What are the six axes of the Lang & Tonetti risk assessment?

1) BOP%, 2) number of residual pockets ≥5 mm, 3) teeth lost/32, 4) bone loss/age ratio, 5) systemic/genetic conditions, 6) environmental factors (smoking).

What BOP% indicates active disease?

BOP ≤10% = low risk; 10–25% = moderate; >25% = high risk for disease progression.

How does smoking affect periodontal risk?

Non-smoker = low; ex-smoker = moderate; current smoker <10 cigs/day = moderate; ≥10 cigs/day = high risk.

Periodontal Risk Calculator — Lang & Tonetti

Constant	Symbol	Value	Units
Speed of light	c	2.99792458×10⁸	m/s
Planck's constant	h	6.62607015×10⁻³‴	J·s
Boltzmann constant	kʙ	1.380649×10⁻²³	J/K
Avogadro's number	Nₐ	6.02214076×10²³	mol⁻¹
Gravitational constant	G	6.6743×10⁻¹¹	N·m²/kg²
Gas constant	R	8.31446	J/(mol·K)
Elementary charge	e	1.602176634×10⁻¹⁹	C
Electron mass	mₑ	9.1093837015×10⁻³¹	kg
Proton mass	mₚ	1.67262192369×10⁻²⁷	kg
Fine-structure constant	α	7.2973525693×10⁻³	dimensionless

Formula Definitions

The Periodontal Risk Calculator — Lang & Tonetti works by applying a well-defined formula to the values you enter. Understanding the formula behind the calculation helps you interpret the result and check that your inputs are correct. Below we break down the key components that drive the Periodontal Risk.

The core formula used by this calculator is:

Result = f(patient inputs, clinical reference)

Each variable in the formula has a specific meaning:

patient inputs — Age, weight, height, lab values, vitals, or clinical findings entered into the Periodontal Risk.
clinical reference — Reference range, scoring system, or population standard the result is compared against.
Result — Computed clinical score, risk estimate, or diagnostic value.

Note: Clinical results are decision-support only and must be interpreted by a qualified clinician.

How to Use This Calculator

Enter patient clinical data. Enter the patient's age, weight, lab values, vitals, or clinical findings into the Periodontal Risk Calculator — Lang & Tonetti input fields.
Select the clinical scoring system. Select or confirm the appropriate clinical scoring system or reference range for the patient population.
Calculate the clinical score. Press Calculate to compute the clinical score, risk estimate, or diagnostic result.
Interpret the result. Review the output against the provided reference ranges, risk categories, or guideline thresholds. Consult a qualified clinician before acting on results.

Glossary and Definitions

Clinical score: A numeric value derived from patient inputs that estimates risk, severity, or diagnostic likelihood for a given condition.
Reference range: The set of values considered normal for a healthy population, used to interpret a calculated result.
Sensitivity: The probability that a positive result correctly identifies a patient with the condition.
Specificity: The probability that a negative result correctly identifies a patient without the condition.
Periodontal risk calculator: A key concept referenced by the Periodontal Risk: Calculate periodontal disease risk using the Lang & Tonetti hexagonal diagram. Integrates BOP, probing depths, tooth loss, bone loss, systemic factors, and smoking.
Lang Tonetti: A key concept referenced by the Periodontal Risk: Calculate periodontal disease risk using the Lang & Tonetti hexagonal diagram. Integrates BOP, probing depths, tooth loss, bone loss, systemic factors, and smoking.
Gum disease risk: A key concept referenced by the Periodontal Risk: Calculate periodontal disease risk using the Lang & Tonetti hexagonal diagram. Integrates BOP, probing depths, tooth loss, bone loss, systemic factors, and smoking.
Periodontal assessment: A key concept referenced by the Periodontal Risk: Calculate periodontal disease risk using the Lang & Tonetti hexagonal diagram. Integrates BOP, probing depths, tooth loss, bone loss, systemic factors, and smoking.

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