Plaster of Paris splints were fabricated to a single specification: On a 60 mm diameter solid tube, a single pass of 10 cm “Webril” wool was wound onto the tube with 50% overlap. Then four passes of 10 cm “Gypsona” POP was wound onto the tube in successive opposing directions with 50% overlap, to give 8 layers. An additional turn was allowed at each end to reinforce the area of plaster to be supported in the jigs. Once hard, they were dried for 5 days to ensure they were all equivalent as on some occasions they were fabricated over several days, therefore some would otherwise be ‘wetter’ than others.
The test splints (including wool) were split longitudinally with a plaster saw whilst the control splints were left whole. All splints were weighed after drying. Each splint type underwent a trial protocol, including loading to destruction.
Twenty-one control splints were fabricated. Nine were assigned to 4 point bending, 9 were assigned to 3-point kinking, and 3 were assigned to torsion. The test splints were made and allocated for testing in the same distribution. Deflection and load readings were taken for all protocols.