Morphology of the osteonal cement line in human bone

Abstract

While current consensus suggests the absence of collagen in osteonal cement lines, the extent of cement line mineralization and the nature of the ground substance within the cement line are unclear. Samples of human radius were examined by using scanning electron microscopy, electron microprobe, and histochemical techniques. X-ray intensities were used to compare the amount of calcium, phosphorus, and sulfur in cement lines with amounts in surrounding lamellar bone. The results indicate that cement lines contain significantly less calcium and phosphorus, but significantly more sulfur, than surrounding bone matrix. The Ca/P ratio of cement lines was significantly greater than that of lamellar bone, suggesting that the mineral in cement lines may not be in the form of mature hydroxyapatite. No selective staining of the cement lines could be demonstrated by using periodic acid-Schiff, Sudan black B, or alcian blue critical electrolyte concentration techniques.

Ultrastructural characterization and immunolocalization of osteopontin in rat calvarial osteoblast primary cultures

“…Although the potential alterations of mineral induced by aqueous tissue processing must be taken into consideration (Landis et al, 19771, our preliminary X-ray microanalysis data indicate a different C a p ratio over the afibrillar material than over the mineralized collagenous matrix. This differential in C a P ratios may be related in part to variations in mineral at these sites, similar to what has been reported for cement lines and matrix proper in bone (discussed in Schaffler et al, 1987). However, interpretation of any differences will require anhydrous tissue processing using organic solvents (Landis et al, 1977) or cryopreparation approaches.…”

Osteopontin at mineralized tissue interfaces in bone, teeth, and osseointegrated implants: Ultrastructural distribution and implications for mineralized tissue formation, turnover, and repair

“…As a final point regarding matrix and mineral organization in, and properties of, cement lines in bone, these structures may minimize accumulation of fatigue damage (Martin and Burr, 1982) by participating in "strain relief" and preventing microcrack propagation across neighboring osteons (Burr et al, 1988). Despite initial (Frasca, 1981;Philipson, 1965) and more recent (Chen et al, 1994;Frank et al, 1993;Ingram et al, 1993;Kang et al, 1994;McKee et al, 1992McKee et al, , 1993Schaffler et al, 1987) advances in characterizing cement line composition, more complete elucidation of their role awaits a better understanding of the biochemical interactions between matrix molecules (including proteoglycans and lipids), mineral, and the alloplasts currently used in medicine and dentistry.…”

Bone formation on two‐dimensional poly(DL‐lactide‐co‐glycolide) (PLGA) films and three‐dimensional PLGA tissue engineering scaffolds in vitro

“…This enables them to absorb energy and provides the resistance of osteonal bone to fatigue damage and crack growth. 11,12 Thus, the cement line is an interfacial structure in bone tissue, which provides many biomechanical characteristics in addition to adhesive functions. 13,14 Cement lines have been observed on a variety of biomaterial surfaces both in vitro and in vivo since their original experimental demonstration in 1991; 15 however, they have not been observed on PLGA.…”