Home » Dentist in Homewood » Dentist in Homewood Explains: Are cavities contagious?

For decades, the scientific community held a steadfast belief that cavities were communicable diseases. Indeed, it was widely believed that kissing and sharing food could spread cavities, much in the way that influenza or colds spread. However, new evidence suggests otherwise. Our dentist in Homewood, IL, is here to explain.

Do you have questions about your smile? Ask the team at Signature Smile Arts in Homewood, IL! We give patients accurate and up-to-date information on the latest dental discoveries, making us leaders in modern dentistry. Learn more about your chompers by calling Dr. Alex Shore at (708) 799-5353 now! 

Present-day science now suggests that cavities are more intricately linked to an individual’s oral microbiome and lifestyle choices, rather than being a direct result of swapping bacteria through saliva transfer. Our dentist in Homewood, IL, is here to clarify.

The Historical View: Cavities as Communicable Diseases

Historically, dental professionals perceived cavities as infections that could be transmitted between individuals. This belief was rooted in the understanding that the bacteria responsible for tooth decay, primarily Streptococcus mutans, could be transferred via saliva

Consequently, actions like sharing utensils, kissing, or even close contact were thought to facilitate the spread of these “cavity-causing” bacteria. This model painted a somewhat simplistic picture, equating the transmission of oral bacteria with the spread of cavities themselves.

The Modern Understanding: The Role of the Oral Microbiome

Recent advancements in microbiology and dental research have revolutionized our understanding of cavities. Today’s science emphasizes the significance of the oral microbiome—a complex ecosystem of microorganisms residing in the mouth

While it is true that bacteria like Streptococcus mutans play a role in the development of cavities, the presence of these bacteria alone does not determine an individual’s susceptibility to tooth decay

The oral microbiome is highly individualized and influenced by numerous factors, including genetics, diet, oral hygiene practices, and even overall health. This personalized ecosystem means that two individuals with the same bacterial strains might experience different outcomes regarding dental health. 

For example, a person with a diet high in sugars and poor oral hygiene may be more prone to cavities despite having the same bacterial presence as someone with better oral care and a balanced diet.

Saliva Transfer vs. Pathogen Transmission

Understanding the difference between acquiring bacteria through saliva transfer and contracting infections via pathogens is key to appreciating the modern perspective on cavities. 

Unlike contagious diseases, where pathogens like viruses or bacteria invade and multiply within the host to cause illness, the bacteria involved in cavities are typically already present in the oral microbiome

The mere presence of these bacteria, transferred through saliva, does not directly cause cavities. It is the frequent consumption of sugars and fermentable carbohydrates that fuels these bacteria, leading to acid production and, subsequently, tooth decay.

The Bottom Line

According to our dentist in Homewood, this shift in understanding highlights the importance of lifestyle factors over the simplistic notion of bacterial transmission. Frequent sugar consumption creates an environment where acidogenic bacteria thrive, lowering the pH in the mouth and demineralizing tooth enamel. 

This process underscores that cavities are largely a preventable condition, manageable through proper diet and oral hygiene rather than avoidance of bacterial transmission.

Have questions? Ask a five-star dentist in Homewood, IL!

At Signature Smile Arts, we strive to give you the latest, most accurate information about your oral health. So, if you have a question about your teeth or gums, let us know! You can request information and appointments with Dr. Alex Shore here, or ring our front desk at (708) 799-5353 for more!

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18114 Gottschalk Ave.
Homewood, IL 60430-2208


Monday: 9:00 AM - 6:00 PM
Tuesday: 9:00 AM - 6:00 PM
Wednesday:   7:00 AM - 1:00 PM
Thursday: 9:00 AM - 5:00 PM
Friday: 9:00 AM - 3:00 PM
Saturday: By Appointment
Sunday: Closed

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