Yongyudh Vajaradul
Siriraj Hospital, Mahidol University, Bangkok, Thailand

Hendadura Piyanandana Jayathilaka
Medical Lab Technologist
Sri Lanka Model Human Tissue Bank

Introduction:

Bone substitutes prepared from bovine bone decalcified by muriatic acid treatment has already been used to fill small bone defect more then 100 years ago. Bone substitute materials can be grouped into the main group, they are 1). Calcium phosphate like Osporum (deproteinize bone), Kiel Bone (organic bone), Oswestry bone marketed today as macroporous Bio-OssR and EndoboneR.

One of the major disadvantage of freeze dried bone allografts is that they are brittle in nature and do not have sufficient compression strength to sustain the body load on the host-allograft juncture. There has been many attempts world wide for various kind of bone substittues and to some extent sucess has also been achieved. The Bangkok Biomaterial Center, along with its instrinc strength of a full fledge laboratory and the dynamic leadership of Prof. Yongyudh Vajaradul has commenced on the production of Radiation Sterilized Freeze Dried Bone Allograft Tablets. The major area of applications of these bone substitute products are stone brick support in spinal deformities, dental cavities, oral & maxillofacial surgeries and filling up of holes caused due to bone loss. This project was in the pipe-line for more than 2 years due to huge overload of on-going research works. However in August 2000, the bone tablet project study was launched. A unique feature of this manufacturing cum-research project is that the inital phase i.e Bovine Bone Model work has been entirely done by the International Atomic Energy Agency Fellows of the 2nd batch Master Degree Course.

OBJECTIVES

	Include production of bone tablets in the product line of Bangkok Biomaterial Center.
	To conduct comparative study of biomechanical properties of human and bovine bone tablets.
	To determine the clinical effectiveness of bone tablets.
	To study the feasibility of commencing production of bone tablets in industrial scale.
	To establish the process and prepare a blue print of resources for manufacturing, chemical and bio-mechanical laboratory testings and clinical trials.
	To keep with the trend of research & development and innovative products from Bangkok Biomaterial Center.
	To promote the cause of research & developments in the field of Tissue Banking.
	To orient and impart practical training to the Advance Training Course -Cum- Master Degree students (IAEA Fellows) through the system of conducting on-hand research & developments in advance topics of radiation sterilization and tissue banking.

PROCEDURE

Manufactuing stages and other technical details of this product are covered under the product patent and thereby all the details cannot be disclosed at this stage. However it is expected once the patent process is completed, the complete details shall be presented as a scientific paper in tissue banking journals and text books. However in the interest of our valuable readers, we are tempted to shed a little light on the manufacturing procedure but only on the Bovine Bone Tablet manufacturing.

Material and Methods

Bovine Bone. Bovine bone is purchased from the market, put into ice container, and transported to Bangkok Biomaterial Center.

Chemical.

	Hydrogen peroxide 3%. 100 ml of 6% Hydrogen Peroxide diluted with bio-filtered water until 200ml.
	Sodium Hypo-Chlorite 0.5%. 17.5 ml of 5.7% Sodium hypo-Chlorite diluted with bio- filtered water until 200 ml
	Bio-filtered water
	70% of ethanol

Equipment and Instrument

	Scalpel and blade
	Forceps
	Bone cutter
	Scissors
	Band saw machine
	Varnier caliper
	Washing machine
	Ultrasonic cleaner
	Bone grinding machine
	Freeze Drier machine
	Vacuum sealing machine
	Sterile PE bag
	Sterile Tray
	Beaker glass
	Measuring Cylinder
	Compressor machine for mold the bone (KORSCHR)

WORKING STEPS

	All the soft tissue and fat from bovine bone (ribs) are removed by using scalpel.
	The cleaned bone is cut into 1 cm of length by using the band saw machine and re-cut 2 times longitudinally to 3 pieces.
	The cut bone is washed with bio-filtered water in washing machine for 15 minutes and the washing is repeated again 3 times.
	The cut bone is soaked in 200 ml of 3% Hydrogen Peroxide for 30 minutes and then washed with bio-filtered water in washing machine for 15 minutes.
	Cleaned bone is soaked with bio-filtered water and cleaned in an ultrasonic water bath at room temperature for 15 minutes.
	The bone is then soaked in 0.5% of Sodium hypo-Chlorite for 15 minutes and then washed with biofiltered water in ultrasonic cleaner for 15 minutes and this process is repeated again 3 times.
	Bone is grinded with a bone grinder and the ground bone is divided into two group,the they are freeze-dried and non freeze dried.
	The bone is then sent to the pharmaceutical factory for moulding into tablet form.
	Mechanical and chemical properties of the bone tablets are determined at KMIT and MTEC.

CONCLUSIONS

It is expected that this innovative product of bone tablet from Bangkok Biomaterial Center will revolutionize the clinical applicationof allografts and will be a step into the new millenium of tissue banking.

Bovine bone being cleaned of soft tissue                             Cleaned bone being measured before cutting

Cut bone chip put in the washing machine                  Cleaned bone being treated with Hydrogen peroxide

Cleaning in ultrasonic bath with Hydrogen peroxide               Overnight treatment in Hydrogen peroxide

Cleaning in ultrasonic bath                                   Sodium Hypochlorite treatment

Washed and clean bone chips                             Bone chips being put in the grinding machine

2nd Batch bone chips lyophilized and vacuum packed              Round bone tablet sample

Round bone tablet sample without any mixture       Oval bone tablet with & without skimmed milk powder

Bone tablet of various type packed in blister packing      Compression test of round bone tablet in progress 

BACK TO HOMEPAGE