Are Sleep Bruxism, Sleep Fragmentation and Flow Limitation Connected?
Recently I have been attending Henry Schein Dental Sleep Complete meetings, presenting the Nox T3 home sleep study device by Carefusion. Part of the weekend includes several of the dentists and their staff taking a home sleep test including cheek EMG to evaluate sleep bruxism.
Our goal in these teaching moments is to provide a real world view of the patient experience. The participants in these courses actually mirror the average patient population in a dental office very well. They are generally healthy and consider themselves asymptomatic for sleep disorders. Once we start discussing symptoms and running through the questionnaires the discussion that ensues is generally around snoring and sleep quality.
The direct connection between upper airways resistance, sleep fragmentation, sleepiness and bruxism is a very clear and present opportunity for the dental practitioner. As we have patients fill out Stop Bang and Epworth Questionnaires the discussion in most cases becomes one of sleep quality. Most of the attendees believe that they can sleep better. If we look at the average AHI of the almost 150 studies we have done in the last 4 courses it is somewhere around 4.75. What is striking is that since we are tying sleep bruxism in to the home sleep test. The average Bruxism event count is around 500 with the high end in the 1500 to 2600 events per 7 hour sleep test. We have only been keeping casual count, however it appears that 85 to 90% of the patients that present are wearing bite guards to protect their teeth at night from grinding.
It is interesting to me the amount of flow limitation I have seen in these 150 studies, Sleep fragmentation, RERA’s and flow limitation combine for a diagnosis of UARS (upper airway resistance syndrome). Are the patients with high flow limitation index complaining of sleepiness? The answer is yes.
The excerpt below from a Nox T3 by Carefusion study below, was collected on a patient whose AHI was 1.5. While the patient complained of snoring and some sleepiness it is unlikely that any medical treatment could be ordered with this low of an AHI. While the patient below did not present with a high Epworth score, there was a complaint of daytime sleepiness and the patient wore a mouth guard for sleep bruxism. The Nox T3 study below showed that 22% of the night the patient showed flow limitation. Significant sleep fragmentation was indicated due to the movement that was scored as well as the body position measurements indicating an almost even distribution throughout the night. As to the patient’s bruxism, the patient had 1968 bruxism bursts in a total of 7hrs and 14 minutes of sleep.
Following, is an image of all of these conditions in a single 2 minute segment from a sleep study.
Questions to consider and discuss
Did the dental team in this case identify a patient whose Bruxism is related to RERA activity?
Is UARS a condition that often leads to more serious conditions like OSA?
Should a dentist test a patient for UARS and Bruxism to help guide his/her choices in treating the patients dental condition?
Should the dentist consider changing the patient to a double arch splint like a Herbst appliance? This would increase vertical dimension and anteriorize the mandible to support the airway while at the same time protecting the patients dentition?
more info on this device Nox T3 medical grade home bruxism monitor.