High Crown to Implant Ratio as Stress Factor in Short Implants Therapy

Ledia Gaxho 1 , R. Isufi 1 , E. Petrela 2 , L. Abazaj 3  and K. Vera 3
  • 1 University of Medicine Tirana, Faculty of Dental Medicine Oral and Maxillo-Facial Surgery Department
  • 2 University of Medicine Tirana, Faculty of Medicine Public Health Department
  • 3 University of Medicine Tirana, Faculty of Dental Medicine Tirana, Albania


Background/Aim: The purpose of this study was to report the outcomes of crown to implant ratio (C/IR) measurements of single-tooth short implants. The specific aim of this study was to evaluate the effect of C/ IR on crestal bone loss, assessing the success of short locking-taper implants treatment.

Materials and Methods: The cohort study was based on a sample of 33 patients, 14 males and 19 females. They were treated by at least one hydroxyapatite-coated Bicon implant, restored with Integrated Abutment Crown cementless technique and porcelain fused to metal crowns. The study was conducted between 2010 and 2015. Patients were recalled after 1-year and 2-year period time. Periapical, panoramic radiographs and clinical photos were obtained. The outcome measures were C/IR, crestal bone levels and the success of short implants therapy.

Results: After all the measurements were done on the first day of implant loading and at last visit, the mean C/IR was 1.85 (range, 0.95 to 3.20) and the mean change in the mesio-distal crestal bone levels was -0.73mm. No significant correlation was found between the C/IR and the risk for crestal bone loss nor the risk for implant failure.

Conclusions: A high C/IR has no significant effect on crestal bone levels (r= -0.151, p= 0.230) and on failure of implant treatment (p= 0.631) after the insertion of single-tooth locking-taper and implant restorations.

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