If you haven't had your teeth cleaned in a long time or have had a lot of problems with your teeth, you may have to get a procedure called scaling and root planing, which involves cleaning the root surfaces of your teeth, which is more expensive than a routine visit.
The key background to this question is the nature of sound waves and light waves. Youâre right in that sound waves are a vibration traveling through an object, including condensed things like solids and liquids. In solids, those waves can consist of either alternating compressed and stretched regions, or regions wiggling sideways, compared to the direction the wave is traveling.
Top: Sound waves are longitudinal waves: the air moves back and forth along the same line as the wave travels, making alternate patterns of compressions and rarefactions. Bottom: Ocean waves are transverse waves: the water moves back and forth at right angles to the line in which the wave travels.