There are several classes of<unk> s: * Graspers, such as forceps * Clamps and occluders for blood vessels and other organs (e.g. hemostats) *<unk>  scissors * Bone cutters: unpowered or powered saws, drills and pliers-like devices * Needle drivers, also known as needle holders, used to hold suture needle while it is passed through tissue and to grasp suture while instrument knot tying. * Retractors, used to spread open skin, ribs and other tissue * Distractors, positioners and stereotactic devices * Mechanical cutters (scalpels, lancets, trocars, Harmonic scalpel, rongeurs etc.) * Dilators and specula, for access to narrow passages or incisions * Suction tips and tubes, for removal of bodily fluids * Sealing devices, such as<unk>  staplers * Irrigation and injection needles, tips and tubes, for introducing fluid * Powered devices, such as cranial drills and dermatomes * Scopes and probes, including fiber optic endoscopes and tactile probes * Carriers and appliers for optical, electronic, and mechanical devices * Ultrasound tissue disruptors, cryotomes and cutting laser guides * Measurement devices, such as rulers and calipers An important relative distinction regarding<unk> s is the amount of bodily disruption or tissue trauma that their use might cause the patient. Terms relating to this issue are 'atraumatic' and minimally invasive.
Surgical instrument
Biological specimen
Bloodmobile
Vaccine ingredients
Durable medical equipment
Custom-made medical device
Perioperative medicine
Dental instrument