Dental patient chair with a pivotable backrest

A dental patient chair comprising a seat, a backrest, means for mounting the backrest for inclination on the seat, said means for mounting including a curved guideway with a first curved path for the seat and a backrest carrier adjustably moved toward and away from the seat, said backrest carrier being provided with a curved portion having a second curved path spaced from and discontinuous from said first curved path, approximate guide means on the seat and being allocated to the curved portion, the curved portion, curved guideway and guide means coacting so that the backrest carrier will be introduced under the seat when the backrest is inclined backward and is withdrawable from the seat when the backrest is inclined forward, the first curved path of the curved pathway of the seat and the second curved path of the curved portion of the backrest carrier being shaped and spaced from each other so that a momentary pole around which the backrest moves when being inclined is not constant but moves along a section of a curve forming a spiral that proceeds in the same direction as the inclined motion of the backrest.