You can take standardized photographs with a scale (at standard distance, and angle etc;) Later you can measure the exact area (using any of the standard methods - or print it in 1:1 size and use graph paper method).

The problem is with depth measurement, difficult location, inaccessible / invisible / tissue distortion due to stretching / retraction etc; (but if you use standardised methods in every way and even for retraction you can get accurate results)

Intraoral digital imaging can also be used provided you use standardized method (using same protocol for every lesion every time!)

The problem of retraction and distortion still exist.

In essence, a suitable way to get the wound/lesion into a digital image which can later be processed for measurement of area is the idea published at: http://www.ncbi.nlm.nih.gov/pubmed/10760725

The idea is that the measurement must be reproducible and have intra and inter observer accuracy / reliability. But what you are measuring and how you measure the edges / extent of the lesion is important - in other words, the exact definition of the extent of the lesion is important. For example certain ulcers the healing edges would appear reddish (the new epithelium is almost imperceptible) and may extend for a couple of millimeters. Which of the edges is considered normal needs to be defined per lesion (it may vary for ulcers and patches to macular lesions to pustules etc;)

So unless you define it exactly, there can be variability which becomes a problem later. Standardisation is the key. And most importantly, TRY out. Write out a method, try it yourself and give the method to your friend to measure the SAME lesion to see what differences you get and what needs to be modified / standardized etc; (Pilot study!!!)

There appears to be a technique with optical spectroscopy for depth measurement:

http://onlinelibrary.wiley.com/doi/10.1002/cncr.24177/full

An idea would be to read literature on diabetic ulcer research of which some MAY be adaptable to oral wounds (not all as lesions in diabetes are easily accessible and visible!)

If you are interested in discussing more, feel free to write a message to me or email me.

And if you find any better methods, please do share it here for the benefit of all.

Regards,

Dr. Akilesh. R

drakileshr [at] akilmaxac [dot] com

Thank you Sir, this was quite comprehensive and exactly what I was looking for:), surely I have a lot to learn and if I bump into or may be even develop a better method, will share here!

Please see link on the importance of reliability and validity. You need to calibrate examiners. Just an idea to test if the lesions are regressing is to use a range for width of lesions and grade it from 0 to 3 eg. 0=no lesion, 1= 1-3 mm and so on. You can use the perio probe to measure which is cheap and simple.

http://www.icd.org/content/publications/WHO-Oral-Health-Surveys-Basic-Methods-5th-Edition-2013.pdf

Great! Thanks for the tip and the link sir!

Intraoral digital imaging  can be used.

Big problem with photos is foreshortening. Even with overlaid grid.

For most intra-oral lesions, and indeed many facial skin lesions, a pair of calipers and a metal ruler is hard to beat. You can measure the maximum dimension, or measure it in as many directions as you wish (which you can note in your records or on a photo). If extreme accuracy is not needed,  college tweezers held apart by a finger between the limbs is often the easiest thing to hand.

On most occasions, measuring is undertaken for comparison. Photos are difficult to compare immediately and consistently. A measurement between the most anterior and most posterior aspect of an ulcer, is very quick and easy.

P

I don’t think that any of the answers so far really solve your problem.

Before trying to do so one would need to ask what and where you wish to measure and whether you wish to  make comparisons between patients or serially in the same patient. All of these matters are important.

First, what and where; if you wish to measure lesions on teeth, then that is exceptionally simple; just use a set of callipers (if you don’t have callipers, visit your orthodontic department and ‘borrow’ a set).

Second, if you are measuring lesions on a mucous membrane, then the relation of that tissue to the underlying bone and muscle is important. If the tissue is tightly bound down to bone, as in the attached gingivae and the hard palate, callipers will suffice again. If the tissue is firmly bound down to muscle, as in the dorsum of the tongue, there is minimal distortion as the tongue moves and it may be possible to establish a ‘standardised’ position that will be fairly reproducible is you are not looking for precision.

Other mucous membranes in the mouth are very distortable and capable of stretching in three dimensions. There is no simple way of making measurements on them. I have tried using a standardised frame for buccal photographs. This had a hollow mouth prop to maintain jaw separation at a standard amount (made specifically for each patient and located accurately by imprints of the occlusion) with an extension carrying a ring against which the camera was placed at a standard magnification. The best that can be said of that is that if it had worked, (and it didn’t, due to the prop masking areas that I wished to photograph) then it would have allowed me to compare the size of lesions from week to week, but would not have allowed me to make comparisons between patients.

I have considered trying to measure cheek lesions using impression material. A slim ‘tray’ covering the buccal aspect of the teeth, and held in place by an extension between the teeth (like a bitewing radiograph), would be coated with impression material and the cheek would be allowed to rest lightly against it. This would produce the least distortion and allow inter patient comparisons, but only if the lesions have a third dimension (e.g. ulcers or a raised surface) that would record in the impression.

This is probably not very helpful but I am advising you not to start any project involving measurement before you establish a reproducible method.

Thank you Drs Patrick and Bernard. I surely will consider investing in a pair of calipers. Also @Dr. Patrick, thanks for the tweezer improvisation trick *thumbs up*... Still am looking for something really accurate. @Dr. Bernard, I'm highly grateful to you for sharing your novel 'attempts'. I have a doubt/suggestion (which ever way you'd like to take it) regarding the innovative mouth prop you described... Was it not possible to place the prop on the side contralateral to the one you wanted to photograph?! Also Dr. Bernard,  the impression method you've adopted is really interesting, could you share some of your findings and clinical pictures here if possible?!

To start with take scaled standard photograph with identical angle and magnification.

Use a simple software to measure the dimentions and surface size  and compare after 20, 72, h and 1 week, to see if the lesion size is reduced or increase. If there is an increase or no change after 7 days you must observr the detoth or hight too.

Thank you Dr. Haim Tal

Sure Dr, how to go about it?