Which is the most effective when needing to use---sulcabrush or oral gum stimulator at end of toothbrush? like to hear from a dentist.

Depends: It all depends on the end-goal of the device being used. Gum stimulators are great for gum stimulation and overall gingival improvement, but will not remove plaque between teeth. Sounds to me like you may be trying to condense 2 different ideas into one. If so, it will not work properly. Remember, the gums support the teeth; good gums equal good teeth.

Doesn't matter: It's not so much the tool that matters, it's how you use it. Also different people have different needs, so what might work well for one person may not be the best for another. The important thing is to make sure you clean thoroughly. See your dental professional for advise. Bring whatever device you use to your next cleaning for a technique evaluation.