The primary function of a slow-speed motor with a contra-angle handpiece attachment is indeed to remove decay and adjust restorations. This type of handpiece, when connected to a slow-speed motor, offers the dental professional the ability to effectively and precisely access and treat areas that require decay removal or adjustments to existing dental restorations.
The contra-angle design allows for greater maneuverability in the oral cavity, making it easier to position the instrument at various angles. The slower speed is particularly advantageous for procedures requiring fine control, helping to minimize heat generation, which can be damaging to dental pulp and surrounding tissues. This controlled speed is ideal for tasks like shaping and refining restorations, as well as delicately removing carious tissue without the risk of excessive trauma to the tooth structure.
In contrast, while polishing teeth is a function associated with the slow-speed motor and specific attachments, it is not the primary use. Cutting and vaporizing soft tissue falls under the domain of high-speed instruments and lasers, which are not used in conjunction with a slow-speed motor setup. Flushing internal coolant lines is relevant to the maintenance of handpieces but does not pertain to the operational functions of the handpiece during patient care.