Medical Bone Screw Material Classification:
1. Titanium and Titanium alloy series (can be processed with nearly 20 different colors) (A grade material generally stock, AA grade material need to be mass customized)
2. Ultra high rust-proof and high wear-resistant stainless steel series (AA) (HRC54°±2°Section) (generally stock)
3. Ultra-high rust-resistant austenitic stainless steel (generally stock)
4. High wear-resistant PEEK, PPSU and other series of different colors can be customized (generally stock)
When a removable denture is worn, retainers to maintain the denture in location can be either customized made or "off-the-shelf" (stock) abutments. When custom retainers are used, four or extra implant fixtures are positioned and an impact of the implants is taken and a dental lab creates a custom steel bar with attachments to hold the denture in place. Significant retention can be created with more than one attachments and the use of semi-precision attachments (such as a small diameter pin that pushes via the denture and into the bar) which lets in for little or no movement in the denture, however, it remains removable. However, the same 4 implants angled in such a way to distribute occlusal forces may be able to safely keep a fixed denture in place with similar expenses and variety of procedures giving the denture wearer a constant solution.