When do primary (baby) teeth erupt?

Lower central incisors: 6–10 months. Upper central incisors: 8–12 months. All 20 primary teeth typically erupt by age 3.

When do permanent teeth erupt?

First permanent molars and incisors: 6–7 years. Most permanent teeth complete by age 12–13, except third molars (17–25 years).

What counts as delayed eruption?

No teeth by 13 months or absence of a permanent tooth 6+ months beyond the average eruption date warrants evaluation.

Tooth Eruption Timeline Calculator

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

Constant

Symbol

Value

Speed of light

2.99792458×10⁸

Planck's constant

6.62607015×10⁻³‴

Boltzmann constant

kʙ

1.380649×10⁻²³

Avogadro's number

Nₐ

6.02214076×10²³

Gravitational constant

6.6743×10⁻¹¹

Gas constant

8.31446

Elementary charge

1.602176634×10⁻¹⁹

Electron mass

mₑ

9.1093837015×10⁻³¹

Proton mass

mₚ

1.67262192369×10⁻²⁷

Fine-structure constant

7.2973525693×10⁻³

Formula Definitions

The Tooth Eruption Timeline Calculator 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 Tooth Eruption.

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 Tooth Eruption.
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 Tooth Eruption Timeline Calculator 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.

Tooth eruption calculator

A key concept referenced by the Tooth Eruption: Calculate expected primary and permanent tooth eruption dates by child age. Identify delayed eruption and when to refer.

Baby teeth timeline

A key concept referenced by the Tooth Eruption: Calculate expected primary and permanent tooth eruption dates by child age. Identify delayed eruption and when to refer.

Permanent teeth eruption

A key concept referenced by the Tooth Eruption: Calculate expected primary and permanent tooth eruption dates by child age. Identify delayed eruption and when to refer.

Dental development

A key concept referenced by the Tooth Eruption: Calculate expected primary and permanent tooth eruption dates by child age. Identify delayed eruption and when to refer.

Tooth Eruption Timeline Calculator

Formula Definitions

How to Use This Calculator

Glossary and Definitions

Related Calculators

Frequently Asked Questions