Teeth-grinding among teenagers while sleeping may indicate they could have experienced bullying in school, a new study suggests.

In sleep bruxism, people either clench or grind their teeth in deep slumber. It is a sleep-related movement disorder which may also trigger other sleep disorders such as snoring and pauses.

A new Brazilian study published in the Journal of Oral Rehabilitation suggested that sleep bruxism could be a sign of verbal bullying, according to researchers from the University of Padova, Italy and Universidade Federal de Minas Gerais and Universidade Federal de Goias, Brazil.

The study observed 103 adolescents - aged 13 to 15 years old - from the case group and 206 adolescents with the same age in the control group.

The case group had possible sleep bruxism (self- or parent-reported), while the control group reported no (possible) sleep bruxism.

The groups completed a questionnaire based on the National School of Health Research (PenSe), which quizzed them on their involvement in school-based verbal-bullying.

The participants were likewise evaluated based on their economic class using a criteria taken from the Brazilian Association of Research Companies.

It was found that nearly half of the participants were involved in verbal school bullying or 43.3 percent, and majority of them were males at 90.3 percent.

"Adolescents with possible SB were more likely to have been involved in episodes of verbal school bullying," the researchers wrote. They also added that based on their findings, "it can be suggested that possible SB in young teenagers is associated with a history of episodes of verbal school bullying," according to the paper.

Sleep bruxism, according to the United Kingdom's National Health Service (NHS), is related to stress and anxiety.

May people may be unaware of their sleep habits but its symptoms include facial pain, headaches, earache, stiffness in the jaw joint, disrupted sleep, and broken or worn-down teeth. 

Patients who talk while sleeping, behave violently while sleeping, experience sleep paralysis and experience hallucinations, and are likely to grind their teeth while sleeping. MIMS

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