Dentosphere : World of Dentistry

 # Endocrine disorder is the primary cause of: A. Acromegaly B. Albright’s syndrome C. Paget’s disease D. Fibrous dysplasia The correct answer is A. Acromegaly. Explanation: Acromegaly is primarily caused by an endocrine disorder, specifically excess growth hormone (GH) secretion, usually due to a pituitary adenoma. This leads to abnormal growth of bones and soft tissues, particularly in adults. Other options explained: B. Albright’s syndrome (McCune-Albright Syndrome): A genetic disorder caused by post-zygotic mutations in the GNAS gene, leading to fibrous dysplasia, café-au-lait spots, and endocrine abnormalities. It is not primarily an endocrine disorder but has endocrine manifestations. C. Paget’s disease: A bone remodeling disorder of unclear etiology, possibly involving genetic and environmental factors, not primarily endocrine. D. Fibrous dysplasia: A developmental bone disorder caused by activating mutations in the GNAS gene, not related to endocrine dysfunction as a primar...

 # The view which best demonstrates inflammation and temporomandibular joint effusion are: A. T2 weighted MR images B. T1 weighted MR images C. Lateral tomogram D. Panoramic radiograph The correct answer is: B. Unilateral and bilateral crossbite Explanation: After cleft palate repair, patients often experience unilateral or bilateral crossbite due to maxillary growth deficiencies. Surgical intervention and scarring can inhibit the forward and lateral growth of the maxilla, leading to discrepancies between the maxillary and mandibular arches. This results in crossbites, which are common in individuals with repaired cleft palate. Other options explained: A. Normal occlusion : Rarely achieved without orthodontic intervention due to maxillary growth issues. C. Anterior open bite : Not a typical finding unless associated with other conditions or habits. D. Anterior deep bite : Uncommon in cleft palate cases as the maxillary hypoplasia usually prevents such occlusion.

 # DiGeorge syndrome is due to: A. Congenital thymic aplasia B. Deficiency of complement factors C. Inborn error of metabolism D. Chromosomal anomaly The correct answer is D. Chromosomal anomaly. The correct answer is: D. Chromosomal anomaly Explanation: DiGeorge syndrome is caused by a chromosomal anomaly, specifically a 22q11.2 deletion.  This deletion leads to developmental defects in the pharyngeal pouches, resulting in: Congenital thymic aplasia or hypoplasia (leading to T-cell deficiency). Parathyroid hypoplasia (causing hypocalcemia). Cardiac defects (e.g., Tetralogy of Fallot, interrupted aortic arch). Facial dysmorphisms. Other options explained: A. Congenital thymic aplasia: While thymic aplasia is a feature of DiGeorge syndrome, it is secondary to the chromosomal deletion. B. Deficiency of complement factors: Seen in complement pathway defects, not in DiGeorge syndrome. C. Inborn error of metabolism: DiGeorge syndrome is not related to metabolic enzyme deficiencies...

 # A 19 year old young girl with previous history of repeated pain over medial canthus and chronic use of nasal decongestants, presented with abrupt onset of fever with chills and rigor, diplopia on lateral gaze, moderate proptosis and chemosis. On examination, the optic disc is congested. Most likely diagnosis is: A. Cavernous sinus thrombosis B. Orbital cellulitis C. Acute ethmoid sinusitis D. Orbital apex syndrome The correct answer is: A. Cavernous sinus thrombosis Explanation: The clinical presentation described—abrupt onset of fever with chills, diplopia , proptosis , chemosis , and optic disc congestion —is characteristic of cavernous sinus thrombosis (CST) . This condition is often secondary to infections in the medial canthus (commonly from facial infections or sinusitis), which can spread to the cavernous sinus via valveless facial veins. Key Differentiation: B. Orbital cellulitis : Also presents with proptosis and chemosis but typically lacks systemic signs like severe f...

 # A 48 years old male reported to you with fractured central incisor with fracture line extending 4 mm gingival below CEJ with thin bone CEJ with thin bone buccally and thick apicopalatally, treatment of choice is:  A. Socket shield technique B. Post and core C. Extraction and implant D. Socket preservation The correct answer is: Socket shield technique Explanation: The socket shield technique is the preferred treatment in this scenario because it preserves the  buccal bone by retaining a thin section of the root (the "shield") after extraction. This technique is ideal for  cases where the buccal bone is thin, as it minimizes bone resorption and supports the soft tissue contour, especially in the aesthetic zone. Other options explained: B. Post and core: Suitable for coronal fractures but not when the fracture extends significantly below the CEJ. C. Extraction and implant: A viable option but may lead to buccal bone loss in cases with thin buccal bone. D. Socket pr...

 # A patient has hypoplasia, microdontia, hypodontia, multiple unerupted teeth, numbness in oral cavity, peripheral paresthesia. This is most likely due to: A. Hyperparathyroidism B. Hypoparathyroidism C. Hyperthyroidism D. Hypothyroidism The correct answer is: B. Hypoparathyroidism Explanation: Hypoparathyroidism can cause a range of dental and neurological symptoms, including: Dental manifestations : Hypoplasia, microdontia, hypodontia, delayed eruption, and multiple unerupted teeth are associated with impaired calcium metabolism. Neurological symptoms : Numbness in the oral cavity and peripheral paresthesia occur due to hypocalcemia, which leads to increased neuromuscular excitability. Other options explained: A. Hyperparathyroidism : May cause brown tumors, loss of lamina dura, and tooth mobility due to increased bone resorption, but not hypoplasia or unerupted teeth. C. Hyperthyroidism : Can lead to accelerated dental development but does not cause hypoplasia or hypodontia. D....

 # The most well recognized technique for orthodontic bonding to porcelain surfaces is: A. Traditional acid-etch technique with phosphoric acid. B. Chemical retention using 4-META coupling agent. C. Chemical and micro-mechanical retention using hydrofluoric acid and a silane coupling agent. D. Chemical retention using hydrofluoric acid only. The correct answer is C.  Chemical and micro-mechanical retention using hydrofluoric acid and a silane coupling agent Explanation: The most effective and well-recognized technique for bonding to porcelain involves etching the porcelain surface with hydrofluoric acid to create micro-mechanical retention, followed by the application of a silane coupling agent to enhance chemical adhesion. This combination ensures a strong bond between the orthodontic bracket and the porcelain surface. A : Phosphoric acid etching is effective for enamel but not adequate for porcelain bonding. B : 4-META is less commonly used for porcelain. D : Hydrofluoric ...