Dentosphere : World of Dentistry

 # Obstructive sleep apnea syndrome (OSAS) often results in all of the following except:  A. Excessive daytime sleepiness  B. Aggressive behavior  C. Personality changes  D. Depression  The correct answer is B. Aggressive behavior. Signs and symptoms Generally, symptoms of OSA begin insidiously and are often present for years before the patient is referred for evaluation. Nocturnal symptoms may include the following: Snoring, usually loud, habitual, and bothersome to others Witnessed apneas, which often interrupt the snoring and end with a snort Gasping and choking sensations that arouse the patient from sleep, though in a very low proportion relative to the number of apneas they experience Nocturia Insomnia; restless sleep, with patients often experiencing frequent arousals and tossing or turning during the night Daytime symptoms may include the following: Nonrestorative sleep (ie, “waking up as tired as when they went to bed”) Morning headache, dry or sor...

 # The most common mandibular surgical osteotomy to advance the mandible is ____.  A. Le Fort I osteotomy  B. Segmental maxillary osteotomy  C. Bilateral sagittal split osteotomy  D. Intraoral vertical ramus osteotomy  The correct answer is C. Bilateral sagittal split osteotomy. Bilateral sagittal split osteotomy (BSSO) is one of the most commonly performed and versatile mandibular procedures. It can be used for backward or forward correction of the mandible in isolation or in combination with a maxillary osteotomy. It is usually performed while the patient is under general anaesthesia. It was originally described by Trauner and Obwegeser in 1957. The procedure has since undergone numerous modifications, including those by Dalpont, Hunsuck, Bell and Epker. Even when there are large advancements, bone grafting is rarely required because of the long bony interface between the two fragments. Indications for BSSO include mandibular advancement, setback and...

 # Distraction osteogenesis is preferred over a traditional osteotomy:  A. When a large advancement is needed  B. When a small advancement is needed  C. When exacted interdigitation of the occlusion is needed  D. When the treatment needs to be done in a very short period of time  The correct answer is A.  When a large advancement is needed. Distraction osteogenesis is preferred over traditional osteotomies when large skeletal movements are required and the associated soft tissue cannot adapt to the acute changes and stretching that results. Larger movements may be at increased risk of some relapse; this is particularly true in a patient with a cleft palate, where there is significant soft tissue scarring from previous surgeries.

 # At which of the following locations are perikymata usually found? a. Cervix of the crown. b. Apex of the root. c. Cusp tips. d. Deposited throughout the crown. The correct answer is A. Cervix of the crown. Perikymata are transverse, wave-like grooves, believed to be the external manifestations of the striae of Retzius. They are continuous around a tooth and usually lie parallel to each other and to the cementoenamel junction. Ordinarily there are about 30 perikymata per millimeter in the region of the cementoenamel junction, and their concentration gradually decreases to about 10 per millimeter near the occlusal or incisal edge of a surface. Their course usually is fairly regular, but in the cervical region it may be quite irregular. The terms perikymata and imbrication lines are used without distinction to the surface structures of ridges or grooves. To avoid confusion in the usage of these terms it has been suggested that the terms perikymata or imbrication lines be suffixed b...

 # Bones that are small, irregularly shaped, and found along sutures are called  a. Parietal.  b. Wormian.  c. Temporal.  d. Zygomatic.  The correct answer is B. Wormian bone. Wormian bones, also known as intrasutural bones or sutural bones, are extra bone pieces that can occur within a suture (joint) in the skull. These are irregular isolated bones that can appear in addition to the usual centres of ossification of the skull and, although unusual, are not rare. They occur most frequently in the course of the lambdoid suture, which is more tortuous than other sutures. They are also occasionally seen within the sagittal and coronal sutures. A large wormian bone at lambda is often called an Inca bone (Os Incae), due to the relatively high frequency of occurrence in Peruvian mummies. Another specific Wormian bone, the pterion ossicle, sometimes exists between the sphenoidal angle of the parietal bone and the great wing of the sphenoid bone. They tend to vary i...

 # Which certification is required for dentists that provide general anesthesia?  a. Basic life support (BLS).  b. Emergency medical training (EMT).  c. Cardiopulmonary resuscitation (CPR).  d. Advanced cardiac life support (ACLS).  The correct answer is D. Advanced cardiac life support (ACLS). Dentists that provide general anesthesia must be certifed in ACLS for their licensure; BLS certifcation is inadequate. Many states mandate, and the current standard of care necessitates, certifcation in ACLS training for dentists providing general anesthesia.  ACLS: For healthcare professionals who either direct or participate in the management of cardiopulmonary arrest or other cardiovascular emergencies and for personnel in emergency response What does this course teach? Basic life support skills, including effective chest compressions, use of a bag-mask device, and use of an AED Recognition and early management of respiratory and cardiac arrest Recogniti...

 Which of the following is a property of biofilms and is of clinical signifcance? a. Facilitate stain formation. b. Increase sensitivity to antibiotics. c. Extremely tolerant of antimicrobial agents. d. Enhance the development of halitosis. The correct answer is C. Extremely tolerant of antimicrobial agents. The term biofilm describes relatively undefinable microbial community associated with a tooth surface or any other hard non-shedding material. Biofilms are ubiquitous and are found in oral cavity, the bottom of boats and docks, inside pipes, rocks in streams, catheters, hip and voice prosthesis and contact lenses. Biofilm bacteria exhibit stronger resistance (1000 to 1500 times) to biocides and antimicrobial agents than do their planktonic counterpart. Following hypothesis may help to explain the increased resistance to antimicrobials. 1. The exopolysaccharide of the biofilm matrix may inhibit the diffusion of antimicrobial agents. 2. The physiological differences among biofilm...

 # Herpes simplex type 1 virus can be transmitted in dentistry by which of the following?  a. Sharps injury.  b. Contact with skin.  c. Inhalation of infected droplets.  d. Contact of infected material with skin or eyes  The correct answer is D. Contact of infected material with skin or eyes. It is estimated that out of the 80 known herpes viruses, at least eight are known to infect human beings. The herpes viruses that are known to cause infection in humans are herpes simplex virus (HSV 1 and 2), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpes virus 6 (HHV-6), human herpes virus 7 (HHV-7) and human herpes virus 8 (HHV-8). These viruses are usually transmitted from host to host by direct contact or through saliva and genital secretions. Herpes viruses are shed in the saliva of asymptomatic hosts.

 # Which of the following structures are closely related in time of development and sometimes have related malformations?  a. Ear and tongue.  b. Palate and tongue.  c. Palate and face.  d. Face and ears.  The correct answer is C. Palate and Face. The human face develops early in gestation, during the fourth through seventh weeks, and the palatal processes begin to close during the eighth week. These two structures are closely related in time of development and sometimes have related malformations.  CLICK HERE FOR MORE MCQs

 # The condition involved with an unerupted tooth or impacted tooth is: A. Dentigerous cyst B. Mural ameloblastoma C. Adenomatoid odontogenic tumor D. All of the above The correct answer is D. All of the above. Dentigerous cyst is always associated initially with the crown of an impacted, embedded or unerupted tooth. A dentigerous cyst may also be found enclosing a complex compound odontoma or involving a supernumerary tooth. The most common sites of this cyst are the mandibular and maxillary third molar and maxillary cuspid areas. Adenomatoid Odontogenic Tumors are seen in a rather narrow age range, between 5 and 30 years, with most cases appearing in the second decade. Females are more commonly affected than males. Lesions often appear in the anterior portion of the jaws, more often in the anterior maxilla, generally in association with the crowns of impacted teeth. 

 # HSV-2 virus resides in: A. Basal ganglia B. Stellate ganglia C. Lumbosacral ganglion D. Otic ganglion The correct answer is C. Lumbosacral region. It is now well established that the HSV does not remain latent at the site of the original infection in the skin or oral mucosa. Instead, the virus reaches nerve ganglia supplying the affected areas, presumably along nerve pathways, and remains latent there until reactivated. The usual ganglia involved are the trigeminal for HSV-1 and the lumbosacral for HSV-2. Viral DNA can be demonstrated in these ganglia. Unfortunately, this incorporation of viral DNA into host DNA ensures a lifelong infection beyond the reach of antibody, cell mediated immune responses or chemotherapy.

 # The tongue of a patient deviates to one side whenever he sticks his tongue out. The cranial nerve that may be damaged is: A. Trigeminal nerve B. Vagus nerve C. Facial nerve D. Hypoglossal nerve The correct answer is D. Hypoglossal nerve. HYPOGLOSSAL NERVE Hypoglossal nerve is the twelfth cranial nerve. It supplies the muscles of the tongue. The hypoglossal nerve is tested clinically by asking the patient to protrude his/her tongue. Normally, the tongue is protruded straight forwards. If the nerve is paralysed, the tongue deviates to the paralysed side. 

 # Which of these is a pseudocyst? A. Nasolabial cyst B. Globulomaxillary cyst C. Traumatic cyst D. Radicular cyst The correct answer is C. Traumatic cyst. Traumatic cyst is also called as Solitary bone cyst, hemorrhagic cyst, extravasation cyst, unicameral bone cyst, simple bone cyst, idiopathic bone cavity. The traumatic cyst is a pseudo cyst (lacks an epithelial lining) and an uncommon lesion comprises about 1% of all jaw cysts. It occurs in other bones of the skeleton as well.