The water and heat from modern dishwashers will damage your cutting board and must be avoided. You might get away with it a couple times, but your board will eventually break down and you will end up with wooden planks and not a cutting board if you continue to do it. Boards should be washed by hand with a mild soap, hot water and a non abrasive cloth or plastic scrubber. Do not allow the boards to sit in sink water. Wash it and take it out. Towel dry the board and allow to dry while standing up on an edge. This will cause the board to dry completely and prevent damage. If you dry the board laying flat on a surface the water that is trapped under the board might cause the board to warp slightly.