCl was observed in group B, followed by group A (P < 0.05). Group B showed significantly less amount of debris than group C (P < 0.05). Dentinal tubule penetration of NaOCl and root canal cleanliness were significantly improved by ultrasonic activation of intracanal‐heated NaOCl.

Introduction:The aim of this study is to evaluate the surface of root canals dentine using scanning electron microscope (SEM) after instrumentation with rotary Nickel-Titanium systems and two different protocols of activation of sodium hypochlorite (NaOCl) (extracanal heating at 50°C and intracanal heating at 180°C), to assess the presence/absence of smear layer and also the presence/absence of open dentinal tubules along the walls at the coronal, middle, and apical third of each sample.Materials and Methods:Thirty-six single-rooted teeth were selected, divided into three groups and shaped with ProTaper Universal instruments following irrigation protocols with 5.25% NaOCl. At the end of the preparation, three different protocols of activation were used: nonheated NaOCl in Group A, extra-canal heated NaOCl at 50°C for Group B and intracanal heated NaOCl at 180°C for Group C. Specimens were cut longitudinally and analyzed by SEM at standard magnification of ×1000. The presence/absence of the smear layer as well as the presence/absence of open tubules at the coronal, middle, and apical third of each canal were estimated using a five-step scale for scores. Numeric data were analyzed using Kruskal–Wallis and Mann–Whitney U statistical tests and significance was predetermined at P < 0.05.Results:Kruskal–Wallis analysis of variance (ANOVA) for debris score showed significant differences among the Ni-Ti systems (P < 0.05). Mann–Whitney test confirmed that Group A presented significantly higher score values than other Ni-Ti systems. The same results were assessed considering the smear layer scores. ANOVA confirmed that the apical third of the canal maintained a higher quantity of debris and smear layer after preparation of all the samples.Discussion and Conclusions:Intra-canal heating of NaOCl at 180°C proved to be more effective in obtaining clean canal walls. On the other hand, extra-canal heating at 50°C of NaOCl left a higher quantity of debris and the smear layer was widely represented.