An In Vivo 24-Month Study to Compare Crestal Bone Loss and Pocket Depth of Platform-Switched Implants Placed in Maxillary Anterior and Mandibular Posterior Regions.

Abstract

To analyze and compare crestal bone loss and pocket depth around platform-switched implants placed at two intraoral locations. Eighty platform-switched implants, 40 in the maxillary anterior region (group - ANT) and 40 in the mandibular posterior region (group - POST), were placed in healthy men aged between 25 and 45 years, and restored following two-stage surgical and progressive loading protocols. Digital radiographs for crestal bone level assessment and pocket depths on facial, mesial, distal, and palatal/lingual sites around the implant were recorded at definitive restoration cementation (baseline) and 6-month follow-up. Difference in pre- and post-periodontal pocket depths and crestal bone loss levels were measured and analyzed statistically using SPSS v.16.0, applying the Mann-Whitney test (p < 0.05 considered significant). Mean bone loss was significantly higher in group ANT (1.2 ± 0.3 mm) than in group POST (0.7 ± 0.02 mm). Palatal pocket depth increase was significantly greater in the ANT group (p = 0.01), and distal pocket depth increase was significantly greater for the POST group (p = 0.002). The amount of bone loss noted in the maxillary anterior region compared to the mandibular posterior region was significantly more. This could possibly be because of greater vertical cantilever and offset loads in the anterior compared to the posterior region. Significantly greater pocket depth in mandibular posterior distal and maxillary anterior palatal regions could be related to oral hygiene maintenance issues.