Water sorption and dimensional changes of denture base polymer reinforced with glass fibers in continuous unidirectional and woven form

Purpose: The aim of this study was to determine the dimensional accuracy an d water sorption of a denture base polymer that was reinforced with glass f ibers in continuous unidirectional and woven form in different weight fract ions. Materials and Methods: Ten rhombic brass plates were prepared with re ference points, and 70 heat-cured denture base polymer specimens were produ ced using these brass models. Ten of 70 were used for controls, and 60 were reinforced with grass fibers in continuous parallel and woven form. The di mensional changes of polymer and fiber-reinforced composite specimens after processing, drying for 4 days at 37 degreesC, and storage in 37 degreesC w ater for 90 days were calculated by the change of the distance vector. The measurements were made between the reference points on the specimens and we re compared with those on the brass model at 4 different stages. The water sorption calculations were made at 10 different time intervals on 70 specim ens, which were immersed in a 37 degreesC distilled water bath and weighed. Results: The polymerization shrinkage and water sorption of denture base p olymers is lower when the specimens are reinforced with glass fibers in con tinuous unidirectional and woven form. The highest fiber content showed the smallest dimensional change (0.069 mm, or 0.25%), and the unreinforced gro up showed the largest change (0.139 mm, or 0.54%). Water sorption occurred mainly during the first 14 days. Conclusion: As the fiber content increases , the dimensional change and water sorption decrease.