Defense Date


Document Type


Degree Name

Master of Science



First Advisor

Eser Tufekci


Enamel demineralization in the form of white spot lesions (WSLs) around fixed orthodontic appliances is a persistent problem in patients with poor oral hygiene.These lesions can form rapidly within 4 weeks of bracket placement.The purpose of this in-vitro study was to investigate the fluoride recharging capability ofa commercially available orthodontic primer used to minimize the development of WSLs in patients. The three groups tested were: OpalSeal (n=20, Ultradent, South Jordan, UT), ProSeal (n=20, Reliance, Itasca, IL) and Transbond XT (control, n=10, 3M Unitek, Monrovia, CA). The samples(5mmin diameter x 1mm in thickness) weresuspended individually in vials filled with 10mL of deionized water usinga fishing line. The baseline fluoride ion release from all of the samples was measured after two weeks of changing the solution every other day. The samples were then randomly divided into two groups, toothbrush or gel. The samples in the toothbrush group were brushed for one minute every day for 7d, with fluoride containing toothpaste (Colgate-Palmolive Company, New York, NY) and placed in a new solution after each brushing. After 7d of brushing the fluoride ion release was measured. The samples in the gel group were immersed in 10mL of acidulated phosphoric fluoride gel (APF) for one minute, following manufacturer’s instructions, and then placed in a new vial with 10mL of deionized water. At the end of 24hrs fluoride ion release measurementswere made and the samples were placed individually in a new solution. The solution was changed weekly in the gel group over six weeks to simulate the typical length of time between two orthodontic appointments. A final fluoride ion release measurement was taken of all the discs in the gel group 6 weeks after the fluoride gel treatment. The results of repeated-measures analysis indicated that there were no significant differences between the groups at baseline and after 7d of toothbrushing time points. Opal Seal exhibited a significant increase in fluoride uptake (1.0ppm) after 24hrs of fluoride gel exposure but these levels gradually decreasedover 6 weeks (0.04ppm). Pro Seal and Transbond showed no significant fluoride release after the gel or toothpaste applications. The fluoride-containing primer, Opal Seal, had the ability to be recharged with fluoride ions from APF gel. However, the amount of fluoride released from recharged discs decreased gradually over a 6 weeks of time.


© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

April 2012

Included in

Dentistry Commons