← All NEET MDS Topics

Water Fluoridation & Fluoride Toxicity

Public Health Dentistry • NEET MDS Study Guide • AI-Generated Notes

⭐ High-Yield Facts for Exam

  • Optimal water fluoride ≈ 0.7 ppm.
  • CLD ≈ 32-64 mg/kg.
  • STD = CLD/4.
  • Chronic excess = dental/skeletal fluorosis.
  • Dean's index assesses fluorosis.

Water Fluoridation & Toxicity

Optimal Level

≈ 0.7 ppm (current); historically 0.7-1.2 ppm by climate. Reduces caries via systemic + topical effect.

Toxicity

  • Certainly Lethal Dose (CLD) ≈ 32-64 mg F/kg.
  • Safely Tolerated Dose (STD) ≈ CLD/4 (~8-16 mg/kg).
  • Chronic excess → dental fluorosis (mottled enamel) and, at high levels, skeletal fluorosis.

Assessment

Dean's fluorosis index grades enamel changes from questionable to severe.

Exam Tips ⭐

Optimal ≈ 0.7 ppm; CLD ≈ 32-64 mg/kg; STD = CLD/4; chronic excess = fluorosis (Dean's index).

📝 Practice MCQs — Water Fluoridation & Fluoride Toxicity

Q1. The certainly lethal dose of fluoride is approximately:
A. 5-10 mg/kg
B. 32-64 mg/kg
C. 100-200 mg/kg
D. 1 mg/kg
Show Answer
✅ Answer: B
CLD is about 32-64 mg F/kg body weight.
Q2. Chronic excess fluoride during enamel formation causes:
A. Caries
B. Dental fluorosis
C. Erosion
D. Abrasion
Show Answer
✅ Answer: B
Chronic excess causes dental (and possibly skeletal) fluorosis.
Q3. Safely tolerated dose (STD) of fluoride equals:
A. CLD x 2
B. CLD/4
C. CLD/10
D. Equal to CLD
Show Answer
✅ Answer: B
STD is taken as one-fourth of the CLD.
📧 Get Free NEET MDS MCQs in Your Inbox
50 high-yield MCQs + mnemonics + AI study tips — completely free
No spam. Unsubscribe anytime.

Related Topics

Dental Indices — DMFT, OHI-S, CPIFluoride & Preventive MeasuresNational Health Programs (India)