Search

Objectives: This laboratory study evaluated the effect of three polishing systems on the surface roughness and gloss of resin composites., Materials and Methods: Thirty specimens (6 mm Ø × 8 mm) were fabricated from each of three resin composites: Z 350 XT (nanofill), Harmonize (nanohybrid), and Estelite Omega (supranonofill). All specimens were photopolymerized using a multi-peak LED curing unit (VALO-Standard mode), having a exitance irradiance of approximately 1000 mW/cm 2 against a polyester strip (PS). 2 mm was then removed from the irradiated end (finished) using #320 abrasive paper (F). Specimens were then randomly polished (P) using a one-step (1S) (OneGloss), two-step (2S) (EVE Diacomp Twist Basic CA), or 3-step (3S) (Astropol P) system (n = 10). For PS, F, and P groups, surface roughness (Ra) was measured using a surface roughness tester, and surface gloss was measured with a glossmeter. For each specimen, the percent recovery to the PS value (%R) of surface roughness and surface gloss were calculated. Data were analyzed using two-way ANOVA, followed by Tukey's test. Surface roughness and gloss values were submitted to Pearson's correlation test (α = 0.05). All statistical testing was performed using a pre-set alpha of 0.05., Results: The interaction term [resin composite × polishing system] was significant for both surface roughness (p = 0.001) and gloss (p = 0.0001). For all resin composites, the 2S and 3S systems provided a higher %R of surface roughness and gloss compared to those of the 1S system. There was a negative correlation between surface roughness and gloss, but only a few combinations showed strong correlations., Conclusions: The 2S and 3S polishing systems provided surfaces having greater smoothness and gloss compared to the 1S system. The ability to recover surface roughness and gloss was dependent on type of resin composite filler classification., Clinical Significance: The 3S and 2S polishing systems were more effective in achieving PS values than was the 1S system for all tested resin composites. However, individual polishing systems performed differently depending on type of resin composite., (© 2023 Wiley Periodicals LLC.)

The study investigated the ability of bioactive materials used to restore enamel and dentine specimens to prevent caries. Enamel (n = 50) and dentine (n = 50) specimens were obtained from bovine incisors, prepared, and randomly allocated to one of five groups according to the restorative treatment: alkasite without adhesive system; alkasite with adhesive system; high viscosity glass ionomer cement; resin composite; no restoration; negative control group. Specimens were restored, exposed to a thermal cycling aging protocol, sterilized, and exposed to a cariogenic challenge induced by Streptococcus mutans and then submitted to surface and subsurface microhardness tests and polarized light microscopy to verify the caries lesion development in enamel or dentine surrounding the restorative materials. Data were analyzed using one-way ANOVA. In enamel and dentine, glass ionomer cement, alkasite without and with adhesive system presented a lower percentage surface microhardness loss than resin composite and negative control. Enamel subsurface microhardness presented no statistically significant differences between glass ionomer cement, alkasite without and with adhesive system. Glass ionomer cement also did not present statistically significant differences from resin composite and the negative control. In dentine, glass ionomer cement showed the highest subsurface microhardness values. In conclusion, bioactive restorative materials provide greater protection to enamel and dentine against surface caries development than resin composite., (© 2023 Scandinavian Division of the International Association for Dental Research. Published by John Wiley & Sons Ltd.)

A systematic review and network meta-analysis was performed to provide evidence for the best polishing protocol for different types of resin composites to minimize surface roughness. A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, EMBASE, and Cochrane Library on July 2, 2019 (updated in December, 2020). In vitro studies that included at least two systems for polishing resin composites and analyzed surface roughness were included. The risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare surface roughness in resin composites with the different types of polishers. Surface under the cumulative ranking curve (SUCRA) analysis was performed to rank the probability for the best polishing system. After removal of duplicates, title and abstract screening yielded 34 studies. Network meta-analysis was not possible for hybrid and microhybrid composites. SUCRA analysis showed that abrasive paper discs allowed greater surface smoothness for nanohybrid and nanofill composites to a probability of between 83% and 91.6%. Silicon carbide brush had a 78.2% probability of being the best system for microfill composites. The use of abrasive paper disc polishers showed a favorable result in nanofill and nanohybrid resin composites. Silicon carbide brush has a greater chance of promoting a smoother surface for microfill resin composites., (© 2023 Scandinavian Division of the International Association for Dental Research. Published by John Wiley & Sons Ltd.)

Systematic review and network meta-analyses were performed to answer the question: Do intraradicular chemical pretreatments affect the bond strength of the adhesive interface between dentine and fiber post cements? A literature search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane Library in October 2018 (updated September 2021). In vitro studies that compared the bond strength assessed by push-out tests following at least two dentine chemical treatments prior to fiber post cementation were included. Risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare push-out bond strength of different chemical pretreatments. SUCRA (surface area under the cumulative ranking) analysis was performed to rank the pretreatments. After removing duplicates and screening titles and abstracts, 61 studies remained. SUCRA analysis showed that the best bond strength values for self-etch, etch-and-rinse, and self-adhesive cements were ethyl acetate (SUCRA: 99.8%), low concentration NaOCl (SUCRA: 83.4%), and grape seed extract (SUCRA: 97.6%), respectively. According to the SUCRA rankings, ethanol was in a good position for all adhesive strategies (SUCRA: 78.6%). The use of chemical pretreatments in intraradicular dentine of endodontically treated teeth depends on the adhesive and cementation strategy. The pretreatment generally associated with the highest bond strength was ethanol., (© 2022 Scandinavian Division of the International Association for Dental Research. Published by John Wiley & Sons Ltd.)

Objective: The purpose of this randomized clinical trial was to evaluate the influence of glass fiber posts on fracture susceptibility of endodontically treated maxillary anterior teeth with direct veneers., Materials and Methods: Fifty participants had 1 maxillary anterior tooth restored with a direct veneer. They were divided into 2 groups (n = 25) according to the use of intraradicular glass fiber posts. Clinical evaluation was performed at baseline, 6 and 12 months. The treatment success was determined by the absence of tooth fracture. If there was fracture, it was classified according to its extent. Fischer exact test was performed to analyze the criteria among the groups at each evaluation time. Friedman repeated analysis of variance assessed the difference in the performance of each group at three recall times (α = 0.5)., Results: For control group, at the 6-month follow-up, one tooth had suffered a catastrophic failure, which resulted in tooth extraction. Fisher statistical analysis showed no significant difference between the cumulative success rate of the groups for the 6 (P > .999) and the 12-month (P > .999) period. Friedman test showed no significant difference among the periods of evaluation (P > .999)., Conclusions: Both groups had a similar success rate for maxillary anterior endodontically treated teeth with direct veneers after 12 months., Clinical Implications: Glass fiber post use does not influence the fracture susceptibility of maxillary anterior endodontically treated teeth with direct veneers in the short term., (© 2020 Wiley Periodicals LLC.)

The transcription factor RUNX1, a pivotal regulator of HSCs and haematopoiesis, is a frequent target of chromosomal translocations, point mutations or altered gene/protein dosage. These modifications lead or contribute to the development of myelodysplasia, leukaemia or platelet disorders. A better understanding of how regulatory elements contribute to fine-tune the RUNX1 expression in haematopoietic tissues could improve our knowledge of the mechanisms responsible for normal haematopoiesis and malignancy insurgence. The cohesin RAD21 was reported to be a regulator of RUNX1 expression in the human myeloid HL60 cell line and during primitive haematopoiesis in zebrafish. In our study, we demonstrate that another cohesin, NIPBL, exerts positive regulation of RUNX1 in three different contexts in which RUNX1 displays important functions: in megakaryocytes derived from healthy donors, in bone marrow samples obtained from adult patients with acute myeloid leukaemia and during zebrafish haematopoiesis. In this model, we demonstrate that alterations in the zebrafish orthologue nipblb reduce runx1 expression with consequent defects in its erythroid and myeloid targets such as gata1a and spi1b in an opposite way to rad21. Thus, also in the absence of RUNX1 translocation or mutations, additional factors such as defects in the expression of NIPBL might induce haematological diseases., (© 2020 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Objective: The purpose of this clinical report was to describe the detection of fluorescent resin residue after orthodontic bracket debonding with two UV light devices and analyze the surface morphology of enamel after 1 year., Clinical Considerations: A 22-year-old woman had orthodontic brackets removed by a previous dentist; however, resin residue was left on the enamel of the maxillary teeth. After confirming the fluorescent property of the resin, different protocols were used for each half of the maxillary arch. The first method, a black light lens was attached to a light-curing device to detect resin fluorescence, followed by polishing with silicone rubber tips. The second method used a light emitting diode light system attached to and activated by a high-speed handpiece, followed by polishing with discs. Both methods were completed with diamond polishing paste applied with felt discs. Polyvinyl siloxane impressions were made initially, after residue removal, after finishing and after polishing for morphologic analysis. The results were evaluated with photographs and the scanning electron microscope images made of resin casts from the impressions. A follow-up was made after 1 year., Conclusions: Both methods yielded a satisfactory clinical outcome, with a smooth surface, acceptable surface gloss and minimal tooth wear. The use of a UV device that excites fluorescence is recommended for the controlled removal of resin residue on enamel., Clinical Significance: The controlled removal of resin residue from enamel after orthodontic treatment is challenging but can be improved with auxiliary methods for detecting resin residues. This clinical report describes two types of devices that excite fluorescent resins in a more rapid and precise technique to guide the practitioner in the controlled removal of residual resin on teeth., (© 2018 Wiley Periodicals, Inc.)

Background: Gingival recession (GR) is frequently associated with non-carious cervical lesion (NCCL) forming a combined defect (CD). The aim of this study was to evaluate a new multidisciplinary protocol for CDs., Methods: Forty patients presenting 40 Miller's Class I or II GR defects associated with B+ tooth cervical defect were randomly allocated to one of the following treatments: test group (n = 20), partial restoration (PR) of the NCCL, in which the apical border of the restoration was placed 1 mm beyond the cement-enamel junction estimation, and connective tissue graft (CTG + PR) and Control Group (n = 20), odontoplasty of the NCCL and connective tissue graft (CTG). Clinical, aesthetic and patient-centred outcomes were evaluated., Results: After 12 months, CD coverage rates were 75.3% (2.5 ± 1.0 mm) for CTG + PR and 74.6% (2.4 ± 1.1 mm) for CTG (p > 0.05). The estimated complete root coverage was 60% (n = 12) for CTG + PR and 70% (n = 14) for CTG. CTG + PR resulted in significantly better dentin hypersensitivity (DH) reduction (p = 0.034). Both groups resulted in aesthetic improvements; however, the CTG + PR group showed better gingival contour results., Conclusions: CTG and CTG + PR were effective to treat CD. Use of PR resulted in better gingival margin contour and DH reduction, without effect on CD coverage by CTG. (NCT02817763)., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: To evaluate clinically, the aesthetics and the patient-centred parameters after the treatment of gingival recession associated with non-carious cervical lesion by connective tissue graft alone or combined with a nanofilled resin composite restoration., Methods: Thirty-six patients presenting one Miller Class I or II gingival recessions and B+ tooth cervical defect were included. The defects were treated by either connective tissue graft (CTG: control group; n = 18) or connective tissue graft plus resin composite restoration (CTG+RC: test group; n = 18)., Results: The mean percentage of defect coverage was 82.16 ± 16.1% for CTG and 73.84 ± 19.2% for CTG+RC after 1 year (p > 0.05). Both groups presented statistically significant improvements in two aesthetics evaluations. The professional evaluation (MRES) was 7.44 ± 2.3 for the CTG group and 7.52 ± 2.27 for CTG+RC after 1 year, with no significant difference between the groups. The two groups presented significant reduction of dentin sensitivity (DS), it decreased from 94.4% of the sites to 44.4% in the CTG group and from 88.8% to 5.5% in the CTG+RC group., Conclusions: CTG or CTG+RC can successfully treat gingival recession associated with B+ non-carious cervical lesion, but less sensitivity may be expected with the combined approach (NCT02423473)., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)