Scintigraphic evaluation of 13 cases of submandibular duct sialolithiasis was performed to determine glandular function and to estimate the justification for sialoadenectomy. Twenty-two per cent of these glands showed no function despite sialolithectomy, which suggests that it would be reasonable to excise submandibular salivary glands that have no recovery of function. However, the remaining 78% of the glands showed varying degrees of recovery of function, indicating that sialolithectomy should be done first, followed by 99mTc-pertechnetate scintigraphic examination to determine the necessity of further sialoadenectomy.