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WEBVTT
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In Breaking Bad, one of the officers made a passing
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comment about how teeth can explode like popcorn in a fire.
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So it was the fifth season of Breaking Bad where
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investigators examined the remains of Gus Fring's industrial laundry, which
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concealed one of the most sophisticated meth labs in television history.
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Following the destruction of the lab, investigators confront a familiar
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forensic problem. Extreme heat has damaged human remains, including the teeth,
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raising questions about whether the victim can be identified. The
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dialogue suggests that teeth exposed to tremendous heat, like I mentioned,
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can pop like popcorn. But is that scientifically possible? Well, surprisingly,
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there is some legitimate science behind the claim. Human teeth
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are durable structures. Their outer layer, enamel, consists of approximately
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96% mineral by weight, primarily a crystalline substance called hydroxyapatite.
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This makes enamel the hardest substance in the human body. However,
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hardness does not mean resistance to every form of damage.
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When teeth encounter extreme temperatures, several physical and chemical processes
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begin occurring. First, moisture within the tooth evaporates. As temperatures increase,
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organic components from the dentin begin decomposing. The enamel and
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dentin also respond differently to temperature changes. This creates internal
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stresses that can produce fractures, cracking, and fragmentation. Under sufficiently
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extreme conditions, teeth can break into multiple pieces. So the
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popcorn comparison sound is not entirely ridiculous. However, teeth don't
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normally explode in the same way that popcorn kernels do.
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Popcorn pops because water trapped inside a relatively impermeable shell
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turns into steam, building pressure onto the shell ruptures. Teeth
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undergo a more complicated process involving thermo-expansion, dehydration, chemical decomposition,
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and structural weakening. If teeth are destroyed by fire, does
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that prevent investigators from identifying a body? Well, not truly,
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not necessarily. Forensic ortodologists specialize in identifying human remains through
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dental structures. Even severely burned teeth may retain recognizable characteristics. Fillings, crowns,
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root structures, and other dental features can sometimes survive the temperatures.
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Investigators can compare these structures against dental records, including radiographs
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obtained before death. And dental evidence is only one identification method. So,
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a particularly interesting aspect of Breaking Bad is that the
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lab explosion would not necessarily create uniform temperatures throughout the
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building either. Fire behavior depends on oxygen availability, fuel distribution, ventilation,
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and the surrounding materials. Some objects may experience incredible heat,
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while others remain relatively protected. Investigators might recover useful evidence
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from certain areas that appear completely destroyed. And there's one
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final scientific complication. Even when investigators recover fragmented teeth, they
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may sometimes reconstruct dental structures or identify distinctive restorative materials.
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The destruction of a tooth does not automatically eliminate its
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forensic value. So was Breaking Bad scientifically accurate? Well, partially.
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Extreme heat can unquestionably destroy teeth, and severe thermal damage
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can make dental ID extremely difficult. But the suggestion that
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teas simply pop like popcorn and become completely useless, that
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oversimplifies the science.