General Chairside Assisting (GC)
What the exam measures
Chairside questions test whether you can anticipate the dentist's next instrument, material, or patient need. Organize your study around four clusters.
Armamentarium and four-handed dentistry. Know instrument categories (exam/exploring, hand-cutting, restorative, accessory) and grasp principles: a stable fulcrum on a firm tooth surface, a pen grasp for precision, and transfer zones that keep the working end visible and never pass over the patient's face. Suction selection matters: high-volume evacuation retracts tissue and clears fluid, while the saliva ejector only removes pooled fluid and depends on the patient being able to close the lips.
Isolation and moisture control. Rubber dam, cotton rolls, retraction cord, and matrices with wedges are all fair game. A wedge adapts the matrix band interproximally and retracts tissue; it does not replace the matrix.
Materials. Learn working time versus setting time, and how temperature, humidity, and powder-to-water ratio shift both. Alginate is an irreversible hydrocolloid: measure powder and water exactly per the manufacturer, spatulate with a sweeping motion to avoid bubbles, and remember cool water lengthens working time while warm water shortens it. For gypsum, more water means a weaker, slower-setting, more expanded cast. Composite bonds to etched enamel, and zinc oxide-eugenol bases inhibit composite polymerization, so they are avoided beneath it.
Charting and patient care. Universal numbering 1 through 32 begins with the maxillary right third molar; primary teeth use A through T. Record existing restorations, missing teeth, and periodontal findings accurately, and never chart a procedure before it is completed.
Trap to expect
Questions that swap working time with setting time, or that assume a wedge substitutes for a matrix band.
Rule of thumb
If a material must be mixed, the manufacturer's scoop-and-cup ratio is non-negotiable; altering it is the most common cause of a failed impression or cast.