Cortical bone strains around straight and angulated immediate orthodontic microimplants: a pilot study

Area of Science:

• Orthodontics
• Biomaterials Science
• Biomechanics

Background:

• Orthodontic microimplants are crucial for anchorage.
• Understanding strain distribution around implants is vital for predicting stability and success.
• Primary stability is influenced by various factors, including placement torque and bone characteristics.

Purpose of the Study:

• To quantify strains around orthodontic implants during torque tightening and orthodontic loading.
• To evaluate the relationship between placement torque, implant angulation, and resulting bone strain.
• To assess correlations between factors influencing the primary stability of orthodontic microimplants.

Main Methods:

• Bovine iliac crest blocks were used with CT assessment for implant placement.
• Strain gauges were attached to adjacent bone, measuring strains during torque application and orthodontic force.
• Data acquisition system recorded strain measurements during simulated clinical procedures.

Main Results:

• Higher torque was required for vertically placed implants (12.16 N.cm) compared to angulated ones (9.31 N.cm).
• Bone strain amplitudes were comparable between straight and angulated implant placements.
• Strains during torque tightening were significantly higher than during subsequent orthodontic loading.

Conclusions:

• Both vertically aligned and angulated orthodontic microimplants exhibit low strain amplitudes.
• The findings suggest that angulated placement does not compromise implant stability under initial loading conditions.
• Further research is needed to fully elucidate the multifactorial nature of primary implant stability.