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Clinical retention force development of double crowns
Stefan Bayer1, Helmut Stark, Lina Gölz
1Department of Prosthodontics, Preclinical Education and Dental Materials Science, Welschnonnenstr.17, 53111 Bonn, Germany. sbayer@uni-bonn.de
Clinical Oral Investigations
|March 2, 2011
Summary
Retentive forces of double crowns in dentures remain clinically stable for the first 18 months. Intraoral measurements show no significant changes, indicating reliable denture retention over time.
Area of Science:
- Dental prosthetics
- Biomaterials science
- Clinical dentistry
Background:
- Double crowns are utilized in combined fixed-removable prostheses.
- Assessing the long-term retentive forces of these attachments is crucial for clinical success.
Purpose of the Study:
- To investigate the intraoral retentive forces of double crowns over an 18-month period.
- To evaluate the clinical stability and potential wear effects on retention.
Main Methods:
- Intraoral measurement of retentive forces on 84 double crowns in 25 patients.
- Measurements taken at baseline, 6 months, and 18 months post-insertion.
- Analysis of median values and statistical comparison between time points.
Main Results:
- Median retentive forces were 4.7 N (baseline), 5.2 N (6 months), and 3.7 N (18 months).
- No statistically significant difference in retention force was observed after 6 months.
- A slight, non-statistically significant decrease in retention force was noted by 18 months.
Conclusions:
- Intraoral retentive forces of double crowns remain clinically stable within the first 1.5 years.
- Wear does not significantly impact retentive forces within the initial 18 months.
- Double crown retention is expected to be sufficient for denture stability during this period.
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