Comparative Evaluation of Laser Etching and Acid Etching: An in vitro Study

2016 ◽  
Vol 6 (1) ◽  
pp. 6-11 ◽  
Author(s):  
Varsha V Sobha ◽  
NK Sapna Varma ◽  
VV Ajith

ABSTRACT Introduction Recent innovations in bonding propose laser ablation as an alternative method to acid etching. Objectives The objective of this study is to compare the effect of laser irradiation at medium-short pulse (MSP) mode, quantum-square pulse (QSP) mode, and acid etching on the shear bond strength (SBS) of orthodontic brackets to enamel. Materials and methods Forty-two premolars were allocated to three groups (14 each): (1) 37% phosphoric acid etching; (2) erbium-doped yttrium aluminum garnet (Er:YAG) laser etching with MSP mode; (3) Er:YAG laser etching with quantum-square pulse mode. Metallic brackets were bonded with Transbond XT. After photo polymerization, the SBS values were recorded with universal testing machine. Surface morphology was evaluated with scanning electron microscopy (SEM). The remaining adhesive was assessed using adhesive remnant index (ARI). Results Nonparametric test was used to analyze the statistical significance. A mean rank of 18.29 and 10.71 was obtained for QSP mode and acid etching with p = 0.015, 18.14; and 10.86 for MSP mode and acid etching with p = 0.019; and 14 and 15 for QSP mode and MSP mode with p = 0.748. Statistically significant difference was found between laser and acid-etched group. The SEM scan showed MSP mode with regular and uniform surface, like acid-etched sample, whereas QSP samples had irregular and severely rough surface. The ARI indicates that failure sites are mainly at the enamel/adhesive interface in the acid-etched and MSP mode group and at the bracket base/adhesive interface in QSP mode group. Conclusion Laser etching in MSP mode is a successful alternative to acid etching, and provides a safer debonding of the brackets from the enamel surface without causing fractures. How to cite this article Sobha VV, Varma NKS, Ajith VV. Comparative Evaluation of Laser Etching and Acid Etching: An in vitro Study. Int J Laser Dent 2016;6(1):6-11.

2013 ◽  
Vol 83 (6) ◽  
pp. 973-980 ◽  
Author(s):  
Serkan Sağır ◽  
Aslıhan Usumez ◽  
Ebru Ademci ◽  
Serdar Usumez

ABSTRACT Objective: To compare the effect of laser irradiation at two different pulse settings and acid etching on the shear bond strength (SBS) of orthodontic brackets to enamel. Materials and Methods: Thirty-six premolars were allocated to three groups (n  =  12): (1) 37% phosphoric acid etching, (2) erbium-doped yttrium aluminum garnet (Er:YAG) laser etching with medium-short pulse mode (MSP; 100 µs, 120 mj, 10 Hz, 1.2 W), and (3) Er:YAG laser etching with quantum-square pulse mode (QSP; 120 mj, 10 Hz, 1.2 W). Metallic brackets were bonded with Transbond XT. After photopolymerization, the samples were subjected to 5000 thermal cycles and debonded with a universal testing machine, and the SBS values were recorded. Surface morphology was evaluated with profilometric examination, scanning electron microscopy, and atomic force microscopy. The adhesive remnant index (ARI) was evaluated to assess the remaining adhesive. Results: The results of SBS testing were analyzed by one-way analysis of variance and Tukey honestly significant diffference tests. The mean SBS values of QSP and MSP laser groups were 11.80 ± 2.7 MPa and 10.10 ± 4.5 MPa, respectively, and the QSP group demonstrated significantly higher SBS (P < .01) than that of the acid-etched group (6.6 ± 2.4 MPa). No significant difference was observed between the SBS values of the two laser groups (P < .05). The difference between the ARI scores of the laser groups and the acid-etched group was statistically significant (P < .05). Conclusion: Laser etching at MSP and QSP modes present successful alternatives to acid etching; however, long-term clinical studies are required to verify clinical success.


2021 ◽  
Vol 58 (1) ◽  
pp. eUJ3657
Author(s):  
Germano Brandão ◽  
◽  
Liliana Ávila Maltagliati ◽  
Ana Carla Raphaelli Nahás-Scocate ◽  
Murilo Matias ◽  
...  

The objective of this in vitro study was to assess and compare the shear bond strength of conventional and modified orthodontic tubes bonded to the surface of dry and saliva-contaminated enamel. The sample consisted of 40 human teeth, which were randomly divided into four groups according to attachment base and presence or absence of saliva contamination as follows: Group CB, conventional orthodontic tubes without salivary contamination; Group CB-S, conventional orthodontic tubes with salivary contamination; Groups BM, orthodontic tubes modified by welding a metal mesh to their base without salivary contamination; and Group BM-S, modified orthodontic tubes with salivary contamination. Shear bond strength test was performed in a universal testing machine and analysis of the adhesive remnant index (ARI) by optical microscopy. Two-way ANOVA was used, followed by Tukey’s test at a statistical significance level of 5%. The ARI results were analysed descriptively. There was statistically significant difference between the groups regarding the shear bond strength values, with conventional tubes presenting significantly higher values (P < 0.05). In addition, the presence of salivary contamination interfered negatively with the behaviour of conventional tubes only (P < 0.05). Shear bond strength was not improved by increasing the area of the orthodontic tubes. Moreover, salivary contamination influenced negatively the SBS values, but only when conventional tubes were used.


2018 ◽  
Vol 12 (03) ◽  
pp. 380-385 ◽  
Author(s):  
Abtesam Aljdaimi ◽  
Hugh Devlin ◽  
Mark Dickinson

ABSTRACTObjectives: The purpose of this study was to determine if Er: YAG laser etching improves the shear bond strength (SBS) of Biodentin™ and GC Fuji IX® to dentine. Materials and Methods: Forty human dentine specimens were standardized and embedded in stone. The specimens were randomized into four groups (n = 10). Twenty samples were treated with the Er: YAG laser radiation and 10 of these restored with GC Fuji IX® and 10 with Biodentine™. The remaining 20 specimens acted as controls (no laser treatment); 10 were restored with GC Fuji IX® and 10 with Biodentin™. All samples were then stored in an incubator at 37.5°C and 100% humidity for 7 days. The SBS was determined using a Zwick universal testing machine. A two-way analysis of variance test was used to evaluate the statistical difference in SBS between the groups. An independent sample t-test was used to determine the statistical significance of differences between control and lased groups within the same material. Results: A highly statistically significant difference in SBS was found with the laser treatment (P = 0.0001) and material (i.e., Biodentin™ or Fuji IX® (P = 0.0001). The GC Fuji IX® group recorded the highest mean SBS required to dislodge the material from the laser-treated dentine surface (1.77 ± 0.22 Mega-Pascal [MPa]). The mean SBS of Biodentin™ to dentine following the laser radiation (1.12 ± 0.16 MPa) was significantly greater compared to the nonlased dentine (0.53 ± 0.09). Pearson Chi-square test indicated a nonsignificant relation between shear strength and mode of failure (P = 0.467). Conclusion: Laser etching of the dentine surfaces yielded a significant increase in the bond strength for both GC Fuji IX® and Biodentin™. The SBS of Biodentin™ to dentine is greater than with conventional glass ionomer (Fuji IX®).


2014 ◽  
Vol 39 (6) ◽  
pp. E250-E260 ◽  
Author(s):  
TA Imbery ◽  
T Gray ◽  
F DeLatour ◽  
C Boxx ◽  
AM Best ◽  
...  

SUMMARY Objective Repairing composite restorations may be a more conservative treatment than replacing the entire restoration. The objective of this in vitro study was to determine the best repair method by measuring flexural, diametral tensile, and shear bond strength of repaired composites in which the surfaces were treated with chemical primers (Add & Bond or Silane Bond Enhancer), a bonding agent (Optibond Solo Plus [OBSP]), or mechanical retention with a bonding agent. Methods Filtek Supreme Ultra shade B1B was placed in special molds to fabricate specimens that served to test the flexural, diametral tensile, or shear strength of the inherent resin substrate. The same molds were modified to make specimens for testing repair strength of the resin. Repairs were made immediately or after aging in deionized water at 37°C for seven days. All repair sites were finished with coarse Sof-Lex discs to simulate finishing new restorations or partially removing aged restorations. Repair surfaces were treated with one of the following: 1) phosphoric-acid etching and OBSP; 2) Add & Bond; 3) phosphoric-acid etching, Silane Bond Enhancer, and OBSP; or 4) quarter round bur, phosphoric-acid etching, and OBSP. Specimens were placed back in the original molds to fabricate specimens for diametral tensile or flexural testing or in an Ultradent jig to make specimens for shear bond testing. Composite resin in shade B5B was polymerized against the treated surfaces to make repairs. Two negative control groups for the three testing methods consisted of specimens in which repairs were made immediately or after aging without any surface treatments. Controls and experimental repairs were aged (water 37°C, 24 hours) before flexural, diametral tensile, or shear testing in an Instron Universal testing machine at a crosshead speed of 0.5 mm/min. Results Experimental flexural repair strengths ranged from 26.4% to 88.6% of the inherent substrate strength. Diametral tensile repair strengths ranged from 40% to 80% of the inherent substrate strength, and shear bond strength repairs ranged from 56% to 102%. Geometric means were statistically analyzed with two-way analysis of variance on their log-transformed values. Significant differences were determined using Tukey honestly significant difference (p&lt;0.05). Conclusions Depending on the mechanical property being tested, surface treatments produced different results. OBSP produced more consistent results than chemical primers.


Author(s):  
Prasanna Laxmi Krishnappan ◽  
Ragavendra Jaiesh ◽  
TN Swaminathan

ABSTRACT Purpose This is an in vitro study for comparative evaluation of transverse bond strength, peel bond strength and water sorption properties between heat polymerized and auto-polymerized resins. Materials and methods Two denture soft liners (Molloplast-B, Coe-Soft) were investigated. A total number of 60 specimens were used. Twenty specimens were used for evaluation of each physical property of soft liner. For transverse bond strength, ten specimens (64 ⨯ 2.5 ⨯ 10 mm) of each liner were made by processing the denture liners with heat cure polymethyl methacrylate (Meliodent). All specimens for transverse bond strength were conducted on samples immersed in distilled water at 37°C for 50 hours by using three-point transverse flexural tests in a Lloyd's Universal Testing Machine and transverse bond strength was calculated based on the maximum load, span length, breadth and thickness. Another set of ten specimens of (75 ⨯ 25 ⨯ 3 mm) of each denture liner were bonded over 25 mm of heat cure PMMA and separated over the remaining 50 mm of acrylic plate to estimate the peel bond strength. The peel bond strength were conducted on specimens which were dried at room temperature for 48 hours and tested at 21 1 ± C in a Lloyd's testing machine that was linked to an IBM Compatible Computer. The specimens were deformed with a cross head speed of 5 mm/minute according to ASTMD-903 and peel bond strength was calculated when peel angle was 180°. For water sorption tests, ten disc shaped samples of each liner of 50 mm in diameter and 0.5 mm in thickness were fabricated. After polymerization of the liners, the samples were then stored in distilled water at 37°C for 7 days. After one week, excess moisture was removed and each sample was weighed using electronic weighing machine. Results The transverse bond strength of Molloplast-B and Coe-Soft were almost similar and did not show any significant difference in their values. But, there is a significant decrease in the peel bond strength and water sorption property of Molloplast-B and Coe-Soft. Conclusion The reason for transverse bond strength results being similar for both the liners is because they were polymerized chemically with the denture base resins and this chemical affinity could have made its bond strength almost equal. Since, there is a decrease in the peel bond strength of Molloplast-B, the chances of stripping of the liner at the flanges of the denture is minimal. The decrease in water sorption of Molloplast-B can be expected to retain the bond with the denture and sustain the resilience property of the material for a longer time. How to cite this article Krishnappan PL, Jaiesh R, Swa- minathan TN. Comparative Evaluation of Heat-Polymerized and Auto-Polymerized Soft Liners with Regard to Transverse Bond Strength, Peel Bond Strength and Water Sorption: An in vitro Study. Int J Prosthodont Restor Dent 2014;4(3):61-67.


2021 ◽  
Vol 12 (5) ◽  
pp. 6863-6872

In this experimental study, the effects of Er,Cr:YSGG laser on the shear bond strength (SBS) of brackets bonded to two ceramic surfaces (Feldspathic and IPS Empress II) were compared to hydrofluoric (HF) acid etching. 60 ceramic discs were prepared, including two groups: Feldspathic and IPS Empress II surfaces. In each group, the following subgroups were prepared: 2W Er,Cr:YSGG laser, 2.5W Er,Cr:YSGG laser, and HF acid-etching. Ceramic primer and adhesive resin composite were applied and then light-cured to bond the ceramic cylinders to brackets. The samples were stored in distilled water for 24h and then, thermocycled. SBS testing was performed with a universal testing machine. Two-way ANOVA was used to compare SBS among subgroups (P<0.05). The highest SBS was seen in feldspathic surfaces with HF preparation (14.61±3.11MPa). There was a significant difference in SBS between different surface treatments except between the laser groups of IPS Empress II. Also, feldspathic surfaces had significantly higher SBS than IPS Empress II in all groups except HF. Conventional surface treatment provides much stronger adhesion than laser regardless of the ceramic type. Er,Cr:YSGG laser is effective on the SBS of the feldspathic ceramics, but not in IPS Empress II ceramics. So, laser treatment can be recommended as a favorable setting for treating feldspathic surfaces.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Konstantinos Pantos ◽  
Mara Simopoulou ◽  
Evangelos Maziotis ◽  
Anna Rapani ◽  
Sokratis Grigoriadis ◽  
...  

AbstractThe chronic nature of Chronic Endometritis (CE) along with the challenging management and infertility entailed, call for cutting-edge therapeutic approaches. This study introduces the novel treatment of intrauterine antibiotic infusion (IAI) combined with oral antibiotic administration (OAA), and it assesses respective performance against the gold standard treatment of OAA. Data sourced herein reports on treatment efficiency and fertility restoration for both patients aiming to conceive naturally or via In Vitro fertilization. Eighty CE patients, 40 presenting with recurrent implantation failure, and 40 with recurrent pregnancy loss, were enrolled in the IVF and the natural conception arm respectively. Treatment was subjected to randomization. Effectively treated patients proceeded with either a single IVF cycle or were invited to conceive naturally over a 6-month period. Combination of IAI and OAA provided a statistically significant enhanced effectiveness treatment rate (RR 1.40; 95%CI 1.07–1.82; p = 0.01). No statistically significant difference was observed regarding the side-effects rate (RR 1.33; 95%CI 0.80–2.22; p = 0.52). No statistically significant difference was observed for either arm regarding live-birth rate. Following an intention-to-treat analysis, employment of IAI corresponds to improved clinical pregnancy rate-albeit not reaching statistical significance. In conclusion, complimentary implementation of IAI could provide a statistically significant enhanced clinical treatment outcome.


2015 ◽  
Vol 03 (02) ◽  
pp. 080-084
Author(s):  
Vijay Singh ◽  
Poonam Bogra ◽  
Saurabh Gupta ◽  
Navneet Kukreja ◽  
Neha Gupta

AbstractFracture resistance of endodontically treated teeth restored with post. Aims: This study aims to compare the fracture resistance of endodontically treated teeth restored with resin fiber and stainless steel post. Commercially available prefabricated resin fiber post(Dentsply Maillefer Easy Post), prefabricated stainless steel post(Coltene/Whaledent Parapost) were used. Methods and Material: Forty five maxillary central incisors were obturated and divided into 3 groups: Control Group (Group I) without any post (n = 15), Resin Fiber Post Group (Group II) (n = 15) and Stainless Steel Post Group (Group III) (n = 15). In all Groups except control group, post space was prepared; a post was cemented, and a core build-up was provided. All the specimens were subjected to compressive force under a universal testing machine until fracture. Statistical analysis used: The results were analyzed using the variable analysis test (ANOVA). Results: One-way analysis of variance revealed significant difference among test groups. The control group demonstrated highest fracture resistance (925.2183 N), followed by the resin fiber post group (486.7265 N) and stainless steel post group (423.539N). Conclusions: Teeth restored with resin fiber post showed higher fracture resistance values than prefabricated stainless steel post.


2018 ◽  
Vol 6 (9) ◽  
pp. 1707-1711
Author(s):  
Rami M. Atia ◽  
Nada Omar ◽  
Haidy Nabil ◽  
Yousra Aly

OBJECTIVE: The aim of this in vitro study was to assess the effect of obturation technique and cementation timings on the bonding of fibre-reinforced posts to the root canal walls. METHODS: Twenty extracted teeth were randomly allocated to two groups according to the obturation technique and cementation timing. Central incisors with single canals were used after being decoronated. Every extracted tooth of the {vertical compaction group} (VC) group (n = 10) had been obturated using the {E & Q plus obturation system} with posts cemented in the same day; The other (CO) conventional group (n = 10) teeth were obturated using the conventional lateral compaction technique and posts cemented after one week. “SF“ Fiber posts were used after bonding and cementation using Rely X ARC resin cement with all the endodontically treated teeth. The push-out test was performed in a universal testing machine. Data were analysed by 2 way analysis of variance with Statistical significance was set to 0.05. RESULTS: Heat softened gutta percha group showed more push out the bond strength of the bonded posts than the conventional obturation group (p < 0.05). In the middle region, there was no statistical significance between the two groups while there was significance in the coronal and apical thirds. CONCLUSION: The vertical compaction technique and early cementation improved the bond strength of the resin posts in comparison to the conventional obturation technique with late cementation.


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