Effect of microthread on the maintenance of marginal bone level: a 3-year prospective study

OBJECTIVES: The purpose of the present study was to evaluate the long-term effect of the microthread on the maintenance of marginal bone level. MATERIAL AND METHODS: Seventeen patients were selected and two types of Astra Tech implants were installed, with the Microthread on the coronal portion of the fixture [Astra Tech Single Tooth Implant (ST)] or without the Microthread [Astra Tech TiOblast Implant (TB)]. ST and TB were installed adjacent to each other within the same partially edentulous sites and marginal bone loss was evaluated by radiographic image. The marginal bone-level alteration of the each fixture after prosthesis insertion was analyzed. RESULTS: The marginal bone loss of ST and TB differed significantly during the observation period (P<0.01). Marginal bone levels of both ST and TB were stabilized after 1 year of lading. CONCLUSIONS: The Microthread might have an effect in maintaining the marginal bone loss against loading.