PH of the Mouth – Part Two

Let’s take a closer look at the bacteria within plaque
It may be beneficial to re-read the last blog before reading this one.

Plaque is made up of bacteria that are acid and non-acid producers…also known as non-healthy and healthy bacteria.

The healthy bacteria in plaque can tolerate brief periods of low pH. They are however inhibited from growing and are ‘killed off’ by prolonged exposure to low pH or frequent acid attacks.

Exposure to long periods of low pH will result in increased growth (or colonization) of acid producing bacteria. This will in turn result in an increased risk of tooth decay and erosion.

Important: If dental plaque is kept at a pH of 7 or greater, the overall bacterial species will not be acidogenic. So, even if the teeth are exposed to carbohydrates (sugar), since the bacteria are not of the acid producing type, the sugar will not be broken down into acids.

The goal: To maintain the mouth at a neutral or alkaline pH. We need to keep the healthy bacteria around and promote their growth. All efforts have to be made to prevent a shift to the unhealthy or acid producing bacteria. This goal is called pH Neutralization; preventing a bacterial shift. PH neutralization is a treatment strategy that can be used for all age groups including infants.

Consider this scenario
An individual who eats and drinks a lot of sugary substances and doesn’t practice optimal oral hygiene and yet still doesn’t get cavities: The explanation for this may be that the individual’s oral cavity is at a healthy or neutral pH.

Now consider the opposite scenario. One who maintains good home care, has a healthy diet, but gets their fair share of cavities. The explanation could be that they have a low salivary pH which consists of acidogenic or cavity causing bacteria. These individuals are susceptible to small changes in pH.

There is hope
It is possible for an individual in the latter group, to reverse the situation in favour of healthy bacteria. This can be achieved through a process known as Alkaline pH Dental Therapy or pH Neutralization Therapy. For those prone to decay, this involves the use of alkaline dental products (rinses or tray/gel systems) with pH ranges of between 8 and 11. These products can reverse the cavity-causing bacteria to the healthy type.

For those who are susceptible, the goal is pH neutralization when eating food that is high in sugar: In other words, shifting the bacterial balance to the healthy type that won’t act on sugar to produce acids.

The following is an important concept: To keep the oral environment in a healthy state it is preferable to keep the bacterial balance healthy. It seems like common sense, however, this is easier to achieve than having to reverse an acidic environment (biofilm) to a healthy one.

The ideal pH for the prevention of decay is 8-9 and the ideal pH for the treatment of an unhealthy biofilm is 9-11.

In the next blog, we will revisit the effects of acid reflux on the oral cavity…until then!

Yours in good oral health,

Dr. F. Keshavarz Dentistry, Brampton Dentist

For any dental questions or concerns, please give us a call today @ 905.791.3867…you’ll be glad you did!

Based in Brampton, Ontario, Brampton Dentist Dr. F. Keshavarz Dentistry has been practicing gentle and pain-free dentistry for over two decades. During this time, they have helped to improve the dental health of countless satisfied patients in Peel Region, Brampton and beyond!

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In the last blog, we looked at what we need to do when a primary

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