Smart toothbrush designs are provided. In one aspect, a toothbrush is provided which includes: a handle portion; and a head portion attached to the handle portion, wherein the head portion has bristles, a sample testing chamber containing at least one electronic sensor, a removable tip for drawing saliva samples into the sample testing chamber, and a calibration solution reservoir connected to the sample testing chamber. In another aspect, the head portion of the toothbrush has at least one optical sensor. A method for acquiring user data using the present smart toothbrush designs is also provided.