Digital Photography.
A shade tab records one value. A photograph records the relationship between that tab and the tooth beside it, which is what the ceramist actually works from.
Photograph before anything dries the teeth
Enamel dehydrates quickly once teeth are isolated or held open, and a dehydrated tooth becomes lighter and more opaque. A shade taken twenty minutes into an appointment can be a full step off the shade the patient will have once the tooth rehydrates, and the restoration is then permanently too light.
Take the shade and the photographs at the start of the appointment, before isolation, retraction or extended opening. If the case has already been under a dam, allow the tooth to rehydrate before assessing.
Put the tab in the frame
A photograph of the tooth alone tells the ceramist very little, because colour in an image depends on the light, the camera and the processing. A photograph containing both the tooth and the shade tab is self-referencing: whatever the lighting did, it did to both.
Hold the tab in the same plane as the tooth and immediately adjacent to it, not in front or behind, and make sure both are in focus. Photograph the tab you believe matches, and one on either side of it, so the ceramist can see which direction the match falls in.
Views worth taking
A retracted frontal view of the anterior segment for overall context. A close view of the tooth with the tab alongside. An incisal-edge view, which shows translucency, thickness and the shape of the incisal third better than any frontal image. And, for a case where the restoration will be visible in the smile, an unretracted portrait showing the lip line and how much tooth is actually displayed.
For anterior work, images of the adjacent teeth showing internal character — mamelons, white flecking, incisal halo, craze lines — are what make the difference between a restoration that matches in shade and one that matches in appearance.
Reduce the glare
Direct flash produces specular reflection that hides exactly the internal detail worth communicating. A cross-polarizing filter removes that reflection and reveals underlying chroma and internal structure, and for anterior aesthetic work it is the single most useful piece of equipment after the camera itself.
If cross-polarization is not available, angling the flash, using a diffuser, or moving slightly off-axis all help. Consistency matters more than sophistication: images taken the same way each time become a reference the ceramist learns to read.
Equipment that actually matters
The camera body matters least. What matters is the light source and the ability to control it, a lens that focuses close without distorting, and consistency between images.
A macro lens in the region of a hundred millimetres with a twin flash or ring flash, used at consistent settings, produces images the ceramist can learn to read. A modern phone camera with a clip-on diffuser and steady technique is considerably better than a good camera used inconsistently.
Retractors and a contrastor are the two accessories that change results most. A black contrastor behind the anterior teeth removes background reflection and makes incisal translucency visible in a way no amount of camera specification achieves on its own.
Standardize the series
The value of clinical photography compounds when the same images are taken the same way every time, because the ceramist develops a reliable sense of how your images relate to what is in the mouth.
A workable standard series is a retracted frontal view, a retracted close view with the shade tab in plane, an incisal-edge view with a contrastor, and an unretracted smile. Four images, the same four every time, taken before dehydration and sent unedited.
Adding a note about what you are trying to achieve turns the series into a brief. Photographs show the ceramist the situation; the sentence tells them what you want done about it.
The faults that recur
Shade tab out of plane with the tooth, so the two receive different light and the comparison is meaningless. Tab positioned in front of or behind the tooth rather than beside it. Images taken after prolonged retraction, with the teeth already dehydrated. Direct flash producing a specular highlight straight across the area of interest.
Then the processing faults: images auto-enhanced by the phone, brightened because they looked dark, cropped so tightly that the reference tab is lost, or compressed to the point where surface detail disappears.
Each of these is easy to avoid once it has been pointed out, and each individually is enough to make an otherwise useful photograph worthless as a shade reference.
Photographs do more than shade
Shade is the usual reason photographs are requested, but the images earn their place several other ways.
They record the pre-operative situation, which is the reference for anterior form, incisal position and tooth proportion once the tooth has been reduced. They document what the patient presented with, which matters if a result is later disputed. They show the technician the lip line and how much tooth is actually displayed, which changes where effort is worth spending. And they capture the adjacent teeth in a way no written description manages.
For a case being planned across several appointments, a consistent photographic record also lets you show the patient the progression, which is frequently more persuasive than anything said in the chair.
Send the images unedited
Do not colour-correct, brighten or filter clinical photographs. Automatic enhancement on a phone is doing the same thing invisibly, and both destroy the relationship between tab and tooth that made the image useful.
Send the originals at full resolution alongside the case, with a note explaining what you are trying to achieve. Photographs plus a sentence of intent are worth more than a long written shade description on its own.
In short
- Take shade and photographs before isolation — dehydrated enamel reads lighter
- Include the tab in frame, in the same plane as the tooth, plus one shade either side
- Take frontal, close, incisal-edge and unretracted smile views
- Cross-polarization removes specular glare and reveals internal character
- Send originals unedited and at full resolution
More on digital
Discuss a case
Where a case sits between options, a short conversation before preparation is usually quicker than resolving it afterwards.