Reproducibility of TMR for the Determination of Longitudinal Mineral Changes in Dental Hard Tissues

Abstract

Transverse microradiography (TMR) of thin sections is the principal method for determining mineral changes in experimental lesions. Because it has become also the standard by which newly-developed methods are validated, demands on all steps of the procedure are high. Thin sections of enamel and dentin require high-precision cutting or lapping to preserve surface structures, but their different brittleness and elasticity preclude a uniform procedure. Image analysis permits the measurement of fine details at a μm scale, but because most studies are aimed at overall mineral changes, they are usually lost on broadening of the scan areas and averaging of experimental groups. Small errors in repositioning of the scan areas for repetitive measurements may yield distorted lesion profiles, while quantitative data such as the integrated mineral loss are hardly influenced. A major reason for "irreproducibility" of TMR are the different definitions of the lesion parameters as used by various research groups. We recommend that these definitions be agreed on if the full potential of TMR as an international standard is to be utilized.

Keywords

Transverse microradiography enamel dentin caries lesion parameters.

Get full access to this article

View all access options for this article.

References

Angmar B. , Carlstrom D. , Glas JE ( 1963). Studies on the ultrastructure of dental enamel. IV. The mineralization of normal human enamel. J Ultrastruct Res 8:12-23.

Arends J. , ten Bosch JJ (1992). Demineralization and remineralization evaluation techniques. J Dent Res 71:924-928.

Damen Jjm , Exterkate Ram , ten Cate JM (1995). Lipoteichoic acid inhibits remineralization of artificial subsurface lesions and surface-softened enamel. J Dent Res 74:1689-1695.

De Josselin de Jong E. , ten Bosch JJ (1985). Error analysis of the microradiographic determination of mineral content in mineralized tissue slices. Phys Med Biol 30:1067-1075.

Exterkate Ram , Damen Jjm , ten Cate JM (1993). A single section model for enamel de- and remineralization studies. I. The effects of different Ca/P ratios in remineralization solutions . J Dent Res 72:1599-1603.

Lagerweij MD , De Josselin de Jong E. , ten Cate JM (1994). The video camera compared with the densitometer as a scanning device for microradiography. Caries Res 28 :353-362.

Lammers PC , Borggreven Jmpm , Driessens Fcm (1990). Influence of fluoride on in vitro remineralization of artificial subsurface lesions determined with a sandwich technique. Caries Res 24:81-85.

Mellberg JR , Castrovince LA , Rotsides ID (1986). In vivo remineralization by a monofluorophosphate dentifrice as determined with a thin-section sandwich technique. J Dent Res 65:1078-1083.

Ruben J. , Arends J. (1993). Shrinkage prevention of in vitro demineralized human dentine in transversal microradiography. Caries Res 27:262-265.

10.

ten Cate JM , Nyvad B. , Van de Plassche-Simons YM (1991). A quantitative analysis of mineral loss and shrinkage of in vitro demineralized human root surfaces. J Dent Res 70:1371-1374.

11.

ten Cate JM , Dundon KA , Vernon PG , Damato FA , Huntington E. , Exterkate Ram , et al. (1996). Preparation and measurement of artificial enamel lesions, a four-laboratory ring test. Caries Res 30:400-407.

12.

Van Strijp Ajp , Buijs MJ , ten Cate JM (1995). Contact microradiography of dentine under wet conditions to prevent lesion shrinkage. Caries Res 29:107-110.

13.

Wefel JS , Maharry GJ , Jensen ME , Harless JD (1987). Development of an intra-oral single section remineralization model. J Dent Res 66:1485-1489.

14.

White DJ , Faller RV , Bowman WD (1992). Demineralization and remineralization evaluation techniques-added considerations. J Dent Res 71:929-933.