Sorry to say, it can. In fact, anything involving contact with saliva—a kiss, parents tasting their babies’ food, sharing of tableware and toothbrushes—can transmit decay-causing bacteria.
Soon after birth, infants start to get those bacteria that inhabit the mouth and cause cavities. These germs are usually transferred by the babies’ mothers or other family members.
When one so innocent can be SO susceptible, we need to provide our mouths with the best defense against the enemy. Brushing and flossing are a good beginning, as they interrupt the growth of bacterial plaque. Getting teeth straightened can help because straight teeth are better able to resist cavities. Less frequent snacking and diets low in sugary foods reduce the amount of bacteria acids on teeth. Sealants applied to the biting grooves can prevent germs from adhering to teeth.
Regular checkups are crucial. If we detect decay in its earliest stages—and you keep your mouth plaque-free—tooth enamel can actually remineralize and harden up again. Otherwise, you may want to give up kissing.