In major ablution (Ghosl) and minor ablution (Wuḍū), water must reach throughout the body and it is not allowed to create an impediment on the body that is difficult or impossible to remove, unless there is a necessity or a lawful rational motive in this issue.
Nevertheless, if an impedimentis created that it would be difficult or impossible to remove, performing Ghosl and Wuḍū with that impediment is correct.
Here is the answers of the Grand Authorities (Marajiʻ):
“In the case of the implantation of nail, the impediment must be removed even with the possible expense of money. Moreover, if the person knows that it is not possible to remove it; or it would entail an unbearable pain; or it causes to a considerable harm, they must perform Ghosl and Wuḍū at the time of prayer then they perform the prayer and they must perform the next ablutions over a splint (it means to wipe over the impediment with wet hand). If it would be possible to remove it – even in the next days – and they do not remove it, performance Ghosl and Wuḍū over a splint will be void.”
Ayatollah Makarem Shirazi:
“If there is not necessity in this issue it should be avoided because it is an impediment for Ghosl and Wuḍū. If there is a necessity [for implementing the nail] and there is no possibility to remove the artificial nails to perform Ghosl and Wuḍū, they should perform the ablutions over a splint (Jabirah ablution).”
“Before performing the Ghosl and Wuḍū, that which prevents water from reaching the parts of body must be removed.”
Ayatollah Safi Golpaygani:
“Implanting nail while the one cannot remove it for Ghosl and Wuḍū is not permissible. If a person has done this, they should remove it on the condition of possibility and perform Ghosl and Wuḍū in the usual way; but if it would be impossible to remove the artificial nails, they should perform Ghosl and Wuḍū with them and also they should perform dry ablution (Tayamom) as a precaution.”
“1 – The person who does not have nail and wants to implant artificial nails, that nail is not deemed as a part of their body because it does not grow. This implantation is not permissible from the beginning because it is not of necessity.
2 – It makes Ghosl and Wuḍū invalid. At the time of prayer, it would be deemed as spoilingthe obligatory order and before the time of prayer, it is contrary to the precaution. But if a person did so (nail implantation) and there would be no possibility to remove it at the time of Ghosl and Wuḍū, they must perform the ablutions over a splint (Jabirah ablution).”
Ayatollah Hadavi Tehrani:
“1 – In Wuḍū it is obligatory to wash the whole face and entire hands from elbow to fingertips and if an impediment prevents water from reaching the body, it must be removed. It is not obligatory to wash the part of nail that has been grown out of fingertip or the part of beard that is out of the round of face.
2 – In Ghosl, water must reach the skin and short hairs such as beard or eyelashes must be washed too.
3 – It is not permissible to create an impediment that is difficult or impossible to remove (it has difficulty and hardship); unless there is a necessity or a lawful rational motive such as treatment regarding this issue.
4 – It seems that the beauty is a lawful rational motive.
5 – If an impedimentwas created that it would be difficult or impossible to remove (it has difficulty and hardship); Ghosl and Wuḍū can be performed with that impediment, however making that impediment had not been permissible. Of course, it is also of recommended precaution to perform the dry ablution (Tayamom) too.
Related Link: Ijtihad Network