Figure 4. Individual resting lip-pressure values in relation to the level of the lip line (n = 42). (A) Pressure in the incisal area of the upper centrals, (B) pressure in the cervical area of the upper centrals, and (C) weighted average of incisal and cervical pressures. Different symbols indicate to which study group the subjects belonged. In each diagram, linear regression curves were separately calculated for the Class I group (n = 21, dashed lines) and the Class II, Division 2 group (n = 21, solid lines). The formulae of the curves are included in the diagrams. In the statistical evaluation, no significant inter-group differences in the slope and position of the regression curves could be found (ANCOVA, p > 0.19).
