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Nightguard vital bleaching of tetracycline-stained teeth: 90 months post treatment
Ralph H Leonard1, B Van Haywood, Daniel J Caplan
1Department of Diagnostic Sciences and General Dentistry, University of North Carolina School of Dentistry, Chapel Hill, NC 27599-7450, USA. Ralph_Leonard@dentistry.unc.edu
Purpose:
The purpose of this longitudinal whitening study was to determine the stability, post-treatment side effects, and patient satisfaction at 90 months post treatment after 6 months of active treatment of tetracycline-stained teeth with 10% carbamide peroxide.
Materials And Methods:
Fifteen of 21 participants enrolled in the study (71%) were contacted and asked to participate in a survey concerning their whitening experience. Participants were asked whether there had been any change in the shade of their teeth after treatment and if they had experienced any side effects that they believed were treatment related. Eight of the 15 participated in a clinical examination.
Results:
Nine participants (60%) reported no obvious shade change or only a slight darkening not noticed by others. None reported darkening back to the original shade; however, four had re-treated their teeth. Examiners were in agreement with the participants' perception of shade change upon comparing pretreatment and post-treatment photographs and Vita shade (Vita Zahnfabrik D-79713, Bad Sackingen, Germany) values. The degree of improvement over the pretreatment shade was significant for the 90-month post-treatment shade (p < .01). All respondents (n = 15) denied having to have a crown or root canal or tooth sensitivity that they believed was treatment related.
Clinical Significance:
The results of this study of nightguard vital bleaching indicate that tetracycline-stained teeth can be whitened successfully using extended treatment time and that shade stability may last at least 90 months post treatment (range 84-100 mo). Patients participating in this study were over-whelmingly positive about the procedure in terms of shade retention and lack of post-treatment side effects.
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