Objective: The aim was to compare restorative marginal integrity of ceramic crowns luted with bioactive and resin cements using micro-computed tomography (micro-CT) microleakage evaluations and bond strength assessment. Methods: Thirty molar teeth were prepared by sectioning and polishing for dentin exposure for resin cement build-ups. Teeth were randomly divided among three groups of cements: (1) bioactive (ACTIVA); (2) glass ionomer cement (GIC; Ketac Cem); and (3) resin luting agent (Nexus 3). Bonding regime and build-ups (4 mm × 2 mm) were performed using the recommended protocol. For microleakage assessment, 30 premolar teeth were prepared for dentin-bonded crowns using lithium disilicate ceramic and the computer-aided design and computer-aided manufacturing technique. Crowns were cemented with standard load, cement amount, and duration using three cements (Group A: bioactive; Group B: GIC; Group C: resin) and photopolymerized. Cemented crowns were evaluated for volumetric infiltration using micro-CT (Skyscan, Bruker 1173- at 86 kV, 93 µA, 620 ms) after immersion in 50% solution of silver nitrate (AgNO3) (24 hours). Shear bond strength (SBS) was assessed by fracture of cement build-ups at a cross-head speed of 0.5 mm/min in a universal testing machine. Results: Mean SBS among bioactive (21.54 ± 3.834 MPa) specimens was significantly higher than that for GIC (14.08 ± 3.25 MPa) specimens ( p < 0.01), but they were comparable to resin samples ( p > 0.05) (24.73 ± 4.32 MPa). Microleakage was significantly lower in crowns luted with bioactive (0.381 ± 0.134) cement compared to GIC (1.057 ± 0.399 mm3) ( p < 0.01) and resin (0.734 ± 0.166 mm3) ( p = 0.014) cemented crowns. The type of luting agent had a significant influence on the microleakage of crowns and bond strength to dentin ( p < 0.05). Conclusion: Bioactive cement exhibited less microleakage and comparable SBS to resin luting agents in in vitro conditions.

Objective: To investigate the failure loads of dentin bonded all-ceramic crowns when luted with Bioactive, resin and glass ionomer cements (GIC) in an in-vitro setting. Methods: This study was conducted at King Saud University, Saudi Arabia, from Nov.2018 to March 2019. In this study, 60 premolar teeth were prepared for dentin-bonded ceramic crowns. Lithium disilicate ceramic crowns fabricated using CAD-CAM technique were cemented to teeth using Bioactive (ACITVA), Resin (Nexus 3 Gen) and GIC (Ketac Cem- Maxicap). Half of the bonded specimens in each group were thermocycled (50000 cycles), however the remaining half were not aged (n=10). Fracture loads of bonded crowns were assessed by exposing them to static axial occlusal loads (1mm/min) using a round ended metal probe in a Universal testing machine. Means and standard deviations among the study groups were compared with ANOVA and Tukey-Kramer multiple comparisons test. Results: Highest failure loads were observed in resin group without ageing (thermocycling) (689.13±89.41 N), however, the lowest loads were observed in GIC specimens with ageing (243.16±49.03 N). Among non-aged samples, failure loads for Bioactive (480.30±47.26 N) group were less than Resin (689.13±89.41 N) samples but higher than GIC (307.51±45.29 N) specimens respectively. Among the aged specimens, Bioactive (404.42±60.43 N) showed significantly higher failure loads than GIC (243.16±49.03 N), however lower failure loads than Resin (582.33±95.95 N) samples. Conclusions: Dentin boned crowns with resin cementation showed higher failure loads than Bioactive and GIC luted crowns. Crowns luted with Bioactive cement showed acceptable failure loads for use as restoration on anterior teeth. doi: https://doi.org/10.12669/pjms.36.3.1946 How to cite this:Vohra F, Altwaim M, Alshuwaier AS, Al-Deeb M, Alfawaz Y, Alrabiah M, et al. Influence of Bioactive, Resin and Glass Ionomer luting cements on the fracture loads of dentin bonded ceramic crowns. Pak J Med Sci. 2020;36(3):---------.  doi: https://doi.org/10.12669/pjms.36.3.1946 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The aim was to evaluate the effect of ceramic lumineers on inflammatory periodontal parameters, gingival crevicular fluid (GCF) flow rate and cytokine profile. Patients were provided with lumineers using standardized technique including minimal to no preparation. Ceramic lumineers were etched with hydrofluoric acid and teeth with phosphoric acid followed by adhesive cementation. Periodontal parameters (Plaque index (PI), bleeding on probing (BOP), periodontal pocket depth (PPD), and clinical attachment loss (CAL)) were recorded at baseline and after 4, 12, and 24 weeks of lumineer cementation. Assessment of GCF flow rate and levels of IL-6 and TNF-α was made using enzyme linked immunosorbent assay (ELISA). The statistical significance was determined by the t-test, analysis of variance and post hoc Tukey’s test. It was found that PI, BOP, PPD, and CAL at baseline and 24 weeks were comparable (p > 0.05). The GCF volume at baseline was comparable to the GCF at week 24 (p > 0.05). The IL-6 levels at baseline (5.4 ± 3.6) were similar to those at 24 week (7.4 ± 5.2) (p > 0.05). The TNF-α at week 4 (65.3 ± 16.2), 12 (25 ± 10.2), and 24 (21.3 ± 7.6) was higher than the baseline (13.7 ± 5.8) (p < 0.05). Clinical periodontal parameters and GCF volume among patients treated with ceramic lumineers at baseline and twenty-four week follow-up were comparable. The GCF TNF-α levels significantly increased after ceramic lumineer cementation at 24-week follow-up.

The mandibular anterior lingual depression is an uncommon anatomical variant. It is difficult to be detected in conventional 2D plain radiographs representing a diagnostic challenge. In this report, we describe a patient who presented to the dental clinic for the extraction of impacted third molars. Upon cone beam computed tomography (CBCT) examination of the mandible, it was incidentally noted that he had bilateral anterior lingual depressions in his mandible. The presence of anterior lingual depressions is uncommon and to be found bilateral is rare. This bone topography represents a challenge for the oral surgeon during implant placement with an increased risk of complications. The incidental finding was documented in the patient's dental record for future implications in case an implant placement was needed.