Practical How To: GUIDOR® easy-graft™ CLASSIC Alloplastic Bone Grafting System

This post was prepared in collaboration with Sunstar.

On an experimental basis, we have asked a limited number of companies to provide us with practical “How To” answers to clinical questions. We were prompted to conduct this experiment when dental team members told us that they visit company websites and consult company representatives for practical clinical information. We look forward to receiving your feedback on this experiment.

Most dimensional changes of the socket ridge occur in the first 3 - 6 months after a tooth extraction. After 6 months, the patient could have horizontal bone loss of 29-63% and vertical bone loss of 11-22%. ¹ This loss of bone structure makes any future restoration procedure more complex.

Minimally invasive ridge-preservation procedures, using a bone grafting substitute, are effective techniques for preserving ridge dimensions. “Bone graft substitutes are mainly offered in the form of granules that are placed in a bowl, mixed with blood or saline, transferred in several steps to the defect site, and are completely covered by a membrane to keep the granules stable in the site.

This suboptimal handling procedure was the motivation to engineer a better, more user-friendly, less cumbersome product. The objective was to develop a product that would be placed directly into the site using a syringe, that would adjust to the contours of the defect, and then harden to a stable scaffold while being completely resorbable.

This goal was achieved by creating a novel patented composite biomaterial called GUIDOR easy-graft CLASSIC that is supplied in a syringe and which possesses unique easy handling properties.² 

Material Composition

GUIDOR® easy-graft™ CLASSIC Alloplastic Bone Grafting System is a complete system available from Sunstar that helps clinicians provide more predictable clinical results. Each system is comprised of β-tricalcium phosphate (β-TCP) granules coated with a biodegradable polymer called poly(lactide-co-glycolide) (PLGA) that is mixed with N-methyl-2-pyrrolidone (NMP) liquid activator called BioLinker™ to form a permeable, moldable material which hardens to form a stable, porous scaffold. 

Step 1: The system contains BioLinker™ and β-TCP granules with polymer coating. Step 2: When mixed, BioLinker™ softens the polymer coating creating a sticky surface that can be compressed and shaped. Step 3: GUIDOR® easy-graft™ CLASSIC hardens in approximately one minute into a stable, porous scaffold of interconnected granules.

Granule Porosity

The porous nature of the material used in GUIDOR® easy-graft™ CLASSIC Alloplastic Bone Grafting System is a key factor for bone regeneration.

	β-TCP granule (A) with a polylactide polymer coating (B)3: To ensure the retention of a comprehensive, intact pore system, each pressure-resistant granule is designed to resist fragmentation or crumbling during application.
	Macroporosity of GUIDOR® easy-graft™ CLASSIC material3: Subsequent to mixing and dispensing GUIDOR® easy-graft™ CLASSIC material, macropores will exist in the spaces between the round, pressure-resistant granules. These larger pores provide space for the formation of new bone and the development of blood vessels.
	Microporosity of GUIDOR® easy-graft™ CLASSIC material1: GUIDOR® easy-graft™ CLASSIC material is openly microporous with a total porosity of approximately 70%. When viewing the SEM image, the microporous nature of this bone graft appears as dark areas within each granule. Studies have shown fully microporous calcium phosphates (pore size 1 μm to 10 μm) provide increased osteoconductivity and bone formation in comparison to materials without micropores.4,5

Resorption

GUIDOR® easy-graft™ CLASSIC Alloplastic Bone Grafting System is designed to offer complete resorption via physiological dissolution and cell-based mechanisms in 5-15 months, depending upon biological and medical factors. The resorption of the GUIDOR® easy-graft™ CLASSIC (A) occurs as new bone (B) is formed. As the material resorbs, the granule of GUIDOR® easy-graft™ CLASSIC (A) is no longer spherical in shape. At the same time, new bone (B) forms and fills the accessible space.⁶

Courtesy of Dr. Leventis (Athens, Greece) and Dr. Heiner Nagursky (University of Freiburg, Germany)

An independent healthcare market research firm conducted a blind product evaluation, where 80 US dentists tried GUIDOR® easy-graft™ CLASSIC for the first time. From 2014-2015, the respondents indicated they completed a total of 300+ cases with an average of 5 case per clinician and provided feedback aafter 3 months (N=75) and 6 months (N=65).* *Data on File, DOF-0007

References

1. Tan WL, Wong TLT, Wong MCM, Lang NP. A systematic review of post-extractional alveolar hard and soft tissue dimensional changes in humans. Clin. Oral. Impl. Res. 23(Suppl. 5), 2012, 1–21.
2. Ruffieux, Kurt. A New Syringe-Delivered, Moldable, Alloplastic Bone Graft Substitute. Compendium for Continuing Education in Dentistry. 2014; 35(4): 8-10.
3. Scanning electron microscope (SEM) image
4. Habibovic P., Sees T. M., van den Doel M. A., van Blitterswijk C. A. and de Groot K.: Osteoinduction by biomaterials – physicochemical and structural influences J Biomed Mater Res A ( 2006 ) 77( 4 ): 747-62.
5. Hing K. A., Annaz B., Saeed S., Revell P. A. and Buckland T.: Microporosity enhances bioactivity of synthetic bone graft substitutes J Mater Sci Mater Med (2005) 16(5): 467-75
6. Human histology at 4 months after placement of GUIDOR® easy-graft™ CLASSIC. Courtesy of Dr. Minas Leventis (Athens, Greece) and Dr. Heiner Nagursky (University of Freiburg, Germany).