Plaque · Adults undergoing orthodontic treatment
Aligners may reduce plaque index compared with fixed appliances in adults at 6-12 weeks (MD -0.58, 95% CI -0.82 to -0.34; very low certainty).
1 finding from 1 review
Lactobacilli presence (CFU > 10^5) · Adults undergoing orthodontic treatment
Aligners probably lower the risk of high lactobacilli counts versus fixed appliances in adults at 3 months (RR 0.09, 95% CI 0.02 to 0.47; low certainty).
2 findings from 1 review
Average fluorescence loss (dF%) · Adults undergoing orthodontic treatment
A single study reported lower average fluorescence (mineral) loss with aligners versus fixed appliances in adults at 3 months (MD -1.40, 95% CI -2.15 to -0.65; ungraded).
1 finding from 1 review
MD -1.40 [-2.15, -0.65]
1 study
GRADE not reported
Plaque · Adolescents/teenagers undergoing orthodontic treatment
A single study reported a lower full-mouth plaque score with aligners versus fixed appliances in adolescents at 12 months (MD -43.48, 95% CI -47.65 to -39.31; ungraded).
3 findings from 1 review
MD -43.48 [-47.65, -39.31]
1 study
GRADE not reported
MD -0.40 [-0.77, -0.03]
1 study
GRADE not reported
MD -14.78 [-16.74, -12.82]
1 study
GRADE not reported
Gingival index (GI) · Adolescents/teenagers undergoing orthodontic treatment
A single study reported lower gingival index with aligners versus fixed appliances in adolescents at 18 months (MD -0.57, 95% CI -0.93 to -0.21; ungraded).
1 finding from 1 review
MD -0.57 [-0.93, -0.21]
1 study
GRADE not reported
S. mutans presence (CFU > 10^5) · Adults undergoing orthodontic treatment
Aligners probably lower the risk of high S. mutans counts versus fixed appliances in adults at 3 months (RR 0.07, 95% CI 0.01 to 0.49; low certainty).
2 findings from 1 review
Gingival index (GI) · Adults undergoing orthodontic treatment
A single study found no significant difference in gingival index between aligners and fixed appliances in adults at 6-12 weeks (MD -0.10, 95% CI -0.35 to 0.15; ungraded).
1 finding from 1 review
MD -0.10 [-0.35, 0.15]
1 study
GRADE not reported
White spot lesions (WSLs), tooth level · Adults undergoing orthodontic treatment
A single study reported a lower risk of white spot lesions (tooth level) with aligners versus fixed appliances in adults at 3 months (RR 0.72, 95% CI 0.60 to 0.86; ungraded).
1 finding from 1 review
RR 0.72 [0.60, 0.86]
1 study
GRADE not reported
Percentage of bleeding on probing (BOP) · Adults undergoing orthodontic treatment
No clear difference in bleeding on probing between aligners and fixed appliances in adults at 6-12 weeks (MD -0.26, 95% CI -0.77 to 0.26; very low certainty).
1 finding from 1 review
Gingival inflammation-related index · Adolescents/teenagers undergoing orthodontic treatment
A single study reported lower simplified gingival index with aligners versus fixed appliances in adolescents at 1 month (MD -8.46, 95% CI -10.47 to -6.45; ungraded).
1 finding from 1 review
MD -8.46 [-10.47, -6.45]
1 study
GRADE not reported
Probing pocket depth (PPD/PD) · Adults undergoing orthodontic treatment
Aligners may reduce pocket depth compared with fixed appliances in adults at 6-12 weeks (MD -0.42 mm, 95% CI -0.71 to -0.12; very low certainty).
1 finding from 1 review
White spot lesions (WSLs), patient level · Adolescents/teenagers undergoing orthodontic treatment
A single study found no significant difference in white spot lesion formation (patient level) between aligners and fixed appliances in adolescents at 9 months (RR 0.33, 95% CI 0.10 to 1.04; ungraded).
1 finding from 1 review
RR 0.33 [0.10, 1.04]
1 study
GRADE not reported
S. mutans presence · Adolescents/teenagers undergoing orthodontic treatment
A single study found no significant difference in S. mutans presence between aligners and fixed appliances in adolescents at 1 month (RR 0.86, 95% CI 0.64 to 1.14; ungraded).
1 finding from 1 review
RR 0.86 [0.64, 1.14]
1 study
GRADE not reported
Full-mouth bleeding score (FMBS) · Adolescents/teenagers undergoing orthodontic treatment
A single study reported a lower full-mouth bleeding score with aligners versus fixed appliances in adolescents at 12 months (MD -20.44, 95% CI -22.98 to -17.90; ungraded).
1 finding from 1 review
Lesion area (decalcification area, pixels) · Adults undergoing orthodontic treatment
A single study reported a larger decalcification lesion area with aligners versus fixed appliances in adults at 3 months (MD 80.50 pixels, 95% CI 60.52 to 100.48; ungraded).
1 finding from 1 review
MD 80.50 [60.52, 100.48]
1 study
GRADE not reported
S. mutans counts (5th-root transformed) · Adolescents/teenagers undergoing orthodontic treatment
A single study found no significant difference in S. mutans counts between aligners and fixed appliances in adolescents at 1 month (MD -2.22, 95% CI -6.82 to 2.38; ungraded).
1 finding from 1 review
MD -2.22 [-6.82, 2.38]
1 study
GRADE not reported