Combination of straight and tilted implants for supporting screw-retained dental prostheses in atrophic posterior maxillae: A 2-year prospective study

J Dent. 2017 Aug:63:85-93. doi: 10.1016/j.jdent.2017.05.022. Epub 2017 Jun 3.

Abstract

Objectives: To evaluate the two-year survival rate (SR) and marginal bone loss (MBL) of fixed dental prostheses (FDPs) supported by straight (S) and tilted (T) implants under the influence of diverse study variables.

Methods: A prospective investigation comprising 21 patients provided with a total of 27 maxillary screw-retained restorations fixed to 70 dental implants was developed. Two groups of implants were considered depending on their inclination with respect to the occlusal plane: Group 1 (S, n=37): straight/axial implants and Group 2 (T, n=33): tilted/angled fixations. Each FDP was supported by a combination of S and T implants. SR and MBL were assessed at the time of loading and two years after surgery. Patient-, surgical- and/or rehabilitation-related information was gathered. Data were statistically analysed at the α=0.05 significance level.

Results: After 24 months, a 100% SR was achieved and the MBL of S and T implants were statistically similar. T implants located in the molar region showed lower MBL than did those replacing premolars (p=0.031).

Conclusions: Upright and angled fixations inserted at posterior maxillary areas resulted in comparable survival rates and peri-implant MBL after two years. The marginal bone resorption around tilted implants depended on their location.

Clinical significance: Screw-retained restorations fixed to straight and tilted implants seem to be a safe treatment option in posterior atrophic maxillae.

Keywords: Angled implants; Atrophic maxilla; Axial implants; Fixed dental prostheses (FDPs); Straight implants; Tilted implants.

MeSH terms

  • Adult
  • Aged
  • Alveolar Bone Loss
  • Bicuspid
  • Bone Screws
  • Dental Abutments
  • Dental Implantation, Endosseous / methods
  • Dental Implants
  • Dental Prosthesis Design*
  • Dental Prosthesis Retention*
  • Dental Prosthesis, Implant-Supported*
  • Dental Restoration Failure / statistics & numerical data*
  • Dental Stress Analysis
  • Denture, Partial
  • Female
  • Humans
  • Immediate Dental Implant Loading*
  • Male
  • Maxilla / surgery*
  • Maxillary Sinus
  • Middle Aged
  • Molar
  • Prospective Studies
  • Spain

Substances

  • Dental Implants