ABSTRACT
Purpose: Purpose Of This Study Was To Photoelastic Stress Analysis Of Two Flexible Attachments Implant Supported Mandibular Overdentures With Different Implant Angulations (parallel Implants And Diverged Implants). Using Two Attachment Systems (locator And Sphero-flex)
Materials and Methods: Six Photo Elastic Epoxy Models Were Divided Into Two Groups. For First Group: While Duplication Of The Epoxy Models Two Implants Inserted Vertically (parallel To Each Other) For Second Group: While Duplication Of The Epoxy Models Two Implants Inserted Diverged Distally From Midline With 14 Degree Using Semicircular Protractor. After Epoxy Models Construction,the Locator Attachment Were Placed For The First Group Models While Spheroflex Attachment Were Placed For The Second Group Models. For Both Groups Models, Successive Loads (20,40,60,80,100) Newton Were Applied Using Photo Elastic Stress Analysis Machine By Using Metal Plate Fixed At The Lower First Molar Region Bilaterally Then Stresses Were Recorded And Analyzed. After The First Stage Of Loading, The Implant Attachments For Both Groups Were Interchanged Then The Second Stage Of Loading With Same Successive Loads (20,40,80,100) Were Applied Using The Same Protocol Of The First Stage. The Photo Elastic Stresses For The Two Loading Stages Were Recorded And Statistically Analyzed.
Results: No Statistic Significant Difference Between Two Groups Of Flexible Attachments (locator And Spheroflex) Was Observed When Successive Loads Were Applied On Parallel Implants While There Was Astatic Significant Difference (p? 5%) Between Two Groups When Successive Loads Were Applied On Angulated (diverged) Implants .
Conclusion: On Choosing The Flexible Attachment Comparing Locator And Sphero-flex In Case Of Parallel And Diverged Implants Assisted Over Dentures, The Locator Attachment Is More Preferred Regarding Peri Implant Stress Outcome.