Wearing the Tefillin Shel Rosh Over a Toupee
We read this article about wearing the Tefillin Shel Rosh Over a toupee and it’s so good to know that it’s acceptable to wear a permanent JK Hair Replacement System without causing a Hasisa and thus disqualifying the Misva.
As Rav Moshe explains that if a person undergoes a hair transplant, or has a permanent toupee that cannot be removed, then he may wear Tefillin normally over the implanted hair or toupee. Since it is placed permanently on the head, it is considered part of the head and does not constitute a Hasisa.
Read the full article here: http://www.dailyhalacha.com/m/halacha.aspx?id=2233