In vivo study of pixel grey-measurement in digital subtraction radiography for monitoring caries remineralization.
OBJECTIVE
The aim of this study was to evaluate the performance of a quantitative method, based on pixel grey value measurements, for monitoring caries remineralization.


METHODS
Proximal radiographs of 11 patients (61 enamel caries lesions) were taken both before and after a 2 month remineralization protocol. Radiographs were digitized and for each area a follow-up image was subtracted from a baseline image. A quantitative analysis was undertaken using ImageTool software (University of Texas Health Science Center, San Antonio, TX). For each caries lesion diagnosed, a mean pixel value was obtained in digital subtraction radiographs (SR) using a scale ranging from 0-255 grey values. To identify caries status after the remineralization protocol, a subjective analysis of SR was undertaken by 6 radiologists who graded the lesions as demineralized (n = 10), unchanged (n = 34) or remineralized (n = 17).


RESULTS
There was a statistically significant difference between the mean pixel values for demineralized (112.1+/-14.4), unchanged (127.3+/-12.3) and remineralized (137.5+/-13.8) lesions.


CONCLUSIONS
It was concluded that the status of proximal caries lesions after remineralization therapy can be assessed by pixel grey measurements in SR and may constitute a suitable complementary method for monitoring the results of remineralization protocol in clinical practice.
Carneiro
L S
LS
School of Dentistry, Federal University of Goiás, Goiânia, Brazil.
Nunes
C A
CA
Silva
M A
MA
Leles
C R
CR
Mendonça
E F
EF
D000134:Acid Etching, Dental; D000149:Acidulated Phosphate Fluoride / Q000627:therapeutic use; D000293:Adolescent; D000328:Adult; D017607:Aluminum Compounds / Q000627:therapeutic use; D002327:Cariostatic Agents / Q000627:therapeutic use; D003731:Dental Caries / Q000000981:diagnostic imaging* / Q000628:therapy; D003743:Dental Enamel / Q000000981:diagnostic imaging; D003777:Dental Prophylaxis; D003804:Dentin / Q000000981:diagnostic imaging; D005260:Female; D005460:Fluorides, Topical / Q000627:therapeutic use; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D009566:Nitrates / Q000627:therapeutic use; D011856:Radiographic Image Enhancement / Q000379:methods*; D016300:Radiography, Bitewing; D012984:Software; D013382:Subtraction Technique; D014089:Tooth Remineralization; D016896:Treatment Outcome; D055815:Young Adult
D017607:Aluminum Compounds; D002327:Cariostatic Agents; D005460:Fluorides, Topical; D009566:Nitrates; D000149:Acidulated Phosphate Fluoride; C050609:aluminum nitrate