Freehand vs. depth-gauge rotary instruments for veneer preparation: A controlled randomized simulator study.

Area of Science:

• Dental Materials Science
• Restorative Dentistry
• Clinical Dentistry

Background:

• Accurate preparation depth is crucial for successful dental veneer placement.
• Inexperienced operators may struggle to achieve consistent preparation depths.
• Depth-gauge burs are designed to aid in controlling preparation depth.

Purpose of the Study:

• To evaluate the influence of depth-gauge burs on veneer preparation depth.
• To assess the ability of inexperienced dental students to perform adequate veneer preparations.
• To compare the efficacy of different depth-gauge systems against freehand preparation.

Main Methods:

• A randomized, controlled, single-blinded trial involving 20 dental students.
• Comparison of three instrument groups: Laminate Veneer System (LVS), Keramik-Veneers. de (KVD), and Freehand (FH).
• Preparation of acrylic resin teeth in patient simulators, with measurements taken using a laser triangulation coordinate-measuring machine.

Main Results:

• Depth-gauge burs (LVS and KVD) significantly improved preparation depth control compared to the Freehand group (P < 0.001).
• No significant difference between LVS and KVD groups, though KVD showed smaller maximum preparation depths.
• Mandibular incisors had lower preparation depths with smaller variations.

Conclusions:

• Specialized depth-gauge burs enhance control over preparation depth in initial veneer preparations.
• Tapered instruments, like those in depth-gauge systems, reduce the occurrence of extreme preparation depths.
• Inexperienced operators demonstrated proficient veneer preparation skills when using depth-gauge burs.