When should I brush my teeth? Before or after breakfast?

Many patients ask the question, "When should I brush my teeth in the morning? Before or after breakfast?"

Dental decay results from the fermentation of food debris by the dental plaque to produce acids that lead to the breakdown of teeth and form cavities. This acid response is present for up to an hour after the food is eaten generally until the salvia in the mouth neutralises this to normal levels.

Fluoride prevents dental decay by preventing the demineralisation or softening of the hard tooth substance and promoting its remineralisation or hardening of the mineral content of the teeth. Teeth are in a constant cycle of demineralisation and remineralisation depending on the presence of acids and saliva in the mouth.

Demineralising acids produced by bacteria that metabolise food or those ingested in the form of foods or drinks such as fruit juices are counteracted by the remineralising effects of saliva and fluoride in the mouth.

When brushing teeth before breakfast this build up of dental plaque is minimised thereby reducing the possible acid response from the oral bacteria when they metabolise the foods eaten at breakfast. In addition to that brushing with a fluoride toothpaste prior to breakfast means that there is plenty of fluoride within the mouth to prevent demineralisation and promote remineralisation of the enamel and dentine of the teeth at a time when it has maximum impact assuming the mouth was no rinsed out with water after the brushing of the teeth.

However, brushing the teeth after breakfast means that the response of the oral bacteria to the metabolism of the food and their production of acids has already taken place and the teeth have already been softened by the drop in pH in the mouth to acidic levels below 5.5 which  is termed the critical pH where it is proven that dental tissues are demineralised or softened.

By brushing after breakfast the loss of tooth substance by erosion from acidic levels is further enhanced by tooth brush and acid abrasion where the tooth substance is simply abraded away much faster as it is already softened by the acid. The presence of fluoride in the toothpaste will not be enough to prevent the demineralisation of the teeth and will not help promote remineralisation.

Gabby's advice:

From a scientific point of view it’s better to brush at least two minutes before breakfast with a fluoride toothpaste but I also tell my patients to consider rinsing their mouths with water after breakfast to get rid of the food debris left behind so that it doesn’t stay on the teeth all day. This flushing action further reduces the effect of acid on the teeth thereby returning the pH of the mouth to normal levels quicker.

After breakfast is also a good time to consider the use of a fluoride rinse which will further promote the remineralisation or hardening of the teeth at a time when it can stay of the teeth for a long period before any more food or drink is consumed later on in the day.

About Gabby:
I'm the dental hygienist at Peppermint Dental Centre in Wymondham