This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Fonseca, A A Articles by Carapeto, L P PubMed PubMed Citation Articles by Fonseca, A A Articles by Carapeto, L P

Effect of 10% formalin on radiographic optical density of bone specimens

¹ Stomatology Department, Pontifical Catholic University of Rio Grande do Sul, Hospital São Lucas, Porto Alegre, Brazil, ² Radiology Department, Faculty of Odontology, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil, ³ Department of Environmental Science, Porto Alegre, Rio Grande do Sul, Brazil, ⁴ Division of Image Diagnosis of Veterinary Hospital, Federal University of Pelotas, Rio Grande do Sul, Brazil

*Correspondence to: Dr Karen Cherubini, Assistant Professor of Stomatology, Stomatology Department, Pontifical Catholic University of Rio Grande do Sul, Av. Ipiranga, 6690 Sala 231, Hospital São Lucas PUCRS, Porto Alegre, RS 90610000, Brazil; E-mail: kebini.ez{at}terra.com.br

Received 27 March 2007; revised 11 May 2007; accepted 15 May 2007

Objectives: The aim of this work was to determine whether the fixation process with 10% formalin modifies the radiographic optical density of bone.

Methods: Eight rabbit tibiae were placed in separate containers with one of the following fixative solutions: 10% formalin (n = 3), 10% phosphate-buffered formalin (n = 3) or 10% calcium carbonate-buffered formalin (n = 2). Radiographs were obtained at 5 different times: before fixation (time zero), then 1 day, 15 days, 30 days and 90 days following immersion in the fixative solution. Radiographs were scanned and optical density was determined using ImageTool software.

Results: There was no significant difference in radiographic optical density among the specimens fixed in 10% formalin (146.60±32.44), 10% phosphate-buffered formalin (149.84±32.43) and 10% calcium carbonate-buffered formalin (146.61±35.92). Regardless of buffering, optical density at time zero was significantly higher than that at 15 days, 30 days and 90 days. However, while optical density at 1 day was significantly higher than that at 30 days and 90 days, it did not differ from that at 15 days. There was also no significant difference in density between 30 days and 90 days (ANOVA, Tukey, at 5% level of significance).

Conclusion: The radiographic optical density of specimens stored in 10% formalin diminishes with time, irrespective of buffering, which suggests the occurrence of bone demineralization.

Keywords: demineralization; bone tissue; formaldehyde; radiograph