Advanced Subtractive Manufacturing, Micromilling, and Laser Micromachinery in Dentistry: Current Applications, Limitations, and Future Perspectives

Objectives: To comprehensively overview the computer-aided design/computer-aided manufacturing (CAD/CAM) technology, focusing primarily on subtractive manufacturing or Computer Numerical Control (CNC) milling, with special attention to advancements and future requirements. Materials and Methods: A comprehensive web search was conducted in April 2024 across PubMed, Scopus, and Web of Science databases. The inclusion criteria focused on English peer-reviewed studies addressing technological advancements, grinding modes, and limitations. However, non-English articles, case reports, opinion pieces, and studies without substantial technological focus were excluded. Identified studies underwent a two-stage screening process, followed by thematic categorization into three areas: historical development, classification of milling machines, and applications in dentistry. Results: CNC milling technology remains the predominant production method to this day, while interest in additive manufacturing continues to grow. The 5-axis milling machines are the most advanced in dentistry; however, higher axes of milling have yet to be introduced. Recent advancements have seen hybridization, incorporating integrated lathes or 3D printing, as explored by manufacturing companies and researchers. Conclusion: Understanding the subtractive manufacturing pros and cons is crucial to addressing the challenges associated with material waste, time-intensive production, and accuracy concerns. Additive manufacturing or lathe technology with 5-axis milling machines creates new opportunities for beneficial hybridization. Furthermore, the compact and steady design of milling machines, combined with the integration of AI and innovative manufacturing techniques, has the potential to significantly enhance the efficiency, speed, and quality of dental parts production. This promotes remote monitoring, simplifies CAD/CAM processing steps, ensures ergonomic posture, and facilitates a fluent workflow.