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Published on: May 31, 2017
Effect of placement angle on the stability of loaded titanium microscrews in beagle jaws
Zhenrui Xu1, Yeke Wu, Lixing Zhao
1State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China.
Objective:
To evaluate the effect of insertion angle on stability of loaded titanium microscrews in beagle jaws.
Materials And Methods:
Forty-eight microscrews were inserted at four different angles (30°, 50°, 70°, and 90°) into the intraradicular zones of the mandibular first molars and third premolars of 12 beagles and immediately loaded with a force of 2 N for 8 weeks. Microcomputed tomography (micro-CT) and biomechanical pull-out tests were used to assess osseointegration of the interface.
Results:
All micro-CT parameters and maximum pull-out force (FMAX) of the microscrews were affected by insertion angles of microscrews. Higher micro-CT parameters and FMAX were seen for implants inserted at angles between 50° and 70° (P < .05). Excessive oblique and vertical insertion angles resulted in reduced stability (P < .05).
Conclusion:
An insertion angle of 50° to 70° is more favorable than excessive oblique or vertical angles to achieve stability of microscrews.
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