Does a diamond placed for adornment on the teeth prevent water from reaching the skin?

The types of diamonds placed on teeth vary, and some might prevent water from reaching the tooth. However, this does not affect purity (tahara), because rinsing the mouth (madmada) is a sunnah in wudu' (ablution) and ghusl (ritual bath) according to the majority of scholars. Even those who deem it obligatory do not stipulate that water must reach every part of the mouth and nose. Water reaching under dental fixtures and adhesive material is excused due to hardship and difficulty (haraj and mashaqqah), and merely passing water over them is sufficient.