A tapered variable-thread design implant with a 3.0 mm diameter (NobelActive®) placed in the anterior region

Objectives: To retrospectively evaluate a novel narrow diameter implant, (NobelActive, Nobel Biocare, Göteborg, Sweden) with a 3.0 mm diameter that has been developed for safe and reliable implant placement in areas with limited space. The 3.0 mm implant is intended for replacement of single unit maxillary lateral incisors as well as single unit lateral and central mandibular incisors. Methods: Six centers participated in the retrospective study. Twenty-four patients (11 females and 13 males) with a mean age of 31.9 years (range: 18 to 75 years) receiving a total of 29 implants between November 2010 and October 2011 were included in this analysis with a minimum follow-up of 1 year. Implants were placed in healed sites, extraction sites or in sites exhibiting congenitally missing teeth. Implants were inserted either with an open fl ap or a fl apless surgical protocol. All types of loading protocols were applied (i.e. immediate, early or conventional loading). When necessary, bone grafting was performed. Implants were restored according to the manufacturer's guidelines. At routine follow-up, the implants were inspected clinically according to each clinic's standard practice. For some centers this included Jemt's papilla index and bleeding on probing (BOP). Hygiene level was assessed as: excellent, good, acceptable or poor. Results: One implant was lost due to trauma after 2 months the remaining 28 implants were followed for 12 to 24 months (mean 15.1). One additional complication, a broken abutment screw, was noted. 21 implants were placed in the maxilla for replacement of the maxillary lateral incisors and 8 implants were inserted in the mandibular incisor region. 6 implants were placed in extraction sites, 6 in healed sites and 17 replaced congenitally missing teeth. 9 implants were loaded immediately (within 48 h), 8 were loaded after 48 h but prior to 3 months, and 9 were loaded after a minimum waiting period of 3 months. 8 implants were placed using flapless surgery and 21 using a flap. For 15 implants a 1-stage surgical protocol was chosen and for 11 implants a 2-stage protocol was used. At follow-up, papilla index was assessed in 21 implants. One implant showed an index of 1, 7 implants of 2, 12 an index of 3 and 1 implant an index of 4. BOP was assessed in 14 implants, all showing no signs of bleeding. Conclusion: Within the limitations of this retrospective study, the results on implant survival and soft tissue analyses with this novel 3.0 mm diameter tapered variable-thread design implant (NobelActive) seem to indicate that this implant is a viable and safe treatment option for subjects in need of an implant in anterior areas with limited space or for the treatment of congenitally missing teeth areas. Additionally, soft tissue evaluation indicates that the implant supports stable tissue. Parole chiave: anterior region, incisors, congenitally missing, single unit, single crown, survival, soft tissue