Variability in upper lip posture to overjet changes in 12-year-old Nigerian children.

Abstract

One thousand and sixteen 12-year-old Nigerian primary school children were examined for upper lip posture at different overjet values. Upper lip positions were assessed using the Jackson's criteria. The most common lip position was Jackson class 3 with 72 per cent. Positions 0 and 1 were not common features. Normal overjet value of 2-4 mm was found in 82 per cent of the sample population. The findings from this investigation also showed very little significant relationship between variation of overjet at different upper lip positions.