4 Vital Images For Your Dental Lab

So, you have been reading and learning what photographs you need to take for you and your patient so you can make a proper diagnosis and take them on a tour of their mouth. 

That’s it, right? I mean, what other pictures could you need? Well, don’t forget your laboratory technician! 

Sure, they will love all the photos you took at your exam (at least they should) but chances are they will be able to do a better job for you and your patient if you send them a few extra images. In this article, I will cover four “extra,” although we really shouldn’t call them extra as they are more like vital images for your lab.

Full Face, Lips Retracted, Teeth Apart

This one’s huge! If you ask Bob Winter, he will tell you this image is his favorite since it tells nearly the whole story and lets us compare the interpupillary line and the occlusal planes of both arches to horizon. My ceramist LOVES this image, so for me, this one is a must!

One key that I like to emphasize with this image is having a known horizontal reference (like the level picture frame in this example) or perfectly vertical reference in the image. For even more tips on setting up this image you can head here.

Pre-operative Shade

Sure, you can just write down which shade you want and heck, if you are doing a full mouth that might be OK; but if you are trying to match color, you are going to be way better off with a well-taken shade photograph. The biggest tip I can give you here is that you need to nail the exposure and position of the shade tab.

OK, so I said you have to “nail” the exposure. While that is of course ideal, I will add that if you are going to err, do so by slightly underexposing the image as you can recover from that to some degree as compared to an overexposed image. In this case, you have lost way more information but even worse, you are often times sunk. 

Beyond proper exposure, you also need great shade tab position. The key here is to have the tab exactly the same distance from your flash as the teeth you are referencing.

Again, precision is vital. If your tab is closer to the flash than the teeth are, it will get more light than the teeth. If the tab is further from the flash, it will get less light than the teeth. Either way, you will not have the most accurate images that show what you want and your lab needs.

One more thing! Notice I said pre-operative shade photo when I described this image. Do not forget you need to take this image at the VERY start of your procedure, before you do anything else! 

The reason is that you do not want the teeth to dehydrate (which they will do as you work), since they will then appear lighter and your color match will be off.

Cross-polarized Shade

This can be an optional image depending on your ceramist, but I can tell you my ceramist and I love this image. The purpose of this image is to help him see even more detail by eliminating any reflections from the flash. It almost lets him see below the surface. 

To get an idea of what this does, take a look at the image below. It is the same image I referenced for the pre-operative shade example above, but it was taken with my polar_eyes filter in place, which provides this cross-polarization.

If you are sayin​g to yourself, “uh...that’s not showing me much,” I agree. This is not the best example of the value this image can have, since the existing crowns do not have a ton of character. It does, however, illustrate the difference in the image you get with the filter in spite of the fact that it does not give you tons of extra information in every case.

For an example in which we do get tons of information, contrast that example to this case! Here is the pre-operative shade photo.

And now the cross-polarized photo:

As you can see, we can see additional character and how we might want/need to layer and characterize the restorations.

I will say that not every lab will find this image useful; furthermore, as you have seen above, it will be more useful in some cases than others.

So before you spend money on the polar_eyes filter or invest your time and effort into building your own version (which, yes, you can do), I recommend you make sure your lab will find it useful, since getting this image will require you to invest in new equipment.

There are lots of ways to adapt filters to your camera to get cross-polarized images. Perhaps the easiest is the use of a filter for your camera from a company called polar_eyes, which you can pick up from Photomed.  

Preparation Shade

You might also call this a “stump shade,” but please don’t ever call it that with a patient! As Gary says, they will saying to themselves, “stumps? I have stumps?” As you can imagine, they will probably not have a good image in their mind!

Given this, we always call this a preparation shade in my office so we have one consistent name we always use, even when patients are not present. The same rules apply here as with the preoperative shade photograph when it comes to position of the shade tab. It needs to be in the same plane as your preparation so it gets hit by the same amount of flash.

Typically, your lab will want you to use special shade tabs (as you can see above) that correlate to material they have to make custom-colored dyes so they can best simulate the preparation shade, so ask yours what they would like.

Just like the cross-polarization image, this image will provide lots of critical information for some cases, while it will be less critical for others.  For example, if you are using a material with a lot of light transmission, you’d better have a good image of the preparation shade. If, on the other hand, your restoration will completely take the preparation change out of play – say, for instance, a PFM with a 360-degree metal margin – then it might not matter after all.

In closing, thanks for taking the time to read this. Now get with your lab and set some time to discuss these images and which of them they would find useful so you can keep elevating the care you provide for your patients!

(Click this link for more dentistry articles by Dr. John Carson.)

John R. Carson, D.D.S., P.C., Spear Visiting Faculty and Contributing Author - www.johncarsondds.com