For many dental professionals, dental sleep medicine is still a relatively new and sometimes overwhelming topic, especially when it comes to the terminology and abbreviations. It’s almost like you are speaking a different language.

For those moments when you do feel overwhelmed, we’ve created the ultimate glossary of dental sleep medicine terms and abbreviations.

Whether you’re new to dental sleep medicine or you just want to brush up on your dental sleep knowledge, check out the following roundup of dental sleep terms to keep yourself in the loop.

Apnea – A general term used to describe a deduction or cessation of breathing while asleep

Apnea Event – Respiratory event lasting 10 seconds or longer with a greater than 50% decrease in airflow

Apnea Hypopnea Index (AHI) – A calculated total of events including apnea, hypopnea, mixed apnea and central apnea

Bruxism Burst Index (BBI) – The total number of EMG bursts per hour

Bruxism Episode Index (BEI) – The total number of scored clenches, grinds, and RMMA divided by total sleep time

Central Apnea – An event lasting greater than 10 seconds with an absence of respiratory effort

Continuous Positive Airway Pressure (CPAP) – A treatment that uses mild air pressure to keep the airways open

Cyclic Alternating Patterns (CAP) – A long lasting periodic activity consisting of two alternate electroencephalogram (EEG) patterns usually related to level of arousal

Fee For Service – A method of reimbursement by which the dentist establishes and expects to receive his/her full fee for the specific services performed

Gastroesophageal Reflux Disease (GERD) – A long term condition where stomach contents come back up into the esophagus, also known as acid reflux

Hypopnea Event – A 30 to 50% decrease in airflow with a 3 or 4% oxygen desaturation lasting 10 seconds or longer

Masseter Contraction (MC) – When the masseter muscle contracts through jaw clenching/unclenching

Mean Waking Bite Force (MWBF) – A calibration value measured in microvolts (uV) by asking the patient to bite (clench) down as hard as they can 5 times, relaxing between clenches. These 5 EMG bursts are measured and averaged

Mixed (Grind) – An EMG burst characterized by grinding teeth

Mixed Apnea – Event lasting 10 seconds or longer where there is an absence of respiratory effort for greater than 3 seconds, then respiratory effort resumes and there is no airflow

Obstructive Apnea (OA) – Temporary cessation of airflow caused by a collapse of the airway either full or partial without an accompanying cessation of respiratory effort

Obstructive Sleep Apnea (OSA) – Obstructive apnea while sleeping

Oxygen Desaturation Index (ODI) – The number of oxygen desaturations of 3 or 4% per hour of sleep measured by an oximeter

Phasic, Rhythmic Masticatory Muscle Activity (RMMA) – An EMG burst characterized by muscle twitching

Polysomnography (PSG) – A type of sleep study using a multi-parametric test used by most sleep labs

Respiratory Event Related Arousal (RERA) – A sequence of breaths characterized by increasing respiratory effort leading to an arousal from sleep, but does not meet the criteria for apnea or hypopnea

Rhythmic Jaw Movement (RJM) – Involuntary repetitive jaw movements

Snore Index (SNI) – Percent of time that someone has scored a patient as snoring. The time is added up and divided by total sleep time

Tonic (Clench) – An EMG burst characterized by teeth clenching

Underlying Snoring Criteria – Snoring 30% above ambient room noise