FREE NBDE Knowledge Questions and Answers
Which virus is associated with Forchheimer's sign?
Rubella. Rubella (German Measles) is a mild viral illness that is produced by a togavirus. Oral lesions, known as Forchheimer’s sign, have been reported to be present in about 20% of the cases. These consist of small, discrete, dark-red papules that develop on the soft palate and may extend onto the hard palate. This enanthem arises simultanesouly with the rash, becoming evident in about 6 hours after the first symptoms and not lasting longer than 12 to 14 hours. Palatal petechiae also may occur.
What happens when dental plaque adheres securely to the tooth's surface?
Carious lesions develop when dental plaque adheres firmly to the tooth's surface. The consumption of refined carbohydrates by bacteria results in dangerous lesions. Byproducts from these carbs raise acid levels, which lower pH values. Saliva, the body's natural defense against carious lesions, is aided by fluoridation.
What is the most common form of gingival disease?
Gingivitis that is associated with dental plaque formation is the most common form of gingival disease. Gingivitis has been previously characterized by the presence of clinical signs of inflammation that are confined to the gingiva and are associated with teeth showing no attachment loss. Gingivitis also has been observed to affect the gingival of periodontitis-affected teeth that have previously lost attachement but have not received periodontal therapy to stabilize any further attachment loss.
What salivary gland disorder would you suspect with your patient who suffers from keratoconjunctivits sicca and xerostomia?
Sjogren syndrome. Sjogren syndrome is a chronic, systemic autoimmune disorder that princiapply involves the salivary and lacrimal glands, resulting in xerostomia (dry mouth) and xeropthalmia (dry eyes). The effect on the eye often are called keratoconjuctivits sicca, and the clinical presentation of both xerostomia and xerophthalmia is also sometimes called sicca syndrome. Primary Sjogren syndrome is when there is no other autoimmune disorder present. Secondary Sjogren syndrome is when the patient manifests sicca syndrome in addition to another associated autoimmune disease. Although rheumatoid arthritis is the most common associated disorder with secondary Sjogren syndrome, it would not be originally suspected in this scenario.
What theory includes the increased fluid in tooth tubules, which deforms pulp nerve terminals and causes pain response?
Increased fluid in tooth tubules that deform pulp nerve endings and lead to a pain response is a component of Hydrodynamic Theory. Additionally, Hydrodynamic Theory argues that cold increases the pain stimulus.
The zona glomerulosa is responsible for:
The synthesis of aldosterone is carried out in the zona glomerulosa of the adrenal gland (b). This is the outermost of the three-layered cortex. The inner two layers of the adrenal cortex are the zona fasciculata and zona reticularis; these zones are responsible for the synthesis of cortisol (c), and adrenal androgens (a). The synthesis of ACTH or adrenocorticotropic hormone is done in the pituitary gland. This ACTH then acts on the adrenal glands to stimulate cortisol production by the zona fasciculata and zona reticularis.
A patients X-rays revealed lesions located on the substantia nigra portion of his brain. Which of the following disease may this patient be diagnosed with?
The substantia nigra is a part of the brain structure that plays a role in movement, addiction, and reward. Usually patients with Parkinson’s disease will have lesions that are located in the substantia nigra and their dopaminergic neurons destroyed. REFERENCE: Costanzo, Linda. S. Physiology: Fifth Edition. Board Review Series. Copyright 2011
What dental plaque organism is discovered first while making an early diagnosis?
The earliest dental plaque organism found is Streptococcus sanguis when attempting early diagnoses. Orally, Streptococcus sanguis prevents other strands of cavity causing Streptococcus from enamel attachment. However, during oral surgery or dental cleaning, it can enter the bloodstream, where it can live in heart valves, leading to endocarditis. Antibiotics are prescribed several days pre- and post- surgery to prevent endocarditis. Streptococcus sanguis is rarely in the saliva or the throat.
What promotes remineralization and has antibacterial qualities?
Saliva offers antimicrobial properties and carries minerals that aid in the remineralization process, clean food away, and provide antimicrobials.
Which of the following systematic diseases is not associated with aphthous-like ulcerations?
Irritable bowel syndrome is not associated with apththous-like ulcerations. It is characterized by abdominal pain or discomfort and has no known organic cause. Inflammatory bowel disease, however, is associated with aphthous-like ulcerations. Behcet syndrome (Choice B) is a multisystem disorder that affects the oral cavity in almost all cases. The oral lesions are aphthous-like in appearance, but are often larger and more numerous than those found in healthy individuals. Aphthous-like ulcers are often seen in patients with celiac disease (Choice C). Celiac disease is caused by a reaction to gliadin, a protein found in wheat. IgA deficiency (Choice D) is associated with apthous-like ulcerations. Nutritional deficiencies (Choice E), such as iron, zinc, B1, B2, B6 and B12, are associated with aphthous-like ulcerations. REFERENCE: Neville, B. W. (2009). Oral and Maxillofacial Pathology (3rd Ed.). St. Louis, MO: Saunders, an imprint of Elsevier Inc
Fluoridation can help to reduce the prevalence of caries. What age group is this especially true for?
Fluoridation can help to reduce the prevalence of caries. This is particularly true for youngsters since they often consume more sugar, produce more saliva, and have more space between their teeth, all of which help the fluoridation process.
What is a common ingredient in soft drinks, gum candy, toothpaste, breath fresheners, dental floss that often causes contact stomatitis?
Flavoring. It is usually cinnamon flavoring that causes these reactions. Mucosal abnormalities secondary to the use of artificially flavored cinnamon products are fairly common, but the range of changes was not widely recognized until the late 1980’s. Cinnamon oil is used as a flavoring agent in confectionery, ice cream, soft drinks, alcoholic beverages, processed meats, gum, candy, toothpaste, breath fresheners, mouthwashes, and even dental floss. Concentrations of the flavoring are up to 100 times that in the natural spice. The reactions are documented most commonly in those products associated with prolonged or frequent contact, such as candy, chewing gum, and toothpaste.
What is the resting membrane potential of a cell that is in state of domancy?
The resting membrane potential of a cell that is inactive is -70 mV. This is usually measured by the diffusion potentials of ions that try to achieve equilibrium potential.
What caries is caused by common cariogenic bacteria like Streptococcus mutans and Lactobacilli?
Streptococcus mutans and Lactobacilli are common cariogenic bacteria found in coronal caries. Streptococcus mutans use sucrose to generate a sticky polysaccharide that adheres to tooth’s surface. Additional sugars digested by Streptococcus mutans such as fructose, glucose, and lactose produce lactic acid. Lactobacilli often live in the digestive track and vagina symbolically; however, it increases oral acidity, thus working in concert with Streptococcus mutans. Fluoride can reduce the total number of Lactobacilli.
Which of the following is the most common type of occlusion in a normal dentition?
A heterotrimeric protein composed of three individual peptide chains describes:
Collagen (c) is an abundant human protein that in monomeric form assumes a left-handed, a-helical tertiary structure. Another way to describe this type of protein is a heterotrimeric protein composed of three individual peptide chains. When collagen monomers interact, they link to form a triple-stranded, right-handed super helical quaternary structure. Hemoglobin (a) is a tetrahedral group of two sets each of a-globin and ?-globin subunits, creating a quaternary structure. It is an oxygen transport protein. Myoglobin (b) is an oxygen storage protein, composed of loops connecting eight a-helices. Elastin (d) is an elastic protein found in connective tissue, and it mainly acts as cross-linked protein with monomers of the elastin molecule tropoelastin. REFERENCE: Baynes, John W. Medical Biochemistry, 3rd Edition. Mosby Ltd., 2009. Chapters 5 & 28.