Toilet comprising a collection body to collect physiological function excretions, defining a longitudinal axis and having an upper opening delimited by a perimeter edge and a lower opening configured to be connected to a sewer system, said toilet also comprising: - an annular body which delimits the collection body perimetrically and externally at said upper opening of said collection body; - an annular channel present in said annular body; - water supply means suitable to lead water in said annular channel to wash the inner surface of said collection body, said annular body comprising an upper ring outside which a seating surface is defined for the person using said toilet and a lower ring perimetrically fastened to the outside of said collection body and spaced from said perimeter edge, said lower ring being suited to define a perimeter band of said collection body which is comprised between said lower ring and said perimeter edge, is housed into said annular channel and is inserted in an annular slot formed between the upper ring and the lower ring, said annular slot being located at said upper opening and facing the inner volume of said collection body, wherein said annular channel comprises a concave area made in said upper ring, characterised in that the concave area is delimited by said lower ring, and said upper ring and said lower ring are removably joined together by connection means to define said annular slot. - an annular body which delimits the collection body perimetrically and externally at said upper opening of said collection body; - an annular channel present in said annular body; - water supply means suitable to lead water in said annular channel to wash the inner surface of said collection body, said annular body comprising an upper ring outside which a seating surface is defined for the person using said toilet and a lower ring perimetrically fastened to the outside of said collection body and spaced from said perimeter edge, said lower ring being suited to define a perimeter band of said collection body which is comprised between said lower ring and said perimeter edge, is housed into said annular channel and is inserted in an annular slot formed between the upper ring and the lower ring, said annular slot being located at said upper opening and facing the inner volume of said collection body, wherein said annular channel comprises a concave area made in said upper ring, characterised in that the concave area is delimited by said lower ring, and said upper ring and said lower ring are removably joined together by connection means to define said annular slot. said annular body comprising an upper ring outside which a seating surface is defined for the person using said toilet and a lower ring perimetrically fastened to the outside of said collection body and spaced from said perimeter edge, said lower ring being suited to define a perimeter band of said collection body which is comprised between said lower ring and said perimeter edge, is housed into said annular channel and is inserted in an annular slot formed between the upper ring and the lower ring, said annular slot being located at said upper opening and facing the inner volume of said collection body, wherein said annular channel comprises a concave area made in said upper ring, characterised in that the concave area is delimited by said lower ring, and said upper ring and said lower ring are removably joined together by connection means to define said annular slot.