Dentist’s Order : is the prescription or order of the dentist whether verbal or written. It is an indication of the dentist's professional autonomy he/she can order and perform the treatment without the intervention of other professionals such as a physician. It is not a mechanical act but an independent duty. This order can be directed to himself/herself or his/ her dental assistant, dental hygienist, who performs it upon the former's instruction or direction. Dentist-as-a-Witness Rule The court may call a dentist to serve as witness to a case. A dentist may be considered as an ordinary witness or an expert witness. An ordinary witness is one who can testify as to the condition. There are two common type of expert witness : 1- Percipient or Fact Witness : Who gives opinion based on actual facts or knowledge. 2- Non- Percipient or non-Fact Witness: Who is not involved with the subject but is asked questions based on hypothetical situations.