Do Angulated Implants Increase the Amount of Bone Loss Around Implants in the Anterior Maxilla?

Purpose: The aim of this study was to evaluate the relation between angulated implants and the bone loss around implants in the anterior maxilla. Materials and Methods: The subjects studied had a missing tooth in the anterior maxilla and a bone deficiency that required restoration with an angulated dental implant. After mounting the casts on the articulator, the amount of direction was measured with a facebow by calculating the difference between the mean buccopalatal angulation of the 2 adjacent natural teeth and the buccopalatal angulation of the implant abutment to the occlusal plane. Radiography was performed in each patient immediately after loading and repeated a minimum of 36 months after loading. Results: Fifty-eight subjects who received delayed-loading angulated implants were studied. The results showed that the mean implant angulation was 15.2 degrees and the mean bone resorption was 0.87 mm. Analysis of the data showed a significant correlation between implant follow-up time and bone loss. No correlation was seen between the implant angulation and bone loss. An assessment of predictive factors showed a relation between the implant type and bone loss. The follow-up time had a significant effect on bone loss. The implant angulation did not change bone resorption on the mesial and distal surfaces of the implants. Conclusions: The angulation of implants was not associated with an increased risk for bone loss, and angulated implants may be a satisfactory alternative to vertical implants to avoid grafting procedures. The type of implant may be an important factor that affects bone resorption, although follow-up time was the strongest predictive factor. (C) 2013 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 71:272-277, 2013