A Comparative Three Year Study of
Two Vs One-Stage Screw Type Titanium Implants in Human Clinical Trials


Placement of 382 screw-type titanium implants using conventional two-stage technique were compared with 232 identical implant placed one-stage with a pre-attached 3 mm titanium hexagonal abutment. The presence of the 3 mm hexagonal abutment specifically designed to protruded above the oral mucosal or gingiva during the three to six month healing period, no second stage surgery was required. A total of 109 consecutive patients over a period of 36 months were evaluated.
Clinical parameters such as pocket depth, gingival health, attached epithelium, plaque index, bone loss, calculus index, mobility & pain were evaluated in both techniques. Age, gender, implant length, jaw locations, bone density or type were also analyzed.
Three years life table (Kaplan-Meier) analysis indicated no significant difference in survival between the two-stage (93.3%) and the one-stage (89.6%) P>0.05.

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supported in part by National Research Council of Canada #25636U