Assessment of retention in cement retained implant supported crowns on surface modified abutments using circumferential grooves and airborne particle abrasion- An In-Vitro study

Abstract

Background: Implant restorations can be either screw-retained, cement retained, or a combination of both. Use of Provisional cement result high risk for loss of retention and de-cementation leads to accidental swallowing or worse, the aspiration of dental prosthesis^.

Aim: Evaluate the effect of circumferential grooves and Airborne Particle Abrasion on the retention of cemented cast copings on implant abutments.

Settings and Design; Hospital based observational study

Methods and materials: Fifty similarly-shaped implant abutments were divided into 5 groups as: without surface treatment,  with 1 groove,  2 grooves, 3 grooves and Airborne Particle Abrasion. Fifty identical NiCr cast copings were prepared to fit all abutments. The castings were cemented to each group of abutments with Glass ionomer cement (GC Gold labed 1). After thermal cycling and storage for 6 days in a water bath, retention tests were conducted with a tensile testing machine (Instron) (5 mm/min) and retentive forces were recorded. Data analysis were done using SPSS ver,17

Results and Conclusion: The mean retentive force of control group was 405.1880N and with one circumferential groove was 532.5620N(P <.001).The mean retentive force of two circumferential groove was 609.41N is approximately 50% greater than control group(P<.000), with three circumferential groove was 888.38N, which is more than 2 times than the retention force of the control group(P<.000). The Mean value of retentive force for the abutment surface treated with Air borne particle abrasion was 623.7120N. The retention increased substantially with increase in number of circumferential grooves. Surface modification by airborne-particle abrasion also increased the retention of implant cement-retained castings substantially.