Huda Mohammed Metwally Osman, Ahmed Gamal Ahmed Hassan Mohammed Sayed M. Hassan And Emad Mohammed Tolba Agamy,

ABSTRACT
Background: Surface Roughness Of The Denture Plays A Major Role In The Adhesion Of Microorganisms, It Is Affected Primarily By The Finishing And Polishing Techniques. The Aim Of This Study Was To Evaluate The Effect Of Two Finishing And Two Polishing Techniques On The Surface Roughness Of Thermoformed And Heat Activated Acrylic Resin Denture Base Materials And Their Effect On Candida Albicans Attachment. Materials And Method: 80 Samples (64?10?2.5mm) Were Prepared (40 Heat Activated Acrylic ?material A? And 40 Thermoformed Denture Base Materials ?material B?). The Samples Of Each Material Were Divided Into Two Main Groups According To The Finishing Method Group 1 And 2. Group 1 Finished By Tungsten Carbide Bur, White AL2O3, Green Carborandum Stone And Sand Paper Of Grit Size More Than 120. Group 2 Finished By Tungsten Carbide Cutter And Acrylic Polisher (coarse Green, Medium Grey, Fine Red). Each Group Was Divided Into Two Subgroups According To The Polishing Method. Each Subgroup Contained 10 Samples, Subgroups (a) For Both Materials Were Polished By Fine Pumice With Wet Rag Wheel And 1500 Rpm Motor Speed For 2 Minutes. While Sub Groups B For Both Materials Were Polished By Abraso Star Glaze Paste, Brown Tripoli Compound And Leather Buff. The Mean Surface Roughness Values (Ra) Were Gained For Each Sample Before And After Finish And Polish. The Samples (before And After Finish And Polish) Were Incubated In Media Containing Suspension Of Candida Albicans Cell (conc. Of 1.5*106cell/ml) For 24h At 370C.

Results: Heat Activated Acrylic Samples That Were Finished By Technique 2 And Polished By Technique (b) Recorded Lower Roughness Mean Value Than Thermoformed Acrylic, However These Differences Are Statistically Non-significant (P>0.05) As Indicated By Unpaired T-test. Conclusion: Using Techniques Of Finishing And Polishing (recommended For Thermoformed Acrylic) For Thermoformed And Heat Activated Acrylic Resin Will Yield Smoother Surface More Than Using Finishing And Polishing Techniques (recommended For Heat Activated Acrylic Resin). This Method Has Less Candidal Attachment For Both Materials.