1. 专科医师：因此,涉及美容齿学的医师必须具备较为广泛的口腔基础知识和丰富的临床经验,他的治疗实际上已是超过了一个普通医师的治疗范畴,属专科医师(Specialist)治疗范畴,而涉及美容齿学的医师基本上都属专科医师,如正畸医师(Orthodontist),

2. 专科医生：加拿大的医生基本上分为家庭医生(Family Doctors)与专科医生(Specialist). 一般来说,每个家庭都要指定一名家庭医生,大部分的病症都由家庭医生诊治. 病人可与家庭医生讨论计划生育、饮食营养和心理方面的问题,所以家庭医生也是全科医生.

1. 专家
    A specialist is a person who has a particular skill or knows a lot about a particular subject.

    e.g. If you are housebound, you can arrange for a home visit from a specialist adviser...
           如果你出不了门，可以预约专家顾问上门就诊。
    e.g. Peckham, himself a cancer specialist, is well aware of the wide variations in medical practice.
           佩卡姆本人是一名癌症专家，他非常了解不同治疗方法之间的巨大差异。

1. an expert who is devoted to one occupation or branch of learning

    Synonym: specializerspecialiser

2. practices one branch of medicine

    Synonym: medical specialist