Human cranial bone structure and the healing of cranial bone grafts: a study using backscattered electron imaging and confocal microscopy

Abstract

This study explored the microstructure of human cranial bone at different ages, and the survival, remodelling and modelling of cranial bone grafts. A combination of reflection and fluorescence confocal optical microscopy and scanning electron microscopy in the backscattered electron imaging mode was employed to examine highly polished block faces of plastic-embedded bone fragments as harvested for grafting, or recovered after a period in situ as a graft. The methods enabled remarkably detailed information on bone content, maturation and turnover to be gleaned from tiny scraps of bone. Microfractures in the harvested bone were repaired at the graft site, with welding of old and new bone indicating revascularization. Human cranial bone grafts successfully stimulated bone cell differentiation, supported new bone formation on resorbed and unresorbed surfaces, and underwent bone turnover. The type and organization of new bone reflected the growth rate and maturation of the graft rather than the age of the patient.

Characteristics of Newly Formed Bone during Guided Bone Regeneration: Observations by Immunohistochemistry and Confocal Laser Scanning Microscopy.

“…This method makes it possible to detect the mineralization of newly formed bones 2,3,11,12,29,30) . Recently, many studies of tissue mineralization using confocal laser scanning microscopy have been reported 4,10,18) . Kazama et al 18) suggested that sections used for light microscopic observations should be less than 10m in thickness, and processing the thin ground sections of non-demineralized tissues is technically difficult 4,18) .…”

“…Recently, many studies of tissue mineralization using confocal laser scanning microscopy have been reported 4,10,18) . Kazama et al 18) suggested that sections used for light microscopic observations should be less than 10m in thickness, and processing the thin ground sections of non-demineralized tissues is technically difficult 4,18) . However, confocal laser scanning microscopy makes it relatively easy to observe the positional relations using thin sections and observing the sectioning Fig.…”

“…Vital staining is a traditional technique using tetracycline and calcein to characterize bone mineralization 2,11,12,30) , recently, confocal laser scanning microscopy has also been used 3,4,10,18) . However, few studies have combinated vital staining with confocal laser scanning microscopy 4) .…”

“…However, few studies have combinated vital staining with confocal laser scanning microscopy 4) . Although there are many reports examining of cell proliferation, differentiation or tissue regeneration 7,14,15,19,23,28,32) , there are only a few using immunohistochemistry.…”

Confocal/two-photon microscopy in studying colonisation of cancer cells in bone using xenograft mouse models

“…Therefore, sharper images with better contrast and higher resolution could be achieved using a confocal microscope, compared with the commonly used wide-field fluorescence microscope ( Figure 1a). Since the first application in studying human cranial bone microstructure by Alan Boyde in 1990, 3 confocal microscopy has become a powerful tool in research related to the skeletal system, such as assessment of bone microdamage under physiological and pathological conditions. [4][5][6] Confocal microscopy has also provided opportunities to investigate bone cell-to-cell interactions in three-dimension, which is particular important for research involving osteocytes and osteoblasts.…”