Teeth are incredibly durable structures made up of multiple layers of mineralized tissues. However, when exposed to extreme heat like in a fire, teeth can be damaged or destroyed. Here’s a closer look at how teeth respond to fire and heat.
How teeth are impacted by fire
When teeth are exposed to high heat, the different structures that make up the tooth respond differently:
- Enamel – This outer layer is made up mostly of hydroxyapatite crystals. Enamel will crack, char, and fracture when exposed to temperatures above 600°C.
- Dentin – Softer than enamel, dentin contains more organic material. Around 300-400°C dentin will char and turn brown or black.
- Pulp – The soft tissue inside the tooth is very sensitive to heat. It will coagulate and die rapidly above 60°C.
So while the hard mineralized outer layers can withstand some heat, once temperatures rise above 300-400°C, the internal pulp tissue dies and the tooth structure becomes severely compromised. Prolonged exposure to extreme heat leads to carbonization and complete breakdown of the tooth.
Factors that influence heat damage
Several factors influence the extent of damage teeth incur when exposed to high heat:
- Temperature – The higher the temperature, the more quickly damage occurs.
- Duration – The longer the exposure, the more in-depth the effects.
- Moisture – Drier teeth absorb heat slower than moist teeth.
- Tooth structure – Enamel protects dentin but is vulnerable once cracked.
Effects of fire damage
The effects of heat exposure depend on the severity of damage:
- Mild cracking/charring – This may only require minor restoration like bonding or veneers.
- Partial internal necrosis – The pulp chamber is affected and root canal treatment is likely needed.
- Severe structural damage – The tooth requires extraction and prosthetic replacement.
- Carbonization – Total breakdown means the tooth needs to be removed.
Identifying burnt teeth
Exposed to high heat, teeth may display:
- Cracking and crazing of the enamel
- Black or brown discoloration
- Distortion of shape
- Fractures exposing inner layers
- Total charring/calcification
Dental evidence in fires
Forensic odontologists analyze burnt teeth recovered from fire scenes to identify human remains. Dental features that may survive fires include:
- Enamel thickness
- Unique fillings/dental work
- The pattern of tooth eruption and development
- Sinus and bone patterns
In mass disasters dental records are crucial for identifying victims when other means are impossible. Teeth offer unique features even when severely burnt.
Protecting teeth from fire damage
It’s extremely difficult to fully protect teeth from fire damage. However, firefighters wear special helmets and masks to shield their face, mouth, and teeth from excessive heat when working in close contact with flames. For those unexpectedly caught in fires, covering the mouth with a wet cloth may provide minor insulation.
Survival of dental remains
Due to their hardness, teeth are often the only survivors of cremation and incineration. But at typical cremation temperatures between 1400-1800°F, even dental enamel will eventually calcify and warp. After cremation, teeth may even explode or fragment due to trapped moisture. Still, cremated remains will usually contain identifiable tooth fragments.
Conclusion
While incredibly durable under normal conditions, teeth are still vulnerable when exposed to extreme high temperatures. Prolonged or intense heat will damage tooth structure, initially charring the enamel before progressing to internal changes. But due to their hardness, teeth may survive fires even when nothing else remains, giving crucial identity clues when traditional methods fail.