Table 1.
Characteristics of included studies.a
| Study ID | Origin | Study design | Participants | Malocclusion | Study groups | Intervention | Outcomes | |
|---|---|---|---|---|---|---|---|---|
| 1 | Tehranchi 2018 [19] | Iran | Split-mouth design | 8 patients, 3 females, 5 males (30 extraction sockets). Age: 17.37 ± 12.48 years, range 12–25 years. |
Not recorded | Experimental side: extraction socket with L-PRF. Control side: no intervention, secondary healing. |
L-PRF clot | Space closure: horizontal linear distance between mid-marginal ridges of adjacent teeth, measured on study casts using a digital caliper. |
| 2 | El-Timamy 2020 [20] | Egypt | Split-mouth design | 15 female patients. Age: range 18 ± 3 years. |
Severe crowding or protrusion requiring first premolars extractions. | Experimental side: PRP injection with 10% CaCl2 activating solution. Control side: 10% CaCl2 injection only. |
PRP injection | Canine distalization: rate of canine retraction detected by change in canine position in superimposed models |
| 3 | Pacheco 2020 [21] | Brazil | Split-mouth design | 17 patients, 12 females, 5 males. Age: mean of 33 years, range 20–45 years. |
Angle Class I (14) or Class II Division 1 (3) malocclusion needing extraction of maxillary first premolars. | Experimental side: alveolus with L-PRF membranes. Control side: no intervention. |
L-PRF membrane | Canine distalization rate: monthly distalization rate of maxillary canines measured using a flexible ruler placed at dental midline from maxillary central incisors to mesial surface of canines. |
| 4 | Çağlı Karcı 2021 [22] | Turkey | Split-mouth design | 12 patients, 7 females, 5 males. Age: 16.45 ± 0.27 years. |
Angle Class II malocclusion with dentoalveolar protrusion or moderate crowding. | Experimental side: PRF injection. Control side: no intervention. |
PRF injection | Canine distalization and space closure: amount of canine distal movement and closure extraction space in superimposed dental model scans. |
| 5 | Erdur 2021 [23] | Turkey | Split-mouth design | 20 patients, 12 females, 8 males. Age: 21.4 ± 2.9 years. |
Angle Class II Division 1 malocclusion requiring maxillary first premolar extraction. | Experimental side: PRF injection. Control side: sham injection. |
PRF injection | Canine distalization: distance between midpoints of vertical lines drawn from incisal edge to cervical line over marginal ridge of lateral and canine teeth on dental cast measured by digital caliper. |
| 6 | Karakasli 2021 [24] | Turkey | Parallel | 40 patients, 23 females, 17 males. Age: 20.7 ± 1.45 years. |
Angle Class II Division 1 malocclusion requiring maxillary first premolar extraction and incisor retraction. | Experimental group: PRF injection. Control group: no intervention. |
PRF injection | Incisor retraction: linear distance between distal contact point of lateral incisor and mesial contact point of canine on plaster models recorded with a digital caliper. |
| 7 | Zeitounlouian 2021 [25] | Syria | Split-mouth design | 21 patients, 15 females, 6 males. Age: 20.85 ± 3.85 years, range 16–28 years. |
Angle Class II Division 1 requiring extraction of maxillary first premolars. | Experimental side: PRF injection. Control side: no intervention. |
PRF injection | Canine distalization: distance between medial end of third palatal rugae and cusp tip of upper canine. |
| 8 | Joy 2021 [26] | India | Split-mouth design | 15 patients, 9 females, 6 males. Age: 21.7 ± 2.52 years. |
Any malocclusion requiring lower first premolar extraction and canine retraction. | Experimental side: PRP injection. Control side: no intervention. |
PRP injection | Canine distalization: distance between mandibular canine cusp tip and first molar central fossa evaluated using digital Vernier caliper. |
| 9 | Angel 2022 [27] | India | Split-mouth design | 10 patients, 6 females, 4 males. Age: 19.05 ± 3.3 years, range 16–24 years. |
Bimaxillary protrusion or Angle Class II division 1 malocclusion requiring maxillary first premolar extraction. | Experimental side: PRP injection. Control side: no intervention. |
PRP injection | Canine distalization: rate of canine movement assessed using digital model superimposition. |
| Study ID | Measurement time | Primary results | Additional outcomes | Conclusions | Level of evidence | |
|---|---|---|---|---|---|---|
| 1 | Tehranchi 2018 [19] | T0: before placement of L-PRF. T1-T8: every 2 weeks during 2–16 weeks after study commencement. |
The linear distance decreased more in experimental side, experimental group showed higher rate of OTM (P = 0.006). | Not recorded | Application of L-PRF may accelerate OTM, particularly in extraction case. | Moderate |
| 2 | El-Timamy 2020 [20] | T0: before canine retraction. T1-T4: monthly until 4th month. |
Rate of canine retraction was faster on intervention side in first 2 months (T0-T1: P = 0.049, T1-T2: P = 0.772), but slower in 3rd month (P = 0.02). Total distances of both groups in 4 months were similar (P = 0.895) | 1. Canine rotation was comparable, with a mean difference of 1.036° (P = 0.71). 2. Pain increased following each injection without difference between two groups. |
PRP injection increased OTM during early stages (first 2 months), but did not exhibit long-term acceleration effects. Repeated PRP injection to maintain a steady accelerated OTM warrant further investigation. | High |
| 3 | Pacheco 2020 [21] | T1: beginning of retraction phase. T2: end of fifth month. |
Mean distalization rate was 0.909 mm/mo (95% CI, 0.8–1 mm) in control side, while 0.668 mm/mo (95% CI, 0.6–0.7 mm) in experimental side (P = 0.004). Difference was 0.23 mm/mo (95% CI, 0.07–0.39 mm). | 1. Canine inclination was greater on control side (8.57 ± 3.07°) than experimental side (5.81 ± 3.09°) treated with L-PRF (P = 0.001). | L-PRF decreased the distalization rate of maxillary canines in young adult patients. | Moderate |
| 4 | Çağlı Karcı 2021 [22] | T0: first premolar extraction and onset of canine distalization. T1-T6: every 2 weeks of 12 weeks after onset of canine distalization. |
Experimental side exhibited greater canine distal movement than control side (P = 0.011), as the same tendency as the amount of closure extraction space at T0-T1 (P = 0.018) and T0-T6 (P = 0.049) | 1. There were no difference in molar mesialization, canine rotation, transversal measurements (P＞0.05). 2. Periodontal parameters (plaque index, gingival index, probing depth) showed no difference (P＞0.05). |
PRF accelerated OTM. | Moderate |
| 5 | Erdur 2021 [23] | T0: before tooth extraction. T1-T4: 1, 4, 8, 12 weeks from beginning of distalization. |
Study group has higher rates of canine movement at all time points, and a higher total movement (6.06 ± 0.29 mm) than control group (3.89 ± 0.34 mm) (P＜0.001). Mean movement increased in weeks that PRF was injected (P＜0.001). | Not recorded | PRF injection facilitated OTM and shortened treatment duration by stimulating expression of inflammatory cytokines. | Moderate |
| 6 | Karakasli 2021 [24] | T0: before incisor retraction. T1–T4: 1–4 weeks after incisor retraction initiation. |
Study group showed higher weekly and total incisor movement than control group (P＜0.001). Incisors moved faster in T1-T0 and T3-T2 intervals (P＜0.05) | Not recorded | PRF injection increased rate of maxillary incisor retraction and shortened treatment duration. | Moderate |
| 7 | Zeitounlouian 2021 [25] | T0: before canine retraction. T1-T5: monthly up to 5 months. |
Monthly rate of canine retraction on experimental side were greater at T2, T3 and T4, but only significant at T2 (P = 0.018). Total movements were comparable (P = 0.918). | 1. Molar mesialization and canine rotation showed no difference at all time points (P＞0.05). 2. Overall duration of canine retraction between experimental (3.28 ± 1.00 months) and control (3.57 ± 1.16 months) sides was not significant. |
Rate of canine retraction was not significantly greater on experimental side than control side except at 2 nd month. Repeated PRF injection might be needed but merit more researches. | High |
| 8 | Joy 2021 [26] | T0: before canine retraction. T1: at completion of retraction. |
Rate of canine retraction for PRP group and control group was 0.87 ± 0.12 and 0.7 ± 0.13 mm/mo, respectively (P＜0.001). | 1.Overral duration canine retraction for PRP group and control group was 5.96 ± 0.94 and 7.42 ± 1.12 months, respectively. | PRP injection accelerated OTM rate by 1.24 times. | Moderate |
| 9 | Angel 2022 [27] | T0: before canine retraction. T2-T3: 30 or 60 days. |
OTM rate on PRP side increased by 35% in first month (P = 0.001) and by 14% at the end of second month (P = 0.015). | Not recorded | Local administration of PRP increased OTM rate during 60-day period. | High |
a
L-PRF, leukocyte platelet-rich fibrin; OTM, orthodontic tooth movement; PRF, platelet-rich fibrin; PRP, platelet-rich plasma.