Bio-HPP vs Cast Co-cr as Implant Framework

Short Term Comparative Evaluation of Bio-HPP and Cast Cobalt-chromium as a Framework for Implant-supported Prostheses: A Split-mouth Clinical Randomized Study

The purpose of this study was to assess the effect of Bio-Hpp versus Co-Cr custom abutments in fixed-detachable implant-supported mandibular partial dentures clinically and radiographically in Class I Kennedy classification (split-mouth study)

Participants with bilateral partial edentulism in the posterior mandible received two implants at the positions of the second premolar and second molar on both sides; one side was restored with BioHpp based screw-retained FDP (test group) and the other side was restored with Co-Cr based screw-retained FDP (control group). All patients were clinically examined at the time of prosthesis insertion, and 6,12 months later for fracture of implant or framework, fracture, or looseness of the screw, veneer chipping, and fractures, modified bleeding index, modified plaque index, peri-implant probing depth, as well as radiographically for marginal bone loss

Inclusion Criteria:

• Mandibular posterior edentulous with the first premolar as the last standing abutment tooth bilaterally.

  • All patients were edentulous for at least 6 months from the last extraction.
  • The bone height of the alveolar ridge was not less than 12 mm above the inferior alveolar canal and the buccolingual width of the alveolar ridge at the prospective implant site was not less than 6 mm.
  • The opposing arch was almost dentulous, and any missing teeth were restored using a fixed partial denture.
  • Adequate interarch space at least 5mm between the opposing dentition and the mandibular edentulous space.
  • Remaining teeth were in good periodontal condition.
  • Maintaining good oral hygiene and were ready to cooperate throughout the study.

Exclusion Criteria:

• Patients with active infection or inflammation or flabby tissue in the areas intended for implant placement.

  • Those patients with systemic diseases that may influence soft or hard tissue healing.
  • Patients with a history of radiation therapy in the head and neck region.
  • Neurological or psychiatric handicap patients that could interfere with good oral hygiene.
  • Heavy smokers and drug abusers.
  • Patients with severe clenching or bruxism.