Human Teeth Model, Upper and Lower Jaw

Quick Answer: The human teeth model, upper and lower jaw, is an upper and lower jaw teeth model: both dental arches with their teeth and gums, arranged so the two rows meet as they do in the mouth. It is used to teach the complete dentition, occlusion (the bite) and tooth numbering in dental, nursing and biology courses.

Both Arches and How They Meet

A model with only the lower jaw can teach tooth order, but it cannot show the bite. With both jaws together, students can see how the teeth of one arch fit against the other. In a normal bite the upper front teeth overlap the lower ones slightly, both vertically (overbite) and horizontally (overjet), and the upper arch sits a little outside the lower arch all the way round, so the cheek-side cusps of the upper back teeth rest outside those of the lower back teeth.

The key relationship orthodontists look at is between the first molars. In what Edward Angle called Class I, the front cheek-side cusp of the upper first molar lines up with the groove on the cheek side of the lower first molar. When the lower molar sits further back than this, the bite is Class II, and further forward it is Class III. A model with both jaws makes these descriptions concrete before students meet plaster study casts.

A full adult set has 32 teeth, 16 in each jaw: in each quarter two incisors, one canine, two premolars and three molars. Whether this model is hinged, shows the roots through a clear gum or has removable teeth is not stated in the title, so those features should be checked before ordering.

Specifications

Applications

• Teaching occlusion, overbite and overjet in dental and orthodontic foundation courses
• Practising tooth numbering systems such as FDI and Universal on both arches
• Demonstrating brushing of the biting surfaces and gum line on upper and lower teeth together
• Explaining malocclusion classes before students work with plaster study models

Care & Handling

• Close the jaws gently; if the model is hinged, do not force it past its natural opening, since the joint pins are the usual failure point.
• Wipe the teeth and gums with a soft damp cloth after demonstrations and let everything dry before closing the jaws.
• Keep the upper and lower jaw teeth model boxed when not in use so cusps and incisor edges are not chipped.

Why Choose LabEquip

Dental hygiene tutors, orthodontic foundation courses and school health teams choose a two-jaw model when the bite itself is the lesson. It sits in LabEquip’s biology lab products next to the single-arch lower jaw teeth model; send quantities or questions about hinges through the LabEquip contact page.

Frequently Asked Questions

What is the difference between overbite and overjet?

Overbite is the vertical overlap, meaning how far the upper front teeth cover the lower front teeth when the back teeth are closed together. Overjet is the horizontal distance from the front of the lower incisors to the edge of the upper incisors. Both are small in a normal bite.

What are Angle’s classes of occlusion?

They describe how the upper and lower first molars meet. Class I is the normal relationship, Class II has the lower molar further back and Class III has it further forward. The classes are the starting point for describing most orthodontic problems.

How many teeth are in each jaw?

An adult with all wisdom teeth present has 16 permanent teeth in each jaw: four incisors, two canines, four premolars and six molars. A child’s primary set has 10 teeth in each jaw, with no premolars.

Why does the upper arch sit outside the lower arch?

The upper arch is slightly wider, so its back teeth close over the outer cusps of the lower teeth. This lets the cusps interlock for grinding, and the overlap helps protect the cheeks and tongue from being bitten. When a lower tooth sits outside its upper partner, the bite is called a crossbite.

How are teeth numbered on a model?

In the FDI system each tooth has two digits: first the quadrant (1 upper right, 2 upper left, 3 lower left, 4 lower right), then its place counting back from the midline, 1 to 8. So 11 is the upper right central incisor and 36 the lower left first molar.

Can this model be used for brushing demonstrations?

Yes. With both jaws present, a presenter can show brushing of the inner and biting surfaces of the upper teeth as well as the lower ones, which a single-arch model cannot do. Use a soft brush and water only, since toothpaste lodges between the teeth.

Last Updated: September 2026