Mini implants osseointegration, molar intrusion and root resorption in Sinclair minipigs

Area of Science:

• Orthodontics
• Biomaterials Science
• Dental Implantology

Background:

• Mini implants are utilized for passive intraoral anchorage, primarily evaluated in clinical trials.
• Understanding loading protocols is crucial for optimizing mini implant performance and patient outcomes.

Purpose of the Study:

• To experimentally evaluate immediate versus delayed loading protocols for mini implants.
• To assess the impact of loading on bone remodeling, implant stability, dental intrusion, and root resorption.

Main Methods:

• 40 mini implants were placed in 5 minipigs, with lingual buttons and nitinol coil springs applying 150g force.
• Morphological analysis included dental movement, implant stability, new bone formation, and microscopic examination of the bone-implant interface and root modifications.

Main Results:

• Mini implant success rate exceeded 98%, with immediate loading showing higher success.
• Immediate loading promoted significant osseointegration and intrusive dental movement, especially in second premolars.
• Radiological and histological studies revealed minimal root resorption despite intrusive movement and bone remodeling.

Conclusions:

• Immediate loading of smooth mini implants in minipigs is effective for achieving intrusive dental movement.
• This protocol stimulates bone growth and osseointegration with a low risk of root resorption.
• The findings support immediate loading as a viable strategy in orthodontic anchorage.