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Do ozonated water and boric acid affect the bond strength to dentin in different adhesive systems?
Akturk, E, Bektas, OO, Ozkanoglu, S, G Akin, EG
Nigerian journal of clinical practice. 2019;(12):1758-1764
Abstract
AIM: The aim of this in vitro study was to compare the effects of the application of three different cavity disinfecting agents to dentin on the micro-shear bond strength (μ-SBS) of one self-etch and two universal adhesive systems. MATERIALS AND METHODS In total, 120 caries-free human permanent molar teeth were used in this study. Mid-coronal dentin surfaces were revealed by cutting occlusal enamel and a standard smear layer was obtained by using 600-800-1200 grid silicon carbide abrasive papers. Specimens were randomly assigned to four groups according to the disinfectant used: Group 1: Control (no disinfectant); Group 2: 2% chlorhexidine based (Consepsis); Group 3: 10 ppm ozonated water (TeknO3zone); Group 4: 5% boric acid (Handmade). Each group was divided into three subgroups according to the type of adhesive (Clearfil SE Bond, OptiBond XTR, and Tokuyama Universal). Specimens were bonded using either Clearfil SE Bond, OptiBond XTR or Tokuyama Universal, which were employed according to the manufacturer's instructions. Resin composite microcylinders were bonded using Tygon® tubes for μ-SBS testing. After specimens were stored for 24 h, at 37°C in distilled water, μ-SBS test was measured with a universal test machine (LF Plus, Lloyd, Instrument). μ-SBS results were analyzed by one-way analysis of variance (ANOVA) and Tukey's tests. RESULTS When the mean microshear bond strength values of the control group were compared, the difference between the subgroups was not significant (P < 0.05). When the mean microshear bond strength values of the chx, ozonated water, and boric acid were compared, the difference between Clearfil SE Bond and Tokuyama Universal was significant (P < 0.05) and the difference between the other groups was not significant (P > 0.05). CONCLUSION Ozonated water and boric acid may be as an alternative to other materials used as cavity disinfectants.
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Microcomputed Tomography Evaluation of Dentine Mineral Concentration in Primary Molars Managed by Three Treatment Protocols.
Mijan, MC, Frencken, JE, Schwass, DR, Chaves, SB, Leal, SC
Caries research. 2018;(4):303-311
Abstract
The objectives of the study were to quantify the dentine mineral concentration (DMC) in teeth restored conventionally, according to the atraumatic restorative treatment (ART) and ultraconservative (UCT) protocols (open cavities and small ART restorations), and the DMC underneath the open cavities of teeth managed by UCT versus nontreated, open cavities. We studied 50 teeth with restorations/open cavities, 39 restored teeth (9 by conventional restorative treatment [CRT], 17 by ART, and 13 by UCT) and 16 teeth with open cavities. Each restoration/open cavity was scanned using microcomputed tomography, with 3 hydroxyapatite disks with respective densities of 1.24, 1.33, and 1.57 g/cm3 as a reference. Images were reconstructed and the greyscale images were converted into DMC values. For each restoration/open cavity, 15 measurements of dentine immediately underneath and from the corresponding area in sound dentine were taken. DMC was expressed as a percentage of the DMC of sound dentine. ANOVA and the Student t test were used for statistical analysis. The mean DMC underneath restorations of the ART protocol group (98.93%) was statistically significantly higher than that of the UCT protocol group (91.98%), but not of the CRT protocol group (91.33%). On multiple surfaces, mean DMC in the axial area (94.32%) was statistically significantly higher than in the gingival area (92.80%). The mean DMC of open cavities managed by UCT protocol (89.05%) was statistically significantly higher than in nontreated open cavities (83.90%). In conclusion, a dentine-hypermineralized area underneath ART restorations was observed. Managing open cavities with a toothbrush and fluoride toothpaste (the UCT protocol) resulted in higher mineralized dentine underneath the cavity than in nontreated open cavities.
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Response of periodontium to mineral trioxide aggregate and Biodentine: a pilot histological study on humans.
Tirone, F, Salzano, S, Piattelli, A, Perrotti, V, Iezzi, G
Australian dental journal. 2018;(2):231-241
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Abstract
BACKGROUND The aim of this study was to investigate for the first time the histological response of human periodontium to mineral trioxide aggregate (MTA) and Biodentine. METHODS Six patients scheduled for implant full-arch rehabilitation were randomly assigned to one of the two test groups: MTA or Biodentine treatment. For each patient, two teeth scheduled for strategic extraction were randomly assigned either to the test or to the control treatment. A lateral perforation was drilled on the root and either repaired with MTA/Biodentine or filled with gutta-percha(control). Three months later, the teeth were extracted along with the coronal third of the alveolar bone and a portion of gingival tissue, while performing implant placement, and processed for histological analysis. RESULTS Biodentine resulted in less extrusion into the periodontal environment. All the materials showed good biocompatibility. A new mineralized cementum-like tissue incorporating periodontal fibres was visible in all cases treated with MTA. A small amount of new mineralized tissue was found in two Biodentine cases but not in control cases. Biodentine resulted in less damage to the periodontal ligament. CONCLUSIONS Bioactivity and biocompatibility of MTA were confirmed in human models. Biodentine proved to be biocompatible, but it seems not to induce cementum regeneration.
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Randomised clinical trial to evaluate changes in dentine tubule occlusion following 4 weeks use of an occluding toothpaste.
Seong, J, Parkinson, CP, Davies, M, Claydon, NCA, West, NX
Clinical oral investigations. 2018;(1):225-233
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Abstract
OBJECTIVES The objective of this study is to determine whether a silicone impression material could precisely replicate dentine tubule changes following 4 weeks toothbrushing with occluding or non-occluding toothpaste and whether changes reflected hypersensitivity clinical assessment. MATERIALS AND METHODS This was a single site, examiner blind, parallel, two treatment arm, randomised clinical trial. Participants were healthy, ≥18, with ≥1 sensitive tooth with exposed dentine, Schiff sensitivity score ≥2, and patent tubules with dentine occlusion score 4-5 as determined by scanning electron microscopy of replica impressions. Nine participants received Sensodyne® Rapid Relief (occluding toothpaste) and 10 Crest® Decay Prevention (non-occluding toothpaste), and were re-evaluated for sensitivity and occlusion score after two timed minutes and 4 weeks twice-daily home brushing. RESULTS Occlusion scores did not correlate significantly with pain scores, but correlations were positive and impressions showed characteristic dentine tubule patency and occlusion. After 4 weeks, thermal VAS was significantly lower than baseline for the non-occluding toothpaste; all other pain scores were significantly lower for both treatments. Dentine occlusion scores also decreased after 4 weeks of either treatment, but did not achieve significance (p = 0.0625). CONCLUSIONS Both toothpastes reduced clinical sensitivity and increased tubule occlusion. It is hypothesised that during impression, taking some material may have sheared off and occluded tubules resulting in false positives. CLINICAL RELEVANCE This study has demonstrated that a silicone impression material can accurately replicate the dentine surface to demonstrate dentine tubular occlusion and patency; however, although the association between occlusion and pain score was positive, this technique needs to be refined before use in future studies.
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Effect of postoperative peroxide bleaching on the stability of composite to enamel and dentin bonds.
Dudek, M, Roubickova, A, Comba, L, Housova, D, Bradna, P
Operative dentistry. 2013;(4):394-407
Abstract
This study investigated the effect of peroxide bleaching gel on the durability of the adhesive bond between composite material, enamel, and dentin created with the etch-and-rinse adhesive Gluma Comfort Bond (GLU) and with the self-etch adhesives Clearfil SE Bond (CLE), Adper Prompt (ADP), and iBond (IBO). The adhesives were applied to flattened enamel and dentin of extracted human molars and built up with a microhybrid composite (Charisma). After 25 eight-hour cycles of bleaching with a 20% carbamide peroxide bleaching gel (Opalescence PF 20), the shear bond strength was measured and compared with one-day and two-month control specimens stored in water. The data were analyzed using nonparametric Mann-Whitney and Kruskal-Wallis statistics (p<0.05). Detailed fractographic analysis was performed using scanning electron microscopy. The bleaching gel significantly decreased the bond strength on both enamel and dentin for the simplified single-step self-etch adhesives ADP and IBO and markedly affected a fracture pattern of ADP specimens at the periphery of their bonded area. The results of our study indicate that the durability of adhesive restorations can be detrimentally influenced by carbamide peroxide bleaching and that different adhesives show varying sensitivity levels to the bleaching gel.
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Immediate bonding properties of universal adhesives to dentine.
Muñoz, MA, Luque, I, Hass, V, Reis, A, Loguercio, AD, Bombarda, NH
Journal of dentistry. 2013;(5):404-11
Abstract
OBJECTIVES To evaluate the dentine microtensile bond strength (μTBS), nanoleakage (NL), degree of conversion (DC) within the hybrid layer for etch-and-rinse and self-etch strategies of universal simplified adhesive systems. METHODS forty caries free extracted third molars were divided into 8 groups for μTBS (n=5), according to the adhesive and etching strategy: Clearfil SE Bond [CSE] and Adper Single Bond 2 [SB], as controls; Peak Universal Adhesive System, self-etch [PkSe] and etch-and-rinse [PkEr]; Scotchbond Universal Adhesive, self-etch [ScSe] and etch-and-rinse [ScEr]; All Bond Universal, self-etch [AlSe] and etch-and-rinse [AlEr]. After restorations were constructed, specimens were stored in water (37°C/24h) and then resin-dentine sticks were prepared (0.8mm(2)). The sticks were tested under tension at 0.5mm/min. Some sticks from each tooth group were used for DC determination by micro-Raman spectroscopy or nanoleakage evaluation (NL). The pH for each solution was evaluated using a pH metre. Data were analyzed with one-way ANOVA and Tukey's test (α=0.05). RESULTS For μTBS, only PkSe and PkEr were similar to the respective control groups (p>0.05). AlSe showed the lowest μTBS mean (p<0.05). For NL, ScEr, ScSe, AlSe, and AlEr showed the lowest NL similar to control groups (p<0.05). For DC, only ScSe showed lower DC than the other materials (p<0.05). CONCLUSIONS Performance of universal adhesives was shown to be material-dependent. The results indicate that this new category of universal adhesives used on dentine as either etch-and-rinse or self-etch strategies were inferior as regards at least one of the properties evaluated (μTBS, NL and DC) in comparison with the control adhesives (CSE for self-etch and SB for etch-and-rinse).
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Bond strength of different resin cement and ceramic shades bonded to dentin.
Passos, SP, Kimpara, ET, Bottino, MA, Júnior, GC, Rizkalla, AS
The journal of adhesive dentistry. 2013;(5):461-6
Abstract
PURPOSE To evaluate the microtensile bond strength (MTBS) of ceramic cemented to dentin varying the resin cement and ceramic shades. MATERIALS AND METHODS Two VITA VM7 ceramic shades (Base Dentine 0M1 and Base Dentine 5M3) were used. A spectrophotometer was used to determine the percentage translucency of ceramic (thickness: 2.5 mm). For the MTBS test, 80 molar dentin surfaces were etched and an adhesive was applied. Forty blocks (7.2 x 7.2 x 2.5 mm) of each ceramic shade were produced and the ceramic surface was etched (10% hydrofluoric acid) for 60 s, followed by the application of silane and resin cement (A3 yellow and transparent). The blocks were cemented to dentin using either A3 or transparent cement. Specimens were photoactivated for 20 s or 40 s, stored in distilled water (37°C/24 h), and sectioned. Eight experimental groups were obtained (n = 10). Specimens were tested for MTSB using a universal testing machine. Data were statistically analyzed using ANOVA and Tukey's post-hoc tests (α <= 0.05). RESULTS The percentage translucency of 0M1 and 5M3 ceramics were 10.06 (± 0.25)% and 1.34 (± 0.02)%, respectively. The lowest MTBS was observed for the ceramic shade 5M3. For the 0M1 ceramic, the A3 yellow cement that was photocured for 20 s exhibited the lowest MTBS, while the transparent cement that was photocured for 40 s presented the highest MTBS. CONCLUSIONS For the 2.5-mm-thick 5M3 ceramic restorations, the MTBS of ceramic cemented to dentin significantly increased. The dual-curing cement Variolink II photocured for 40 s is not recommended for cementing the Base Dentine 5M3 feldspathic ceramic to dentin.
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Effect of three different contamination removal methods on bond strength of a self-etching adhesive to dentin contaminated with an aluminum chloride hemostatic agent.
Ajami, AA, Kahnamoii, MA, Kimyai, S, Oskoee, SS, Pournaghi-Azar, F, Bahari, M, Firouzmandi, M
The journal of contemporary dental practice. 2013;(1):26-33
Abstract
AIM: This study evaluated the effect of three different contamination removal methods on bond strength of one-step self-etching adhesive to dentin contaminated with an aluminum chloride hemostatic agent. MATERIALS AND METHODS One hundred noncarious adult molars were used in this study; 2-mm-thick dentin disks were prepared and randomly assigned to 5 groups (n = 20). Group I: control; group II: hemostatic agent-contaminated; group III: hemostatic agent-contaminated and rinsing with water; group IV: hemostatic agent-contaminated and ethylene diamine tetraacetic acid (EDTA) application; and group V: hemostatic agent-contaminated and phosphoric acid application. Clearfil S3 Bond was used to bond composite to dentin surfaces. Subsequent to adding composite cylinders the shear bond strength test was performed. Data were analyzed by one-way ANOVA and Tukey test. Two additional specimens from each group were prepared and evaluated under scanning electron microscope (SEM). RESULTS There were statistically significant differences in bond strength among the groups (p < 0.001). In two-by-two comparisons statistically significant differences were observed in bond strength values between all the groups (p < 0.001) except for groups I and IV (p = 0.933). CONCLUSION Aluminum chloride hemostatic agent adversely affected the bond strength of self-etch adhesive to dentin. However, application of EDTA increased the bond strength to the level of normal dentin. CLINICAL SIGNIFICANCE EDTA and phosphoric acid removed aluminum chloride hemostatic agent contamination of dentin surfaces. However, unlike EDTA phosphoric acid failed to increase the bond strength of self-etch adhesive to dentin to the level of the control group.
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A new fixation method for stick-shaped specimens in microtensile tests: laboratory tests and FEA.
Lu, S, Zhao, SJ, Wang, WG, Gao, Y, Zhang, Y, Dou, Q, Chen, JH
The journal of adhesive dentistry. 2013;(6):511-8
Abstract
PURPOSE To introduce a new fixation method for stick-shaped specimens for use in microtensile tests and to evaluate the effect of this new method on microtensile bond strength, failure modes, and stress distribution. MATERIALS AND METHODS Flat mid-coronal dentin surfaces were prepared on 12 caries-free human third molars and randomly divided into two groups for testing with two dental adhesives (Adper Single Bond 2 [SB2] and Clearfil SE Bond [SEB]). Following adhesive application and composite buildups, the bonded teeth were sectioned into beams. Sticks from each tooth were then equally divided into two subgroups for microtensile bond testing according to the utilized gripping devices (a flat Ciucchi's jig and the experimental setup). Failure modes were examined with a field-emission scanning electron microscope (FESEM). Three-dimensional models of each gripping device and specimen were developed, and stress distributions were analyzed by finite element analysis (FEA). Statistical significance was set at α = 0.05 RESULTS Compared to those fixed using a flat Ciucchi's jig, sticks fixed with the experimental setup yielded lower bond strength values (p = 0.021 for SB2 and p = 0.007 for SEB) and more mixed failure patterns (p = 0.036 for both SB2 and SEB). In addition, the experimental setup guaranteed a uniaxial tensile force that was perpendicular to the bonding interface and produced a more uniform stress distribution at the bonding interface. CONCLUSION An experimental setup for fixing microtensile sticks was proposed that was designed to provide a uniform stress distribution at the adhesive interface. FEA and failure mode analysis confirmed such uniform distribution, thus supporting the validity of the bond strength results obtained with this new fixture design.
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Effect of polyacrylic acid on the interface and bond strength of self-adhesive resin cements to dentin.
Stona, P, Borges, GA, Montes, MA, Júnior, LH, Weber, JB, Spohr, AM
The journal of adhesive dentistry. 2013;(3):221-7
Abstract
PURPOSE To examine the influence of 11.5% polyacrylic acid pretreatment on the interface and bond strength of self-adhesive resin cements (Maxcem Elite, RelyX Unicem, SeT) to dentin. MATERIALS AND METHODS Fifty-six third molars were randomly divided into seven groups: RelyX ARC as control (ARC), RelyX Unicem (RLXU), Maxcem Elite (MCE), SeT (ST), polyacrylic acid+RelyX Unicem (RLXU-P), polyacrylic acid+Maxcem Elite (MCE-P), and polyacrylic acid+SeT (ST-P). Resin composite blocks were luted to flat dentin. After storage in distilled water for 24 h, sticks with a cross-sectional area of ca 0.80 mm2 were obtained (n = 24 per group) and submitted to a microtensile bond strength (µTBS) test in a universal testing machine at a crosshead speed of 0.5 mm/min. Two sets from each group were sectioned mesiodistally in the center of the crown and observed with a scanning electron microscope at 4000X magnification. RESULTS The mean results of the µTBS test (MPa) followed by the same letter do not differ statistically significantly according to ANOVA and Tukey's post-hoc test (p < 0.05): ARC = 24.19 (± 6.90)a, RLXU-P = 23.12 (± 6.18)a, MCE-P = 13.09 (± 5.87)b, RLXU = 10.23 (± 2.88)b,c, and MCE = 8.14 (± 4.63)c. All SeT specimens failed during the cutting procedure. The hybrid layer was not observed for the self-adhesive resin cements, and resin tags were observed for RelyX Unicem and Maxem Elite when dentin was pretreated with polyacrylic acid. CONCLUSION Pretreatment with 11.5% polyacrylic acid was effective for bonding RelyX Unicem and Maxcem Elite to dentin.