Simulated bone for dental implant in vitro testing: A systematic review

Area of Science:

• Biomaterials Science
• Dental Implantology
• Mechanical Engineering

Background:

• Laboratory testing of dental implants relies on simulated bone, but methodological variations may impact results.
• Clinical failure patterns of dental implants are complex and may not be fully replicated in current in-vitro models.

Purpose of the Study:

• To evaluate methodological factors in simulated bone fabrication for dental implant testing.
• To assess the relationship between these factors and reported clinical failure patterns.

Main Methods:

• A systematic literature search (PRISMA) identified in-vitro studies (2015 onwards) on mechanical testing of single-unit implants with simulated bone.
• Data on bone material characteristics, bone loss simulation, loading angulation, and implant connection type were extracted and analyzed.
• RoBDEMAT appraisal was used to assess study quality.

Main Results:

• Ninety-one studies were included, predominantly using single-layer resin bone analogs.
• Commonly simulated bone loss was 3 mm, and loading was applied at 30°.
• Frequent failure modes included screw loosening, screw fracture, abutment fracture, crown/veneer fracture, and implant fracture.
• Off-axis loading with crestal bone loss shifted failures towards implant fractures.

Conclusions:

• Laboratory-observed failure modes partially correlate with clinical observations.
• Simulated bone loss, stiffness, and loading angle significantly influence failure patterns in dental implant testing.
• Current standards (e.g., ISO 14801) require updates to better reflect clinical data and improve the relevance of in-vitro studies.