Sleep bruxism has a strong association with gastroesophageal reflux disease, independent of stress, age, sex, or body mass index. The results of this preliminary study indicate an interesting direction in investigating the common biological pathways between these 2 entities. Mengatto JPD 2013

OSA has a strong association with GERD, and GERD with nocturnal bruxism. Hesselbacher 2014 ORMJ

Sleep Bruxism

Sleep Bruxism is the grinding or clenching of teeth during sleep, which is preceded by sleep arousals. Sleep Arousal is a naturally occurring 3-10 second shift occurring during deep sleep, which is accompanied by an increase in muscle tone. This motor activity causing clenching and grinding activity of jaw muscles is believed to be an attempt to open the constricted airway. Sleep bruxism occurs in multiple episodic bursts throughout the night. Some episodes may produce audible grinding noise.

Incidences of Sleep Bruxism is higher in children and then decreases with age. It is found in 8 percent of the general population and 14-20 percent of children. A constricted airway due to Adenoid and tonsil hypertrophy is often the cause for a constricted airway in children, which opens up with age.

Obstructive Sleep Apnea (OSA) is characterized by frequent episodes of stopped or very shallow breathing, each lasting 10 seconds or more. It’s caused by an obstruction of the upper airway because of inadequate motor tone of the tongue and/or airway dilator muscles. Diagnosis usually requires overnight polysomnography to detect the frequency of apnea (stopped breathing) and hypoapnea (very shallow breathing) events. The apnea-hypoapnea index (AHI) is the average number of disordered breathing events per hour. Typically OSA syndrome is defined as an AHI of five or greater with associated symptoms (e.g., excessive daytime sleepiness, fatigue, etc.) or an AHI of 15 or greater, regardless of associated symptoms.  Increased muscle tone and micro arousals caused by sleep apnea events are the trigger factors for sleep bruxism [3].

Mandibular advancement splint (MAS) works well for helping those with OSA. Mostafiz 2019 AJO They also appear to help type 2 diabetes patients lower HbA1 levels. However, there is selection bias here as anyone in this experiment is likely doing other things to help themselves as well as no control. Baslas JPros 2019. There are some risks to this treatment, such as jaw/bite changes and pain.

Obtrusive sleep apnea in children

Proper sleep is obviously very important for growing children. Normal sleep cycle includes rapid eye movement (REM) and non-REM sleep. Non-REM has 3 stages from light to deep sleep. With sleep apnea the brain is struggling to get oxygen and does not get to REM or deep levels of non-REM.

Top signs to look for in children with sleep apnea

There is a BEARS sleep screening questionnaire that someone can take.

• High and narrow palatal vault
• Mouth breathing
• Clenching or grinding and tooth wear
• Enlarged tonsils and adenoids
• Allergic rhinitis or prevalence of allergy symtpoms
• Tongue tie or lip tie
• Maxillary and mandibular deficiency

If these are present then questions to ask the parents are:

• Does your child snore?
• Do they stop breathing for short periods of time when sleeping? Parents can watch for 20 minutes to determine this.
• How rested does your child seem upon waking?
• Any behavior issues at home or school? Especially fidgeting, emotional outbursts and short attention spans.

What are the symptoms in children with sleep apnea?

There are both physical and behavioral characteristics. Behavioral characteristics include the following:

• Snoring
• Hyperactivity – attention deficit disorder
• Behavioral challenges
• Trouble focusing
• Bed-wetting
• Learning disorders
• Impaired growth
• Tendency towards aggressive behavior
• Anxiety disorders

Physical signs result from the body struggling to get air. The main change is the kids will be doing more mouth breathing and this impacts growth. Changes include the following:

• High palatal vault
• Narrow arch form
• Anterior open bites
• Mouth breathing
• Long and narrow faces
• Habitual open mouth
• Venous pooling, especially under the eyes

Treatment for children with sleep apnea

All treatments are meant to give more breathing room. Some kids will simply grow out of it as they get bigger, some will not.

• Adenotonsillectomy
• Oral myofunctional therapy
• Orthodontics
• Positive airway appliance

GERD is characterized by leak of stomach contents into the esophagus. Typical symptoms are heartburn and regurgitation (the perception of gastric contents moving from the stomach into the
esophagus).  Sleep Apnea episodes are often implicated as a contributing etiology of GERD and SB. Increased negative pressure in intra thoracic space during apneic episode causes gastric
acid expelled into the esophagus. This triggers microarousals leading to Sleep Bruxism.

References:
1. Rouse, Jeffrey S. “The Bruxism Triad.” Inside Dentistry (2010): 32-44.
2. Park, John G., Kannan Ramar, and Eric J. Olson. “Updates on definition, consequences, and management of obstructive sleep apnea.” Mayo Clinic Proceedings. Vol. 86. No. 6. Elsevier, 2011.
3. Miyawaki, Shouichi, et al. “Association between nocturnal bruxism and gastroesophageal reflux.” Sleep New York Then Westchester- 26.7 (2003): 888-892.