Quantitative analysis of KTP laser photodynamic bleaching of tetracycline-discolored teeth.
OBJECTIVE
Photodynamic bleaching is a recently developed method that may be suitable for photo-oxidation of difficult internal stains. This study examined the outcomes of photodynamic bleaching for treatment of confirmed cases of tetracycline discoloration, when used as a single-appointment procedure.


METHODS
Digital analysis of standardized pre- and post-treatment digital photographs of a total of 90 maxillary incisors from 23 adult patients undergoing photodynamic bleaching was undertaken. The patients were treated by a visible green KTP laser (wavelength 532 nm) combined with a rhodamine-B photosensitizer gel (Smartbleach) applied to the teeth and activated for 30 sec. Each tooth underwent four cycles of 30 sec of laser exposure. Digital image analysis was undertaken in a blinded manner, and we examined changes in the four maxillary incisors in terms of blue pixel intensity (yellowness).


RESULTS
Least squares linear regression analysis and a one-tailed paired t-test using the matched pairs of pre- and post-treatment data for mean blue pixel intensity showed that a significant lightening effect was achieved by the bleaching treatment. Significant increases in blue pixel intensity (reductions in yellowness) occurred in 78% of the teeth treated.


CONCLUSIONS
In-office KTP laser photodynamic bleaching provides a clinically useful improvement in tooth shade in teeth with tetracycline discoloration.
Kuzekanani
Maryam
M
Kerman Dental School, Kerman University of Medical Sciences and Health Services, Kerman, Iran.
Walsh
Laurence J
LJ
D000328:Adult; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D005260:Female; D005456:Fluorescent Dyes / Q000008:administration & dosage*; D005782:Gels; D006801:Humans; D007180:Incisor; D053685:Laser Therapy / Q000295:instrumentation*; D016018:Least-Squares Analysis; D008297:Male; D008437:Maxilla; D008875:Middle Aged; D010781:Photography; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D012235:Rhodamines / Q000008:administration & dosage*; D013752:Tetracycline / Q000009:adverse effects*; D014073:Tooth Bleaching / Q000379:methods*; D014075:Tooth Discoloration / Q000139:chemically induced* / Q000628:therapy*; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D005456:Fluorescent Dyes; D005782:Gels; D017319:Photosensitizing Agents; D012235:Rhodamines; D013752:Tetracycline; C029773:rhodamine B