Search

Purpose: To evaluate the influence of enamel condition and etching strategy on bond strength of a universal adhesive in primary teeth. Materials and Methods: Thirty-six primary molars were randomly assigned to six groups (n = 6) according to the enamel condition (sound [S] and demineralized [DEM]/cariogenic challenge by pH cycling prior to restorative procedures) and adhesive system (Scotchbond Universal Adhesive [SBU]) used in either etch-and-rinse (ER) or selfetching (SE) mode, with Clearfil SE Bond as the self-etching control. The adhesives were applied to flat enamel surfaces and composite cylinders (0.72 mm²) were built up. After 24-h storage in water, specimens were subjected to the microshear test. Bond strength (MPa) data were analyzed using two-way ANOVA and Tukey's post-hoc tests (α = 0.05). Results: Significant differences were found considering the factors adhesive system (p = 0.003) and enamel condition (p = 0.001). Demineralized enamel negatively affected the bond strength, with μSBS values approximately 50% lower than those obtained for sound enamel. SBU performed better in etch-and-rinse mode, and the bond strength found for SBU applied in self-etching mode was similar to that of CSE. Conclusions: Enamel etching with phosphoric acid improves the bond strength of a universal adhesive system to primary enamel. Demineralized primary enamel results in lower bond strength. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the influence of selective enamel etching on long-term clinical performance of partial ceramic crowns (PCCs) luted with a self-adhesive luting material (RXU: RelyX Unicem). Materials and Methods: At baseline, 34 patients received the intended treatment: two PCCs (Vita Mark II; Cerec 3D) for the restoration of extended lesions with multiple-cusp coverage were placed in a split-mouth design with a self-adhesive luting material, one without (RXU) and one with selective enamel etching (RXU+E). Patients were evaluated clinically (modified USPHS criteria) at baseline and up to 6.5 years (70 to 88 months). The chi-square test was used for statistical analyses (α = 0.05). Clinical survival of all restorations (n = 68) after 6.5 years was evaluated by Kaplan-Meier analysis. Results: After 6.5 years, 18 patients (9 male, 9 female; median age 41, range 25 to 59 years) with 36 RXU and RXU+E restorations were available for clinical assessment (patient recall rate: 53%), with 13 RXU and 14 RXU+E PCCs placed in molars and 5 RXU and 4 RXU+E PCCs in premolars. Clinically, no statistically significant differences between the luting procedures were detected. Both RXU and RXU+E revealed significant changes over time with respect to marginal adaptation (significant deterioration) and marginal discoloration (significant increase). RXU revealed no cases of postoperative hypersensitivity and RXU+E only did so at baseline (n = 5). Kaplan-Meier analysis showed a cumulative survival for RXU of 60% and for RXU+E of 82%, indicating a significantly higher survival rate for RXU+E. Conclusion: Clinically, RXU and RXU+E perform similarly. In PCC restorations with multiple-cusp coverage, lack of retention due to adhesive preparation, and little dentin available for adhesion caused by extensive core buildups or cavity linings, selective enamel etching is recommended. [ABSTRACT FROM AUTHOR]

The aim of the present laboratory study was to three-dimensionally evaluate the interfacial adaptation of flowable materials with different flowability in a simulated deep-margin elevation scenario, before and after cyclic fatigue. The null hypothesis tested was that the substrate of the cervical margin, enamel or dentin, the material employed, and the simulated ageing did not influence the quality of the marginal sealing in terms of gap presence. 50 extracted premolars were selected, and two class II cavities were prepared: one mesial, with the cervical margin 1 mm above CEJ (enamel margin) and one distal, with the cervical margin 1 mm below CEJ (dentin margin). After performing adhesive procedures using a self-etch adhesive system with enamel selective etching, specimens were divided into 5 groups (n=10) according to the materials employed for horizontal margin relocation. G1: nanohybrid composite (Clearfil ES2,Kuraray); G2: medium viscosity flowable composite (Majesty ES2 Low-Flow, Kuraray); G3:low viscosity flowable composite (Majesty ES2 Superlow-Flow, Kuraray); G4: conventional viscosity flowable composite (Tetric Flow, Ivoclar); G5: CAD/CAM inlay (Katana Avencia, Kuraray). All restorations, except for G5 were finalized using an oblique layering with a nanohybrid composite. To reveal interfacial gap progression specimens were scanned with a micro-CT (SkyScan 1172), before and after 500000 cycles of thermomechanical chewing simulation (50 N, 1 Hz). Data were imported into Mimics software after smoothing and region growth: only the external gap of the relocation (2 mm) was considered in the analysis. Obtained STL optimal quality masks were imported into Geomagic software for noise removal and volume calculation. Interfacial gap progression, expressed in mm3, was collected and statistically analyzed with ANOVA test (α<0.05). The mean external gap augmentation was tri-dimensionally measured as volume. Three-way ANOVA showed significant differences in the data obtained for the variable substrate, material and ageing. Enamel performed better than dentin in all groups, ageing affected the gap presence over time and flowable materials reduced gap presence in comparison to nanohybrid composite. However, no differences were found between the different tested flowable composites. The initial null hypothesis was rejected since tested flowable resin composites, independently from their viscosity, showed less gap formation than nanohybrid composites at the enamel and dentin margin in deep second class. In addition, enamel guaranteed a better performance of the restorative materials both before and after ageing. Artificial ageing significantly affects the presence of volumetric gap at the interface. [ABSTRACT FROM AUTHOR]

To compare the clinical performance of universal adhesive with 3-step etch and rinse adhesive in non-carious cervical lesions (NCCLs). One hundred and forty-two restorations of Ninety-four patients participated in this study. This study divided patients into experimental A and experimental B, evaluating the performance of universal adhesives at baseline, 6-month recall, 1-year recall, and 2-year recall. In Experiment A, Single bond universal (SBU) was used as total etch technique and compared with Optibond FL (OFL) which is a three-step etch and rinse adhesive. In Experiment B, Tetric N-Bond universal (TBU)was used as self-etch with selective enamel etch technique and compared with OFL. FDI criteria were used as the evaluation criteria for the restoration. Statistical tests were performed using McNemar's test and Fisher's exact text (p = 0.05). At 2-year evaluation, in experiment A, 41 SBU restorations and 35 OFL restorations were recalled, and the cumulative retention rates were 88.4% of SBU and 76.7% of OFL. In experiment B, 35 TBU restoration and 30 OFL restoration were recalled, and the cumulative retention rate was 94.5% for TBU and 71.7% for OFL. There was no statistically significant difference in all evaluation criteria in experiment A. There was a statistically significant difference in fracture and retention at 2-year recall in experiment B. In experiment A, there were significant differences in OFL between baseline and 1-year recall, baseline and 2-year recall, 6-month recall and 1-year recall, and 6-month recall and 2-year recall. In experiment B, there were significant differences in OFL between baseline and 1-year recall, and baseline and 2-year recall. (p <0.05) In the 2-year follow up period, the universal adhesive SBU used with the etch-and-rinse strategy performed similarly to the 3-step etch-and-rinse adhesive OFL. In the 2-year follow up period, the universal adhesive TBU used with the self-etch strategy with selective etching performed better than the three-step etch-and-rinse adhesive OFL. [ABSTRACT FROM AUTHOR]

Objectives: Nd:YAG and Er:YAG lasers have been previously used as an adjunct in periodontal therapy. The aim of this single-blinded randomized controlled clinical trial was to evaluate the efficacy of a combined application of Nd:YAG and Er:YAG laser irradiation in periodontal treatment. Materials and methods: Twenty-two patients with at least one site of ≥ 6 mm periodontal probing depth (PPD) after mechanical debridement with curettes and sonic instruments at periodontal reevaluation were included in the study. Patients were randomly allocated at a 1:1 ratio to either a combined Nd:YAG/Er:YAG laser therapy (test group) or a "turned off" laser therapy (control group). The Nd:YAG laser was used for periodontal pocket deepithelialization and to stabilize the resulting blood clot. The Er:YAG laser was primarily used for root surface modification. PPD (mm), clinical attachment level (CAL, mm), and bleeding on probing (BOP, +/−) at the site of laser treatment were evaluated at baseline and 2 months after treatment. Results: The mean improvements from baseline to 2-month follow-up for PPD were significantly better in the laser group (2.05 ± 0.82 mm) compared to the control group (0.64 ± 0.90 mm; p = 0.001). Likewise, the gain in CAL was significantly better in the laser group (1.50 ± 1.10 mm) than in the control group (0.55 ± 1.01mm; p = 0.046). Conclusions: The combined application of Nd:YAG and Er:YAG laser irradiation as an adjunct to conventional non-surgical therapy showed a significant beneficial effect on periodontal treatment results. Clinical relevance: Combined Nd:YAG and Er:YAG laser irradiation could be a useful procedure additionally to conventional non-surgical periodontal therapy to improve periodontal treatment results. Clinical trial registration: ISRCTN registry #ISRCTN32132076 [ABSTRACT FROM AUTHOR]

Background: Tranexamic acid has been reported to benefit the treatment of postinflammatory hyperpigmentation (PIH). Laser-assisted drug delivery (LADD) could facilitate the efficacy of topically applied drugs into the dermis. This split-area randomized prospective study aims to assess whether early utilization of the LADD procedure with tranexamic acid delivery followed by picosecond lasers can attenuate the PIH better than the utilization of picosecond lasers alone. Patients and methods: Ten post-traumatic cases of PIH in 10 patients (8 female and 2 male) with an average age of 34.2 - 11.2 years were included in this clinical trial. Using block randomization to determine the treatment side, one side of each area of the PIH was separated from the midline into two halves belonging to the control and tranexamic acid groups. The half area of the tranexamic acid group was further topically applied with 10% tranexamic acid solution. This procedure was repeated every 6 weeks, four times in total. Results: The self-assessment of the hyperpigmentation and overall satisfaction of the treatment outcome were not significantly different between the treatment and control sides. Conclusions: This split-area study revealed that, compared with picosecond alone, there was no significant difference adopting tranexamic acid in LADD after nonablative fractional picosecond laser for PIH. [ABSTRACT FROM AUTHOR]

The most used product for surface acid conditioning for enamel is 37–40% phosphoric acid, which promotes greater mechanical retention. The objective of this study was to compare the shear bond strength (SBS) of brackets bonded to bovine enamel with different acid conditioning protocols and to analyze the surface morphology. 169 teeth (n = 13) were divided into 4 groups: control group without conditioning (G1), Dental Gel 37% phosphoric acid (Dentsply) (G2), Ultra Etch 35% (Ultradent) (G3) and Attaque gel 37% (Biodinâmica) (G4). Groups G2, G3 and G4 were subdivided according to the conditioning time into: 10 s (a), 15 s (b), 30 s (c) and 60 s (d). The superficial enamel morphology (n = 3) was analyzed using a scanning electron microscopy (SEM) to analyze the depth of the microporosities. The samples were submitted to the shear test (SBS) with the aid of a universal testing machine (INSTRON) with a speed of 1 mm/min. The enamel after debonding was analyzed to determine the adhesive remnant index (ARI) in a stereoscopic magnifying glass. The SBS data were analyzed using two-way ANOVA. ARI data were analyzed using generalized linear models and SEM measurements were analyzed using Kruskal Wallis and Dunn tests. The 95% significance level was used. The SBS within G2, G3 and G4 ranged from 11.11 to 12.66 MPa. ARI score 3 was observed in 35% of the samples. The samples analyzed in the SEM showed microporosity depth rangingfrom 1.28 to 2.48 μm. There was no difference between the acids and times evaluated for SBS. The ARI analysis showed that the studied acids provide protection to the enamel surface, keeping the adhesive attached to the buccal surface after debonding. The increase in conditioning time is directly proportional to the deterioration of the prismatic and interprismatic content. [ABSTRACT FROM AUTHOR]

Background: To evaluate the effect of Ethanol Wet Bonding Technique (EWBT) on postoperative hypersensitivity (POH) of composite restorations in premolar teeth. Materials and Methods: In this randomized trial, 24 patients with at least three proximal carious lesions with similar axial depth and position of gingival floor in their premolars were enrolled. Following cavity preparation, the teeth were randomly assigned to one of three groups: (1) Class II resin-based composite (RBC) restoration using an etch-and-rinse adhesive + wet bonding technique (Control); (2) RBC restoration using EWBT + hydrophobic adhesive; and (3) RBC restoration using EWBT + hydrophilic adhesive. Tooth hypersensitivity was evaluated before and 1, 3, 7, 14 and 30 days after treatment according to the Visual Analog Scale. Data were analyzed statistically with Kruskal-Wallis and Friedman tests (P = 0.05). Results: All teeth showed similar levels of hypersensitivity after treatment (both P > 0.05). Furthermore, there was no difference between POH levels of the test and control groups at any control period (P < 0.05). Friedman test indicated that the POH significantly reduced within time in all groups (P < 0.05). Conclusion: Application of ethanol-wet bonding technique, either with hydrophobic or hydrophilic adhesives did not affect the POH of Class II composite restorations in premolars. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the shear‐bond strength (SBS) of resin‐luting cement to experimental short fiber‐reinforced CAD/CAM composite (SFRC) compared to conventional CAD/CAM (Cerasmart 270), 3D printed (GC TEMP PRINT, Pro3dure GR‐17), and laboratory (Gradia Plus) composites. Moreover, translucency parameter values and light transmission were evaluated. For each of the five types of composites, discs were prepared (n = 16/group) and divided into subgroups (n = 8/group) according to surface treatment protocol (hydrofluoric acid or air‐particle abrasion). SBS test was performed using universal testing machine until failure, and failure modes were visually analyzed. Translucency parameter and curing‐light transmission values through 1, 2, and 3 mm thickness were quantified using spectrophotometry and the MARC resin calibrator, respectively. Scanning electron microscopy (SEM) was used to examine the CAD/CAM composites after surface treatment. Composite type and surface treatment had a significant effect on SBS. Laboratory composite showed the highest SBS value (22.4 MPa). Cerasmart 270 exhibited higher translucency parameter values (19.8, 11.0, 5.0) than SFRC (14.5, 5.2, 1.6) at the three composite thicknesses tested. Air‐particle abrasion was more effective in enhancing SBS than acid etching. Experimental SFRC CAD/CAM composite showed higher SBS values than Cerasmart 270. For all composites, translucency parameter values and light transmission decreased as thickness increased. [ABSTRACT FROM AUTHOR]

The success of the sandwich technique depends on the bond strength of composite to glass-ionomer cement (GIC)/resin-modified glass-ionomer cement (RMGIC). Currently used adhesives employ the total-etch and the self-etch techniques. The total-etch system is technique sensitive, whereas the self-etch system is popular for its ease of use. The aim of this systematic review is to compare the effect of total-etch and self-etch adhesives (SEAs) on the bond strength of composite to GIC/(RMGIC) in the sandwich technique. A literature search was conducted using electronic databases (PubMed, Web of Science, Ebscohost, and Scopus) limiting the year of publications from January 1, 2000, to September 30, 2018, to identify the relevant studies. All the cross-references of the selected studies were also screened. In vitro studies on extracted human teeth were selected. A total of 10 articles were included in this review. A conclusion was drawn that SEAs when used in the sandwich technique resulted in greater bond strength in comparison to total-etch adhesives. Moreover, increased bond strength was achieved when the primer was employed on unset GIC as compared to set GIC. Furthermore, the application of SEAs over uncured RMGIC (co-curing technique) resulted in better bond strengths as compared to their application over cured RMGIC. [ABSTRACT FROM AUTHOR]

• Pre-cementation procedures can affect both cement retention and crown strength. • Zirconia materials with different amounts of yttria-stabilizer benefit from different pre-cementation procedures. • Disc-shaped specimens are not suitable to assess all aspects of pre-treatment procedures for prosthetic restorations. Several pre-cementation procedures have been advocated to enhance adhesion between zirconia and resin-based cement. There is, however, limited documentation on how these pre-treatments affect the strength of zirconia crowns as most tests are performed on discs or bars. The aim was to assess the effect of pre-cementation procedures on fracture mode, fracture strength and cement retention on zirconia. Two dental zirconia materials with different yttria content were assessed (<4 and>5 mol%). Both discs (n = 45) and crown-shaped specimens (n = 30) of the two materials were pretreated with either air-abrasion or hot-etching with KHF 2 and compared with untreated controls with regards to surface roughness, crystallography, wettability, cement adhesion and fracture strength. Air-abrasion improves adhesion and strength of zirconia with moderate yttria content (<4 mol%). Acid etching with heated KHF 2 showed the best effect on strength and cement retention on zirconia with higher yttria content (>5 mol%). Application of KHF 2 was, however, complicated on crown-shaped specimens. Pre-treatment and cementation protocols should be optimized for different dental zirconias to improve both strength and retention. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Studies on the efficacy of erbium laser for enhancement of enamel resistance to acid attacks and its effects on fluoride uptake by the enamel are limited. Purpose: This study sought to assess and compare the effects of erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation and application of acidulated phosphate fluoride (APF) gel (alone and in combination) on remineralization of artificial white spot lesions (WSLs). Materials and Method: This in vitro, experimental study evaluated 90 buccal and lingual slabs of extracted human premolars. The specimens underwent pH cycling to induce WSLs. They were then randomly divided into 6 groups of caries-free positive control (c+), negative control with WSLs (ws), 1.23% APF gel applied on the enamel (F), Er:YAG laser irradiation (80 mJ, 10 Hz, and 8 J/cm² ) of enamel (L), APF gel application followed by laser irradiation (FL), and laser irradiation followed by fluoride gel application (LF). The fluoride ion content of specimens was measured before and after the intervention using a potentiometer. Data were analyzed by ANOVA (p< 0.05). Results: APF gel application before/after laser irradiation maximally increased the fluoride uptake by the enamel (p= 0.000). Application of APF gel in group F and laser irradiation in group L increased fluoride uptake by the enamel, compared with groups 1 and 2 (p= 0.000). Laser- treated (L) and APF-treated (F) groups had no significant difference in this respect (p= 0.945). Maximum fluoride concentration was noted in combined laser and fluoride groups (FL=332.07ppm and LF=341.27ppm) with no significant difference between the two (p= 1.000). Conclusion: Er:YAG laser irradiation changes the chemical composition of enamel and probably promote its remineralization, especially when combined with APF gel application, which highlights its cariostatic potential. [ABSTRACT FROM AUTHOR]

Dental resin composites are commonly used in the restorative management of teeth via adhesive bonding, which has evolved significantly over the past few decades. Although current self-etch bonding systems decrease the number of clinical steps, the acidic functional monomers employed exhibit a limited extent of demineralization of enamel in comparison to phosphoric acid etchants, and the resultant superficial ionic interactions are prone to hydrolysis. This study evaluates the etching of primers constituted with bis[2-(methacryloyloxy) ethyl] phosphate (BMEP) of dental hard tissue, interfacial characteristics, and inhibition of endogenous enzymes. We examine the incorporation of 2 concentrations of BMEP in the formulation of experimental primers used with a hydrophobic adhesive to constitute a 2-step self-etching bonding system and compare to a commercial 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP)-containing system. The interaction of the primer with enamel and dentine was characterized using scanning electron, confocal laser scanning, and Raman microscopy while the polymerization reaction between the BMEP primers and hydroxyapatite was evaluated by Fourier-transform infrared spectroscopy. The inhibitory effect against matrix metalloproteinase (MMP) enzymes of these primers was studied and percentage of inhibition analyzed using 1-way analysis of variance and Tukey's post hoc test (P < 0.05). Results of the scanning electron microscopy micrographs demonstrated potent etching of both enamel and dentine with the formation of longer resin tags with BMEP primers compared to the 10-MDP-based system. The BMEP polymerized on interaction with pure hydroxyapatite in the dark, while the 10-MDP primer exhibited the formation of salts. Furthermore, BMEP primers were able to inhibit MMP activity in a dose-dependent manner. BMEP could be used as a self-etching primer on enamel and dentine, and the high degree of polymerization in the presence of hydroxyapatite can contribute to an increased quality of the resin polymer network, prompting resistance to gelatinolytic and collagenolytic degradation. [ABSTRACT FROM AUTHOR]

The objective in this study was to enhance osteogenic responses (in vitro and in vivo) to roughened titanium (Ti) dental implants through the formation of superhydrophilic TiO2 nanonetwork surface structure. Sandblasting and acid etching (SLA) was used to roughen the Ti surface. An electrochemical anodization process was then used to form a superhydrophilic TiO2 nanonetwork on the SLA Ti surfaces. The pore size of the nanonetwork structure ranged from a few nanometers to more than 100 nm, which is on the same scale as many biological species. Human bone marrow mesenchymal stem cells were used as an in vitro test model. The TiO2 nanonetwork structure was shown to have a significantly positive effect on hydrophilicity, protein adsorption, cell adhesion, cell migration, cell mineralization, and the gene and protein expression of osteogenic markers. The osseointegration of an anodized SLA screw-type Ti dental implant was investigated in vivo via implantation in the femur of New Zealand white rabbits for durations of 4 or 12 wk. The presence of a superhydrophilic surface TiO2 nanonetwork was shown to significantly enhance the bone-to-implant contact of the roughened SLA screw-type Ti dental implants. Overall, the proposed superhydrophilic TiO2 nanonetwork structure on the roughened SLA Ti surface proved highly effective in enhancing osteogenic responses in vitro and in vivo. [ABSTRACT FROM AUTHOR]

In this study, the process of osseointegration on titanium implant surfaces with different physicochemical treatments subjected to a simulated corporal fluid submersion was evaluated using the concept of fractal dimension. It was found that different treatments led to rather different calcium phosphate crystal growth patterns, with fractal dimension ranging from 1.68 to 1.93. The observed crystal patterns may be explained by a general deposition, diffusion, and aggregation growth mechanism, where diffusing particle sticking probability plays a fundamental role. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the behavior of hard and soft tissue around implants with different surface treatments. Materials and Methods: Eight patients were identified for this study. Each patient received at least 2 implants (1 control, 1 test) into an edentulous quadrant, for a total of 10 pairs of implants. Two types of implants were used: hybrid implants (control) with a dual acid-etched surface in their apical portion and a machined coronal part, and test implants with an acid-etched surface throughout their entire length. Standardized periapical radiographs were taken at baseline, 3 months, 6 months, and 1 year post implant placement and then annually until the 6-year follow-up. Bleeding on probing (BOP) and Plaque Index (PI) were recorded annually. Probing depth (PD) was recorded at the 6-year follow-up. Results: Moderate crestal bone remodeling was observed during the 1-year post-implant placement evaluation (P = .001), and test implants revealed smaller marginal bone resorption (P = .030). No significant changes in bone level were observed between the 1-year and the 6-year follow-up appointments, and a significantly smaller bone resorption was found at test implants. No statistically significant differences in bone resorption were found between maxilla and mandible. No statistically significant differences were detected between test and control implants for BOP, PI, or PD. Conclusions: The preliminary results suggest that implant surface characteristics might affect the bone remodeling phase subsequent to the surgical trauma. However, once osseointegration was established, implant surfaces did not affect bone maintenance over time. Implant surfaces did not affect soft tissue behavior. The results of this pilot study need to be confirmed in a study with a larger sample size and over a longer time frame. [ABSTRACT FROM AUTHOR]

Purpose: Safe loading of dental implants requires an optimal osseointegration. This osseointegration process during healing could be analyzed by resonance frequency analysis (RFA). The purpose of the study was to evaluate RFA changes during healing in splinted, early-loaded, thermal acid-etched, hydrophilic implants over time. Materials and Methods: Patients received a minimum of two implants: an implant with the prosthetic abutment connection at the crestal bone level (bone level) and one with the prosthetic abutment connection at a 2.5-mm supracrestal site (tissue level). Implant stability was measured at weeks 0, 2, 3, and 12 using the Osstell device. Results: Seventy-six implants were placed in 32 patients. By week 2, early-loaded tissue-level implants showed a significant drop in mean ± standard deviation (SD) implant stability quotient (ISQ) values of 2.2 ± 3.6 (P < .001). Changes in ISQ values were significant between weeks 3 and 12 and also between weeks 0 and 12, with mean differences of 4.2 (P < .001) and 2.8 (P < .001), respectively. Early-loaded bonelevel implants show a significant change in ISQ of 2.3 ± 3.7 at week 2 (P < .01) and -1.3 ± 4.7 at week 12 when compared to an ISQ value of 2.9 ± 4.9 at week 3 (P < .01). Bone-level implants achieved higher ISQ values compared with tissue-level implants at weeks 0, 2, 3, and 12, with mean differences being 3.8 ± 5.5 (P < .01), 3.8 ± 6.1 (P < .01), 3.7 ± 6.7 (P < .01), and 2.3 ± 5.8 (P < .05), respectively. Conclusion: This study found a significant dip in ISQ values, with the lowest point seen at week 2. ISQ values remained higher in bone-level implants throughout the process of healing and osseointegration. [ABSTRACT FROM AUTHOR]

Purpose: To determine the influence of atmospheric pressure plasma (APP) treatment on the microtensile dentin bond strength of two self-etching adhesive systems after one year of water storage as well as observe the contact angle changes of dentin treated with plasma and the micromorphology of resin/dentin interfaces using SEM. Materials and Methods: For contact angle measurements, 6 human molars were sectioned to remove the occlusal enamel surface, embedded in PMMA resin, and ground to expose a flat dentin surface. Teeth were divided into two groups: 1) argon APP treatment for 30 s, and 2) blown air (control). For the microtensile test, 28 human third molars were used and prepared similarly to contact angle measurements. Teeth were randomly divided into 4 groups (n = 7) according to two self-etching adhesives and APP treatment (with/without). After making the composite resin buildup, teeth were sectioned perpendicular to the bonded interface to obtain beam specimens. The specimens were tested after 24 h and one year of water storage until failure. Bond strength data were analyzed by three-way ANOVA and Tukey's post-hoc test (a = 0.05%). Three beam specimens per group that were not used in the bond strength test were prepared for interfacial SEM analysis. Results: APP application decreased the contact angle, but increased the bond strength only for one adhesive tested. SEM evaluation found signs of degradation within interfacial structures following 1-year aging in water. APP increased the dentin surface energy, but the effects of APP and 1-year water storage on dentin bond strength were product dependent. Conclusion: APP increased the dentin surface energy. It also increased the bond strength for Scotchbond Universal, but storage for one year negated the positive effect of APP treatment. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the capability of chemicals to decontaminate Escherichia coli (E coli) or Porphyromonas gingivalis (P gingivalis) from sandblasted acid-etched (SAE) titanium dental implants. Materials and Methods: SAE titanium dental implants were contaminated with E coli or P gingivalis and incubated in a sterile bacterial culture media under aerobic and anaerobic conditions, respectively. The implants were treated with 10 different conditions: calcium hydroxide [Ca(OH)2] paste for 1 minute and saline irrigation for 1 minute; Ca(OH)2 paste for 1 minute and 0.2% chlorhexidine digluconate (CHXD) irrigation for 1 minute; 0.2% CHXD for 1 minute; Dakin's solution for 1 minute; tetracycline hydrochloride (T-HCl) as a 1 g per 20 mL solution for 1, 2, and 3 minutes; and T-HCl paste for 1, 2, and 3 minutes. All implants were irrigated with 1 mL of saline solution and incubated under aerobic and anaerobic conditions for 24 hours or 48 hours for E coli- and P gingivalis-contaminated implants, respectively. The control group was submitted to all procedures except for the chemical treatments. Aliquots were removed, and turbidity was measured by spectrophotometry. The level of bacterial growth in control cultures was considered to have a decontamination percentage (DC%) of 0. Results: Spectrophotometric analysis showed that all chemical treatments resulted in significantly higher DC% compared to controls for SAE implants contaminated with E coli (P < .05) or P gingivalis (P < .05). For the P gingivalis experiments, SAE implants treated with Ca(OH)2 paste and saline solution had a lower DC% (39.3%) than those in the other treatment groups. In the E coli experiments, DC% was significantly lower for SAE implants treated with Ca(OH)2 paste and saline solution (48.7%), Dakin's solution (92.7%), or T-HCl paste for 1 minute (96.6%) than those in the other groups. Conclusion: The DC% of SAE implants contaminated with E coli or P gingivalis by means of chemicals commonly used in dentistry is high, with the exception of Ca(OH)2 paste burnished for 1 minute and then irrigated with saline solution for 1 minute. [ABSTRACT FROM AUTHOR]

The article presents several abstracts on dental implants, including one by M. Esposito, M. G. Grusovin, H. Maghaireh et al. on dental implant loading, one by B. R. Chrcanovic, T. Albrektsson, and A. Wennerberg on functional loading and dental implant failure rates and one by F. Bassi, A. B. Carr, T. L. Chang et al. on the longevity of dental implants.

This study aimed to investigate the effects of (i) a high-irradiance (3s) light-curing protocol versus (ii) two standard-irradiance (10s) protocols on 2D temperature maps during intra-dental photo-irradiation within a molar cavity restored with either Ultra-Rapid Photo-Polymerized Bulk Fill (URPBF) composites or a pre-heated thermo-viscous bulk-fill composite, compared to a standard bulk-fill resin-based-composite (RBC). The specific objectives included visual assessment of the temperature maps and quantitative assessment of several temperature/time plots at four different locations. A caries-free lower first molar cavity served as a natural tooth mold. Resin composites were placed without intermediary adhesive. Two URPBF composites (PFill; PFlow) and one pre-heated thermo-viscous bulk-fill composite (Viscalor : VC) were compared to a contemporary bulk-fill composite (One Bulk Fill: OBF). Two LED-LCU devices were used: Bluephase PowerCure (PC) and Elipar S10 (S10), with three light-irradiation protocols (PC-3s, PC-10s and S10-10s). 2D temperature maps over the entire coronal area were recorded for 120 s during and after irradiation using a thermal imaging camera. Changes at four different levels were selected from the data sets: (0, 2 and 4 mm from the cavity top and at 1 mm below the dentin cavity floor). The maximum temperature attained (T max), the mean temperature rise (ΔT), the time (s) to reach maximum temperature and the integrated areas (°C s) under the temperature/time (T/t) plots were identified. Data were analysed via three-way ANOVA, One-way ANOVA, independent t-tests and Tukey post-hoc tests (p < 0.05). All RBCs showed qualitatively similar temperature-time profiles. PFlow reached T max in the shortest time. PC-3s (3000 mW/cm2) generated comparable ΔT to S10-10s, except with PFill, where ΔT was greater. Despite the same irradiance (1200 mW/cm2), Elipar S10 led to higher T max and ΔT compared to PC-10s. The highest T max and ΔT were observed at the 2 mm level, and the lowest were at 1 mm depth into the underlying dentin. Coronal 2D temperature maps showed rises largely confined within the bulk-fill RBC materials, with maxima at 2 mm rather than 4 mm depth indicating some extent of thermal insulation for the underlying dentin and pulp. RBCs polymerized via different irradiation protocols showed similar temperature changes. With the PC-3s protocol – also with pre-heated VC – minimal temperature rises at 1 mm within dentin suggest their clinical safety when sufficient remaining dentin thickness is present. [ABSTRACT FROM AUTHOR]

Objective: Different root modifiers have been proposed in the literature with an attempt to improve the healing process and the success rate of root coverage procedures. The aim of the present retrospective study was to evaluate the effect of three different types of root surface conditioning, namely, tetracycline (TTC), ethylene‐di‐amino‐tetra‐acetic acid (EDTA) and saline, on the outcome of root coverage procedures applying the same surgical technique. Materials and methods: Twenty‐nine patients with 60 Classes I, II, or III recession defects were treated using connective tissue with a partial‐thickness double‐pedicle graft. In 21 recession defects root surface was treated with TTC and, in other 21, with EDTA, while in the remaining, saline solution was applied. Statistical analysis consisted of descriptive statistics and Kruskal‐Wallis, Mann–Whitney, and chi‐square tests. Results: Differences between pre‐ and postoperative values were statistically significant only within but not between groups. Mean root coverage was 73.25%, 69.19%, and 82.17% in the TTC, the EDTA, and the saline groups, respectively. The study revealed no statistically significant differences for all evaluated parameters between groups. Conclusion: Within the limits of this study, root conditioning, prior to root coverage procedures, does not significantly affect their outcome. Clinical significance: Clinical outcome of root coverage procedures is not related to the type of root surface conditioning. [ABSTRACT FROM AUTHOR]

Background : Success of all-ceramic restorations depends on their cementation process. Bonding crystalline materials like zirconia to an underlying substrate is challenging. Recently, universal adhesives have been developed. They claim to chemically bond to zirconia due to the presence of compounds like 10-methacryloyloxydecyl dihydrogen phosphate. But for majority of these adhesives, few studies demonstrating their effectiveness are available. Aims : This study aimed to assess the effect of two universal adhesives, One Coat 7 Universal and Tetric N-Bond Universal on shear bond strength at zirconia–resin junction. Materials and Methods : Thirty CAD-CAM milled zirconia cylinders (5 mm × 8 mm) were sandblasted and divided into three groups: Group A (control) received no treatment, while Groups B and C were primed by One Coat 7 Universal and Tetric N-Bond Universal, respectively. They were luted to composite surfaces by a dual-curing resin cement. After 24 h, a shear bond strength test was conducted and failure mode was analyzed. Statistical Analysis: One-way analysis of variance and post hoc Tukey's test were used for statistical analysis. Results : Both One Coat 7 Universal (24.43 ± 2.66 MPa) and Tetric N-Bond Universal (28.61 ± 3.11 MPa) had significantly higher strength than the control group (9.86 ± 2.00 MPa). Control group underwent 100% adhesive failures. Experimental groups had predominantly mixed/cohesive failures. Conclusion : Both universal adhesives increased the bond strength at resin–zirconia junction. Tetric N-Bond Universal exhibited the highest strength. [ABSTRACT FROM AUTHOR]

Aim: Attempting to remove implant fractured screw usually damage fixture's internal threads, rendering osseo-integrated implant useless. The study aimed at testing a new technique, which salvages osseo-integrated implant with damaged internal threads, using post and core, thus retaining the prosthesis. Materials and Methods: Posts and cores are fabricated from Zirconia and Nickel Cromium (NiCr). Specimens were divided into seven groups (n = 10) depending on material and duration of function: Group 1: Zirconia immediate placement; Group 2: NiCr immediate placement; Group 3: Zirconia after five months of function; Group 4: NiCr after five months of function; Group 5: NiCr after one year of function; Group 6: NiCr after two years of function; and Group 7: NiCr after three years of function. Fatigue resistance test was applied followed by tensile bond strength test to the surviving specimens. Scanning Electron Microscope (SEM) test was applied to random bonded and de-bonded specimens. Data were analyzed using analysis of variance (ANOVA), Tukey's post hoc, and Chi-square test to detect significance at P = 0.05. Results: All Zirconia specimens were fractured and were not dislodged in fatigue resistance testing; hence their results were excluded from statistical analysis. All NiCr specimens in the fatigue resistance test in the five-month, one-year, and two-year duration groups were successfully retained. However, 40% of the specimens in the three-year duration group were dislodged. The tensile bond strength test showed no significant results up to the first-year duration group, whereas the bond strength decreased by 16.32% in the two-year duration group and 54.32% in the three-year duration group. The SEM testing of a random bonded specimen showed a continuous cement layer. Further, the de-bonded specimen showed generalized adhesive/cohesive fractures in the cement layer. Conclusion: NiCr posts and cores succeeded in two-year function, but they may need a three-year follow-up for performing the re-cementation procedure. [ABSTRACT FROM AUTHOR]

Background: There are conflicting results concerning the ideal time for etching primary dentin and its effect on the bond strength of adhesive restorative materials.Aim: To assess in vitro, the effect of varied acid concentration and etch time on the morphological features and tensile bond strength of primary dentin.Materials and Methods: Forty healthy primary molars were prepared by exposing the dentin of the occlusal surface, creating a smear layer. A 3 mm × 3 mm test indow was demarcated, and specimens were randomly allocated to four groups (n = 10): Group 1A 10% phosphoric acid, 7 s; Group 1B 10% phosphoric acid, 15 s; Group 2A 37% phosphoric acid, 7 s and Group 2B 37% phosphoric acid, 15 s. Surface analysis was done using atomic force microscope and scanning electron microscope. For tensile bond strength evaluation, 24 specimens prepared as mentioned were mounted in acrylic blocks and allocated to four groups according to the prescribed etching protocol. Resin rods were bonded and tested in tension after 24 h (n = 6). Data were analyzed statistically using unpaired t-test.Results: Etching of primary dentin using 37% phosphoric acid for 7 s produced the highest tensile bond strength of 9.51 ± 2.19 MPa.Conclusion: Etching time of 7 s may improve the adhesion of resin restorative materials with primary dentin. [ABSTRACT FROM AUTHOR]

Background: Increased risk of enamel demineralization during and after orthodontic treatment raises the demand for better preventive measures including combinations of laser, CPP-ACP, and fluoride. The combination of Er,Cr:YSGG laser with CPP-ACP was proved to have a synergetic effect compared to each of them alone. Shear bond strength (SBS) of orthodontic brackets bonded to the enamel surface after being treated with preventive measures is critical. The aim of this study was to compare the SBS and failure mode of metallic brackets bonded to teeth with no pretreatment and pretreated enamel surface, either with Er,Cr:YSGG laser alone or combined with CPP-ACP. Methods: Sixty sound extracted human premolar teeth were allocated randomly to 3 groups: In Group 1 (control), teeth were etched and bonded directly; in Group 2, laser pretreatment of the enamel surface was done followed by etching and bonding as in the control group; in Group 3, the enamel surface was lased then CPP-ACP was applied according to the manufacturer instructions, etched and bonded. SBS and Adhesive remnant index (ARI) were evaluated. Results: No significant differences were found between the 3 groups neither in the SBS nor in the ARI scores. Conclusions: The use of combined Er,Cr:YSGG laser with CPP-ACP as a preventive measure before bonding orthodontic brackets does not endanger the bracket's bonding strength. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the ability of modified phosphoric acids containing chlorhexidine (CHX) or grape seed extract (GSE) for promoting simultaneous biomodification during acid etching on bonding properties in caries-affected dentin (CAD). Materials and methods: Thirty-two human molars (8 with sound dentin [SD] and 24 naturally CAD) were selected for the study. The SD and CAD were initially exposed, then randomized and etched according to the following groups: (1) SD (SD-CT) and CAD (CAD-CT) both with 37% phosphoric acid, (2) CAD with 2% CHX containing 37% phosphoric acid (CAD-CHX), and (3) CAD with 2% GSE containing 10% phosphoric acid (CAD-GSE). The bonding procedure and composite build-ups were performed after acid etching. Subsequently, they were sectioned in resin-dentin specimens. The specimens were submitted for chemical profiling by micro-Raman, microtensile bond strength (μTBS), failure mode with chemical characterization by FEG/SEM-EDX, and in situ zymography by CLSM. The data from μTBS and CLSM were statistically analyzed (1-way ANOVA and Tukey's test; α = 0.05). Results: The highest μTBS results were shown for SD-CT in comparison with all CAD groups (p < 0.001), and the lowest for CAD-CT and CAD-CHX (p < 0.001). The etching with CHX did not increase the μTBS for CAD when compared with CT (p = 0.52). However, the etching with GSE improved significantly the μTBS for CAD when compared with CT and CHX (p < 0.001). The chemical profile detected chemical and structural changes in collagen peaks for CAD-CT, which were not detected when the CAD was etched by modified acids. Also, the poorest hybridization ability was detected in CAD for CT, which was significantly improved with modified acids, especially the GSE, as evaluated by chemical profile and failure mode. A significant reduction of MMP activity on CAD was promoted by modified acids in comparison with CT (both p < 0.001). Conclusions: The GSE-containing acid was able to promote biomodification during the acid etching, increasing the bonding properties and reducing the activity of the MMPs within the hybrid layer. Clinical relevance: The use of GSE-containing phosphoric acid can be a promising alternative to improve the bonding performance on caries-affected dentin, since it is capable of biomodifying the dentin during the acid etching, without adding any extra step in bonding procedures. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this randomized clinical trial (RCT) was to compare the shear bond strength (SBS) of orthodontic brackets bonded to enamel with conventional acid-etch (AE) technique and self-etching primers (SEP). Materials and Methods: Twenty-two patients, requiring extraction of two bicuspids for orthodontic reasons, were recruited. In each individual, following blinding and allocation concealment, one intact premolar received conventional AE, whereas the contralateral premolar received SEP with a split-mouth design. Bonded brackets remained in the oral cavity for two months. Afterward, the teeth were extracted without debonding the brackets. SBS and adhesive remnant index (ARI) were measured using a Universal Instron machine and a stereomicroscope, respectively. Results: The mean SBS of the conventional AE and SEP groups was 9.53 and 9.20 MPa, respectively. Paired t-test showed no statistically significant difference between the two groups (P=0.096). Comparison of ARI between the two groups, using Wilcoxon test, indicated that significantly less adhesive remained on enamel with brackets bonded with SEP compared to brackets bonded with conventional AE (P

Juliana Costa Pereira Baia,1 Mara Eliane Soares Ribeiro,1 Bárbara Catarina Lima Nogueira,1 Rafael Rodrigues Lima,2 Mário Honorato da Silva e Souza Júnior,1 Sandro Cordeiro Loretto1 1Department of Restorative Dentistry, UFPA – Federal University of Pará, Belém, PA, Brazil; 2Laboratory of Structural and Functional Biology, UFPA – Federal University of Pará, Belém, PA, Brazil Aim: The aim of this study was to compare the bonding strength of dental materials in buffalo (Bubalus bubalis var. kerebau), bovine, and human enamel and the susceptibility of these substrates in acid etching.Materials and methods: A total of 20 human third molars, 20 bovine incisors, and 20 buffalo incisors were used in a mechanical assay of microshear. The substrates were demineralized via conditioning with 37% phosphoric acid, and the ultra-morphological pattern of each substrate was analyzed by scanning electron microscopy.Results: The results showed that there was no significant difference in adhesive bonding strength values between buffalo and human enamel (P≥0.05), with a fracture pattern of mixed type for all experimental groups.Conclusion: The results indicate that buffalo enamel is similar to human dental substrate in tests of adhesive bonding strength and also show a similar behavior in the acid conditioning of the enamel. Keywords: dental enamel, shear strength, dental acid etching, scanning electron microscopy

Purpose: To assess differences in neodymium:yttrium aluminum garnet (Nd:YAG)-induced defects in hydrophilic and hydrophobic intraocular lenses (IOLs) and describe optical and surface properties of YAG shots/pitting. Describing and measuring the iatrogenic produced defects should achieve higher awareness on this topic and change the mindset of such a trivial procedure to be proceeded with more caution and calmness in the future. Materials: Twelve IOLs from different manufacturers made of hydrophilic and hydrophobic materials were evaluated before and after treatment with the Nd:YAG laser. Microscopy and environmental scanning electron microscopic (ESEM) images were used to visually analyze the defects. Additionally, wavefront measurements were taken for power mapping and Raman spectroscopy was performed. Vertical and horizontal dimensions of the defects were analyzed and compared, and Raman line scans assessed the changes in the chemical structure in the defect area of the IOL. Results: Microscopically, pitting of the surface could be observed in both lens types. Defects in hydrophobic lenses appeared bigger and were visible with less magnification than in hydrophilic lenses. Similar results were obtained with ESEM images where the defects in hydrophobic IOLs seemed to be frayed while defects in hydrophilic IOLs were of circular shape. Raman spectroscopy revealed deeper defects in hydrophobic lenses. Vertical dimensions of the defects were statistically significant (p = 0.036) and greater in hydrophobic materials while horizontal dimensions did not reach significance (p = 0.056). The area of chemical changes was greater than the visible defect area and smaller in hydrophilic than that in hydrophobic materials. Conclusion: Nd:YAG seems to have greater impact on hydrophobic IOL materials as that damage was greater and more frayed than that in hydrophilic materials. Moreover, there seems to be larger, distinctive damage area in IOLs (with chemical changes in the material) than that is visually recognizable. Therefore, a very cautious approach is recommended when performing capsulotomy, as defects in the surface structure can occur. This might come along with problems in quality of vision in monofocal and primarily premium IOLs (multifocal, enhanced depth of focus, and toric IOLs), dependent on the size, dimension, and position in the IOL. YAG capsulotomy should not be considered trivial but should be carried out with precision and without time pressure, just like surgery itself. [ABSTRACT FROM AUTHOR]

This study aimed at determining the enamel bond durability of universal adhesives to intact enamel (IE) and ground enamel (GE) in different etching modes under thermal cycling (TC) and fatigue stresses. Two universal adhesives and a two‐step self‐etch adhesive were used. Enamel specimens were divided into four groups by treatment: (i) GE in etch‐and‐rinse, (ii) IE in etch‐and‐rinse, (iii) GE in self‐etch, and (iv) IE in self‐etch. Bonded specimens were subjected to TC, and then shear bond strengths (SBS) were conducted. SBS tests were also conducted after storage in 37°C water for 24 h (baseline). For shear fatigue strength (SFS) testing, bonded specimens were subjected to fatigue stress at a frequency of 10 Hz for 50,000 cycles. At baseline, all adhesives showed significantly higher SBS values with GE than IE in self‐etch mode in contrast to in etch‐and‐rinse mode. After TC, the universal adhesives with IE showed lower SBS values than the baseline, regardless of the etching mode. Universal adhesives showed significantly lower SFS values with IE in etch‐and‐rinse, but not in self‐etch mode. Phosphoric acid pre‐etching or grinding of the aprismatic enamel may be helpful in establishing reliable initial and long‐term bonds to enamel when using universal adhesives in self‐etch mode. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinical behavior of a universal light-curing, ultra-fine particle hybrid composite and successor of this material in class I and II cavities after 60 months. Materials and methods: Forty patients (21 females, 19 males) with ages ranging between 18 and 38 years (23.15 ± 5.15) received 80 (13 Cl I and 67 Cl II) resin composite restorations (Charisma/Charisma Classic, Kulzer GmbH) in combination with an etch and rinse adhesive system (Gluma 2Bond) under rubber dam isolation. Two experienced operators performed all the restorations. Restorations were evaluated by the other two examiners according to the FDI criteria at baseline and at 6, 12, 18, 24, 36, 48 and 60 months. Surface characteristics of one restoration selected randomly were examined under a scanning electron microscope (SEM) at each recall. Data were analyzed statistically (p < 0.05). Results: After 60 months, recall rate was 90%. None of the restorations failed. Three restorations from Charisma and 4 from the Charisma Classic group showed minor surface staining. Twelve Charisma and 14 Charisma Classic restorations were scored as 2 for margin staining. Four restorations from both groups showed minor shade deviations but no significant difference was observed between the two restorative materials for any criteria evaluated after 60 months (p > 0.05). SEM evaluations were in accordance with the clinical findings. Conclusions: Both materials exhibited clinically similar and successful performance over the 60-month observation period. Clinical relevance: A new formulation of resin composite may not always perform better clinical performances. Trial registration: ClinicalTrials.gov: NCT02888873 [ABSTRACT FROM AUTHOR]

Objective: To evaluate the microshear bond strength (μSBS) of resin cement to a lithium disilicate glass ceramic conditioned with different surface treatment procedures. Methods: Crystallised slices of lithium disilicate glass ceramic were randomly divided into five groups (n = 10) according to different surface treatment procedures: the no surface treatment (NT) group was untreated; the hydrofluoric acid (HF) group was conditioned with 4.5% HF; the silane (S) group was conditioned with a silane coupling agent; the hydrofluoric acid and silane (HFS) group was conditioned with HF followed by the silane coupling agent; and the Monobond Etch & Prime (MEP) (Ivoclar Vivadent, Schaan, Liechtenstein) group was conditioned with the one-step self-etching primer MEP. Resin cement was applied to the ceramic surfaces and irradiated. A μSBS test was performed. Failure analysis, surface roughness tests, surface topography examination and elemental analysis were also conducted. The data were analysed with a one-way analysis of variance (ANOVA) and Tukey honestly significant difference test (P < 0.05). Results: The MEP group resulted in comparable μSBS to the HFS group (16.9 ± 4.3 MPa and 16.0 ± 2.2 MPa, respectively), but a significantly higher μSBS than the NT (1.0 ± 0.9 MPa), HF (8.9 ± 3.9 MPa) and S (12.6 ± 2.5 MPa) groups. Adhesive failure was mainly observed in the NT and HF groups, while the S, HFS and MEP groups demonstrated the most mixed failure. Though micrographs revealed a roughened surface in the HF group, no significant difference was found with any other groups. Conclusion: Within the limitations of this study, it can be concluded that the μSBS of resin cement to lithium disilicate glass ceramic etched with MEP is as efficient as that treated with HF and silane. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the shear bond strength (SBS) of ceramic discs luted to differently etched enamel and dentin surfaces. Occlusal surfaces of 64 carious-free human molars and vestibule surfaces of 64 first maxillary incisors were ground to get flat superficial dentin and flattened enamel respectively. After generating 4 groups according to the surface etching method (37% orthophosphoric acid, Er:YAG laser-contact handpiece/scanning handpiece (1 or 2 times of scanning)), ceramic discs were luted to the surfaces with adhesive resin cement (Variolink N, Vivadent Ets., Schaan/Liechtenstein). After etching and cementation, thermocycling of 5000 cycles (Sd Mechatronık Gmbh, Feldkirchen-Westerham, Germany) and SBS test (Servopulser EHFFD1; Shimadzu, Kyoto, Japan) were performed respectively. The surface morphologies of 2 specimens, etched enamel and dentin, prepared for each group were examined with SEM analysis. Failure modes were determined under a USB digital microscope. Data were analyzed with one-way analysis of variance (ANOVA) and Tukey HSD test (α = 0.05). SBS values in dentin surfaces showed statistically significant differences (p < 0.05) among tested groups. The highest SBS among dentin groups was determined in the group which had 2 times etching by Er:YAG laser (11.42 MPa) by a scanning handpiece. No statistical differences were observed in the other dentin or enamel groups. Laser etching seems to be a viable alternative to acid etching on both enamel and dentin surfaces while double etching of dentin with a scanning handpiece can improve the adhesion. [ABSTRACT FROM AUTHOR]

Aim: To compare the clinical performance of composite restorations placed with a universal adhesive, one-step and two-step self-etch adhesives in class I and II posterior cavities. Materials and methods: In this in vivo study, 46 volunteers presenting with at least three carious lesions were included. Each participant received the three restorative systems: universal adhesive/nanofilled composite (Scotchbond Universal/Filtek Z350 XT: SBU/FZXT), one-step selfetch adhesive/microhybrid composite (G-aenial bond/G-aenial Posterior: GB/GP) and the twostep self-etch adhesive/nanohybrid composite (OptiBond XTR/Herculite Ultra: OBX/HU). The adhesives were all placed in self-etch mode. In total, 138 restorations were evaluated at baseline and at 6,12 and 36months using the modified United States Public Health Service criteria. Data were analysed using Kruskal-Wallis, Mann-Whitney U, Friedman and Wilcoxon non-parametric tests (p<.05). Ninety-one restorations were evaluated at 36months. Results: Seven restorations, three SBU/FZXT, three GB/GP and one OBX/HU failed during this study. The reasons for failure were marginal fracture and secondary caries. SBU/FZXT restorations showed significant marginal deterioration in all parameters. Overall success rates were: 93.5% (SBU/FZXT), 96.6% (GB/GP) and 96.8% (OBX/HU). Conclusions: After three years, the three restorative systems have comparable clinical effectiveness and success rates, except for the marginal integrity, that was suboptimal for both the SBU/FZXT and GB/GP restorations in comparison to the OBX/HU restorations. [ABSTRACT FROM AUTHOR]