This Celiac.com FAQ on celiac disease will guide you to all of the basic information you will need to know about the disease, its diagnosis, testing methods, a gluten-free diet, etc. Subscribe to FREE Celiac.com email alerts What are the major symptoms of celiac disease? Celiac Disease SymptomsWhat testing is available for celiac disease? - list blood tests, endo with biopsy, genetic test and enterolab (not diagnostic) Celiac Disease ScreeningInterpretation of Celiac Disease Blood Test ResultsCan I be tested even though I am eating gluten free? How long must gluten be taken for the serological tests to be meaningful?The Gluten-Free Diet 101 - A Beginner's Guide to Going Gluten-FreeIs celiac inherited? Should my children be tested? Ten Facts About Celiac Disease Genetic TestingIs there a link between celiac and other autoimmune diseases? Celiac Disease Research: Associated Diseases and DisordersIs there a list of gluten foods to avoid? Unsafe Gluten-Free Food List (Unsafe Ingredients)Is there a list of gluten free foods? Safe Gluten-Free Food List (Safe Ingredients)Gluten-Free Alcoholic BeveragesDistilled Spirits (Grain Alcohols) and Vinegar: Are they Gluten-Free?Where does gluten hide? Additional Things to Beware of to Maintain a 100% Gluten-Free DietFree recipes: Gluten-Free RecipesWhere can I buy gluten-free stuff? Support this site by shopping at The Celiac.com Store.For Additional Information: Subscribe to: Journal of Gluten Sensitivity
Yes, definitely tell them. In intake forms, they will usually ask about allergies, and you can just list it there. Then, when the dentist reviews it and brings it up, you can mention that you need to check all products before they are used on you, etc. Easy!
One step that you can take is ask the ped. to test him for the genes associated with Celiac - HLA DQ2 and HLA DQ8. Over 95-98% of those with Celiac has one/both of the genes, so if he tests negative, then you know his risk for Celiac is dramatically lower than someone with the gene. Of course, having the gene does not mean he has Celiac, as 30-40% of the population has the gene. But, would be a good bit of information to you to have.
Of the tests you listed, the only test for Celiac is the tTG. The IgA/IgM/IgG -and IgG subclasses -(as you wrote it) are not Celiac tests per se, and are tests to see if you make enough of them or are deficient.