fa عمومى General پژوهشي Research <span style="font-size:11pt"><span style="line-height:normal"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:9.0pt"><span cambria="" style="font-family:">Objectives:</span></span></b><span style="font-size:9.0pt"><span cambria="" style="font-family:"> In most cases, the repair of existing dental restorations is preferred to changing the whole restoration. We designed a study to evaluate the effect of elective bonding systems on the result of bulk-fill composite repairs, which seems to be essential.</span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:9.0pt"><span cambria="" style="font-family:">Materials and methods:</span></span></b><span style="font-size:9.0pt"><span cambria="" style="font-family:"> Fifty-four samples of two types of bulk-fill composites: X-tra fil dental Bulk-fill composite and Tetric EvoCeram Bulk Fill composite, and three types of adhesive bonding 3M ESPE Scotchbond universal adhesive, G-Premio Bond, and ClearFil SE Bond, were used. The composite samples were placed in the mold, flattened by a glass slab, and then light-cured. The samples were stored in distilled water. Then they were thermocycled. The samples were divided into six groups (n = 9), and each composite was repaired with the same composite and different adhesive systems. The prepared samples were stored in distilled water once more. Then, the shear bond strength test was established using the universal test machine with a loading speed of 0.5 mm/min. The statistical data analysis was done with SPSS 17 software. (p<0.05)</span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:9.0pt"><span cambria="" style="font-family:">Results:</span></span></b><span style="font-size:9.0pt"><span cambria="" style="font-family:"> The results of the samples&#39; independent T-test showed that there is no statistically significant difference between the mean bond strength of the two types of Bulk-Fill composites (p-value > 0.05). In addition, the results of the one-way ANOVA test showed that there is no statistically significant difference between the mean bond strengths of the three types of adhesive systems (p-value > 0.05). </span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:9.0pt"><span cambria="" style="font-family:">Conclusions: </span></span></b><span style="font-size:9.0pt"><span cambria="" style="font-family:">In conclusion, the type of adhesive used has no significant effect on the repaired bulk-fill composite bond strength. Also, the type of bulk-fill composite has no significant effect on the bond strength.</span></span></span></span></span><br> &nbsp; Bulk-fill composite,Adhesive system,Bond strength,Repaired composite,Shear bond strength,Dental composite 1 6 http://intjmi.com/browse.php?a_code=A-10-1-690&slc_lang=fa&sid=1 Farnaz Talebabbasi 10031947532846008292 10031947532846008292 Yes Dentist, DDS, Dental and Periodontal Research Center, Dental Faculty, Tabriz University of Medical Sciences, Tabriz, Iran. Yashar Rezaei 10031947532846008293 10031947532846008293 No Assistant Professor, DDS, PhD, Dental and Periodontal Research Center, Dental Faculty, Tabriz University of Medical Sciences, Tabriz, Iran. Mehdi Daneshpooy 10031947532846008294 10031947532846008294 No Assistant Professor, DDS, MSc, Department of Operative Dentistry, Dental Faculty, Tabriz University of Medical Sciences, Tabriz, Iran Saeideh Ghasemi 10031947532846008295 10031947532846008295 No Dentist, DDS, Dental and Periodontal Research Center, Dental Faculty, Tabriz University of Medical Sciences, Tabriz, Iran.