Is it permissible to fumigate with incense over which the Quran has been recited, and is that considered burning the Quran and the word of Allah?

The use of incense in ruqyah (exorcism/healing through Quranic recitation) has no basis in the Sunnah or from the Companions and the righteous predecessors. It is among the rituals of sorcerers.

Some believe that incense repels pests, is beneficial in ruqyah, undoes magic, and expels devils. This is among the beliefs of the Sabians, Christians, innovators, and polytheists.

It was narrated from Sheikh Al-Islam Ibn Taymiyyah that Christians burn incense at their graves and in their homes at specific times, believing that it brings blessings and repels harm, not because it smells good. They consider it an offering. And that many Muslims do this, having adopted it from them.

Sheikh Ibn Baz was asked about using incense to expel devils, and he said: "I do not know of any legal basis for this action, and it must be abandoned, as it is one of the superstitions that have no basis. Devils are expelled only by frequently remembering Allah, reciting the Quran, and seeking refuge with Allah's perfect words from the evil of what He created."

The basic principle regarding the use of incense is its permissibility because it is a pleasant fragrance used for perfuming with its smoke, and for no other reason. Legitimate ruqyah is sufficient and makes unnecessary recourse to suspicious methods.