Acid-etching technique of non-decalcified bone samples for visualizing osteocyte-lacuno-canalicular network using scanning electron microscope

ABSTRACT

The aim of this study was to define the acid-etching technique for bone samples embedded in polymethyl metacrylate (PMMA) in order to visualize the osteocyte lacuno-canalicular network (LCN) for scanning electron microscopy (SEM). Human jaw bone tissue samples (N = 18) were collected from the study population consisting of patients having received dental implant surgery. After collection, the bone samples were fixed in 70% ethanol and non-decalcified samples embedded routinely into polymethyl metacrylate (PMMA). The PMMA embedded specimens were acid-etched in either 9 or 37% phosphoric acid (PA) and prepared for SEM for further analysis. PMMA embedded bone specimens acid-etched by 9% PA concentration accomplishes the most informative and favorable visualization of the LCN to be observed by SEM. Etching of PMMA embedded specimens is recommendable to start with 30 s or 40 s etching duration in order to find the proper etching duration for the samples examined. Visualizing osteocytes and LCN provides a tool to study bone structure that reflects changes in bone metabolism and diseases related to bone tissue. By proper etching protocol of non-decalcified and using scanning electron microscope it is possible to visualize the morphology of osteocytes and the network supporting vitality of bone tissue.

KEYWORDS:

• Osteocytes
• dendrites
• scanning electron microscopy
• mandible
• lacuno-canalicular network

Acknowledgments

The authors would like to thank Mrs Ritva Savolainen and Mrs Virpi Miettinen, SIB Labs, University of Eastern Finland, for their kind help in preparation of the bone specimens.

Declaration of interest

No potential conflict of interest was reported by the authors.