NEET-PG 2015 — Dental

Q: What is the recommended treatment for oral sores caused by inhaled steroids?

Miconazole. ***Miconazole*** - **Miconazole** is an **antifungal medication** available in gel or oral tablet forms, effective in treating oral thrush (candidiasis), a common side effect of inhaled steroid use. - Its **broad-spectrum antifungal activity** means it targets the *Candida* species responsible for these oral sores, relieving symptoms and promoting healing. *Clotrimazole* - While **clotrimazole** is an **antifungal medication** that can be used for oral candidiasis, it is typically available as troches (lozenges) and may be less commonly prescribed for this specific condition than miconazole in some regions. - Its mechanism of action involves **inhibiting ergosterol synthesis**, disrupting the fungal cell membrane; however, **miconazole** is often favored for its ease of application and efficacy in oral candidiasis. *Fusidic acid* - **Fusidic acid** is an **antibiotic** primarily used to treat bacterial infections, particularly those caused by *Staphylococcus* species. - It has **no antifungal properties**, making it ineffective against oral sores caused by inhaled steroid-induced candidiasis. *Mupirocin ointment* - **Mupirocin** is an **antibiotic ointment** used topically to treat bacterial skin infections, such as impetigo. - It works by **inhibiting bacterial protein synthesis** and is not effective against fungal infections like oral thrush. [Practice more Dental PYQs on OnCourse]

Q: Epulis arises from -

Gingiva. ***Gingiva*** - **Epulis** refers to a localized, tumor-like enlargement of the **gingiva** (gum tissue). - These lesions are typically inflammatory or reactive in nature, arising from the connective tissue of the gum. *Enamel* - **Enamel** is the hard, outermost protective layer of the tooth crown, which is of ectodermal origin. - Lesions originating from enamel itself are rare and typically involve developmental defects or structural damage, not soft tissue growths like epulis. *Root of teeth* - The **root of the teeth** is embedded in the alveolar bone and covered by cementum, with the surrounding structures including the periodontal ligament and alveolar bone. - While infections or cysts can arise from the root, epulis specifically describes a growth of the overlying **gingival tissue**. *Pulp* - The **pulp** is the soft tissue inside the tooth containing nerves, blood vessels, and connective tissue. - Pathologies originating from the pulp are typically infectious (pulpitis), degenerative, or involve growth of odontogenic tissues (e.g., pulp polyps within the tooth chamber), not surface gingival lesions. [Practice more Dental PYQs on OnCourse]

Q: Which subtype of Acute Myeloid Leukemia (AML) is most commonly associated with gum hypertrophy?

Acute Myeloid Leukemia M4. ***M4*** - **Acute Myeloid Leukemia (AML) M4** is associated with **monocytic differentiation**, leading to gum hypertrophy due to infiltration of the gums by leukemic cells [1]. - Patients may present with **gingival bleeding**, pain, and swelling in addition to other systemic symptoms of leukemia. *M3* - Known as **acute promyelocytic leukemia**, it typically presents with **coagulopathy** and not gum hypertrophy [1]. - Characterized by **promyelocytes** with heavy granulation and the presence of **faggot cells** (auer rods) [1]. *M2* - Represents a **myeloblastic type** of acute leukemia but is less commonly associated with **gingival hyperplasia**. - Associated with **more typical myeloid features** and presents with **anemia** and **thrombocytopenia**. *M1* - This is a **minimally differentiated type** of acute myeloid leukemia with **myeloblasts** and no significant differentiating features like gum hypertrophy. - Often presents with **rapid onset of symptoms** related to bone marrow failure, rather than localized gum issues. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 620-622. [Practice more Dental PYQs on OnCourse]

Q: What is the most common location for an extra permanent tooth to erupt?

Upper incisor. ***Upper incisor*** - The most common supernumerary tooth is the **mesiodens**, which typically erupts in the **maxillary midline** between the central incisors. - This region is frequently affected by developmental anomalies that lead to the formation of an **extra permanent tooth**. *Canine* - While supernumerary canines can occur, they are **significantly less common** than supernumerary incisors or molars. - Their presence often causes **impaction or displacement** of adjacent permanent teeth. *Molar* - Supernumerary molars, particularly **paramolars** (buccal or lingual to molars) and **distomolars** (distal to third molars), are the second most common type of supernumerary teeth. - However, they are still **less frequent** than mesiodens in the incisor region. *Lower incisor* - Supernumerary lower incisors are **rare** compared to those in the upper arch. - When present, they can cause **crowding or malocclusion** in the mandibular anterior region. [Practice more Dental PYQs on OnCourse]

Q: Caldwell Luc Surgery has its approach to the maxillary antrum through ?

Gingivolabial sulcus. ***Gingivolabial sulcus*** - The Caldwell Luc approach involves an incision made in the **gingivolabial sulcus** of the upper jaw to access the anterior wall of the maxillary sinus. - This provides a direct and wide approach to the maxillary antrum for surgical procedures. *Inferior orbital rim* - An incision near the **inferior orbital rim** is generally used for orbital surgeries or approaches to the orbit, not directly for the maxillary antrum. - This approach offers access to the orbital floor and associated structures. *Nasal septum* - The **nasal septum** is a cartilaginous and bony wall separating the nostrils. Surgical approaches involving the septum are typically for septoplasty or access to the sphenoid sinus. - This anatomical location does not provide direct access to the maxillary antrum. *Cribriform plate* - The **cribriform plate** is a part of the ethmoid bone in the skull base and is associated with the sense of smell. - Access to this area is primarily for anterior cranial fossa surgeries and is entirely separate from the maxillary antrum. [Practice more Dental PYQs on OnCourse]

8 Previous Year Questions with Answers & Explanations

Questions

What is the recommended treatment for oral sores caused by inhaled steroids?

Epulis arises from -

Which subtype of Acute Myeloid Leukemia (AML) is most commonly associated with gum hypertrophy?

What is the most common location for an extra permanent tooth to erupt?

Caldwell Luc Surgery has its approach to the maxillary antrum through ?

Which of the following is not a premalignant condition for oral cancer?

Which of the following statements is true regarding dentigerous cysts?

In which of the following causes of oral ulcers are auto-antibodies not seen?

NEET-PG 2015 - Dental NEET-PG Practice Questions and MCQs

Question 1: What is the recommended treatment for oral sores caused by inhaled steroids?

A. Fusidic acid
B. Mupirocin ointment
C. Clotrimazole
D. Miconazole (Correct Answer)

Explanation: ***Miconazole*** - **Miconazole** is an **antifungal medication** available in gel or oral tablet forms, effective in treating oral thrush (candidiasis), a common side effect of inhaled steroid use. - Its **broad-spectrum antifungal activity** means it targets the *Candida* species responsible for these oral sores, relieving symptoms and promoting healing. *Clotrimazole* - While **clotrimazole** is an **antifungal medication** that can be used for oral candidiasis, it is typically available as troches (lozenges) and may be less commonly prescribed for this specific condition than miconazole in some regions. - Its mechanism of action involves **inhibiting ergosterol synthesis**, disrupting the fungal cell membrane; however, **miconazole** is often favored for its ease of application and efficacy in oral candidiasis. *Fusidic acid* - **Fusidic acid** is an **antibiotic** primarily used to treat bacterial infections, particularly those caused by *Staphylococcus* species. - It has **no antifungal properties**, making it ineffective against oral sores caused by inhaled steroid-induced candidiasis. *Mupirocin ointment* - **Mupirocin** is an **antibiotic ointment** used topically to treat bacterial skin infections, such as impetigo. - It works by **inhibiting bacterial protein synthesis** and is not effective against fungal infections like oral thrush.

Question 2: Epulis arises from -

A. Enamel
B. Root of teeth
C. Gingiva (Correct Answer)
D. Pulp

Explanation: ***Gingiva*** - **Epulis** refers to a localized, tumor-like enlargement of the **gingiva** (gum tissue). - These lesions are typically inflammatory or reactive in nature, arising from the connective tissue of the gum. *Enamel* - **Enamel** is the hard, outermost protective layer of the tooth crown, which is of ectodermal origin. - Lesions originating from enamel itself are rare and typically involve developmental defects or structural damage, not soft tissue growths like epulis. *Root of teeth* - The **root of the teeth** is embedded in the alveolar bone and covered by cementum, with the surrounding structures including the periodontal ligament and alveolar bone. - While infections or cysts can arise from the root, epulis specifically describes a growth of the overlying **gingival tissue**. *Pulp* - The **pulp** is the soft tissue inside the tooth containing nerves, blood vessels, and connective tissue. - Pathologies originating from the pulp are typically infectious (pulpitis), degenerative, or involve growth of odontogenic tissues (e.g., pulp polyps within the tooth chamber), not surface gingival lesions.

Question 3: Which subtype of Acute Myeloid Leukemia (AML) is most commonly associated with gum hypertrophy?

A. Acute Myeloid Leukemia M2
B. Acute Myeloid Leukemia M3
C. Acute Myeloid Leukemia M4 (Correct Answer)
D. Acute Myeloid Leukemia M1

Explanation: ***M4*** - **Acute Myeloid Leukemia (AML) M4** is associated with **monocytic differentiation**, leading to gum hypertrophy due to infiltration of the gums by leukemic cells [1]. - Patients may present with **gingival bleeding**, pain, and swelling in addition to other systemic symptoms of leukemia. *M3* - Known as **acute promyelocytic leukemia**, it typically presents with **coagulopathy** and not gum hypertrophy [1]. - Characterized by **promyelocytes** with heavy granulation and the presence of **faggot cells** (auer rods) [1]. *M2* - Represents a **myeloblastic type** of acute leukemia but is less commonly associated with **gingival hyperplasia**. - Associated with **more typical myeloid features** and presents with **anemia** and **thrombocytopenia**. *M1* - This is a **minimally differentiated type** of acute myeloid leukemia with **myeloblasts** and no significant differentiating features like gum hypertrophy. - Often presents with **rapid onset of symptoms** related to bone marrow failure, rather than localized gum issues. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 620-622.

Question 4: What is the most common location for an extra permanent tooth to erupt?

A. Upper incisor (Correct Answer)
B. Canine
C. Molar
D. Lower incisor

Explanation: ***Upper incisor*** - The most common supernumerary tooth is the **mesiodens**, which typically erupts in the **maxillary midline** between the central incisors. - This region is frequently affected by developmental anomalies that lead to the formation of an **extra permanent tooth**. *Canine* - While supernumerary canines can occur, they are **significantly less common** than supernumerary incisors or molars. - Their presence often causes **impaction or displacement** of adjacent permanent teeth. *Molar* - Supernumerary molars, particularly **paramolars** (buccal or lingual to molars) and **distomolars** (distal to third molars), are the second most common type of supernumerary teeth. - However, they are still **less frequent** than mesiodens in the incisor region. *Lower incisor* - Supernumerary lower incisors are **rare** compared to those in the upper arch. - When present, they can cause **crowding or malocclusion** in the mandibular anterior region.

Question 5: Caldwell Luc Surgery has its approach to the maxillary antrum through ?

A. Gingivolabial sulcus (Correct Answer)
B. Inferior orbital rim
C. Nasal septum
D. Cribriform plate

Explanation: ***Gingivolabial sulcus*** - The Caldwell Luc approach involves an incision made in the **gingivolabial sulcus** of the upper jaw to access the anterior wall of the maxillary sinus. - This provides a direct and wide approach to the maxillary antrum for surgical procedures. *Inferior orbital rim* - An incision near the **inferior orbital rim** is generally used for orbital surgeries or approaches to the orbit, not directly for the maxillary antrum. - This approach offers access to the orbital floor and associated structures. *Nasal septum* - The **nasal septum** is a cartilaginous and bony wall separating the nostrils. Surgical approaches involving the septum are typically for septoplasty or access to the sphenoid sinus. - This anatomical location does not provide direct access to the maxillary antrum. *Cribriform plate* - The **cribriform plate** is a part of the ethmoid bone in the skull base and is associated with the sense of smell. - Access to this area is primarily for anterior cranial fossa surgeries and is entirely separate from the maxillary antrum.

Question 6: Which of the following is not a premalignant condition for oral cancer?

A. Leukoplakia
B. Erythroplakia
C. Systemic Sclerosis (Correct Answer)
D. Oral submucous fibrosis

Explanation: ***Systemic Sclerosis*** - Systemic sclerosis is primarily an **autoimmune disease** affecting connective tissue and does not have a direct association with the development of oral cancer. - Although oral manifestations can occur, systemic sclerosis is **not classified** as a premalignant condition for oral malignancies. *Leukoplakia* - Leukoplakia is characterized by **white patches** in the oral cavity and is considered a potentially **premalignant** lesion [1]. - It has a known association with the development of **squamous cell carcinoma** in the oral region [1]. *Erythroplakia* - Erythroplakia presents as **red lesions** in the oral cavity and has a higher risk of **malignant transformation** compared to leukoplakia. - It is regarded as a significant **premalignant condition** for oral cancer. *Oral submucous fibrosis* - This condition involves **fibrosis** of the oral mucosa and is recognized as a **premalignant condition** due to its association with increased cancer risk. - It often develops in individuals with a history of **betel quid** or areca nut use, contributing to cancer risk in the oral cavity [2]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 344-345. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lung, pp. 738-739.

Question 7: Which of the following statements is true regarding dentigerous cysts?

A. It arises in relation to unerupted teeth. (Correct Answer)
B. It commonly encroaches upon the maxillary antrum.
C. The mandibular third molar is a common site for occurrence.
D. Dentigerous cysts are more common in the mandible than in the maxilla.

Explanation: ***It arises in relation to unerupted teeth.*** - A **dentigerous cyst** (also known as a follicular cyst) develops from the **reduced enamel epithelium** covering the crown of an un-erupted or impacted tooth. - It is the most common developmental odontogenic cyst and is always associated with the **crown of an impacted tooth**. *It commonly encroaches upon the maxillary antrum.* - While dentigerous cysts can occur with impacted maxillary teeth (like canines), the statement that they **commonly encroach upon the maxillary antrum** is not universally true or a defining characteristic. This is more often seen with cysts of maxillary molars when they are high in the maxilla. - The most common sites are mandibular third molars and maxillary canines, and encroachment on the antrum is not a primary diagnostic feature across all cases. *The mandibular third molar is a common site for occurrence.* - This statement is **true**; the mandibular third molar is indeed the most common tooth associated with dentigerous cysts. However, the question asks for the **most true** statement which is the definition of a dentigerous cyst. - Other common sites include maxillary canines and mandibular premolars. *Dentigerous cysts are more common in the mandible than in the maxilla.* - While the **mandibular third molar** is the most frequently involved tooth, statistically, dentigerous cysts show a roughly **equal distribution** or a slight predilection for the maxilla when all affected teeth are considered (maxillary canines are also very common), making this statement less accurate than the defining characteristic. - The prevalence between the two jaws can vary depending on the study population, but it's not definitively more common in the mandible overall.

Question 8: In which of the following causes of oral ulcers are auto-antibodies not seen?

A. Behcet disease (Correct Answer)
B. SLE
C. Pemphigus
D. Celiac disease

Explanation: ***Behcet disease*** - Behcet disease is characterized by **recurrent oral and genital ulcers**, along with **eye lesions**, but it does not involve autoantibody formation. - The underlying mechanism is believed to be **immune dysregulation** rather than autoimmunity, making it distinctive. *Celiac disease* - In Celiac disease, **anti-tissue transglutaminase** antibodies are present, which are involved in the body's response to gluten. - Oral ulcers associated with Celiac are often related to nutrient deficiencies, particularly **iron and folate**. *SLE* - Systemic lupus erythematosus (SLE) is marked by various autoantibodies, including **antinuclear antibodies (ANA)** [1]. - Oral ulcers can occur in SLE, and these are a manifestation of its **autoimmune nature** [1]. *Pemphigus* - Pemphigus is characterized by the presence of **autoantibodies** against desmogleins, leading to **blistering** and ulcer formation. - Oral ulcers are common in this condition due to the **disruption of mucosal integrity** caused by the autoimmune response. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, p. 226.