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This study evaluated the impact of different repair protocols on a composite resin substrate using distinct bonding agents submitted or not to artificial aging. Unopened sets of a single-step universal adhesive system (UA) and silane-coupling agents, a single-step pre-hydrolyzed (PH) or a two-step immediately hydrolyzed (IH), were used. Half of the sets were subjected to artificial aging being stored at 48 °C for 30 days, while the other half remained unaged. The composite resin substrates were prepared and aged in distilled water, sandblasted (Al 2 O 3 ), and cleaned. Then the different repair protocols were applied according to the groups. UA was used without a previous silane layer, while PH and IH were applied followed by a single-step etch-and-rinse adhesive system. Adhesive systems were light-activated, and four composite resin cylinders were formed over the substrate. After 24 h, the specimens were subjected to microshear bond strength (μSBS) test and failure mode analysis. The μSBS data were subjected to two-way ANOVA followed by Tukey HSD; Kruskal-Wallis analysis was used for failure mode distribution (α = 0.05). After aging the products, UA showed higher bond strength, while PH had significantly lower results, and IH showed no significant differences (p = 0.157). No significant differences were found for bond strength among the repair protocols when using non-aged products (p > 0.05). The protocols using UA and IH showed no significant differences between aged and non-aged bottles, whereas PH exhibited lower bond strength when comparing aged and non-aged products. More cohesive failures were observed in the resin substrate for the IH group without aging., (© 2024. The Author(s), under exclusive licence to The Society of The Nippon Dental University.)

Dental anatomy education for dental technology students should be developed in alignment with digital dental laboratory practices. We hypothesized that a virtually assisted sketching-based dental anatomy teaching module could improve students' acquisition of skills essential for digital restoration design. The second-year dental technology curriculum included a novel virtual technology-assisted sketching-based module for dental anatomy education. Pre- and post-course assessments evaluated students' skill sets and knowledge bases. Computer-aided design (CAD) scores were analyzed after one year to assess how the skills students developed through this module impacted their subsequent CAD performance. Participants who undertook the dental sketching-based teaching module demonstrated significantly improved theoretical knowledge of dental anatomy, dental aesthetic perception, and spatial reasoning skills. A partial least squares structural equation model indicated that the positive effects of this module on subsequent CAD performance were indirectly mediated by dental aesthetic perception, spatial reasoning, and practice time. A virtually assisted sketching-based dental anatomy teaching module significantly improved students' acquisition of skills and knowledge and positively mediated dental technology students' CAD performance., (© 2024 American Association for Anatomy.)

Objectives: Children, especially the mentally disabled, are generally incapable of obtaining adequate oral hygiene levels by manual brushing due to their lack of knowledge about oral hygiene and their limited motor skills. In order to handle those limited skills, different designs of manual and electric toothbrushes are developed and put on markets. The aim of this study was to evaluate the effectiveness of pulsating toothbrushes with easy-to-use properties, against conventional toothbrushes and to analyze their benefits on mentally disabled pediatric patients., Methods: Thirty-one healthy and 31 mentally disabled children (aged between 7 and 12) participated in this study. The effectiveness of three different toothbrushes (Oral-B Pulsar, Colgate 360° Micro Sonic Power, Oral-B Stages 3) was investigated with a cross-over study design. DMFT, dft, modified sulcus bleeding index (MOD-SBI), approximal plaque index (API) and Green and Vermillion simplified oral hygiene index (G&V OHI-S) measurements are performed to evaluate the oral hygiene status., Results: In the mentally disabled group the manual toothbrush for MOD-SBI, and Colgate 360° Micro Sonic Power for API showed the best results respectively., Conclusion: The ability of tooth brushing was improved both in healthy and in disabled children during this 5 months study. Unfortunately, it was not obvious in disabled children. Persevering training for tooth brushing might be the most important regardless of the kind of toothbrush., (© 2024 Special Care Dentistry Association and Wiley Periodicals LLC.)

Purpose: This study evaluated the effect of an aromatic silane compound and acidic functional monomer on the bond strength of fused quartz. Materials and Methods: A total of 264 disk specimens were fabricated from fused quartz for shear bond testing. Two silane compounds were used: 3-(trimethoxysilyl)propyl methacrylate (3-TMSPMA) and 3-(4-methacryloyloxyphenyl)propyltrimethoxysilane (3-MPPTS). As acidic functional monomers, 4-methacryloyloxyethyl trimellitate (4-MET) and 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) were used. The disks were primed with one of each silane compound with or without the acidic functional monomer of the same molarity. The specimens were bonded with a tri-n-butylborane (TBB) initiated luting material. The shear bond strength was determined before and after 10,000 thermocycles. Bond strength was statistically evaluated with Kruskal-Wallis, Mann-Whitney U-, and Steel-Dwass tests. To test dye penetration, the specimens were immersed in 0.5 wt% fuchsin solution for 24 h after priming with each condition, bonding, and 10,000 thermocycles. The dye penetration area was determined by observing the backside of the bonded specimen with an optical microscope. The relationship between the shear bond strength and dye penetration ratio was analyzed with Spearman's rank correlation test. Results: The highest post-thermocycling bond strengths in the 1 mol% and 2 mol% groups were 3-TMSPMA + 10-MDP and 3-MPPTS + 10-MDP. Spearman's rank correlation coefficient between shear bond strength and dye penetration area was γ = -0.7519, indicating a strong negative correlation. Conclusion: The surface treatments of 3-TMSPMA and 3-MPPTS combined with 10-MDP yielded higher bond strength after 10,000 thermocycles than those combined with 4-MET, despite the similarity in molarity. The shear bond strength was negatively correlated with the dye penetration area. [ABSTRACT FROM AUTHOR]

Purpose: To systematically review the literature to determine whether silane combined with adhesive application improves the repair bond strength of direct methacrylate-based resin composites in comparison to the use of an adhesive alone. Materials and Methods: The literature up to December 2019 was searched through PubMed/MEDLINE, Scopus, and Lilacs databases with no publication year or language limits. From 676 potentially eligible studies, 81 were selected for full-text analysis, and 19 were included in the systematic review. Two reviewers independently selected the studies, extracted data, and assessed the risk of bias. Meta-analyses were conducted using a random effects model to calculate pooled mean differences between adhesive- vs silane-plus-adhesive surface treatments (global meta-analysis) and considering subgroup analyses (immediate and aged repair bond strengths and type of silane - hydrolyzed or nonhydrolyzed). Statistical analyses were performed using RevMan5.3 at a significance level of 5%. Results: Global meta-analysis showed that the use of silane prior to adhesive application produced significantly higher repair bond strengths (p=0.003). A higher mean difference (effect size: 7.30, 95% CI: 2.91-17.51) between groups was found when nonhydrolyzed silanes were used. The heterogeneity was high. Studies scored between medium and high risk of bias. Conclusion: An additional silane application step could increase the repair bond strength of methacrylate-based resin composites. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the roughness, surface energy, and the bond strength of lithium disilicate yielded by two different types of nonthermal plasma (NTP), oxygen- or argon-based, compared to the conventional method. Materials and Methods: Ninety-three lithium disilicate (IPS e.max Press) samples were divided into 3 groups: HF (hydrofluoric acid group); ONTP (oxygen-based NTP group); ANTP (argon-based NTP group). Surface energy and roughness analyses were performed before and after surface treatment, and bond strength testing was performed before and after 5000 thermocycles. Scanning electron microscopy (SEM) was used to characterize the surface treatments. Data were submitted to ANOVA and Bonferroni's test with statistical significance set at 5%. Results: The ONTP group presented the highest surface energy values, followed by ANTP and HF. In addition, the ONTP group had higher surface roughness. SEM revealed exposed lithium disilicate crystals in the HF group, but a homogeneous film coverage in both NTP groups. Regarding bond strength, ANTP presented statistically significantly higher values than the other groups before thermocycling, and statistically significantly lower values than the other groups after thermocycling. The HF and ONTP groups presented statistically similar values after thermocycling. Conclusion: The bond strength of resin cement to lithium disilicate obtained after oxygen-based NTP was comparable with that obtained after conventional hydrofluoric acid treatment. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the formed biofilm on two types of implant surfaces (hydrophilic or hydrophobic) associated with titanium (Ti) or zirconia (Zn) abutments. Materials and Methods: Samples were separated into four groups according to type of surface and abutment used (n = 10): (1) hydrophobic/Ti abutment, (2) hydrophilic/Ti abutment, (3) hydrophobic/Zn abutment, and (4) hydrophilic/Zn abutment. Implant-abutment assemblies were incubated with human saliva and supragingival biofilm. Samples of biofilm were evaluated by DNA Checkerboard hybridization, identifying up to 41 species. Scanning electron microscopy (SEM) images were obtained from the implants and abutments. Results: The microbial count was higher for samples from groups with the hydrophilic/Ti abutment, followed by hydrophobic/Zn abutment, hydrophilic/Ti abutment, and hydrophobic/Zn abutment (P < .05). Hydrophilic surfaces and Zn abutments showed the highest counts of microorganisms. Individual bacterial counts were variable between groups; the hydrophilic/Zn abutment group had the highest microbial diversity, including T forsythia, P nigrescens, S oralis, S sanguinis, L casei, M orale, P aeruginosa, P endodontalis, S aureus, S gallolyticus, S mutans, S parasanguinis, S pneumoniae, and C albicans. The hydrophilic/Ti abutment group had the highest count of T forsythia and T denticola, microorganisms of Socransky red complex. The SEM images showed the bacterial colonization in both surfaces of the implant and abutment. Conclusion: Different surfaces of implants and abutments showed significant differences in the count and diversity of species. The hydrophilic/Zn abutment group presented the highest count and diversity of target species. [ABSTRACT FROM AUTHOR]

Biomimetic materials are able to mimic the structure and functional properties of native tissues especially natural oral tissues. They have attracted growing attention for their potential to achieve configurable and functional reconstruction in oral medicine. Though tremendous progress has been made regarding biomimetic materials, significant challenges still remain in terms of controversy on the mechanism of tooth tissue regeneration, lack of options for manufacturing such materials and insufficiency of in vivo experimental tests in related fields. In this review, the biomimetic materials used in oral medicine are summarized systematically, including tooth defect, tooth loss, periodontal diseases and maxillofacial bone defect. Various theoretical foundations of biomimetic materials research are reviewed, introducing the current and pertinent results. The benefits and limitations of these materials are summed up at the same time. Finally, challenges and potential of this field are discussed. This review provides the framework and support for further research in addition to giving a generally novel and fundamental basis for the utilization of biomimetic materials in the future. [ABSTRACT FROM AUTHOR]

In-office bleaching, using hydrogen peroxide, is effective to remove dental enamel stains. However, bleaching agents can deteriorate surface properties of CAD-CAM materials. This in vitro study aimed to investigate the effect of in-office bleaching agents on Vickers hardness and surface topography of polished and unpolished dental CAD-CAM composite materials (Grandio blocs, Lava Ultimate, BRILLIANT Crios, Cerasmart), and a polymer-infiltrated ceramic network block (Vita Enamic). The specimens were randomly divided into two groups: unpolished or polished. The micro-hardness and surface topography of each group were measured before bleaching, after a 60 min bleaching period, and 24-h and one-month post-bleaching. In-office bleaching significantly influenced the Vickers hardness of both the polished and unpolished CAD/CAM composite blocks, with Vita Enamic exhibiting the least hardness stability among all groups. Furthermore, in-office bleaching significantly influenced the surface roughness of unpolished CAD/CAM composite blocks. There was a significant difference in hardness reduction between the polished and unpolished specimens for most of the investigated materials at different time points. The bleaching did not influence the surface roughness of the investigated polished group, except for Vita Enamic and Lava Ultimate. However, it did influence the surface roughness of the investigated materials in the unpolished group. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to investigate the relationships of oral health status and swallowing function with cognitive impairment in community-dwelling older adults from Changsha, Hunan Province, China. Methods: In this cross-sectional study, we analyzed the data of 215 participants aged ≥ 50 years which were retrieved from the Xiangya and Panasonic mild cognitive impairment (MCI) Study, a community-based study conducted among the residents of the urban areas of Hunan province in China. Demographic information of all participants was collected. We determined oral function by evaluating oral hygiene, oral dryness, occlusal force, tongue pressure, chewing function, swallowing function, remaining teeth number, and other indicators. The mini-mental state examination (MMSE) was used to screen for cognitive function. The relationship between each oral function evaluation item and cognitive function was investigated using correlation analysis. The associations between oral health status and swallowing function with cognitive impairment were inferred using multiple regression analysis. Results: The general characteristics of participants showed statistically significant correlation coefficients in number of teeth remaining (p = 0.003) and number of teeth lost (p < 0.0001). Almost half of the 25 participants (48%) were aged from 70–80 years. Only 25 older adults (11.6% of the participants) were determined to have cognitive impairment by MMSE sores less than 24. Tongue pressure in male participants was the only significant independent variable that was associated with cognitive impairment (p = 0.01971). The results indicate that male participants with lower MMSE scores had a relative deficiency in tongue pressure. Conclusions: In this cross-sectional study, the oral health status and swallowing function of participants were in relatively good condition and showed low correlations with cognitive impairment. However, lower tongue pressures were associated with lower MMSE scores in males, indicating it could serve as a novel oral function index for evaluating cognitive impairment. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of zirconia priming with MDP-Salt before MDP containing primers and self-adhesive cement on the shear bond strength. Materials and methods: Fully sintered high translucent zirconia specimens (n = 120) were assigned into 2 groups (n = 60 each): Control (No Pretreatment) and Methacryloyloxydecyl dihydrogen phosphate salt (MDP-Salt) pretreated. Each group was divided into 3 subgroups (n = 20) according to cementation protocol: 1) MDP + Silane primer and conventional resin cement, 2) MDP+ Bisphenyl dimethacrylate (BPDM) primer and conventional resin cement, and 3) MDP containing self-adhesive resin cement. Shear bond strength (SBS) was measured after 10,000 thermocycling. Contact angle was measured for tested groups. Surface topography was assessed using a 3D confocal laser scanning microscope (CLSM). Weibull analysis was performed for SBS and one-way ANOVA for contact angle and surface topography measurements (α = 0.05). Results: The use of MDP-Salt significantly improved the SBS (p <.05) for all tested subgroups. Self-adhesive cement showed an insignificant difference with MDP + Silane group for both groups (p >.05). MDP + BPDM showed a significantly lower characteristic strength compared to self-adhesive resin cement when both were pretreated with MDP-Salt. No difference between all tested groups in the surface topographic measurements while MDP-Salt showed the highest contact angle. Conclusion: MDP-Salt pretreatment can improve bonding performance between zirconia and MDP containing products. [ABSTRACT FROM AUTHOR]

Due to the resistance of some bacteria to antibiotics, research in the field of dealing with bacterial infections is necessary. A practical approach utilized in this study involves the preparation of an antibacterial thin film on the surfaces, which can effectively inhibit and reduce biofilm formation and bacterial adherence. In this study, we report the fabrication of bactericidal titanium (Ti) and copper (Cu) surfaces which involves a powerful co-sputtering method. This method provides a situation in which constituent elements are deposited simultaneously to control the composition of the thin film. Prepared samples were examined by energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM), and contact angle measurements. To evaluate antibacterial behavior, we used two bacterial strains Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Antibacterial activity of the prepared sample was assessed by determining the number of colony-forming units per milliliter (CFU/ml) using a standard viable cell count assay. Results indicated that as the Cu concentration increased, the nanoscale surfaces became rougher, with roughness values rising from 11.85 to 49.65 nm, and the contact angle increased from 40 to 80 degrees, indicating a hydrophilic character. These factors play a significant role in the antibacterial properties of the surface. The Ti-Cu films displayed superior antibacterial ability, with a 99.9% reduction (equivalent to a 5-log reduction) in bacterial viability after 2 h compared to Ti alone against both bacterial strains. Field emission scanning electron microscopy (FE-SEM) images verified that both E. coli and S. aureus cells were physically deformed and damaged the bacterial cell ultrastructure was observed. These findings highlight that adding Cu to Ti can improve the antibacterial ability of the surface while inhibiting bacterial adherence. Therefore, the Ti14-Cu86 sample with the highest percentage of Cu had the best bactericidal rate. Investigation of toxicity of Cu-Ti thin films was conducted the using the MTT assay, which revealed their biocompatibility and absence of cytotoxicity, further confirming their potential as promising biomaterials for various applications. [ABSTRACT FROM AUTHOR]

There has been a systematic review of studies that used FEA in dental sciences, but no adequate risk of bias (RoB) analysis technique has been developed. Therefore, the development and validation process of RoB in studies using the finite element analysis in dentistry (ROBFEAD) tool is described. In the first phase of development, the scope of the tool and possible modifications were covered, and validation was done in the second phase. The developed tool comprised 6 domains and a total of 22 guiding questions in these domains. This article proposes the development and validation of ROBFEAD, a tool for measuring RoB in finite element research in dentistry. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate different surface treatments thought to increase the bond strength between zirconia ceramic and adhesive resin cement. Methods: The samples were prepared in 15 × 10 × 2 mm dimensions by cutting off monolithic zirconia ceramic blocks (Incoris TZI; Sirona, Germany). Surface roughness measurements were made with a profilometer, the average surface roughness (Ra1) was recorded, and five different surface treatments were applied. Group 1: Control group. No surface treatment was applied. Group 2: Sandblasted with Al2O3 under pressure of 50 μm. Group 3: Sandblasted with 30 μm Al2O3 - SiOx under pressure, then tribochemical silica coating, silane bonding agent, and ceramic primer were applied. Group 4: Samples were etched in a hot acid solution containing methanol, HCl, and chloride at 100 °C. Group 5: Samples were coated in a solution containing Grade C Aluminum Nitrite at 75 °C for 15 Sects. 12,000 thermal aging was carried out to all samples. Then, samples were bonded to a composite surface (Filtek Z250) with two different types of adhesive cement (Panavia F 2.0, Rely X U200) (n = 10). A load was applied to the samples attached to the Universal Test Device for the SBS, and the SBS was recorded. The surface roughness measurements of all samples were made again, and the average surface roughness Ra2 was recorded. The data was analyzed with a two-way ANOVA test. Bonferroni correction was used for multiple comparisons of the groups. p = 0.005 was accepted as the statistically significant value. Results: There was no statistically significant difference between the groups in the Ra1 measurements (p = 0.031). There was a statistically significant difference between the Ra2 values of Groups 4 and 5 and the Ra2 values of Groups 1,2 and 3 in the Ra2 measurements (p < 0.001). There was no statistically significant difference between the SBS values of the groups (p > 0.005). Also, there was no statistically significant difference in the SBS values of all groups for the two different cements tested (p > 0.005). Conclusions: None of the surface treatments applied to monolithic zirconia ceramic samples increased the SBS between ceramic and adhesive resin cement. [ABSTRACT FROM AUTHOR]

Objective: To study the influence of glazing on strength repair of lithium disilicate glass–ceramics after defect incorporation in different production processing phases. Materials and methods: Bar-shaped specimens (1 × 1 × 12 mm, n = 280; 20/group) made from different lithium disilicate ceramics (IPS e.max CAD, Ivoclar, "LD" or advanced lithium disilicate CEREC Tessera, Dentsply Sirona, "ALD") were exposed to 7 different protocols: crystallized without (c) and with glaze layer (cg), with a defect incorporated before crystallization without (ic) and with glaze layer (icg), with a defect after crystallization without (ci) or with glaze layer (cig), and defect incorporated after the glaze layer (cgi). The flexural strength was determined using the three-point bending test. Analysis of indented areas and fractured specimens was performed by scanning electron microscopy. Flexural strength data were evaluated by two-way ANOVA followed by Tukey tests (α = 5%). Results: Two-way ANOVA revealed a significant influence of ceramic (p < 0.001; F = 55.45), protocol (p < 0.001; F = 56.94), and the interaction protocol*ceramic (p < 0.001; F = 13.86). Regardless of ceramics, defect incorporation as final step resulted in the worst strength, while defects introduced before crystallization did not reduce strength. Glaze firing after defect incorporation led to strength repair for ALD, whereas such an effect was not evident for LD. Conclusions: The advanced lithium disilicate must receive a glaze layer to achieve its highest strength. Defects incorporated in the pre-crystallized stage can be healed during crystallization. Defects should not be incorporated after glazing. Clinical relevance: Clinical adjustments should be performed on pre-crystallized or crystalized restorations that receive a glazer layer afterwards. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To compare the shear bond strength (SBS) of orthodontic brackets bonded to three different types of ceramic surfaces (feldspathic, lithium disilicate, and zirconium) using Assure® Plus All and Transbond™ XT adhesives. MATERIALS AND METHODS: The sample comprised 72 monolithic computer‑aided design and computer‑aided manufacturing (CAD/CAM) ceramic samples that were randomly divided into six groups of 12 specimens each. Three groups (G1, feldspathic ceramic; G3, lithium disilicate ceramic; G5, zirconium surfaces) were bonded to metal brackets using Assure® Plus All adhesive, whereas the remaining three groups (G2, G4, G6; with the ceramic type in the same order as that in the previous groups) were bonded to metal brackets using Transbond™ XT. The samples were then subjected to 10,000 thermocycles. The SBS was calculated using the shear tests. The site of bonding failure was classified using the adhesive remnant index (ARI) score. One‑way analysis of variance (ANOVA) and Kruskal–Wallis tests were used for statistical analyses at a 5% significance level. RESULTS: Statistically significant differences were observed in the mean SBS values of the groups (P < 0.001). The mean SBS for G6 (zirconium plus Transbond™ XT) (2.52 MPa) was significantly lower than that for all other groups. Furthermore, statistically significant differences were found in the ARI score distribution among the groups (P < 0.001). Differences were identified between G6 and G3 (lithium disilicate Plus All Assure® Plus All) and G5 (zirconium plus Assure® Plus All). CONCLUSIONS: The mean bonding strength of brackets with Assure® Plus All was higher than that with Transbond™ XT for all three types of ceramics. However, all groups, except the zirconium plus Transbond™ XT group, showed acceptable bonding strength for orthodontic purposes. The application of hydrofluoric acid followed by silane and finally the Assure® Plus All adhesive system is adequate for bonding brackets to any of the ceramic tested surfaces. [ABSTRACT FROM AUTHOR]

The aim of this in-vitro study was to investigate the tactile assessment ability at the implant impression-taking stage. Thirty clinicians (18 novices, 12 experts) were included for a tactile fit assessment by using a used/new probe (tip diameter 100 µm/20 µm). Six implant replicas and related impression copings of two internal connection implant systems were used, each with a perfect fit (0 µm) and defined vertical micro gaps of 8, 24, 55, 110 and 220 µm at the interface. Statistical analysis was performed using descriptive methods and non-parametric tests with a focus on specificity (ability to detect perfect fit), sensitivity (ability to detect misfit), and predictive values. P-values <5% were considered statistically significant. The tactile assessment showed a mean total sensitivity for the Straumann and Nobel Biocare systems of 83% and 80% with a used probe, and 91% and 92% with a new probe, respectively. The mean total specificities were 33% and 20% with a used probe and 17% and 3% with a new probe, respectively. No statistical significance was observed between novice and expert clinicians concerning their tactile assessment ability. The ability to detect a perfect fit (specificity) with a probe was very poor for both implant systems and impaired with the use of a new probe. The use of a new probe improved the gap detection ability (sensitivity) significantly at the expense of the specificity. A combination of additional chairside techniques with training and calibration could improve clinicians' ability to correctly assess the fit/misfit at the implant-abutment interface. [ABSTRACT FROM AUTHOR]

Aim: To investigate the optimum concentration of silane added in fiber-reinforced composites (FRCs) and its effect on flexural strength and surface hardness. Methods and Material: The degumming process was conducted by soaking the chopped Bombyx mori silkworm cocoons in Na2CO3 solution, hydrolyzing them with NaOH, and neutralizing them with hydrochloric acid. Then, lyophilization and ultra-sonification were carried out. Bombyx mori short-silk fibers (±1.49 µm) were placed into a silane solution with concentrations of 0%, 0.5%, 1%, and 1.5%. After silanation, fibers were mixed in a composite resin matrix. The volume fraction of the fiber used was 10%. Flexural strength and surface hardness tests employed 48 samples in beam and disc shapes, respectively. Each group included six samples. Flexural strength was tested using a universal testing machine and surface hardness using a microhardness tester in accordance with ISO 4049 (2000). Data obtained were analyzed statistically by analysis of variance (ANOVA), followed by a post hoc least significant difference test. Results: In the ANOVA test, a significant difference was found in the flexural strength and surface hardness among the four FRC groups (P < 0.05). In the post hoc test, the flexural strength of the FRC group with 0.5% silane was significantly different from other groups (P < 0.05). Meanwhile, the surface hardness of samples added with 0.5% silane was not significantly different from those added with 1% and 1.5% silane (P < 0.05). Conclusions: Thus, 0.5% silane might be the optimal concentration to obtain FRCs with appropriate flexural strength and surface hardness. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to describe the scientific literature on the use and applications of manual and electronic toothbrushes. Materials and Methods: An electronic search without date restriction was carried out in the PubMed and Scopus databases. The articles were selected, and their characteristics, objectives, and methods were analyzed using the following keywords: "manual toothbrush," "electronic toothbrush," "interdental brush," "dental plaque," "gingivitis," "periodontitis" and "mechanical cleaning." Ten relevant studies investigating the uses and applications of manual versus electronic toothbrushes were selected for this review. Results: The studies determined the efficacy of electronic and manual toothbrushes for the reduction of gingivitis and plaque, detailing the characteristics of the populations. Some studies evaluated the effectiveness of the two classes of brushes using different dental plaque indexes. One study determined plaque removal by comparing an interactive versus manual toothbrush, and two studies evaluated the effectiveness of the brushes in plaque reduction in a pediatric population. Based on the research articles, it was evident that some studies found no significant difference in biofilm removal in the use of electronic toothbrushes versus manual toothbrushes. Conclusion: In summary, it is not possible to give a conclusion because there is a discrepancy between the authors, and further studies are needed to corroborate and contrast the usefulness of manual and electronic toothbrushes. [ABSTRACT FROM AUTHOR]

Purpose: To compare and contrast mechanical properties of experimental alkali-resistant (AR) glass fibre-reinforced composites (FRCs) silanised with one of three functional trialkoxysilanes: 3-methacryloxypropyltrimethoxysilane (3-MPS), 8-methacryloxypropyltrimethoxysilane (8-MOS) and 3-acryloxypropyltrimethoxysilane (3-APS). The experimental AR-FRCs were silanised with or without plasma pretreatment. Materials and Methods: Continuous unidirectional AR-glass fibres (ARcoteX® 5326 2400tex, Owen Corning) were cleansed ultrasonically, treated either with or without cold plasma (Piezobrush® PZ2, Relyon Plasma, Germany), then silanised by immersion for 10 min in activated, hydrolysed silane solution containing either 3-MPS, 8-MOS or 3-APS. The fibre bundles were next air-dried (24 h), and dried in vacuum oven (80 °C, 5 kPa, 2 h), producing 6 types of silanised AR-glass fibres. Next, silanised AR-glass fibres were laminated with a resin matrix, bis-GMA:TEGDMA at 60:40 wt%, CQ at 0.7 wt%, DMAEMA at 0.7 wt% for 10 min and paired randomly in rovings of two in stainless steel moulds (2 mm × 2 mm × 25 mm) to prepare an AR-FRC beam specimen (n = 16). All specimens were light-cured from the top and bottom directions for 60 s (Elipar S10, 3 M ESPE). Half of the samples (n = 8) underwent accelerated artificial ageing by immersion in boiling water (100 °C, for 16 h). Finally, 12 experimental AR-FRC groups were produced. All specimens were subjected to the three-point bending test with the upper surface (facing curing light) towards the cross-head. After testing, fibres, silanised and non-silanised, were inspected under a scanning electron microscope (SU1510, Hitachi, Tokyo, Japan). Statistical analysis was performed with three-way ANOVA and the Tukey post hoc test at α = 0.05. Results: The flexural modulus, flexural strength, and fracture work of the materials were significantly affected by silane type (p < 0.05) and artificial ageing (p < 0.001). Plasma treatment on AR-glass fibres significantly reduces flexural modulus of FRCs (p < 0.001) and slows the plasticising effect of artificial ageing on FRCs. Conclusion: Long chain silanes impart higher flexural strength and lower flexural modulus to AR-FRCs. While artificial ageing halves flexural strength and plasticises them, plasma surface pre-treatment of AR-glass fibres before silanisation reduces the plasticising effect. [ABSTRACT FROM AUTHOR]

Background: Effective dental plaque removal is essential for oral health. Different toothbrush parameters including head-size, filament-diameter and interdent-height and different brushing movements like horizontal, rotating and vertical may affect plaque removal efficacy. The purpose of the study was to examine plaque removal efficacy of different design parameters of manual toothbrushes. Methods: Eight manual toothbrushes were tested using a validated robot test to examine efficacy of toothbrush on replicated human teeth. Characteristics tested were: (i) head-size, (ii) filament-diameter, (iii) cutting-height, (iv) hardness, (v) interdental-height. Each test ran five times in horizontal, rotating, vertical movements. Simulated Plaque removal was evaluated using automated plaque planimetry: 30 fields/tooth, 13 areas representing buccal, lingual, proximal tooth sites. The Kolmogorov-Smirnov-test was applied to test tooth surface variables for normal distribution of plaque removal values. Parameters were analysed by independent two-sample t-test to assess mean differences. Where null hypothesis of normality was rejected, the Wilcoxon-Mann-Whitney-U-test was used. Results: Plaque removal was significantly better with toothbrush having smaller head-size (compact vs. full-size); smaller filament-diameter (0.12 mm vs. 0.15 mm); larger cutting-height (12 mm vs. 9 mm); softer filaments (0.15 or 0.18 mm vs. 0.23 mm) and greater interdent-height difference (8.5/11 mm vs. 10/11 mm). Conclusions: Manual brushes allowing filaments free to flex with longer, softer and/or having a difference in filament length overall removed significantly more simulated plaque as compared to more standard flat trim, stiff brushes with shorter, harder bristles and a larger head size. While limited by the in vitro nature of the study design, this indicates that the advances in toothbrush design can further enhance plaque removal. [ABSTRACT FROM AUTHOR]

Objective: We aimed to introduce the concept of "Selective adhesive luting—SAL" which is explained through clinical steps and supported by preliminary laboratory evidence. Clinical Considerations: Cementation with rubber dam is difficult to perform in case of short abutment teeth and/or subgingival crown margins. By means of universal resin cements/universal adhesive systems, which can be employed in self‐adhesive as well as adhesive luting procedures, this paper presents a novel technique allowing clinicians to perform reliable cementation where rubber dam isolation is difficult. The SAL technique entails the application of a universal adhesive system only on easily accessible abutment surfaces, enabling simultaneous adhesive and self‐adhesive luting in different portions of the abutment. The SAL clinical workflow is explained through prosthodontic rehabilitation of maxillary right central incisor affected by microdontia and restored with a lithium‐disilicate crown. Furthermore, our laboratory microshear bond strength study supports the rationale behind SAL application demonstrating higher bond strength even when the adhesive resin is placed only on one portion of the cementation substrate. Clinical Significance: This article advocates the application of SAL technique in clinical situations where effective adhesive luting is uncertain, since it can improve the adhesion between the tooth and universal resin cements. [ABSTRACT FROM AUTHOR]

Copyright of Current Research in Dental Sciences is the property of Ataturk University Coordinatorship of Scientific Journals and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Identifying the prevalence of adenoid hypertrophy (AH) and craniofacial factors associated with this condition requires studies with random sampling from the general population, and multiple criteria can be used for assessing AH on lateral cephalometric radiograph (LCR). The present analysis represents the first report performed according to these requirements in a large cross-sectional sample of children. Methods: LCRs of 517 12-year-old children (286 males, 231 females) randomly selected from the general population were retrospectively retrieved. AH was defined using three criteria (At/Nd, Ad-Ba/PNS-Ba, 1-Npaa/Npa), and twelve craniofacial variables were measured (SNA, SNB, ANB, Wits, Cd-Gn, MnP^SN, MxP^MnP, TPFH/TAFH, OPT^SN, C2ps-C4pi^SN, H-CV, H-FH). Skeletal characteristics were compared between children with and without AH using Mann–Whitney U test. Binary logistic regression (adjusted for sex and skeletal growth) was used to independently quantify the association between craniofacial factors and AH. Results: The prevalence of children with AH was 17.6% (according to At/Nd), 19.0% (according to Ad-Ba/PNS-Ba), and 13.9% (according to 1-Npaa/Npa). Children with AH presented greater antero-posterior jaw discrepancy (larger ANB, smaller SNB), greater mandibular divergence (larger MnP^SN), forward head posture (larger OPT^SN and C2ps-C4pi^SN), and anteriorly positioned hyoid bone (larger H-CV). Larger SNA (OR = 1.39–1.48), while smaller SNB (OR = 0.77–0.88) and Wits (OR = 0.85–0.87), were associated with greater likelihood of having AH, independently from the assessment method used. Conclusions: The prevalence of children with AH ranged from 13.9 to 19.0% based on LCR. Greater antero-posterior maxillo–mandibular discrepancy and mandibular retrusion were independently associated with higher likelihood of having AH. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effects of cusp inclination of the prosthetic preparation's occlusal surface and type of restorative material on the fatigue behavior, failure mode, and stress distribution of occlusal veneers. Materials and methods: Glass fiber–reinforced epoxy resin prosthetic preparations for occlusal veneers with three different occlusal surface cusp inclination degrees (0°, 15°, and 30°) were produced and assigned into six testing groups (n = 11) according to the cusp inclination (0°, 15°, or 30°) and type of restorative material (lithium disilicate—LD or resin composite—RC). Despite different substrate preparation cusp inclination degrees, the restorations were designed maintaining 30° inclination between the cusps at the occlusal surface and a thickness of 0.7 mm at the central groove region of the restorations to be machined in a CAD/CAM system. After cementation, the specimens were stored for about 7 days (under water at 37 °C), and subsequently submitted to a load to failure test (n = 2) and an intermittent cyclic fatigue test (n = 9) (initial load: 100 N; step size: 50 N; cycles/step: 10,000; loading frequency: 20 Hz; loading piston: 6-mm-diameter stainless steel) until observing cracks. The data were analyzed by two-way ANOVA, Kaplan–Meier, and Mantel-Cox post hoc tests. Finite element analysis (FEA) and fractographic analyses were performed. Results: The fatigue performance of LD and RC occlusal veneers was evaluated based on different prosthetic preparation cusp inclinations. The 0° inclination showed the best fatigue performance for both materials (LD: 944N, RC: 861N), while the 15° and 30° inclinations had lower values (LD: 800N and 533N, RC: 739N and 717N, respectively). The study also found that for a 0° inclination, LD occlusal veneers performed better than RC ones (LD: 944 N > RC: 861N), while for a 30° inclination, RC occlusal veneers had better fatigue performance than LD ones (LD: 533N < RC: 717N). No significant difference was observed between the materials for a 15° inclination (LD: 800N = RC: 739N). The FEA results showed a higher tensile stress concentration on lithium disilicate than on resin composite occlusal veneers. All lithium disilicate occlusal veneers showed radial crack failures, while resin composite occlusal veneers showed Hertzian cone cracks and radial cracks combined. Conclusion: Considering mechanical perspective only, RC occlusal veneers should be indicated when prosthetic preparation cusps inclinations are 30°. When 0° prosthetic preparation cusps inclinations are observed, LD occlusal veneers will behave mechanically better. When a 15° cusp inclination is preserved, both restorative materials behave similarly. [ABSTRACT FROM AUTHOR]

Biofilm cells have a different physiology than planktonic cells, which has been the focus of most research. Biofilms are complex biostructures that form on any surface that comes into contact with water on a regular basis. They are dynamic, structurally complex systems having characteristics of multicellular animals and multiple ecosystems. The three themes covered in this review are biofilm ecology, biofilm reactor technology and design, and biofilm modeling. Membrane-supported biofilm reactors, moving bed biofilm reactors, granular sludge, and integrated fixed-film activated sludge processes are all examples of biofilm reactors used for water treatment. Biofilm control and/or beneficial application in membrane processes are improving. Biofilm models have become critical tools for biofilm foundational research as well as biofilm reactor architecture and design. At the same time, the differences between biofilm modeling and biofilm reactor modeling methods are acknowledged. [ABSTRACT FROM AUTHOR]

Amorphous calcium phosphate (ACP) which is a transient phase in the natural bio -mineralization process has recently gained the spotlight. This study aimed to assess the effect of the incorporation of nano -ACP (NACP) in a dental adhesive with/without surface treatment with silane coupling agent on bond strength. NACP was synthesized by the wet chemical precipitation technique. To characterize the structure of NACP, X-ray diffraction, scanning electron microscopy, and energy -dispersive X-ray spectroscopy were used. Forty molars were randomized into 4 groups of 10. The teeth were restored with composite resin and the bonding agent (one of the four groups). Adper Single Bond 2 was used as the control group. In the 4 wt% NACP group, NACP fillers were added to the bonding agent. In 0.4 wt% and 4 wt% SNACP groups, silanized NACP fillers were added to the bonding agent. Finally, the mode of failure of specimens was determined. Data were analyzed by one -way ANOVA and Tukey's post -hoc tests. P< 0.05 was considered statistically significant. The addition of 4 wt% non -silanized NACP decreased the bond strength compared with the control group (P< 0.05). The bond strength of the groups with silanized fillers was not significantly different from that of the control group. The addition of silanized NACP to dental adhesive had no significant adverse effect on bond strength, which is a promising finding to pave the way for the synthesis of bonding agents containing bioactive fillers. [ABSTRACT FROM AUTHOR]

The presence of Si on the Ti surface is quintessential for a strong, durable silane‐based adhesion utilized in several dental applications. Silica‐coating and silanization form durable ≡Si‐O‐Si≡ bonds, which might have a positive effect on resin‐Ti adhesion. This laboratory study studied the effect of strong acids, their blends, and silica‐coating on Ti and resin‐Ti bonding. One‐hundred sixty‐eight c.p. grade 2 polished Ti samples (10 mm × 10 mm × 1 mm), out of which 96 were etched with 9% and 12%HF, a blend of 35%HCl+85%H3PO4 and a blend of 69%HNO3+35%HCl at 60°C, each for 2 min. One half was silica‐coated (Rocatec™ Plus, 110 μm SiO2‐coated‐Al2O3). Sixty Ti samples were first silica‐coated, and then, 48 of them were etched with 9%HF, 12%HF, a blend of 35%HCl+85%H3PO4, and a blend of 69%HNO3+35%HCl at 60°C for 2 min. SEM, EDX, XPS, and Ra analyses were carried out. Polished Ti samples were controls. All silanizations were carried out with a blend of 0.3 vol% 1,2‐bis‐(triethoxysilyl)ethane+1.0 vol% 3‐acryloxypropyltrimethoxysilane. Multilink™ Automix self‐adhesive resin composite cement was used in adhesion testing, and the samples were artificially aged followed by enclosed‐mold micro‐shear test on day 1 and weeks 1, 4, and 8. Failure mode analysis and statistical analysis with one‐way/two‐way ANOVA (p < 0.05) were carried out. HF etching produced the highest surface roughness. XPS analysis identified after etching with HF a variety of Ti and Si ions: Ti4+, Ti3+, Ti2+, and Ti0 and, on the other hand, Si4+, Si3+, and Si2+. A gradual decrease in adhesion strength was observed after artificial aging. Adhesive and cohesive failures were observed. [ABSTRACT FROM AUTHOR]

This study investigated the influence of silver diamine fluoride (SDF) on the shear bond strength (SBS) to artificial carious dentin and GIC restorations with various SDF application protocols. Artificial caries were prepared on human dentin discs using bacteria model. These samples were randomly allocated to five groups (n = 10/group) according to the following treatment: (1) control group (CD): no treatment (2) CSR: dentin conditioner, SDF, and rinsing (3) CS: dentin conditioner and SDF (4) SRC: SDF, rinsing and dentin conditioner, and (5) SC: SDF and dentin conditioner. The treated-dentin surface was bonded with GIC and subjected to SBS test. Mean SBS was analyzed using one-way ANOVA. Surface morphology and elemental contents after surface treatment were examined (n = 3/group) by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX). There was no significant difference in the mean SBS among CD (2.45 ± 0.99 MPa), CSR (1.76 ± 0.65 MPa), and SRC (2.64 ± 0.95 MPa). Meanwhile, the mean SBS of CS (0.35 ± 0.21 MPa) was significantly lower than the control and SRC group. SEM/EDX demonstrated deeper silver penetration in CSR and CS groups when compared to SRC and SC groups. SDF-modified GIC restorations resulted in significantly lower bond strength in CS and SC groups. The findings suggested treating the carious dentin surface with CSR and SRC protocol. SDF-treated carious dentin should be rinsed off prior to restore with GIC. [ABSTRACT FROM AUTHOR]

Conventional surface roughening treatments used for silica-based ceramics in order to improve subsequent adhesion become unreliable for zirconia ceramics. Laser conditioning can be a good alternative. The purpose of this in vitro study was to compare conventional (macro) shear bond strength (SBS) values obtained between resin composite and zirconium oxide ceramic samples grouped according to different micromechanical treatments received, and examine differences in surface roughness. One-hundred and fifty disks of sintered zirconia were randomly divided into 5 groups and roughened as follows: (1) Group NOT, no surface treatment; (2) Group APA, abraded with 50-μm aluminum-oxide (Al2O3) particles; (3) Group TBS, abraded with 30-μm aluminum-oxide particles covered with silica; (4) Group CO2, irradiated with a CO2 laser which emitted in continuous wave mode at 3 W of power; and (5) Group FEM, irradiated with a pulsed femtosecond laser, with an incident energy of 10 μJ, a frequency of 1000 Hz, and a fluence of 1.3 kJ/cm2. All surfaces were treated with a MDP-containing adhesive/silane coupling agent mixture upon which were prepared and light polymerized composite resin cylinders. Shear bond strength was measured and samples were observed by scanning electron microscopy (SEM). Statistically significant differences (p < 0.05) were found among all groups, except between CO2 and FEM, which showed the highest adhesion values (15.12 ± 2.35 MPa and 16.03 ± 2.73 MPa). SEM revealed differences in surface patterns. CO2 laser irradiation can be an alternative to sandblasting, although it could also weaken the ceramic. Suitable surface patterns on zirconia ceramics can be obtained with ultrashort pulsed radiation emitted by a pulsed femtosecond laser. [ABSTRACT FROM AUTHOR]

Purpose: To investigate mechanical properties of experimental resin composites containing 8-methacryloxyoctyltrimethoxysilane (MOS) and a more commonly used silane monomer, 3-methacryloxypropyltrimethoxysilane (MPS). Materials and methods: MOS and MPS were hydrolysed in 95vol% ethanol solution at pH 4 for 1 h before silanisation of SiO2-based bioactive glass powder fillers (Ø1.0 μm, Schott, Germany) at 3, 6, 9 and 12wt% of silane. After drying in a vacuum oven (80 °C, 5 kPa, 2 h) they were mixed with a monomer mixture of urethane dimethacrylate and triethylene glycol dimethacrylate in a 70:30 weight ratio, camphoroquinone 0.7wt% and 2-(dimethylamino)ethyl methacrylate 0.7wt% to produce eight experimental groups of resin composites with a filler load of 72.7wt%. After photo-polymerisation for 25 min and post-curing at room temperature (24 h), uniform rectangular beams were cut out for the three-point bending test (2 mm×2 mm×25 mm, n = 8). The surface Vickers microhardness (VH) test (press-load 2.94 N for 10s, n = 6) was performed before observation under 3-D optical microscopy. Statistical analysis was performed using ANOVA followed by the Tukey post hoc test (p < 0.05). Results: ANOVA revealed that both the silane type and concentration significantly affected flexural modulus (p < 0.001), flexural strength (p = 0.001) and microhardness (p < 0.001). Resin composites containing MOS exhibited lower flexural modulus but higher strength at a lower concentration than MPS. MOS resin composites exhibited lower surface microhardness than MPS with the corresponding silane content. Conclusion: 8-Methacryloxyoctyltrimethoxysilane may confer different mechanical properties in resin composites compared to 3-methacryloxypropyltrimethoxysilane at the same concentration. Surface microhardness is reduced with 8-methacryloxyoctyltrimethoxysilane. [ABSTRACT FROM AUTHOR]

Introduction: This study was performed to evaluate the effects of varying brushing times on the dental plaque‐removal efficacy of a power toothbrush to determine the optimal length of time required to brush the teeth. Methods: A typodont with 32 teeth was divided into four quadrants and further divided into four zones each (two teeth per zone). Using a robotic arm, toothbrushing was performed over eight different brushing times (0, 60, 120, 180, 240, 300, 360, and 420 s) to remove the artificial plaque applied on the labial surface of the teeth in occlusion. Photographs were taken every 60 s from each zone of the typodont. The images obtained were processed using ImageJ software to measure the percentage of remaining plaque. Data were analysed with factorial ANOVA, least squares regression analysis, and post hoc Tukey tests. Results: Plaque removal significantly increased with brushing time across the brushing intervals studied (p < 0.05). Efficient plaque removal was achieved after 240 s of brushing. There was no significant difference in plaque accumulations between the maxillary and mandibular arch (p = 0.19) and the right and left areas after each time interval (p = 0.49). Conclusion: Brushing duration is negatively correlated with the remaining plaque for a given toothbrush. Two minutes of brushing is not sufficient for significant plaque removal. Considering the limitations of this in vitro study, clinical studies are needed in order to change brushing recommendations to 240 s. [ABSTRACT FROM AUTHOR]

Purpose: This in vitro study compared the accuracy between conventional and different intraoral scanner impression methods and stereophotogrammetry term of 3D deviation for a complete mandibular edentulous arch with 5 placed implants. Materials and methods: An edentulous mandibular model was prepared with three straight and two 17° angled screw‐retained abutments screwed on implants. Different impression techniques were compared: one conventional impression, CO (open‐tray splint impression coping, Polyether), three groups of intraoral scanners, TS (Trios 4), IT (iTero Element 2), and PS (Primescan), and one stereophotogrammetry, PIC (Precise Implants Capture). An extraoral scanner (E4 scanner) was used to digitize the reference model as a control group. Scan body positions were compared with 3D deviation by using a 3D analysis software program (Geomagic ControlX 2020.1.1) with the best‐fit alignment technique. The accuracy of the scan bodies' position of each impression technique between each group area was analyzed using one‐way ANOVA followed by Scheffé's comparison test for trueness and precision. (α = 0.05). Results: Statistical 3D deviations of the whole scan body were found among the CO, TS, PS, IT, and PIC groups for both trueness (p < 0.05) and precision (p < 0.05). PIC showed the least 3D deviation of trueness (48.74 ± 1.80 µm) and precision (5.46 ± 1.10 µm), followed by TS, PS, IT, and CO. CO had the highest 3D deviation of trueness (141 ± 5.58 µm) and precision (40.4 ± 1.3.39 µm), which was significantly different from PIC, TS, and PS. Conclusions: For completed‐arch digital implant impressions, stereophotogrammetry has shown better accuracy than other digital and conventional impression techniques, especially in terms of precision. The highest 3D deviation was found in the conventional splint open‐tray impression technique. [ABSTRACT FROM AUTHOR]

Objectives: White spot lesions (WSL) are prevalent in patients using orthodontic appliances. The presence of ion‐releasing compounds in the tooth‐appliance interface may limit enamel demineralization to control WSL incidence. Thus, this study aims to evaluate the mineral formation on SiNb‐containing experimental orthodontic resins and the influence of these fillers on the physicochemical and biological properties of developed materials. Materials and Methods: The SiNb particles were synthesized via the sol–gel route and characterized by their molecular structure and morphology. Photopolymerizable orthodontic resins were produced with a 75 wt% Bis‐GMA/25 wt% TEGDMA and 10 wt%, 20 wt%, or 30 wt% addition of SiNb. A control group was formulated without SiNb. These resins were tested for their degree of conversion, softening in solvent, cytotoxicity in fibroblasts, flexural strength, shear bond strength (SBS), and mineral deposition. Results: The addition of 10 wt% of SiNb did not impair the conversion of monomers, cytotoxicity, and flexural strength. All groups with SiNb addition presented similar softening in solvent. The presence of these particles did not affect the bond strength between metallic brackets and enamel, with SBS values ranging from 16.41 to 18.66 MPa. The mineral deposition was observed for all groups. Conclusion: The use of niobium silicate as filler particles in resins may be a strategy for the adhesion of orthodontic appliances. The 10 wt% SiNb concentration resulted in a material with suitable physicochemical and biological properties while maintaining the bond strength to tooth enamel and promoting mineral deposition. [ABSTRACT FROM AUTHOR]

Wire electric discharge machining (WEDM) is an important non-traditional manufacturing technique for industries processing hard-to-machine materials. It can produce complex shapes with high dimensional accuracy and surface finish. Ti6Al4V is frequently used in biomedical applications such as surgical implants, dentistry, and orthopedic wires. All these applications require machining complex profiles with high accuracy in terms of dimensions and surface properties. Multi-pass machining is a proven technique for minimizing the damage on the machined surface but increasing the number of passes lowers the productivity. Hence, careful selection of wire offset value for trim cutting is crucial to maintain process efficiency and keep the number of passes minimum. The objective of this study is to investigate the effect of wire offset in multi-pass machining on surface integrity, dimensional accuracy, and cutting speed in complex WEDM of Ti6Al4V and limit the number of trim passes to one. In addition, effect of electrode composition on machining responses is studied for three different types of wires (uncoated brass, Broncocut-W, and Topas Plus X). Experimental results indicate that a single trim cut at an offset value of 0.11mmprovides better surface finish and minimum recast layer. Surface roughness of 1.31 µm is obtained using brass wire: 16.5% and 18.6% less than for Broncocut-W and Topas plus X, respectively. Similarly, recast layer of 8.183 µm attained by brass wire is smaller than 8.98 µm, and 10.041 µm produced by the other wires. The uncoated brass wire has proved to be the best electrode for surface finish, recast layer thickness, and dimensional accuracy of the machined profile. However, Bronococut-W wire has performed better in terms of cutting speed. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Computerized Dentistry is the property of Quintessence Publishing Company Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this study was to perform an integrative review on the effects of cranberry and grape seed extracts concerning the disinfection of root canals maintaining the strength of the remnant tooth tissues' structure. A bibliographical search was carried out on the PubMed electronic platform using the following key terms: cranberry, grape seed, vaccinium macrocarpon, proanthocyanidin, antibacterial, antimicrobial, decontamination, disinfection, bacteria removal, bacteria eradication, bacteria elimination, endodontic, root canal, faecalis, and strength. The inclusion criteria involved articles published in the English language, until March, 2022, reporting the antibacterial effect of grape seed and cranberry extracts. Of 185 studies identified, 13 studies were selected for the present review. The grape seed extract (GSE), composed of proanthocyanidins, showed an antioxidant activity against the main bacteria found in endodontic secondary infection. The percentage of bacteria removal was recorded at around 96.97% by using GSE. Studies on cranberry extracts, which are composed of proanthocyanidins, revealed antimicrobial effects against bacteria related to periodontitis and dental caries. Additionally, GSE or cranberry allowed the dentin collagen cross-linking that preserved the 3D collagen network leading to the maintenance of the strength of the remnant tooth structure. However, the contaminated smear layer could not be removed by using only GSE or cranberry. Cranberry extracts and GSE revealed a significant antimicrobial activity in endodontic disinfection without changing the mechanical properties of the remnant dentin tissues. Furthermore, those components can be associated with traditional compounds to enhance their antimicrobial effects and eliminate the smear layer. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to investigate the effects of glazing technique and firing on the surface roughness and flexural strength of an advanced lithium disilicate (ALD) and lithium disilicate (LD). Methods: Eight groups of bar-shaped specimens (1 mm × 1 mm × 12 mm, N=160, 20/group) were manufactured from ALD (CEREC Tessera, Dentsply Sirona) and LD (IPS e.max CAD, Ivoclar). The specimens were then submitted to various posttreatments: crystallization (c), crystallization followed by a second firing (c-r), crystallization with glaze in one step (cg), and crystallization followed by a glaze layer firing (c-g). Surface roughness was measured by means of a profilometer, and flexural strength was determined using a three-point bending test. Surface morphology, fractography, and crack healing analysis were conducted using scanning electron microscopy. Results: Refiring (c-r) did not affect the surface roughness (Ra) while applying glaze at both cg and c-g procedures increased the roughness. ALDc-g (442.3 ± 92.5 MPa) promoted higher strength than ALDcg (282.1 ± 64.4 MPa), whereas LDcg (402.9 ± 78.4 MPa) was stronger than LDc-g (255.5 ± 68.7 MPa). Refiring completely closed the crack in ALD, but it had a limited effect on LD. Conclusions: Two-step crystallization and glazing improved ALD strength compared to the one-step protocol. Refiring and one-step glazing do not increase LD's strength, while two-step glazing has a negative effect. Clinical relevance: Besides both materials being lithium-disilicate glass ceramics, the glazing technique and firing protocol affected their roughness and flexural strength differently. A two-step crystallization and glazing should be the first choice for ALD, while for LD, glazing is optional and when necessary, should be applied in one-step. [ABSTRACT FROM AUTHOR]

Copyright of RSBO: Revista Sul-Brasileira de Odontologia is the property of UNIVILLE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The species of the Candida genus are opportunistic pathogenic fungi found in humans and are responsible for ∼80% of worldwide fungal infections. Aimed at diminishing and preventing Candida adhesion to cells or implanted devices in the human host, a large diversity of materials has been developed and functionalized that have attracted much interest. Furthermore, these materials have been focused almost exclusively on Candida albicans , followed by C. glabrata, C. parapsilosis , and C. tropicalis. Although an important diversity of materials has been synthesized to prevent adherence and formation of biofilms by Candida species, it is however important to evaluate the capacity of each material in terms of its property to diminish the adherence of Candida. These materials are discussed in this review. [ABSTRACT FROM AUTHOR]

Context: It is a challenge to bond resin materials with polyetherketoneketone (PEKK). To increase the bond strength, surface treatments using chemical adhesion, mechanical adhesion, or a combination of both can be used. Aims: The objective of the present study was to evaluate and compare the shear bond strength of PEKK to the composite resin after various surface treatments and to evaluate the fracture mode analyses. Materials and Methods: One hundred and twenty PEKK specimens were randomly divided into four groups (n = 30) after three different surface treatments (95% sulfuric acid etching, airborne abrasion with 110 μm aluminum-oxide, and 99% acetone). With the help of polytetrafluorethylene tube, resin composite (3M ESPE) was bonded on all the specimens, thermocycled, and subjected to shear bond strength testing. Thereafter, 15 samples from each group were assessed for fracture mode analyses using a scanning electron microscope. Statistical Analysis Used: Mean, Standard deviation, one-way analysis of variance (ANOVA) f-test, post hoc Tukey's test. Results: Statistical analysis using one-way ANOVA f-test revealed that the results were significant with a P < 0.05 with the maximum value obtained in the case of air abraded group and the minimum value obtained in the case of the untreated group. Adhesive failure mode was the most common among the air-abraded group. Conclusions: The mechanical surface treatment group (air abrasion) showed higher shear bond strength than the chemical surface treatment groups (sulfuric acid and acetone). The mixed-type fracture mode was most commonly noted in the air-abraded group. [ABSTRACT FROM AUTHOR]

Purpose: To assess and compare the impact of various computers aided design/manufacturing (CAD/CAM) materials on internal and marginal discrepancies, fracture resistance and failure probability of Endocrown restorations with 3D Finite Element analysis. Material and methods: Forty devitalized human maxillary first molars were collected. After endodontic treatment, they classified into 4 groups (n = 10) based on the materials used for endocrown fabrication. Group V (Vita-Enamic), Group N (Nacera Hybrid), Group T (Translucent Prettau Zirconia) and Group P (Pekkton ivory). All samples were exposed to artificial aging method simulating one year of clinical service. Silicone replica technique and stereomicroscope (25X) utilized to evaluate the marginal and internal gaps of endocrowns at different areas. Fracture resistance test used for cemented specimens followed by qualitative investigation utilizing Stereomicroscopy. Four models representing four endocrown systems used for restoration of severely-damaged endodontically treated upper first molar were generated for finite element analysis (FEA). Axially and centrally static occlusal compressive load was applied. Modified Von Mises and maximum principal stress values on the remaining tooth structure, cement lines and restorative materials were assessed independently. Resulted data were statistically analyzed at P-value ≤ 0.05. Results: In the current study, the highest mean values of internal and marginal discrepancies (μm) among studied groups were reported for Zirconia group (100.300 and 102.650) respectively, while the lowest mean value of internal discrepancy (μm) was observed for Nacera group (69.275) and the lowest mean value of marginal discrepancy (μm) was observed for PEKK group (78.4750). Regarding internal discrepancy, Vita-Enamic and PEKK groups did not exhibit any statistically significant differences (P = 0.293), however zirconia and the other tested groups exhibited statistically significant differences in the mean values of the marginal gap region (p 0.05).On the other hand, PEKK group showed the highest mean value of fracture resistance (1845.20 N) and the lowest value was observed for Vita-Enamic group (946.50 N). Regarding to stress distributions through 3D FEA, and according to modified von Mises (mvM) analysis, the greatest possible stress values were noticed in PEKK model in relation to tooth structure, cement line, and flowable composite as the following: (93.1, 64.5, 58.4 MPa) respectively, while Zirconia revealed lower maximum stress values (11.4, 13.6, 11.6 MPa) respectively. Conclusions: Statistically excellent marginal and internal fit was observed for PEKK in relation to other used endocrown materials. Also, PEKK material explained fracture resistance comparable to zirconia value while the lowest value was detected for Vita Enamic material. [ABSTRACT FROM AUTHOR]

Background: Resin composite restorations are highly esthetic restorations, which should have and maintain high surface polish. However, esthetic restorations are subjected to different beverages at variable temperatures, which may affect their surface roughness. This study aimed to evaluate the surface roughness of single-shade (Omnichroma) and multi-shade (Filtek Z350XT) composite materials, following aging by immersion and thermocycling in different beverages, simulating one year of clinical service. Methods: Thirty specimens of each material were prepared and divided into 6 subgroups (n = 5). In each material, the grouping of the specimens was as follows: the first subgroup was the as-prepared specimens stored dry without immersion or thermocycling. The second, third, and fourth subgroups were immersed in saliva, tea, and red wine, respectively, for 12 days at 37 °C. The fifth and sixth subgroups were thermocycled for 10,000 cycles, in tea (the fifth between 37 and 57 °C) and in red wine (the sixth between 37 °C and12°C). The resultant surface roughness was measured by two different methods, stylus profilometer and atomic force microscopy (AFM). Intergroup comparison was performed using independent t test, while intragroup comparison was performed using one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test. Results: Intergroup comparison between both composites showed no statistically significant differences in all groups using the stylus profilometer roughness measurements (P>0.05), while the AFM measurements showed significant difference (P ≤ 0.05) within all storage media except the as-prepared control (P = 0.0645), where nanofilled Filtek Z350 XT showed lower nano-roughness. Intragroup comparison data were variable, depending on the material, aging conditions, and roughness assessment tool. However, the resultant average surface roughness (Ra) values in all groups did not exceed the threshold value of Ra 0.2 μm. Conclusions: Both resin composites attained and retained a clinically acceptable surface finish after immersion and thermocycling in different beverages. [ABSTRACT FROM AUTHOR]

Purpose: To assess the accuracy of fit of prosthesis prototypes fabricated via a complete digital workflow protocol with a reverse scan body skipping intraoral scanning for implant data acquisition. Materials and methods: A maxillary stone cast with four multiunit abutment implant analogs (Screw‐Retained Abutments, Institut Straumann AG, Basel, Switzerland) with adequate anteroposterior spread simulated a common clinical patient situation. This stone cast served as the master cast and an interim screw‐retained prosthesis was fabricated on it. Novel reverse scan bodies were connected to the interim prosthesis, and extraoral scanning was performed with a white light intraoral scanner. The produced standard tessellation language (STL) files were then imported to computer‐assisted design software and after the digital design, the STL file was exported to a computer‐assisted machining milling machine and a three‐dimensional (3D) printer to produce a total of 50 milled and 50 printed fixed complete denture prototypes, respectively. Two clinicians assessed the accuracy of fit of each digitally fabricated prosthesis prototype on the master cast, utilizing the screw‐resistance test and radiographic evaluation. Out of the 100 prototypes, 94% (94/100) were fitting accurately. Fisher's exact test was used to test the difference among the groups. The test revealed statistically significant results (p = 0.027). Results: Out of the 50 digitally fabricated milled prosthesis prototypes, 50 (100%) presented with accurate fit under in vitro assessment. Out of the 50 digitally fabricated 3D printed prototypes, 44 (88%) presented with accurate fit under in vitro assessment. Conclusions: Accurately fitting digitally fabricated prosthesis prototypes can be milled after extraoral scanning with reverse scan bodies without intraoral implant data acquisition. [ABSTRACT FROM AUTHOR]

In this study, single lap shear experiments with Al2024-T3 substrates were used to evaluate poly(dicyclopentadiene) (pDCPD) for structural adhesive applications. A wide range of monomer-to-catalyst ratios (M:C = 10,000:1 to 90,000:1) and four different silane coupling agents (i.e. hexyl, hexenyl, allyl, and norbornyl trimethoxysilane) were used to understand their effects on the adhesive shear properties of pDCPD. The roles of pDCPD oxidation and the bulk polymer on adhesive properties were also investigated using paint and dynamic mechanical analysis (DMA) measurements. Collectively, the data show that the choice of silane has a significant influence on the lap shear strengths of pDCPD, while the M:C ratio has a smaller but significant influence. Differences in bulk polymer topology as measured by DMA and oxidation of the resin had insignificant effects in the absence of exposed oxygen-rich surfaces that influence catalyst activity. With shear strengths up to 21.6 ± 0.7 MPa for dry conditions and up to 13.0 ± 0.7 MPa for hot-wet conditions (i.e. submersion in deionized water at 60 °C for 2 weeks), we showed that pDCPD-based adhesives have comparable lap shear properties to a well-studied model thermoset epoxy (i.e. DGBA/D230). [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of sterilization, conditioning method, and thermal aging on the retentive strength of two-piece zirconia abutments., Materials and Methods: In total, 128 stock zirconia abutments were divided into four groups (n = 32) according to the conditioning parameters: (A) air-abrasion using 50 μm alumina particles/1.0 bar, (B) 50 μm/2.0 bar, (C) 100 μm/1.0 bar, and (D) 100 μm/2.0 bar. All abutments were bonded onto titanium bases using DTK adhesive resin and stored in water bath (37°C) for 72 h. Each group was subdivided into two subgroups (n = 16), group 1 was disinfected, whereas group 2 followed disinfection and autoclave sterilization. Half of the specimens of each subgroup (n&#x02009;=&#x02009;8) was directly subjected to the axial retention test (groups N), while the other half was first subjected to 150&#x02009;days of thermocycling followed by retention test (groups T). Statistical analysis was performed with three-way ANOVA, additional statistical analysis was performed by using separate one-way ANOVAs followed by the Tukey's post-hoc test for post hoc pairwise comparisons among groups., Results: The highest median retention strength was recorded for group B2N (1390 N), whereas the lowest strength was recorded for group C1T (688 N). No significant interaction (p ≥ 0.05) was detected between the different variables; conditioning method, sterilization, and the thermal cycling regarding the effect on the resulting retention. However, the sterilization always showed a positive effect. Thermocycling presented an adversely significant effect only in the absence of sterilization (p < 0.05), with the exception of subgroups A. For the sterilized groups, thermocycling had no statistically significant effect on the retention., Conclusion: Steam autoclaving increased the retention of hybrid zirconia abutments. DTK adhesive resin for two-piece zirconia abutments performed well after sterilization and thermocycling., (© 2024 The Authors. Clinical Implant Dentistry and Related Research published by Wiley Periodicals LLC.)

Purpose: To evaluate the effect of mechanical, chemical, and mechanical-chemical surface treatment methods on shear bond strength between acrylic denture teeth and thermoplastic nylon denture base., Materials and Methods: Maxillary central incisor teeth were treated with five different surface treatment methods: mechanical (sandblasting, T-shape diatoric holes), chemical (5% acetic acid solution, bonding agent), and mechanical-chemical (sandblasting + bonding agent) were embedded in thermoplastic nylon denture base (n = 10). A universal testing machine with a crosshead speed of 0.5 mm per minute was used to test the shear bond strength. Data obtained were statistically evaluated using one-way ANOVA and followed with Tukey post hoc test (α = 0.05) RESULTS: T-shaped diatoric holes exhibited significantly higher shear bond strength among the surface treatment groups, followed by sandblasting + bonding agent, sandblasting, bonding agent, and the acetic acid group (p < 0.001) CONCLUSION: T-shaped diatoric holes as a mechanical surface treatment showed higher shear bond strength than other methods., (© 2024 by the American College of Prosthodontists.)