You need to determine which degradable material to use as a tissue engineering scaffold for repair of a critical-sized bone defect. (A critical-size defect is one that will not heal unaided.) You are planning to seed the scaffold with cells then implant it into the defect. While the cells proliferate and generate bone, the scaffold will degrade and create void space into which the new tissue may grow. What

The question bus incomplete, below is the complete question;

You need to determine which degradable material to use as a tissue engineering scaffold for repair of a critical-sized bone defect. (A critical-size defect is one that will not heal unaided.) You are planning to seed the scaffold with cells then implant it into the defect. While the cells proliferate and generate bone, the scaffold will degrade and create void space into which the new tissue may grow. What degradation method would you prefer for this scaffold material and why ?

(Hydrolytic vs Enzymatic degradation, Bulk vs Surface degradation).

The correct answer to the question is Degradation via Hydrolysis.

This Degradation via Hydrolysis will be most preferred and suitable in this application because,as a result of the aqueous environment between the patients, the lack of need for placing a target on the degradation areas (Since it is implanted into the site that has defect, it is accessible by water because it is already localized).

The bulk degradation of the scaffold will also be considered because since the overall dimensions will be consistent, over a given period of time.

But if the material underwent surface degradation, the implant could loosen up before there is sufficient tissue repair has developed or even fall out of the defect..

Or any cells that are seeded can equally detached itself from the scaffold.

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