In‐vitro evaluation of the tolerance of surgical instruments in templates for computer‐assisted guided implantology produced by 3‐D printing

Abstract

OBJECTIVE: The aim of this in-vitro study was to compare the tolerance of surgical instruments in surgical guides produced by 3-D printing, without metal sleeves to a surgical guide with conventional metal sleeves from two different manufacturers. MATERIALS AND METHODS: Lateral movements of drill tips caused by tolerance between the sleeve and drill key and between the drill key and the drill were recorded after application of a standardized force to the surgical instruments. Four groups were tested: Control 1 (C1): metal sleeve from commercially available surgical system 1; Test 1 (T1): 3-D-printed sleeve for surgical system 1; Control 2 (C2): metal sleeve from commercially available surgical system 2. Test 2 (T2): 3-D-printed sleeve for surgical system 2. RESULTS: The mean total lateral movement was 0.75 mm (0.5-1.04 mm) in the C1 group and 0.91 mm (0.54-1.34 mm) in the C2 group. The mean amount of movement from tolerance between sleeve and drill-guiding key was 0.31 mm (range 0.22-0.41 mm) in C1 and 0.42 mm (range 0.29-0.56 mm) in C2. This lateral movement was in mean reduced by 0.24 mm (32%) in T1 and by 0.39 mm (43%) in T2 group. This reduction was statistically significant in both groups (P < 0.001). CONCLUSION: The tolerance of surgical instruments and the lateral movements of the drills were significantly reduced by the use of 3-D printing with reduced sleeve diameter. This reduction could improve the overall accuracy in computer-assisted template-guided implant dentistry. The lateral movement of the drill can be further reduced by using a shorter drill and a higher drill key. This can be considered during implant planning and CAD/CAM of surgical guides. AbstractObjective: The aim of this in-vitro study was to compare the tolerance of surgical instruments in surgical guides produced by 3D printing, without metal sleeves to a surgical guide with conventional metal sleeves from two different manufacturers. Materials and methods:Lateral movements of drill tips caused by tolerance between the sleeve and drill key and between the drill key and the drill were recorded after application of a standardized force to the surgical instruments. Four groups were tested: Control 1 (C1):Metal sleeve from commercially available surgical system 1; Test 1 (T1): 3D-printed sleeve for surgical system 1; Control 2 (C2): Metal sleeve from commercially available surgical system 2. Test 2 (T2): 3D-printed sleeve for surgical system 2. Results:The mean total lateral movement was 0.75mm (0.5 to 1.04mm) in the C1 group and 0.91mm (0.54 to 1.34mm) in the C2 group. The mean amount of movement from tolerance between sleeve and drill-guiding key was 0.31mm (range 0.22 to 0.41mm) in C1 and 0.42mm (range 0.29 to 0.56mm) in C2. This lateral movement was in mean reduced by 0.24mm (32%) in T1 and by 0.39mm (43%) in T2 group. This reduction was statistically significant in both groups (p<0.001). Conclusion:The tolerance of surgical instruments and the lateral movements of the drills were significantly reduced by the use of 3D prin...

Accuracy of Computer-Assisted Template-Based Implant Placement Using Two Different Surgical Templates Designed with or without Metallic Sleeves: A Randomized Controlled Trial

“…Surgical templates without metallic sleeves can be easily designed and customized using dedicated software. This allows us to eliminate the metal tubes, and possibility to reduce the tolerance between the printed sleeves and the drill-guiding keys [13]. …”

“…This protocol includes CAD and the use of 3D printing for surgical guide production without the use of any metal sleeves and with a more intimate contact between the guide and the drill-guiding drill key [13]. …”

The influence of guided sleeve height, drilling distance, and drilling key length on the accuracy of static Computer‐Assisted Implant Surgery

“…The findings are consistent with long established engineering principles that an increase in drilling length is associated with an increase in lateral vibration and chattering. As an example, in a previous study Schneider et al demonstrated that drill lateral movement, resulting from tolerance of surgical instruments can be reduced by decreasing the drill length and increasing the key height above the sleeve. Whether this surgical tolerance and lateral movement would translate into a significant deviation in a clinical scenario has not been established.…”

“…As the popularity of the sCAIS increases, the responsible introduction of it's broad application requires a knowledge of common variables and decision‐making points during treatment planning and execution. Errors during data acquisition, data transfer, data processing, treatment planning, guide design and production, as well as surgical execution might all contribute to increased deviations from the virtually planned implant position . The variables encountered during the treatment‐planning step by itself are numerous.…”

Accuracy of Image‐Fusion Stereolithographic Guides: Mapping CT Data with Three‐Dimensional Optical Surface Scanning

“…(2) Incorrect fit of the surgical template on the remaining teeth or surgical transfer: The correct fit may be guaranteed by choosing a small offset‐spacer in the stereolithographic production process and continuous surveillance during surgery. Perfect adaption of the planned implant and the corresponding sleeve, burr, drill handle, drill cylinder, and other material is recommended to minimize errors during the surgical phase …”