Disclosed are embodiments of a dental prophylaxis angle. One dental prophylaxis angle includes a body having a neck that defines a first axial bore and a head that defines a second axial bore, the first and second axial bores communicating at an intersection and being angularly- offset from each other , a drive gear rotatably mounted in the first axial bore and having a drive gear head and a locking flange axially- offset from the drive gear head , an annular locking groove being defined between the drive gear head and the locking flange , a driven gear rotatably mounted in the second axial bore and operatively coupled to the drive gear and a gear retainer having an annular body configured to extend about an outer surface of the head , a heel extending from the annular body , an arm extending from the heel , and a wedge extending from the arm.
