Bruxism is an involuntary movement disorder characterised by excessive clenching and grinding of the teeth. It can occur when a person is asleep, known as sleep bruxism, or awake, referred to as awake bruxism.
Symptoms include headache, neck and jaw pain, or dental symptoms such as cracked teeth, damaged dental restorations such as broken crowns, and sensitive or sore teeth.
Some also present with symptoms of temporomandibular joint disorder such as reduced opening of the mouth, pain on opening, locked jaw and joint sounds such as clicking or crepitations on opening and closing of the mouth.
Dentists said bruxism is caused by physical, psychological and genetic factors.
Stress and anxiety are also highly associated with bruxism, said Dr Marilyn Loui, a dentist at Smile Central Clinic.
“The effects of suppressing emotions and motor activities results in several neuromuscular disorders. Chronic stress and the reactions triggered by it causes functional deficiencies of the nervous-muscle system (leading to bruxism),” said Dr Loui.
The stress brought about by the Covid-19 pandemic has also led to an increase in bruxism.
Dr Lynette Ng, dental director at The Dental Studio, said: “Stressful situations activate the sympathetic pathways in a fight or flight response causing jaw muscles to increase in tonicity, thus the clenching of teeth. Stress can also keep people awake at night, and insomnia or poor sleep patterns have been associated with worsening bruxism at night.”
Ms Chau said the pain in her jaw could have been “exacerbated” by the anxiety she has felt due to the pandemic. “The pain only became intense four months ago, so it could be due to the stressors from Covid-19. I’m anxious because nobody anticipated such an outbreak and there is uncertainty as to how long this will go on for.”
Dr Chua Ee Kiam, senior consultant at the National Dental Centre Singapore’s Department of Restorative Dentistry, Prosthodontic Unit, said changes in the job landscape, adjustments to new working environment, disruption to social activities and the fear of Covid-19 infection can cause an increased level of mental activity that may not be well addressed.
“The mind-processing activities often continue in the subconscious mode, during sleep, triggering jaw muscle activity,” he said.
The National Dental Centre sees about 30 patients a month for bruxism and Dr Chua is expecting the number to rise due to the higher stress and anxiety levels during this period.
The number of patients with bruxism has increased by about three to four times at The Dental Studio since the end of the circuit breaker, noted Dr Ng, a prosthodontist.
She now sees three to four patients a week with pain related to bruxism or requesting mouthguards as their old ones have been worn out.
She also reported an increase in the number of patients with fractured teeth that required extractions, root canals or crowns.
Bruxism can also occur in an individual if a family member suffers the same problem. A high intake of alcohol and caffeine, and medication such as antidepressants and certain illegal drugs can also increase its occurrence.
Most people are not aware that they grind their teeth when they sleep, but become aware of the pain or its impact when they wake up with a headache or sore jaw muscles. “The grinding forces can be as high as 80kg,” said Dr Ng.
People may also learn about it when their sleep partners complain of the jarring sound of teeth gnashing together.
“The episodes can be transient, lasting a few seconds, and can range up to 100 episodes a night. Teeth grinding also varies significantly over time and may appear at certain periods of our lives, disappear and, for some, only to reappear again.
“As such, more than 80 per cent of bruxers are unaware they have this problem,” she added.
Though bruxism cannot be cured, it can be managed through certain lifestyle adjustments.
Dr Loui said treatment for bruxism usually begins with an improvement to one’s sleep pattern, reducing the intake of coffee, quitting smoking and limiting physical or mental activity before going to bed.
Apart from wearing a mouth guard to reduce the damage to the teeth and jaw during grinding and clenching, pain medication can also help relieve the symptoms.
Dr Chua advised those with the condition to exercise regularly to try to reduce stress levels.
However, he added: “Teeth wear and damage occur over a period of time and often patients see us only when the damage is extensive. A check with the dentist is a good start.”
There is no cure for involuntary teeth grinding and clenching, known as bruxism. However, several approaches can decrease episodes and limit damage to the teeth and jaw.