Oral Medicine & Radiology — 30-Min Notes

1. Oral Diagnosis

• Chief complaint: Recorded in patient’s own words; helps identify primary concern and guides diagnosis.

• Provisional diagnosis: Initial diagnosis based on history and clinical findings before investigations.

• Differential diagnosis: List of possible conditions with similar clinical features.

• Tip: NEET often asks sequence → history → examination → investigations → final diagnosis.

2. Pain & Neural Disorders

• Trigeminal Neuralgia: Sudden, sharp, unilateral facial pain along trigeminal nerve distribution. Triggered by light touch.

• Glossopharyngeal Neuralgia: Severe pain in throat, tonsillar area, or ear; aggravated by swallowing.

• Burning Mouth Syndrome: Chronic burning sensation without clinical findings; commonly seen in post-menopausal women.

• Tip: Trigeminal neuralgia → electric shock-like pain.

3. TMJ Disorders

• TMJ Clicking: Indicates disc displacement with reduction.

• TMJ Crepitus: Rough grating sound suggestive of degenerative joint disease (osteoarthritis).

• Trismus: Reduced mouth opening due to muscle spasm, infection, or trauma.

• Tip: Clicking = early TMJ disorder; crepitus = advanced disease.

4. Oral Manifestations of Systemic Diseases

• Diabetes Mellitus: Periodontitis, xerostomia, delayed healing, candidiasis.

• Anemia: Pale oral mucosa, angular cheilitis, atrophic glossitis.

• Hypertension drugs (CCBs): Gingival enlargement.

• Tip: Gingival hyperplasia → phenytoin, cyclosporine, nifedipine.

5. Salivary Gland Disorders

• Xerostomia: Reduced salivary flow causing caries, candidiasis, difficulty in swallowing.

• Sjögren’s Syndrome: Autoimmune disorder affecting salivary and lacrimal glands → dry mouth and dry eyes.

• Sialolithiasis: Salivary stone commonly affecting submandibular gland.

• Tip: Submandibular gland → most common site for stones.

6. Radiographic Basics

• Intraoral Periapical Radiograph (IOPA): Shows entire tooth and surrounding bone; used for periapical lesions.

• Bitewing Radiograph: Best for detecting interproximal caries and crestal bone levels.

• Occlusal Radiograph: Used to detect impacted teeth, stones, and fractures.

• Tip: Bitewing = caries + bone loss.

7. Extraoral Radiography

• OPG (Panoramic Radiograph): Shows entire maxilla, mandible, TMJ, and sinuses.

• Cephalogram: Used in orthodontic diagnosis and growth assessment.

• Submentovertex View: Used for zygomatic arch fractures.

• Tip: OPG → fractures, impacted teeth, cysts.

8. Advanced Imaging

• CBCT: Provides 3D imaging with lower radiation than CT. Used in implant planning and impacted teeth.

• CT Scan: Best for hard tissue evaluation like fractures and tumors.

• MRI: Best for soft tissue lesions and TMJ disc evaluation.

• Tip: MRI → disc, CBCT → bone.

9. Radiographic Appearance of Lesions

• Periapical Granuloma: Well-defined radiolucency at apex of non-vital tooth.

• Radicular Cyst: Larger, corticated periapical radiolucency.

• Ameloblastoma: Multilocular “soap-bubble” radiolucency.

• Tip: Multilocular radiolucency → think ameloblastoma or OKC.

10. High-Yield Repeated Points (NEET MDS)

• Trigeminal neuralgia → sharp, electric shock pain

• TMJ clicking → disc displacement with reduction

• Diabetes → periodontal disease + xerostomia

• Bitewing → interproximal caries detection

• OPG → fractures, impacted teeth

• CBCT → implant planning

• MRI → TMJ disc evaluation