Kim Loos Dr. Kimberly A. Loos practices general dentistry in San Jose, California. She is also a clinical instructor at University of Pacific School of Dentistry and an editor for Dentistry On-Line. Numerous studies indicate that Streptococcus mutans, the main bacteria implicated in causing dental decay, or caries, is transmissible. While this bacteria can be transmitted between various family members, there appears to be a strong link between mother and child. The mode of transmission appears to be through either direct or indirect contact.
Direct contact occurs most commonly via kissing.
Streptococcus mutans can be transmitted by saliva. Indirect contact occurs through shared contaminated objects such as eating utensils, toothbrushes, cups, and even toys. Transmission occurs after teeth have begun erupting as Streptococcus mutans has difficulty colonizing other oral surfaces. The main time frame for susceptibility by the child appears to be between about 19 to 31 months with a median age of 26 months. Parents should be aware that transmission is not necessarily limited to this window of time.