Bite Variations Lab#__ Name:__________________________________

IntroductionThe arrangement, size and alignment of human teeth are individualistic to each person. Since a person’s DNA contains the code for teeth development and arrangement, this is a reflection of genetic variation in human DNA.

In this lab we will explore the variation of teeth patterns in our class and compare similarities and differences in our measurements.

Q1: What teeth are your cutting teeth?_________________________________________________

Q2: What teeth do you chew your food with the most?____________________________________

Materialso 1 Styrofoam Bite Plates (7cm x 7cm)o 2 Transparency Plates (7cm x 10.5cm)o 400 ml Beaker with soapy watero Extra fine point permanent markero Ruler o Transparent tape

Procedure1. Obtain a clean Styrofoam bite plate and insert it into your mouth between your teeth. Make sure you

insert it until you feel it just touch the back of your mouth where the upper and lower jaws meet.

2. Bite down firmly, but not excessively, and then open your mouth and remove the bite plate. Make sure you keep track of which side has the impression from the upper teeth.

3. While maintaining your hold on the bite plate swirl it for 10 seconds in a bath of soapy water and then rinse thoroughly with tap water. Now gently blot the bite plate dry with a paper towel, making sure it is completely dry.

1K. LaCelle, Modified CIBT Lab

4. Lay a clear transparency film over the upper bite plate surface. Using a black extra-fine point permanent marker carefully trace the outline each tooth – take your time. Label with your name and “UPPER”!

5. Lay a clear transparency film over the lower bite plate surface. Using a black fine point permanent marker carefully trace the outline if each tooth. Label with your name and “LOWER”!

DATA:

Your upper bite cast is the Maxillary Impression and the lower bite cast is the Mandibular Impression.

Using the diagram at left, measure and record your bite mark data in mm:

1. Upper Intercanine Width (A)_____________________

2. Upper Arch Length (C) __________________________

3. Lower Intercanine Width (A)______________________

4. Lower Arch Length (C)___________________________

2K. LaCelle, Modified CIBT Lab

Your Upper Bite PlateTransparency

Your Lower Bite PlateTransparency

Examine your teeth in a mirror. Make a note of any variations you find in your own teeth such as cavities, fillings, chips, extra teeth, missing teeth, etc.

Check off all that apply and make a note on the diagram above:

� Missing tooth? (How many?__________________)

� Cavities? (How many?__________________)

� Fillings? (How many?__________________)

� Chipped tooth? (How many?__________________)

� Discolored tooth? (How many?__________________)

� Baby tooth? (How many?__________________)

� Extra tooth? (How many?__________________)

� Braces?

� Other?______________________________________________________________________

Q3: What differences did you notice between your bite mark/teeth and your partner’s bite mark/teeth? Compare and contrast your measurements A and C, as well as your observations.

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_______________________________________________________________________________________Class Data:

Upper Intercanine Width Lower Intercanine Width

3K. LaCelle, Modified CIBT Lab

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Scatter plot of Class Upper Intercanine Width/Lower Intercanine Width

Q4: What causes variations in the bite marks and teeth of humans? (just bullet)

4K. LaCelle, Modified CIBT Lab

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Q5: The diagram at right shows a child’s teeth pattern compared to an adult’s teeth pattern.

Why do you think we lose teeth as a child and have fewer teeth as a child?

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Q6: What do you think controls how our teeth develop and how our bite pattern forms?

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5K. LaCelle, Modified CIBT Lab