Q. I made Masah on a plaster on my hand. After I performed Salaah, I changed the plaster. Does my Wudhu remain valid?
A. In principle, Masah over a plaster/cast will remain valid until the wound etc. completely heals. In the process, if the plaster/cast is changed, it will not be necessary to repeat the Masah over the plaster/cast and the Wudhu will remain valid.
Upon the wound etc., completely healing, the Masah over the plaster/cast will not suffice and it will be necessary to wash the organ. (Jadeed Fiqhi Masaail 1/62)
Note: Masah over a plaster etc. will only be valid in the case of a valid Shari’ reason, for e.g. the wound etc. will not heal if the plaster is removed.
Allah Ta’ala Knows Best
Mufti Ismaeel Bassa
themufti.com