This in vitro study was designed to compare the effect of four manufacturing techniques, storage, chemical sterilization and autoclaving on accuracy of computer guided surgical guides. An impression for class III Kennedy classification partially edentulous case was made and poured into epoxy resin to construct a cast. The cast was laser scanned and a surgical guide was designed by the Blue sky software for implant planning. Four techniques were used for manufacturing which were SLS, milling, SLA and FDM.Measuring accuracy were done in three terms; evaluation of sleeve hole tolerance, guide adaptation and accuracy of sleeve angle. The sleeve hole tolerance was evaluated by special customized metal cylinders of different diameters where each diameter was used to evaluate its fit inside the sleeve hole. For the microgap photos were captured by digital microscope and then analyzed by image J software. Regarding angular deviation, laser scanning of the surgical guide with special customized metal cylinders both were sealed on the model was done then evaluating of angular deviation was carried by blue sky..The accuracy was measured in five phases after 24 hour of manufacturing, one week storage, two week storage, chemical sterilization and autoclaving. All results were tabulated and analyzed to reach conclusion.ConclusionsBased on the results of the current study the following can be concluded:1.Selective laser sintering was found to be more accurate than the other studied manufacturing techniques for surgical guides construction2.Dry storage has limited effect on theaccuracy of stereolithographic, milled and fused deposition modeled surgical guides, while it hadno effect on selective laser sintered ones.3.Chemical sterilization had no effect on the accuracy of the studied types of surgical guides.4. Stereolithographic guides were the only guides that resisted autoclaving.