نوع مقاله : مقالههای پژوهشی
نویسندگان
1 دستیار تخصصی، گروه اندودنتیکس، دانشکدهی دندانپزشکی، دانشگاه آزاد اسلامی واحد اصفهان (خوراسگان)، اصفهان، ایران.
2 استادیار، گروه پروتزهای دندانی، دانشکدهی دندانپزشکی، دانشگاه آزاد اسلامی واحد اصفهان (خوراسگان)، اصفهان، ایران.
3 دستیار تخصصی، گروه جراحی دهان، فک و صورت، دانشکدهی دندانپزشکی، دانشگاه آزاد اسلامی واحد اصفهان (خوراسگان)، اصفهان، ایران.
چکیده
عنوان مقاله [English]
نویسندگان [English]
Introduction: Abutment dimension is one of the most important factors affecting the retention of implant-supported restorations. Thick abutments have the advantages of providing a thicker outer body wall and more surface area for retention. This study aimed to determine the effect of abutment dimension on the retention of implant-supported restorations.
Materials & Methods: Forty implant analogs were mounted in auto-polymerizing acrylic resin blocks with the use of a surveyor in this in vitro study. Forty titanium abutments (7 and 5.5 mm in height, and 3.5 and 4.3 mm in width) were placed on each implant analog using 30-N.cm torque. The crowns were cemented with temporary cement. All the specimens were stored under 100% relative humidity at 37ºC for 48 h prior to testing. Each crown underwent a tensile force with increasing force in a universal testing machine at a crosshead speed of 0.5 cm/minute, and the tensile strength was recorded (N). The data were analyzed with two-way ANOVA using SPSS 23.
Results: An increase in abutment height significantly increased the tensile strength (p value = 0.03). An increase in the abutment width decreased the tensile strength, but it was not significant (p value = 0.41). There was a direct and significant correlation between the abutment height-to-width ratio and restoration retention (r = 0.343, p value = 0.01). There was a direct but poor correlation between the abutments total surface (abutment height*abutment diameter) and retention (r = 0.185, p value = 0.127).
Conclusion: Increased abutment height and height-to-width ratio had a more positive effect on retention than increased total surface area provided by increased width.
Key words: Abutment, Implant, Provisional cement, Restoration, Tensile strength.