Is it true that the parotid duct is positively associated with dental cavities right around the 2nd molar where it empties? if so, why?

No.: High salivary flow adjacent to ducts is more often associated with tartar or calculus formation than with tooth decay. Actually may be protective for tooth decay.

Probably not: Having saliva rinsing the teeth is very healthy. However, we do find calculus (tartar) around the salivary ducts in people who dont clean their mouths adequately.

Parotid duct ; decay: As a result of the duct emptying into the mouth near the maxillary 2nd molar, many patients get calculus here. Decay is usually the result of a poor diet choices and inadequate brushing habits/techniques. Get the cavity fixed and keep the area clean and you should be fine.Failing to brush the area well.