COMPARATIVE STUDY BETWEEN TWO DIFFERENT TYPES OF ATTACHMENTS RETAINED IMPLANT MANDIBULAR OVER DENTUREON ON THE ANTERIOR MAXILLARY BONE RESORPTION

This study was conducted to evaluate and compare the effect of using two different
types of attachments (Locator and ball); to retain implants mandibular over denture on the
anterior maxillary bone resorption.
Material and methods: Fourteen completely edentulous male patients with problematic existing
mandibular dentures , received two implants in the canine region of the mandible. New maxillary complete dentures and mandibular overdentures were fabricated for all patients, following conventional clinical and laboratory techniques. Patients were divided randomly by closed envelops into two groups; Group I: Patients received implant retained overdenture by locator attachment, while Group II : patients received implant retained overdenture by ball attachment, four months after implant placement. Traced rotational tomograms were used for measurements of maxillary alveolar bone loss. The proportional value between bone areas and reference areas was expressed as a ratio R. Change in R for all patients were evaluated immediately before insertion overdenture (T0), and after two years (T2) later, and calculated for anterior maxillary area.
Results: During the two years; the follow up period showed a significant decreasing change in R in the anterior maxillary area. group II (ball attachment) showed a significant change in R more anterior maxillary ridge resorption than group I (locator attachment) (P = 0.011).
Conclusion : Within the limitation of this study and consideration of the small sample size,
it could be concluded that; Ball attachments for implant retained mandibular overdentures are
associated with more maxillary ridge resorption than locator attachments.