Evaluation of implant primary stability using different drilling protocols: an in vitro study

Area of Science:

• Biomaterials Science
• Dental Implantology
• Bone Biomechanics

Background:

• Maxillary implant surgery in low-density D3-D4 bone presents challenges for achieving primary stability.
• Standard drilling protocols may require modification, such as omitting countersinks, based on clinical judgment.
• Limited in vitro data exists on the impact of surgical modifications on implant stability in low-density bone.

Purpose of the Study:

• To investigate the biomechanical effects of different drilling techniques on dental implant primary stability.
• To quantify the impact of undersized drilling, standard drilling, and countersinking on implant stability in D3-D4 bone models.

Main Methods:

• In vitro study using bovine bone specimens simulating D3-D4 bone quality.
• Placement of 21 implants using three protocols: undersized drilling, standard drilling, and countersinking (n=7 each).
• Primary stability assessed by insertion torque (IT), removal torque (RT), and resonance frequency analysis (RFA).

Main Results:

• Undersized and standard drilling yielded significantly higher IT and RT compared to countersinking (p<0.05).
• Resonance frequency analysis showed highest stability in the undersized group (ISQ 77.0), followed by standard (75.0) and countersinking (69.0).
• Undersized drilling demonstrated a statistically significant improvement in stability over countersinking (p<0.05).

Conclusions:

• Countersinking significantly reduces primary implant stability in low-density bone models (D3-D4).
• Undersized drilling is more effective in enhancing implant stability in low-density bone conditions.
• Findings suggest modifying drilling protocols can optimize implant outcomes in compromised bone.