ABDSM FOCUST MEDICAL STUDY GUIDE UPDATED 2026/2027 SYLLABUS Introduction to Dental Sleep Medicine

Screening & Diagnosis What is the most commonly used patient-reported questionnaire for screening OSA risk? ANSWER The STOP-BANG questionnaire is highly prevalent, especially in surgical and dental settings. The Epworth Sleepiness Scale (ESS) is also widely used to quantify daytime sleepiness. A patient with an Epworth Sleepiness Scale (ESS) score of 18 is considered to have what level of daytime sleepiness? ANSWER An ESS score of 18 indicates severe excessive daytime sleepiness. (Scores: 010 = normal, 11-15 = mild, 16-20 = moderate, 21-24 = severe). What is the purpose of a home sleep apnea test (HSAT)? ANSWER A HSAT, or Level III sleep study, is used to diagnose OSA in patients with a high pre-test probability of moderate to severe OSA, without significant comorbidities. It is not suitable for screening asymptomatic populations. Which physical finding is most strongly associated with an increased risk of OSA? ANSWER Increased neck circumference (>17 inches in men, >16 inches in women) is a strong predictor. Other key findings include BMI >35, craniofacial abnormalities, and a Friedman tongue position of III or IV. What is the "Respiratory Arousal Threshold" and how does it relate to OSA? ANSWER It is the level of respiratory effort required to cause an arousal from sleep. A low threshold means a patient wakes up too easily, preventing them from reaching stable sleep, while a high threshold can allow severe oxygen desaturation to occur before waking. Name two common oral conditions that must be treated before taking OAT impressions. ANSWER Active periodontal disease and extensive untreated dental caries. What is the potential consequence of over-advancing the mandible with a MAD? ANSWER Significant TMJ pain, muscle tenderness, and potentially irreversible condylar displacement or disc derangement. How does weight loss impact OSA severity? ANSWER Weight loss can significantly reduce the severity of OSA (lower AHI) by decreasing fat deposition in the tongue and soft tissues of the pharynx, thereby enlarging the airway. What is the role of a Sleep Physician in the context of OAT? ANSWER To diagnose OSA, determine that OAT is a medically appropriate treatment, and provide ongoing medical oversight, including ordering follow-up sleep studies to verify efficacy. What is the definition of "PAP Intolerance"? ANSWER The inability to use PAP therapy consistently despite multiple interventions (mask fittings, pressure adjustments, etc.), typically defined as usage of <4 hours per night on 70% of nights. What is the "AASM" and what is its role? ANSWER The American Academy of Sleep Medicine. It establishes clinical guidelines and standards for the diagnosis and treatment of sleep disorders, including the use of OAT. What is the purpose of a "Herbst" mechanism on a MAD?  The Herbst mechanism is a rigid, telescoping mechanism that allows for controlled protrusion and is commonly used in titratable MADs due to its durability. Why is a patient with significant periodontal disease a poor candidate for OAT? ANSWER The forces exerted by the appliance on the teeth can accelerate the progression of periodontal bone loss and lead to tooth mobility. What is the difference between a "Custom" and a "Prefabricated" OAT? ANSWER A custom OAT is fabricated on models of the patient's teeth from dental impressions, providing optimal fit, retention, and comfort. A prefabricated ("boil andbite") device is not custom-made and is not considered the standard of care. What is the "Friedman Tongue Position" classification? ANSWER A clinical staging system (I-IV) that assesses the size of the tongue relative to the oropharyngeal inlet, with higher stages indicating greater obstruction and OSA risk. What is the significance of a "Centric Relation" record in OAT fabrication? ANSWER It records a stable, reproducible, and physiologically sound position of the condyles in the glenoid fossa, serving as a reference point for constructing the appliance and monitoring occlusal changes. What information should a dentist provide to a patient's primary care physician about successful OAT treatment? ANSWER The final protrusive position, the results of the follow-up sleep study showing efficacy, the patient's reported symptomatic improvement, and the plan for long-term maintenance. What is the Mallampati classification, and how is it relevant to dental sleep medicine? ANSWER The Mallampati classification assesses the oropharyngeal space based on the visibility of structures like the uvula and soft palate. A higher class (III or IV) indicates a more restricted airway and is a risk factor for OSA. What is the difference between an apnea and a hypopnea? ANSWER An apnea is a ≥90% reduction in airflow for ≥10 seconds. A hypopnea is a ≥30% reduction in airflow for ≥10 seconds associated with a ≥3% oxygen desaturation and/or an arousal from sleep. According to AASM guidelines, an AHI of 25 would be classified as what severity of OSA? ANSWER Severe OSA. (Normal: AHI <5; Mild: AHI 5-15; Moderate: AHI 15-30; Severe: AHI >30). What is a Respiratory Effort-Related Arousal (RERA)? ANSWER A RERA is a sequence of breaths lasting ≥10 seconds characterized by increasing respiratory effort leading to an arousal from sleep, but one that does not meet the criteria for an apnea or hypopnea. What is the RDI (Respiratory Disturbance Index)? ANSWER The RDI is the average number of apneas, hypopneas, and RERAs per hour of sleep. It can be a more comprehensive metric than the AHI, especially in patients with Upper Airway Resistance Syndrome (UARS). Why is it critical for a physician to establish a diagnosis of OSA before initiating Oral Appliance Therapy? ANSWER It is a medico-legal and ethical standard. The physician confirms the diagnosis, rules out other sleep disorders, determines the severity, and establishes that OAT is an appropriate treatment. The dentist then provides the therapy under a physician's supervision.  Oral Appliance Therapy (OAT) 16. What is the most common type of oral appliance used for treating OSA? ANSWER The Mandibular Advancement Device (MAD) is the most common and widely studied type of OAT. How does a Mandibular Advancement Device (MAD) work? ANSWER A MAD mechanically protrudes and stabilizes the mandible in a forward position, which pulls the tongue and suprahyoid muscles forward, thereby increasing the cross-sectional area of the retropalatal and retroglossal pharynx and preventing collapse. What is the primary mechanism by which a Tongue Retaining Device (TRD) works?