Table 8.
Summary of studies characteristics and results of the included studies assessing Class II headgear appliances.
| Reference | Sample | Outcomesa | Results | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline G1 | ΔG1b | Baseline G2 | ΔG2b | ΔG1 − ΔG2 | P-valuec | ||||
| Group 1 | Group 2 | Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | ||||
| Ngan et al. (36) | HPA | Untreated | MPA (°) | NA | 1.8 (2.1) | NA | 0.0 (2.1) | 1.8 | NS |
| n = 8 | n = 8 | SN.PP (°) | 0.8 (1.8) | 0.0 (1.0) | 0.8 | NS | |||
| 6♀/2♂ | 6♀/2♂ | ||||||||
| 10.2 yrs | Age-matched | ||||||||
| OP: 14 months | |||||||||
| Jacob et al. (24) | MTA | Untreated | MPA (°) | 35.9 (5.3) | −0.6 (1.6) | 36.2 (3.6) | −0.1 (0.9) | −0.5 | NS |
| n = 13 | n = 22 | NSPog (°) | 77.2 (5.1) | 0.2 (1.1) | 77.2 (3.0) | 0.3 (0.6) | −0.1 | NS | |
| 12♀/1♂ | 20♀/2♂ | SN.PP 2 (°) | 3.9 (3.4) | 2.1 (1.5) | 6.9 (2.7) | 0.0 (0.8) | 2.1 | P < 0.001 | |
| 8.8±0.7 yrs | 8.8±0.7 yrs | PP.MP (°) | 31.9 (4.6) | −2.7 (1.9) | 29.1 (3.4) | −0.2 (1.1) | −2.5 | P < 0.001 | |
| OP: 12 months | |||||||||
SD, standard-deviation; ♀, female; ♂, male; yrs, years; G1, group 1; G2, group 2; NS, non-significant; OP, observation period; NA, not available; HPA, high-pull activator; MTA, modified Thurow appliance; ΔG1, difference between final and baseline measurements for group 1; ΔG2, difference between final and baseline measurements for group 2; ΔG1 − ΔG2, difference between changes observed for groups 1 and 2.
aPre-treatment statistically significant (P < 0.05) differences on bold font, and absence of pre-treatment comparison on italic font.
bStatistically significant (P < 0.05) changes on bold font, and absence of intra-group comparison on italic font.
cConcerning ΔG1 − ΔG2.