Instructions, Technique and Schedule:
Anatomy of a Properly Taken Toothprints
Thermoplastic Bite Impression from the MDS Journal
DAVID A. TESINI, DMD, MS, FDS RCSED
DAVID B. HARTE, DMD
Dr. Tesini is associate clinical professor at
Tufts University School of Dental Medicine. He maintains a
pediatric dentistry/ orthodontic practice in Natick. He patented
Toothprints in 1986. Dr. Harte is founder and national
spokesperson for the MasoniCHIP Program and a member of the
Massachusetts Dental Identification Response Team. He maintains a
practice in Milton.
bite impression technique, like most procedures in clinical
practice, is technique sensitive. The biometric information
available from the thermoplastic wafer is directly proportional to
the care with which the technique is performed, as well as the
cooperation and understanding of the child. Although the amount of
information and the detail we obtain with the impression of only a
few teeth (tooth size and occlusal anatomy are able to be
digitized to 50 microns), along with saliva for scent dog tracking
and cellular DNA analysis, it is a properly taken full-arch bite
impression that would provide the best opportunity for infinite
concordant matches for identification, should the need arise (see
Figure 1). With that in mind, below are the steps for properly
taking a full-arch bite impression.
If possible, familiarize yourself with the
thermoplastic material and overview of the entire bite impression
technique prior to your participation in a sponsored CHIP event.
Information on the technique and the material can be found on
Bring either latex or
nitrile gloves, as those made from other materials may stick to
the wafer. Make sure that the temperature on the wafer bath is
preset to about 140�F. The Toothprints material should be just
about ready to �slump� but not too putty-like or soft. Show the
wafer to the child and explain the technique in terms the child
can understand. Remember your �Tell, Show, and Do� from dental
school? �Can you open big, big like a lion? Good. And then close
tight. Don�t open until I tell you. I�ll count to 10, okay?�
(Hint: Count slowly, until the wafer hardens.) Place the softened
wafer centered over the lower arch. (If you�re standing behind the
child, with the child�s head tipped back, it may be easier to
position the wafer on the maxillary arch.) If the child is under
the age of four, you may want to squeeze the wafer arches together
or cut a few millimeters off of the back. Now, repeat the
child-friendly explanation inStep 3. The wafer should be firm
before removing. If the child bites and opens quickly, remove the
wafer as fast as possible and hold it flat in your hand until it
is firm. Wait 1-2 minutes for the water on the Toothprints wafer
to dry, and then place it in the ziplock baggie and seal. It can
be difficult to wait that 1-2 minutes when you have a line of 25
kids waiting, but it is important that the wafer be dry before it
is packaged and sealed. If the child is uncooperative, place a
nonsoftened Toothprints wafer in a ziplock bag, place the �Bring
to the Dentist� sticker on the bag, and give it to the parent with
instructions to bring it with the child to his or her next dental
visit so his or her dentist can take the Toothprints impression at
The Four Most Common Problems:
Lack of cooperation fromthe child. Don�t go
crazy; remember that CHIP is a community event.
Double biting, smudging, or grinding (see Figure
2). If one of these occurs, you should redo the impression, but
place both the first and second tries in the bag.
Arch not fully positioned on wafer (see Figure
3). If you think you can improve it, then try one more.
Wafer is too hard or softened too much from the
water bath (see Figure 4). You should redo the impression.
Properly taken, detailed Toothprints bite impression showing
full-arch dental characteristics.
Toothprints bite impression that has been poorly positioned,
double bitten, and smudged.
Figure 3. Toothprints bite impression that has not captured
the full dental arch.
Thermoplastic wafer not heated sufficiently prior to
Toothprints bite impressions can aid in the
recovery, identification, and prosecution for cases of lost,
missing, or unidentified children. Therefore, it is crucial that
the procedure be performed correctly to create a viable impression
that will increase the chances of identification and tracking, and
potentially, save lives
- Toothprints for Infant Identification to to
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