Entry in to most dental assistant programs requires the minimum academic level of a high school diploma or equivalent. Specific programs may require the applicant to have studied science (chemistry and biology) and/or computers whilst at high school to be eligible for admission. Alternatively, the applicant needs to have had relevant work experience as a dental assistant either full time for two years or part time for four years. Current certification in cardio-pulmonary resuscitation is also required. After obtaining initial certification, the individual has to be re-certified annually by earning continuing educational credits. Apart from the DANB certification, there are various organizations, predominantly at state level, that offer registration as a dental assistant through their individual dental assistant programs.