Comparative carbon footprint analysis of semi-digital and fully digital implant-supported prosthesis fabrication processes

Amid growing climate concerns, dental practices have emerged as notable contributors to carbon emissions, particularly with the increasing of integrated digital technology. This study aims to evaluate the environemtnal and economic impacts of four different implant-supported prosthesis fabrication workflows. Data on resource and energy consumption were collected from two types of fabrication processes: semi-digital and fully digital, using either zirconia discs or hybrid ceramic blocks. The results revealed that: (1) the semi-digital process with a zirconia disc emitted 35.1 kgCO₂eq per unit, (2) the semi-digital process with a hybrid ceramic block emitted 32.8 kgCO₂eq per unit, (3) the fully digital process with a zirconia disc emitted 34.5 kgCO₂eq per unit, (4) the fully digital process with a hybrid ceramic block emitted 31.8 kgCO₂eq per unit, and (5) the major hotspots of emissions were electricity consumption for steam sterilization of dental equipment and the sintering furnace used in crown fabrication. Considering both environmental and economic aspects, the fully digital implant impression process using a zirconia disc offered the better balance of sustainability. It offers the lowest amount of production cost (26.0 USD/unit) and net emission cost (0.75 USD/kgCO₂eq) compared to other processes. These findings provide valuable insights for patients and healthcare policymakers in selecting an environmentally friendly implant impression process. Additionally, the integration of digital dentistry and strategic material selection should be prioritized in the development of future clinical guidelines and sustainability-oriented dental policies.