Practice-Based Study on CAD/CAM Inlays, Onlays, and Crowns: Longevity and Risks

Area of Science:

• Dental Materials Science
• Clinical Dentistry
• Biomaterials Engineering

Background:

• All-ceramic restorations are widely used for dental rehabilitation.
• Understanding factors influencing their long-term success is crucial for clinical practice.
• Previous studies have focused on specific materials or failure modes, necessitating a comprehensive analysis.

Purpose of the Study:

• To identify predictors of failure and success for all-ceramic inlays, onlays, and crowns.
• To analyze tooth-, technique-, and material-level factors associated with restoration longevity.
• To evaluate the long-term performance of computer-aided design/computer-aided manufacturing (CAD/CAM) all-ceramic restorations.

Main Methods:

• Prospective, multicenter, practice-based cohort study including 17,725 restorations from 12,468 patients.
• Data collected from 1994 to 2023 by 303 dentists.
• Multilevel Cox proportional hazards models used to analyze time to failure or success, with follow-up up to 25 years.

Main Results:

• The annual failure rate after 5 years was 2.7%, with main failure types being ceramic fracture, endodontic complications, and tooth fracture.
• Endodontic treatment (HR 1.6), positive papilla bleeding index (HR 1.2), and EVA instrument use (HR 1.8) significantly increased failure rates.
• Zirconia (ZrO2) use significantly increased time until failure (HR 0.6).

Conclusions:

• High success rates for CAD/CAM all-ceramic restorations were observed up to 25 years.
• Tooth, technique, and material factors significantly influenced failure rates after 8 years.
• Endodontic health and material choice are critical for long-term all-ceramic restoration survival.