DR. COOK GUARANTEES FREE CROWN, BRIDGE AND ONLAY REPLACEMENT FOR FIVE YEARS! Dr. Cook's 5-year guarantee on workmanship remains in effect provided patients return for maintenance and cleaning, as determined by individual patient need, and as recommended and recalled by Dr. Cook. Dr. Cook and his exceptional staff provide clear treatment plan options and preventative maintenance schedules specifically tailored to you, and will discuss all recommendations for maintenance with regards to individual patients' crowns, bridges and onlays.