Diseases of the Oral Cavity and Salivary Glands Practice Questions

Q: Which of the following is false regarding pleomorphic adenoma?

Commonly turns malignant. **Explanation:** Pleomorphic Adenoma (Benign Mixed Tumor) is the most common salivary gland tumor, typically involving the superficial lobe of the parotid gland. **Why Option C is False (The Correct Answer):** While Pleomorphic Adenoma has a risk of malignant transformation into **Carcinoma ex Pleomorphic Adenoma**, this occurs in only about **2–10%** of cases (usually in long-standing tumors of 10–15 years). Therefore, saying it "commonly" turns malignant is clinically incorrect. It is primarily a benign tumor. **Analysis of Other Options:** * **Option A (Large in size):** If left untreated, these tumors can grow to a massive size because they are painless and slow-growing, often leading patients to delay seeking medical advice. * **Option B (Encapsulated):** It is a well-demarcated, encapsulated tumor. However, it is known for having a **"false capsule"** with finger-like projections (pseudopods). This is why simple enucleation leads to high recurrence; a superficial parotidectomy is preferred. * **Option D (Slow growing):** A hallmark of Pleomorphic Adenoma is its slow, indolent growth over several years. Sudden rapid increase in size is a red flag for malignant transformation. **High-Yield Clinical Pearls for NEET-PG:** * **Most common site:** Parotid gland (Tail of the parotid). * **Histology:** Shows both epithelial and mesenchymal elements (hence "Mixed Tumor"). Look for a **chondromyxoid stroma**. * **Treatment of choice:** Superficial parotidectomy (to avoid the facial nerve and prevent recurrence from pseudopods). * **Nerve involvement:** Facial nerve palsy is rare in Pleomorphic Adenoma; if present, suspect malignancy.

Q: Which of the following is NOT a treatment option for chronic submucosal fibrosis?

Excision. **Explanation:** Oral Submucous Fibrosis (OSMF) is a chronic, progressive, premalignant condition characterized by juxta-epithelial inflammatory reactions followed by fibroelastic changes in the lamina propria. **Why Excision is NOT a treatment option:** OSMF is a **generalized field disease** affecting the entire oral mucosa. Surgical excision of the fibrotic bands is generally avoided because the resulting raw area heals by secondary intention or scarring, which often leads to **rebound fibrosis** and further worsening of trismus (lockjaw). Surgery is reserved only for extreme cases where it is combined with skin or mucosal grafting (e.g., radial forearm flap), but simple excision alone is not a standard treatment modality. **Analysis of other options:** * **Intralesional Steroids (A):** These are the mainstay of medical management. They act by inhibiting the inflammatory response and decreasing fibroblast proliferation. * **Antioxidants (B):** Lycopene, Vitamin A, C, and E are used to scavenge free radicals and arrest the progression of the disease. * **Hyaluronidase (D):** This enzyme breaks down hyaluronic acid, decreasing the viscosity of the intercellular matrix and helping to soften the fibrous bands. It is often used in combination with steroids. **Clinical Pearls for NEET-PG:** * **Etiology:** Strongly associated with **Areca nut (Betel nut)** chewing. * **Pathogenesis:** Alkaloids (Arecoline) stimulate fibroblasts to produce excess collagen, while Flavonoids inhibit Collagenase. * **Clinical Feature:** Characterized by "burning sensation" on eating spicy food and "vertical blanched bands" in the buccal mucosa. * **Malignant Transformation:** OSMF has a high malignant transformation rate (approx. 7–13%), most commonly leading to **Squamous Cell Carcinoma**.

Q: A 45-year-old male presented for a routine dental checkup. All teeth in the lower right quadrant were vital. A panoramic radiograph was taken. Which of the following can be the most probable diagnosis?

Stafne bone cyst. ***Stafne bone cyst*** - **Stafne bone cyst** is an **asymptomatic radiolucent lesion** typically found **below the inferior alveolar canal** in the **posterior mandible** of middle-aged males during routine radiographic examination. - The **vital teeth** in the affected quadrant strongly support this diagnosis, as Stafne cysts are **developmental defects** containing **salivary gland tissue** and do not affect tooth vitality. *Dentigerous cyst* - **Dentigerous cysts** are associated with the **crown of an unerupted tooth**, typically **third molars** or **canines**. - They present as **unilocular radiolucencies** surrounding the **crown** of an impacted tooth, which is not described in this case. *Radicular cyst* - **Radicular cysts** arise from **chronic periapical inflammation** and are associated with **non-vital teeth** with **pulpal necrosis**. - Since all teeth in the lower right quadrant are **vital**, this diagnosis is ruled out as radicular cysts require **endodontic infection**. *Calcifying odontogenic cyst* - **Calcifying odontogenic cyst** (Gorlin cyst) typically presents as a **mixed radiolucent-radiopaque lesion** with **calcifications**. - It commonly occurs in the **anterior maxilla** and shows **calcific deposits** on radiographs, unlike the presumed **radiolucent lesion** in the posterior mandible.

Q: Stones in the distal portion of Wharton's duct are best visualized by which radiographic view?

Standard mandibular occlusal view. **Explanation:** **1. Why the Standard Mandibular Occlusal View is Correct:** Wharton’s duct (the submandibular duct) runs along the floor of the mouth. Stones (sialoliths) in the **distal portion** of this duct are positioned horizontally above the mylohyoid muscle. The **Standard Mandibular Occlusal View** is the gold standard for visualizing these stones because the X-ray beam is directed perpendicular to the floor of the mouth. This prevents the radiopaque stone from being "masked" or superimposed by the dense cortical bone of the mandible, providing a clear view of the soft tissues in the floor of the mouth. **2. Why the Other Options are Incorrect:** * **Lateral Oblique View of the Mandible:** This is better suited for visualizing stones in the **proximal portion** (near the hilum) of the submandibular gland or stones within the gland parenchyma itself. * **Panoramic Film (OPG):** While useful for a general survey, OPG often results in the superimposition of the hyoid bone or the mandibular body over the floor of the mouth, making small distal stones difficult to identify. * **Intraoral Periapical Radiograph (IOPA):** The film size is too small and the angle is designed to visualize teeth and periapical structures, not the soft tissues of the floor of the mouth. **3. Clinical Pearls for NEET-PG:** * **80% Rule:** 80% of all salivary stones occur in the **Submandibular gland** (due to alkaline pH, high calcium/mucin content, and the upward, tortuous course of Wharton’s duct). * **Radiopacity:** 80% of submandibular stones are radiopaque (visible on X-ray), whereas 80% of parotid stones are radiolucent. * **Bimanual Palpation:** Distal Wharton’s duct stones can often be felt manually in the floor of the mouth. * **Sialography:** This is contraindicated during acute infection.

Q: What is the condition involved with an unerupted or impacted tooth?

All of the above. The correct answer is **D. All of the above.** ### **Explanation and Medical Concept** The common denominator in these three conditions is their **odontogenic origin**, specifically their association with the **dental follicle** of an unerupted or impacted tooth (most commonly the mandibular third molar or maxillary canine). 1. **Dentigerous Cyst (Follicular Cyst):** This is the most common developmental odontogenic cyst. It originates from the separation of the follicle from around the crown of an **unerupted tooth**. Radiographically, it appears as a well-defined unilocular lucency attached to the cemento-enamel junction (CEJ). 2. **Mural Ameloblastoma:** This is a variant of Unicystic Ameloblastoma (Type 3). In many cases, these tumors arise from the epithelial lining of a pre-existing dentigerous cyst. Therefore, they are frequently found in association with an **impacted tooth**. 3. **Adenomatoid Odontogenic Tumor (AOT):** Often called the "Two-Thirds Tumor," it occurs in the maxilla (2/3 cases), in young females (2/3 cases), and is associated with an **impacted tooth** (2/3 cases, usually the maxillary canine). ### **Clinical Pearls for NEET-PG** * **Dentigerous Cyst:** If the follicular space around an unerupted tooth is **>3mm**, suspect a dentigerous cyst. * **AOT (Adenomatoid Odontogenic Tumor):** Look for "snowflake" calcifications within the radiolucency on X-ray. It typically involves the crown and part of the root, unlike a dentigerous cyst which stops at the CEJ. * **Ameloblastoma:** While the multicystic type shows a "soap bubble" or "honeycomb" appearance, the **Unicystic** type (associated with impacted teeth) mimics a cyst and has a better prognosis. * **Pindborg Tumor (CEOT):** Another differential for impacted teeth, characterized by "driven snow" calcifications.

Q: What is the investigation of choice for parotid gland calculi?

Sialography. **Explanation:** The investigation of choice for parotid gland calculi (sialolithiasis) is **Sialography**. This involves the injection of a radio-opaque contrast medium into the salivary duct followed by radiographic imaging. **Why Sialography is the Correct Answer:** Unlike the submandibular gland, where 80% of stones are radio-opaque, approximately **60-80% of parotid stones are radiolucent** (composed mainly of organic matter). Sialography is the gold standard because it identifies these radiolucent stones as "filling defects" within the ductal system. It also provides superior detail regarding ductal anatomy, helping to identify strictures or diverticula associated with chronic sialadenitis. **Analysis of Incorrect Options:** * **A. X-ray:** Most parotid stones are radiolucent and will not be visible on a plain radiograph (e.g., AP view or intraoral films). * **B. Ultrasound (USG):** While often the first-line screening tool due to its non-invasive nature, it is operator-dependent and may miss small stones (<2mm) or those located deep in the parotid tail. * **D. CT Scan:** Highly sensitive for calcified stones, but less effective than sialography for visualizing the internal ductal architecture and radiolucent obstructions. **NEET-PG High-Yield Pearls:** * **Submandibular vs. Parotid:** Submandibular stones are more common (80%) and usually radio-opaque. Parotid stones are less common (20%) and usually radiolucent. * **Contraindication:** Sialography should **never** be performed during an acute infection (sialadenitis) as it can worsen the condition or spread the infection. * **Modern Gold Standard:** While Sialography is the traditional "investigation of choice" in exams, **MR Sialography** (non-invasive) and **Diagnostic Sialendoscopy** are increasingly preferred in modern clinical practice.

Q: Which of the following is NOT typically a white lesion found in the oral cavity?

Erythroplakia. **Explanation:** The correct answer is **D. Erythroplakia**. **1. Why Erythroplakia is the correct answer:** As the name implies (*Erythro* = red, *plakia* = patch), Erythroplakia presents as a fiery red, velvety patch on the oral mucosa that cannot be characterized clinically or pathologically as any other condition. Unlike white lesions, which often involve hyperkeratosis (thickening of the keratin layer), Erythroplakia is characterized by epithelial atrophy and increased vascularity. It is clinically significant because it has a much higher transformation rate into **Squamous Cell Carcinoma (SCC)** compared to Leukoplakia (white patches). **2. Why the other options are incorrect:** * **Spongy Nevus (White Sponge Nevus):** A rare genetic condition (autosomal dominant) causing thick, bilateral, white, "spongy" plaques, usually on the buccal mucosa. * **Lichen Planus:** An inflammatory condition that typically presents as **Wickham’s striae** (white, lace-like patterns) on the buccal mucosa. * **Candidiasis (Oral Thrush):** A fungal infection caused by *Candida albicans* that presents as "curdy white" patches. A key diagnostic feature is that these patches **can be scraped off**, leaving an erythematous (red) base. **NEET-PG High-Yield Pearls:** * **Pre-malignant potential:** Erythroplakia > Speckled Leukoplakia > Proliferative Verrucous Leukoplakia > Homogenous Leukoplakia. * **Biopsy Rule:** Any red or white lesion persisting for more than 2 weeks after removing local irritants must be biopsied to rule out malignancy. * **Fordyce Spots:** These are ectopic sebaceous glands (yellowish-white spots) and are considered a normal anatomical variant, not a disease.

Q: Which of the following is NOT a precancerous lesion of the oral cavity?

Diffuse aphthous ulcers. **Explanation:** The correct answer is **Diffuse aphthous ulcers**. **1. Why it is the correct answer:** Aphthous ulcers (canker sores) are common, painful, inflammatory lesions of the oral mucosa. They are **not** precancerous. Their etiology is typically related to immune dysregulation, stress, nutritional deficiencies (B12, Iron, Folate), or trauma. They heal without leaving a permanent change in the cellular architecture and do not carry a risk of malignant transformation into squamous cell carcinoma. **2. Analysis of incorrect options (Precancerous Lesions):** * **Leukoplakia:** Defined by the WHO as a "white patch or plaque that cannot be characterized clinically or pathologically as any other disease." It is the most common precancerous lesion, with a malignant transformation rate of approximately 3–5%. * **Erythroplakia:** This refers to a fiery red patch that cannot be attributed to any other cause. It is the **most dangerous** precancerous lesion, with a malignant transformation rate as high as 50–90%. * **Oral Submucous Fibrosis (OSMF):** A chronic, progressive condition characterized by juxta-epithelial fibrosis. It is strongly associated with **areca nut (betel nut)** chewing. It is considered a precancerous condition with a transformation rate of about 7–13%. **3. High-Yield Clinical Pearls for NEET-PG:** * **Precancerous Lesion:** A morphologically altered tissue in which cancer is more likely to occur than its normal counterpart (e.g., Leukoplakia, Erythroplakia). * **Precancerous Condition:** A generalized state associated with a significantly increased risk of cancer (e.g., OSMF, Lichen Planus, Xeroderma pigmentosum, Plummer-Vinson Syndrome). * **Speckled Leukoplakia:** Also known as Erythroleukoplakia; it carries a higher risk of malignancy than homogenous leukoplakia. * **Most common site for Oral Cancer:** Lateral border of the tongue.

Q: Conley's Pointer is used to identify which of the following nerves?

The Facial Nerve. **Explanation:** **Conley’s Pointer** (also known as the **Tragal Pointer**) is a critical anatomical landmark used during parotid surgery to identify the **Facial Nerve (CN VII)**. The pointer is the deep, triangular extension of the auricular cartilage of the meatus. The main trunk of the facial nerve is typically located approximately **1.0 to 1.5 cm deep and slightly anterior-inferior** to the tip of this pointer. Identifying the nerve at this exit point from the stylomastoid foramen is the safest way to begin a superficial parotidectomy to avoid accidental nerve injury. **Analysis of Options:** * **The Lingual Nerve (Option A):** This nerve is found in the submandibular region and floor of the mouth. It is identified during submandibular gland excision, not via the tragal pointer. * **The Hypoglossal Nerve (Option B):** This nerve is located deep to the posterior belly of the digastric muscle in the carotid triangle. While it is a landmark in neck dissections, Conley’s pointer is not used for its localization. * **The Facial Nerve (Option C):** Correct. Conley's pointer is one of the five standard landmarks for the facial nerve trunk. **High-Yield Clinical Pearls for NEET-PG:** Other essential landmarks to identify the Facial Nerve trunk include: 1. **Tympanomastoid Suture Line:** The nerve is located 6–8 mm deep to this suture. 2. **Posterior Belly of Digastric Muscle:** The nerve lies just superior to where the muscle attaches to the mastoid notch. 3. **Styloid Process:** The nerve is usually found lateral to the styloid process. 4. **Luschka’s Nerve:** A small branch of the post-auricular artery that bleeds near the nerve trunk (the "bell-ringer’s artery").

Q: Multiple dentigerous cysts are present in which of the following conditions?

Both of the above. **Explanation:** A **dentigerous cyst** (follicular cyst) is an odontogenic cyst that develops around the crown of an unerupted or developing tooth. While solitary dentigerous cysts are common, the presence of **multiple dentigerous cysts** is rare and typically associated with specific systemic syndromes. 1. **Maroteaux-Lamy Syndrome (Mucopolysaccharidosis Type VI):** This is a lysosomal storage disorder caused by a deficiency of the enzyme arylsulfatase B. It is characterized by skeletal abnormalities and coarse facial features. In the oral cavity, it frequently presents with multiple enlarged dental follicles and dentigerous cysts, often associated with impacted teeth. 2. **Cleidocranial Dysplasia:** This is an autosomal dominant skeletal disorder (RUNX2 gene mutation) characterized by hypoplastic/absent clavicles and delayed closure of cranial sutures. A hallmark dental finding is the presence of **multiple supernumerary teeth** and failure of permanent teeth to erupt. These impacted teeth frequently lead to the formation of multiple dentigerous cysts. **Why the other options are incorrect:** Since both Maroteaux-Lamy syndrome and Cleidocranial dysplasia are well-documented causes of multiple dentigerous cysts, "Both of the above" is the most accurate choice. **High-Yield Clinical Pearls for NEET-PG:** * **Radiological Appearance:** A dentigerous cyst appears as a well-defined unilocular radiolucency attached to the neck of an unerupted tooth (cementoenamel junction). * **Differential Diagnosis for Multiple Odontogenic Keratocysts (OKCs):** Do not confuse multiple dentigerous cysts with multiple OKCs. Multiple OKCs are a classic feature of **Gorlin-Goltz Syndrome** (Nevoid Basal Cell Carcinoma Syndrome). * **Other associations:** Multiple dentigerous cysts can also rarely be seen in Gardner Syndrome.

Question 1

Which of the following is false regarding pleomorphic adenoma?

Accepted Answer

Commonly turns malignant

Answer

Large in size

Answer

Encapsulated

Answer

Slow growing

Question 2

Which of the following is NOT a treatment option for chronic submucosal fibrosis?

Accepted Answer

Excision

Answer

Intralesional steroids

Answer

Antioxidants

Answer

Hyaluronidase

Question 3

A 45-year-old male presented for a routine dental checkup. All teeth in the lower right quadrant were vital. A panoramic radiograph was taken. Which of the following can be the most probable diagnosis?

Accepted Answer

Stafne bone cyst

Answer

Dentigerous cyst

Answer

Radicular cyst

Answer

Calcifying odontogenic cyst

Question 4

Stones in the distal portion of Wharton's duct are best visualized by which radiographic view?

Accepted Answer

Standard mandibular occlusal view

Answer

Lateral oblique view of the mandible

Answer

Panoramic film

Answer

Intraoral periapical radiograph (IOPA)

Question 5

What is the condition involved with an unerupted or impacted tooth?

Accepted Answer

All of the above

Answer

Dentigerous cyst

Answer

Mural ameloblastoma

Answer

Adenomatoid odontogenic tumor

Question 6

What is the investigation of choice for parotid gland calculi?

Accepted Answer

Sialography

Answer

X-ray

Answer

Ultrasound (USG)

Answer

CT scan

Question 7

Which of the following is NOT typically a white lesion found in the oral cavity?

Accepted Answer

Erythroplakia

Answer

Spongy nevus

Answer

Lichen planus

Answer

Candidiasis

Question 8

Which of the following is NOT a precancerous lesion of the oral cavity?

Accepted Answer

Diffuse aphthous ulcers

Answer

Leukoplakia

Answer

Erythroplakia

Answer

Diffuse oral submucous fibrosis

Question 9

Conley's Pointer is used to identify which of the following nerves?

Accepted Answer

The Facial Nerve

Answer

The Lingual Nerve

Answer

The Hypoglossal Nerve

Answer

All the above

Question 10

Multiple dentigerous cysts are present in which of the following conditions?

Accepted Answer

Both of the above

Answer

Maroteux Lamy syndrome

Answer

Cleidocranial dysplasia

Answer

None of the above

Diseases of the Oral Cavity and Salivary Glands — MCQs

Diseases of the Oral Cavity and Salivary Glands — MCQs

On this page

Practice by Chapter

Want unlimited practice?