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Survival time comparison between Hawley and clear overlay retainers: a randomized trial
1Department of Orthodontics, State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, People's Republic of China.
Journal of Dental Research
|July 21, 2011
Summary
This study found no significant difference in survival time between Hawley retainers (HR) and clear overlay retainers (COR) over one year. Clinicians should reinforce retainer bases and avoid excessive buccal root torque.
Area of Science:
- Orthodontics
- Dental Materials Science
Background:
- Retainers are crucial for maintaining orthodontic treatment outcomes.
- Hawley retainers (HR) and clear overlay retainers (COR) are common post-orthodontic devices.
- Understanding retainer durability and failure modes is essential for clinical practice.
Purpose of the Study:
- To compare the one-year survival time of Hawley retainers (HR) and clear overlay retainers (COR).
- To identify risk factors associated with retainer breakage.
- To provide evidence-based recommendations for retainer selection and management.
Main Methods:
- A randomized controlled clinical trial involving 120 adolescent patients.
- Patients were assigned to receive either HR or COR.
- Survival analysis was employed to assess retainer durability over a one-year follow-up period, with detailed recording of breakage events.
Main Results:
- No statistically significant differences in survival times were found between HR and COR for either maxillary (p = 0.254) or mandibular (p = 0.188) retainers.
- Both retainer types exhibited fracture tendencies, but the specific locations of breakage differed.
- Analysis identified specific risk factors related to retainer fracture.
Conclusions:
- The choice between HR and COR may not be dictated by survival rates alone.
- Clinicians should consider reinforcing retainer base plates.
- Avoiding excessive buccal root torque is recommended to minimize retainer fractures.
