Aim: This study was conducted to compare the effect of ball and socket attachment and GPS attachment in implant retained mandibular overdenture cases regarding changes in: crestal bone height and density surrounding implants, electromyographic activity of temporalis and masseter muscles and occlusal biting force. Materials and Methods: Following two stage surgical protocol twelve completely edentulous patients received two implants placed bilaterally in the canine region (24 implants) to retain mandibular overdenture. Four months following the surgery patients were randomly divided into two equal groups; Group-I received ball and socket attachment while Group-II received GPS attachment upon which mandibular overdentures were retained. Once patients were comfortable to the prosthesis, they were placed on zero, three, six and twelve month follow-up period to measure: - Crestal bone height and density surrounding the implants using cone beam computed tomography. - Muscle activity of masseter and temporalis muscle using electromygraphic device. -Occlusal biting force using occlusal force-meter. Measurements were taken then the results were statistically analyzed. Results: Both attachment designs showed crestal bone resorption and increase in bone density during all intervals of follow-up period however, there was statistically significant difference between the two designs in favour of GPS attachment which showed less crestal bone resorption but, there was statistically none significant difference between them regarding the increase in bone density. By time, the muscle activity decreased in both attachment designs with statistically none significant difference between them during all intervals of follow-up period. The occlusal biting force increased in both attachment designs with statistically significant difference between them in favour of GPS attachment which showed more increase during all intervals of follow-up period. Conclusion: GPS attachment is less destructive to crestal bone surrounding the implants and has higher biting force than ball and socket attachment however, there is no difference between the two attachments in terms of muscle activity of masseter and temporalis muscles.
Rizk, Fardos N., "Effect of Two Different Attachments on the Supporting Structures and Masticatory Capacity of Implant Retained Mandibular Overdenture" (2014). Dentistry. 97.