Brush head arrangements

A brush head (32) including: a plurality of bristle tufts (21), each of which comprises a plurality of bristle strands having a free end (25) and a proximal end (23); a plurality of retention rings (50) each comprising an upper portion (51), a lower portion (53), an exterior wall (55) and an interior wall (57), and each configured to receive the proximal end of at least one of the plurality of bristle tufts, wherein at least one of the plurality of retention rings comprises a transverse projection (71, 72) extending from the exterior and/or interior wall of the retention ring; and an elastomeric matrix (30) comprising at least a portion of each of the plurality of retention rings and the proximal end of each of the plurality of bristle tufts.