Did you know sleep bruxism or teeth grinding during sleep can be a red flag for breathing disturbances?
Episodes of teeth grinding commonly occur in the transition from deep sleep toward light or REM sleep.
They are associated with brief arousals lasting a few seconds where the brain, heart and breathing are reactivated and there is a rise in the muscle tone.
These episodes of increased jaw muscle activity are thought to offer some protection against the complete collapses of the airway that define Obstructive Sleep Apnoea (OSA).
New thinking is that rather than being related to psychological stress, teeth grinding can be a response to the physiological stress of the threat to breath.
A study by Australian dentist Dr Nisch Singh demonstrated that the degree of sleep bruxism related tooth wear in children’s teeth was associated with their Respiratory Disturbance Index (RDI) – a measure of their degree of OSA plus the more subtle breathing disturbances related to increased effort of breathing to maintain an open airway. The results of this study suggested that sleep bruxism was a marker for breathing disturbances, but there was a closer relationship with the effortful breathing than the complete collapses of the airway.
This means that it is important to pay attention to your child’s sleep and breathing, and be aware of other red flags that could indicate unrestorative sleep. This is a good link for more information.
If there are no other signs and symptoms of sleep breathing disturbance, then no intervention may be needed.
If there are any underlying breathing disturbances, these may be addressed.
One of the common risk factors for obstructive breathing in young children are enlarged adenoids and tonsils. Research tells us that approximately 75% of children who grind their teeth and have their adenoids and tonsils removed will stop teeth grinding. That leaves a quarter who will continue (Morton 2008, Efketkharian et al 2008).
We know that sleep breathing disturbances are multifactorial and removing of adenoids and tonsils is not curative for most children, particularly in the long term. These problems require a team approach.
A dentist with a special interest in airway will assess for other risk factors. For example in this child with severe tooth wear related to teeth grinding, we assess
- The palate – the deep “thumb-print” indent represents a narrowed nasal floor and airway with increased resistance to nasal airflow.
- Their oral rest posture – in this picture we see open mouth posture and a tongue thrust or lowered tongue posture. If a child has their lips apart during the day, we know that this will be the case at night when all the muscles are more relaxed. As the jaw drops open, it rotates backwards and so does the tongue, impinging the airway space.
- The way the tongue functions – optimal function includes the capacity for the tongue to suction to the palate - this is the most stable position for breathing and the airway during sleep. We assess for tongue control, tone and tongue ties that could be restricting this function.
What about sleep bruxism and medications?
There are also certain stimulant and anti-depressant medications where teeth grinding is a known side-effect.
It can still be helpful to rule out any underlying breathing disturbance. There is a growing evidence base suggesting an association between ADHD and mood disorders in children with obstructive sleep.
Ideally, it would be good to rule out any sleep breathing problems and unrestorative sleep before committing to long term medications.