Evaluating the efficacy of platelet-rich fibrin in accelerating canine retraction following upper first premolar extraction: a split-mouth randomized controlled trial

Abstract

Background:

While recent studies have explored the use of blood-derived materials to expedite orthodontic tooth movement, their efficacy remains a subject of debate, with conflicting results reported in the literature.

Objective:

The objective of this randomized controlled clinical trial is to assess the efficacy of platelet-rich fibrin (PRF) in accelerating the distal movement of maxillary canines subsequent to the extraction of the first premolars and to determine patient satisfaction with the treatment.

Materials and methods:

A randomized controlled clinical trial using a split-mouth design was conducted on 20 patients (12 female, 8 male). One side of each patient’s mouth received an immediate post-extraction application of PRF, while the contralateral side served as a control. Canine retraction velocity and anchorage loss were evaluated using gypsum models; speed of movement was measured at monthly intervals. Patient-reported outcomes were collected using Visual Analog Scales at 1-, 3-, and 7-days post-extraction. A t-test (with 95% confidence level) was used for statistical analysis.

Results:

A statistically significant difference was observed between the control side and the study side (where PRF was applied) regarding the speed of upper canine movement during the first and second months, as well as over the entire evaluation period (T0–T3). The probability value was less than 0.001 for each of these periods. However, no significant difference was noted between the two sides during the third month. By analyzing the algebraic sign of the differences between the averages, it was concluded that the speed of upper canine movement was greater on the side where PRF was applied compared to the control side. Regarding the mesial movement of the upper first molar (anchorage loss), the loss of anchorage was slower on the PRF application side compared to the control side across all evaluation periods, though the differences were not statistically significant, as the probability value exceeded 0.05 at the 95% confidence level. Additionally, a statistically significant difference was observed between the control and PRF application sides for the variable of pain. This difference was noted 1 day after the application of PRF within the socket during orthodontic treatment, as well as on the third day, with probability values of 0.0052 and 0.0066, respectively. However, no significant difference in pain levels was observed between the two sides on the seventh day after fibrin application compared to the control side, as the probability value was greater than 0.05 at the 95% confidence level.

Conclusions:

The use of PRF in the extraction socket was found to accelerate the movement of the upper canines during the first and second months compared to traditional extraction methods. Additionally, the application of PRF significantly reduced pain levels following the extraction procedure.

Introduction

Adult patients often prioritize faster orthodontic treatment to minimize disruptions to their social and professional lives, reflecting a growing emphasis on aesthetics and efficient time management^[1]. Consequently, numerous methods for accelerating orthodontic treatment have been explored, with surgical approaches being among the most widely studied and utilized due to their predictable and stable outcomes^[2]. However, these surgical techniques are considered invasive, requiring extensive elevation of palatal and lingual mucoperiosteal flaps and significant cortical bone removal^[3,4]. This necessitates the development of less invasive approaches to enhance tooth movement speed and reduce treatment duration^[5].

Orthodontic tooth movement involves the application of force that initiates remodeling in the periodontal ligament and alveolar bone. This process includes resorption on the compression side, characterized by the formation of a hyalinized zone, osteoclast activity, and bone formation on the tension side by osteoblasts^[6]. Orthodontic forces trigger an inflammatory response in the supporting tissues^[7], and any factor influencing bone remodeling will affect the rate of tooth movement^[8].

Extended orthodontic treatment presents significant challenges, including patient dissatisfaction, pain, discomfort, caries, white spot lesions, gingival recession, compromised oral hygiene, and root resorption^[9,10].

Numerous studies aim to accelerate tooth movement by influencing bone metabolism or modifying orthodontic techniques and devices. These approaches include mechanical methods, such as reducing friction with improved archwires and self-ligating brackets^[11,12]; pharmacological/chemical methods, such as the use of substances like prostaglandins, vitamin D3, interleukins, parathyroid hormone, and thyroxine, while avoiding anti-inflammatory drugs that inhibit bone formation^[13–18]; physical induction methods, including vibration forces, ultrasound, electrical currents, and electromagnetic fields^[19–22]; and surgical methods, including corticotomy, piezocision, alveolar distraction osteogenesis, and periodontally accelerated osteogenic orthodontics, are clinically proven and effective, especially for adults^[2].

Platelet-rich plasma (PRP), initially defined in hematology as plasma with a higher platelet concentration than peripheral blood^[23,24], gained prominence after its application in oral and maxillofacial surgery for tissue regeneration^[25,26]. PRP, containing over 30 growth factors including Platelet-derived growth factor (PDGF), Epidermal growth factor (EGF), Transforming growth factor beta (TGF-β), Fibroblast growth factor (FGF), Insulin-Like Growth Factor (IGF), Vascular Endothelial Growth Factor (VEGF), and Concentrated Growth Factor (CGF), promotes bone and soft tissue healing^[25]. Platelet-rich fibrin (PRF), a second-generation platelet concentrate developed by Choukroun, offers a simpler and safer preparation method, avoiding anticoagulants and bovine thrombin^[26].

This study aims to evaluate the effectiveness of PRF in accelerating canine retraction following its application in the alveolar socket after upper first premolar extraction.

The investigators hypothesize that PRF application to the socket of an extracted first premolar will accelerate canine movement.

The study aims specifically to:

1. Evaluate the acceleration rate of canine retraction after PRF application to the first premolar socket, taking advantage of extraction without raising surgical flaps.

2. Evaluate postoperative pain by assessing the modulation of inflammation through sustained cytokine release.

Materials and methods

To address the research purpose, the investigators designed and implemented a split-mouth and randomized double-blind clinical trial in accordance with the Declaration of Helsinki and with the Consolidated Standard of Reporting Trials statement writing guidelines for clinical trials (Fig. 1)^[27].

Figure 1.

CONSORT 2010 flow diagram. CONSORT, Consolidated Standard of Reporting Trials.

Ethical approval was obtained from the Scientific Research Board (approval no. 236, 15 January 2023).

This study is registered in the Research Registry under the identification number: research registry 11094, with the following reference link: https://www.researchregistry.com/browse-the-registry#home/.

HIGHLIGHTS

• Platelet-Rich Fibrin (PRF) Speeds Up Canine Retraction: PRF application in extraction sockets significantly increased the rate of maxillary canine movement in the first 2 months (P < 0.001), though no difference was seen by the third month.

• PRF Lowers Early Post-Op Pain: Pain levels were significantly reduced on the PRF-treated side at 1 and 3 days post-application (P < 0.01), but matched the control side by day 7.

• PRF May Help Preserve Anchorage: The PRF side showed slower molar movement (anchorage loss) throughout the study, suggesting a possible stabilizing effect, though results were not statistically significant.

This article is compliant with the TITAN Guidelines 2025 – governing declaration and use of AI^[28].

Participants

Patient records from the Department of Orthodontics were reviewed, and individuals aged 13–23 years with an initial diagnosis of Class II malocclusion or dental protrusion were contacted for participation. Additionally, patients referred to the department for further treatment were followed up to contribute to the sample.

Eligible participants were thoroughly informed about the study, including a detailed explanation of the treatment approach. All questions were addressed, and written consent was obtained through a signed informed consent form.

The final sample comprised 20 patients. PRF was applied in the alveolar socket following the extraction of the upper first premolar on one side, while the contralateral side served as the control, with no additional material applied during retraction.

Sample selection criteria

Inclusion criteria

Patients were selected from those referred to the orthodontic department based on the following inclusion criteria:

1. Individuals with permanent dentition, aged between 12 and 23 years.

2. Patients presenting with dental protrusion and a treatment plan requiring the extraction of the upper first premolars.

3. Confirmed skeletal Class II relationship, verified by ANB angle (>4°), based on cephalometric radiographs.

4. Good general and oral health.

5. No use of pain-altering medications for at least 1 week prior to the start of treatment.

Exclusion criteria

Patients who had previously undergone orthodontic treatment.

Variables

The primary predictor variable was mainly the treatment protocol in the study corresponding to either filling the socket with PRF (study side) or leaving the socket without adding any substance (control side).

Primary outcome variables include:

1. Rate of canine retraction

2. Rate of anchorage loss

Secondary outcome variables include:

Assessment of the levels of pain and discomfort associated with the application of PRF.

Blinding and randomization

Randomization was performed using a computer-generated random allocation sequence created by an independent researcher not involved in the clinical procedures or outcome assessment. Allocation was concealed using opaque, sequentially numbered, sealed envelopes. Each envelope indicated the intervention side (right or left) for PRF application and was opened only at the time of extraction by a third-party assistant.

To ensure double blinding, the patients were unaware of which side received the PRF, and the outcome assessor (responsible for model measurements and data analysis) was blinded to group allocation. The orthodontist performing the extractions and PRF application did not participate in outcome measurement or statistical analysis.

Research protocol

• Separation elastics were placed around the upper first molars for 4 days using products from American Orthodontics®.

Appropriate brackets (MBT – 0.022) from the same manufacturer were selected.

• Upper dental impressions were taken using hydrogum alginate and sent to the laboratory for the fabrication of a 0.9 mm stainless steel archwire. The brackets were welded to the archwire, and a Trans-Palatal Arch was secured using Promedica Glass Ionomer Cement®.

• MBT 0.022 brackets from American Orthodontics were bonded using light-cured composite. Arch wire sequencing was then performed using American Orthodontics wires in the following order: 0.014-inch NITI, 0.016-inch NITI, 0.016-0.022 inch NITI, 0.017-0.022- inch NITI, 0.019-0.025 inch NITI, and finally, a 0.019-0.025 inch stainless steel wire, which served as the base wire. Ligature ties from American Orthodontics® were used to secure the wires within the brackets.

Second stage treatment procedures (surgical intervention)

PRF preparation protocol

1. Blood Collection:

• 10 mL of venous blood was drawn from the cephalic vein using a 21-gauge needle and collected into sterile glass-coated plastic tubes (no anticoagulant).

2. Centrifugation:

• Immediate centrifugation at 3,000 rpm (400 × g) for 10 minutes (HWLAB Centrifuge) at room temperature.

• This protocol yields a fibrin clot sandwiched between:

Upper layer: Acellular plasma.

Lower layer: Red blood cell residue.

3. PRF Clot Extraction:

• The fibrin clot (mean volume: 0.5–1.0 mL per tube) was carefully separated from the RBC layer using sterile tweezers.

Excess fluid was gently pressed out with sterile gauze to form a condensed PRF membrane.

4. Socket Application:

• The PRF clot was placed into the extraction socket immediately post-extraction, filling the alveolar space completely.

Primary closure was achieved with 4-0 non-resorbable silk sutures.

Rationale for protocol

• 3000 rpm/10 min: Optimizes growth factor retention (e.g., PDGF, TGF-β) while avoiding excessive leukocyte inclusion, which could exacerbate inflammation.

Glass-coated tubes: Enhance fibrin polymerization vs. plain plastic tubes.

• Prior to extraction, the patient was instructed to rinse with a 0.012% chlorhexidine mouthwash (Afamia Hex-f®) for 1 minute. The surrounding mucosal area was cleaned with chlorhexidine-soaked gauze. Local anesthesia was administered via infiltration using a 27-gauge needle and lidocaine 2% with epinephrine 1:90 000 (Newcaina, New Stetic, Colombia®) (Fig. 2).

• The upper first premolar was extracted on both sides following local anesthesia, ensuring minimal discomfort. The periodontal ligament was severed using straight separating pliers to disconnect the ligament between the gingival margin and the tooth circumference. The periodontal fibers around the cervical area of the tooth were also carefully cut. Extraction was performed using forceps number 7, specifically designed for premolar extractions (Figs. 3–7).

Figure 4.

After extraction of both premolars.

Figure 5.

Platelet-rich fibrin preparation.

Figure 6.

Placement of platelet-rich fibrin within the alveolar socket.

Figure 2.

Local anesthesia before upper first premolar extraction.

Figure 3.

Extraction of the upper first premolar.

Figure 7.

Suturing procedure (researcher’s own image).

Third stage treatment procedures (upper canine retraction)

After first premolar extraction and PRF application in one side, maxillary canine retraction was initiated using closed-coil nickel-titanium springs (Jiscop). These springs extended from the canine bracket to a hook on the first maxillary molar, applying approximately 150 g of force to both experimental and control sides. Force magnitude was verified and maintained at 150 g using an intraoral spring (Dentaurum, Ispringen). Retraction continued until a Class I canine relationship was achieved on one side (Fig. 8).

Figure 8.

Canine retraction until a Class I canine relationship was achieved on one side.

Orthodontic monitoring during upper canine retraction

Follow-up was done monthly, with adjustments made every 2 weeks. At each orthodontic follow-up appointment, the force generated by the spring was checked using the intraoral spring and adjusted to be 150 g (replacing with a shorter spring if needed).

Monitoring continued until achieving a Class I canine relationship as shown in Figure 9.

Figure 9.

Achieving a Class I canine relationship.

Analysis of gypsum models

Upper impression taking times and study of gypsum models:

Impressions were taken using rubber material from ZETAPLUS®. To prevent distortion during impression removal, the brackets were covered with a thin layer of red utility wax without approaching areas used in gypsum model analysis. The impressions were then poured using enhanced orthodontic gypsum at the following times:

• T0: Before starting upper canine retraction

• T1: 1 month after upper canine retraction

• T2: 2 months after upper canine retraction

• T3: 3 months after upper canine retraction

Reference points and planes

The following reference points and planes were adopted using the Ziegler method (Ziegler & Ingervall, 1989)^[29] (Fig. 10):

• Midpalatal suture: Defined using the points of the incisive papilla and the posterior palatal rugae. This served as the reference plane against which variables were measured.

• Mesial end of the third palatal rugae: This stable reference point was used to analyze the mesiodistal movement of canines and molars^[30].

• The central pit of the first permanent molar.

• The cusp tip of the maxillary canine.

Figure 10.

Points and reference levels used to study variables:.

1. The vertical distance between the cusp apex of the right upper canine and the medial end of the right third palatal ruga.2. The vertical distance between the cusp apex of the left upper canine and the medial end of the left third palatal ruga.3. The vertical distance between the central fossa of the right upper first molar and the medial end of the right third palatal ruga.4. The vertical distance between the central fossa of the left upper first molar and the medial end of the left third palatal ruga.

Patient discomfort assessment

To assess pain and discomfort levels associated with the application of PRF within the alveolus, a questionnaire was used. Patients self-administered the questionnaires on the treatment chair.

Questionnaire administration times

P1: 24 hours post-operation

P2: 3 days post-operation

P3: 7 days post-operation

All questions were answered using a Visual Analog Scale (VAS). VAS is an 11-point scale where patients select the point that best represents their current state. For example, 0 represents no pain, and 10 represents the worst possible pain (Fig. 11).

Figure 11.

Visual Analog Scale.

Statistical analysis

All statistical analysis was done using IBM SPSS 2020 version 27.0 software for Windows.

Paired samples t-test was used for analyzing results to show differences between the study side and the control side. A P-value less than 0.05 was typically considered to be statistically significant.

The SPSS program was used to analyze the research results. The distribution of the control and experimental groups was hidden from the researcher during the statistical analysis phase to ensure blinding of the statistician and avoid detection bias.

Results

The final sample consisted of 40 canine retraction procedures performed on 20 patients (14 female, 6 male, aged 18 ± 5.3 years). Each patient underwent retraction of a maxillary canine on one side using PRF within the alveolus (experimental group), and on the contralateral side using a traditional retraction technique (control group). This resulted in two equal-sized groups based on the retraction method.

The patients in the research sample were distributed according to gender (Table 1).

Table 1.

Distribution of patients in the study sample according to gender

Characteristic	Value
Gender, n (%)
Male	6 (30%)
Female	14 (70%)
Mean age ± SD (years)	18.0 ± 5.3
Age range (years)	12–23
Diagnosis
Class II division 1	20 (100%)
Skeletal pattern
Confirmed by ANB angle >4°	20 (100%)
Tooth extraction plan	Bilateral upper first premolars
Oral health status	All patients had healthy periodontium and no active caries.

The ANB angle evaluates the anteroposterior relationship between the maxilla and mandible

Error of the method

Student’s t-test for paired samples was conducted at a 95% confidence level to calculate the measurement error for the variables included in the study using gypsum models. The results of this test showed that the P-value for all variables was greater than 0.05, indicating no significant differences between the two measurements. This confirms the absence of systematic errors and suggests that a single measurement reading is reliable. The test results are presented in Table 2.

Table 2.

Results of statistical significance tests to study differences in the mean measurements of gypsum models for the purpose of evaluating systematic errors

Variable studied	Number of cases	Mean of first measurement	Standard deviation of first measurement	Mean of second measurement	Standard deviation of second measurement	Differences between measurements
						Mean difference	Standard deviation of differences	Lower limit	Upper limit	Calculated t-value	P-value	Significance of differences
C.Dist.E	10	6.64	4.04	6.63	4.03	0.007	0.365	0.163	0.178	0.092	0.928	N.S
C.Dist.C	10	7.53	3.18	7.51	3.37	0.020	0.490	0.209	0.250	0.187	0.854	N.S
M.Dist.E	10	14.18	2.70	14.18	2.73	0.004	0.133	0.058	0.067	0.150	0.882	N.S
M.Dist.C	10	13.36	1.94	13.35	1.95	0.010	0.122	0.047	0.067	0.367	0.718	N.S

Test used: paired t-test (Student’s t-test for paired samples).

(N.S): no statistically significant differences.

(*): Significant at P < 0.05.

(**): Significant at P < 0.01.

(***): Significant at P < 0.001.

C.Dist.E: the vertical distance between the tip of the upper canine and the medial end of the third palatal rugae (experimental side) (mm).

C.Dist.C: the vertical distance between the tip of the upper canine and the medial end of the third palatal rugae (control side) (mm).

M.Dist.E: the vertical distance between the central fossa of the upper first molar and the medial end of the third palatal rugae (experimental side) (mm).

M.Dist.C: the vertical distance between the central fossa of the upper first molar and the medial end of the third palatal rugae (control side) (mm).

Study of the effect of PRF application on the speed of upper canine retraction and anchorage loss

• Tables 3 and 4 present the results of the Paired t-test (Student’s t-test for paired samples) to examine the significance of differences between the side where PRF was applied and the side where traditional retraction was performed across the three evaluation periods for the following variables:

1. Speed of upper canine retraction (mm/month)

2. Speed of mesial movement of the upper first molar (anchorage loss) (mm/month).

• Table 3 indicates a statistically significant difference between the control side and the study side where PRF was applied regarding the speed of upper canine retraction during the first and second months, as the P-value was less than 0.05 for both time periods.

• However, no significant difference was observed between the two sides in the third month. By analyzing the algebraic sign of the differences between the means, it can be concluded that the speed of upper canine retraction was greater on the side where PRF was applied compared to the control side.

• Regarding the mesial movement of the upper first molar (anchorage loss), the loss of anchorage on the side where PRF was applied was slower compared to the control side across all evaluation periods, but without significant differences. The P-value was greater than 0.05 at a 95% confidence level (Table 4).

Table 5.

Results of the paired samples t-test comparing the mean pain scores between the study group and the control group after 24 hours

Calculated t-value	Mean difference	P-value	Confidence level	Significance of differences
3.0666	1.2	0.0066	95%	Significant differences exist

Table 6.

Results of the paired samples t-test comparing the mean pain scores between the study group and the control group on the third day

Calculated t-value	Mean difference	P-value	Confidence level	Significance of differences
3.1830	1.2	0.0052	95%	Significant differences exist

Table 3.

Results of statistical significance tests for differences in (upper canine retraction speed) between the experimental side and the control side in the study sample

		Study group			Control group			Mean difference
Time period	Variable	Number of cases	Mean	Standard deviation	Number of cases	Mean	Standard deviation	Mean difference	Standard deviation	Lower limit	Upper limit	Calculated t-value	P-value
T0–T1	C.RetS	20	1.62	0.51	20	0.65	0.22	0.96	0.15	0.62	1.31	6.29	0.0001
T1–T2	C.RetS	20	1.94	0.63	20	1.09	0.29	0.86	1.18	0.45	1.27	4.75	0.0010
T2–T3	C.RetS	20	1.29	0.30	20	1.25	0.23	0.03	0.073	0.19	0.13	0.47	0.65

Test used: paired t-test (Student’s t-test for paired samples).

(N.S): no statistically significant differences.

(*): Significant at P < 0.05.

(**): Significant at P < 0.01.

(***): Significant at P < 0.001.

Table 4.

Results of statistical significance tests for differences in (medial movement speed of the upper first molar) between the experimental side and the control side in the study sample

		Study group			Control group			Mean differences
Time period	Variable	Number of cases	Mean	Standard deviation	Number of cases	Mean	Standard deviation	Mean difference	Standard deviation	Lower limit	Upper limit	Calculated t-value	P-value
T0–T1	M.Ret.E	20	0.24	0.12	20	0.16	0.07	0.08	0.05	−0.13	0.28	1.69	0.12
T1–T2	M.Ret.E	20	0.12	0.09	20	0.25	0.24	0.13	0.07	−0.07	0.66	1.78	0.11
T2–T3	M.Ret.E	20	0.45	0.17	20	0.48	0.19	0.03	0.06	−0.34	0.38	0.52	0.61

Evaluation of patient discomfort levels

The pain index was studied in patients from both the control and experimental groups 1 day after extraction, 3 days after extraction, and 1 week after extraction.

Paired samples t-tests (Tables 5 and 6) revealed statistically significant differences (P < 0.05) in mean pain scores between groups on days 1 and 3 while no significant difference (P > 0.05) was found on day 7 (Table 7).

Table 7.

Results of the paired samples t-test comparing the mean pain scores between the study group and the control group on the seventh day

Calculated t-value	Mean difference	P-value	Confidence level	Significance of differences
0.3612	0.1	0.722	95%	No significant differences

Discussion

• This randomized controlled clinical trial involved Class II Division 1 malocclusion patients requiring upper first premolar extractions, a common treatment for excessive maxillary anterior protrusion. Although retracting the upper canines after extraction of the first premolars is a common orthodontic procedure, it is considered slow and demanding on anchorage requirements, typically taking 6–8 months^[31].

• The average age of the sample participants was 18 years. Only adult patients were included in this study to exclude the factor of growth and metabolic changes occurring in the alveolar bone of young patients before puberty, which could act as a confounding factor when studying the rate of tooth movement^[32].

The results of this study demonstrated that the speed of upper canine retraction on the side where PRF was applied was significantly greater compared to the control side during the first and second months (P < 0.05). The differences between the two sides during the first and second months were 0.545 mm and 0.598 mm, respectively. The acceleration observed in the first 2 months of upper canine retraction can be explained by the fact that PRF application facilitated the retraction process, making it faster than traditional retraction within the same time frame. While the acceleration of canine retraction during the first 2 months was statistically significant, the clinical relevance of this reduction depends on the total treatment duration. Assuming an average retraction period of 6–8 months, a 1.1 mm acceleration in the initial phase may reduce overall treatment time by approximately 15–20%. However, further studies with longer follow-up periods are needed to confirm this potential benefit.

This may be attributed to the role played by the diverse mixture of growth factors, cytokines, and enzymes present in the L-PRF clot^[33].

These components exhibit anti-inflammatory effects, enhancing tissue healing capacity, while certain cytokines, such as tumor necrosis factors, may exacerbate the inflammatory response and accelerate tooth movement^[34]. Additionally, L-PRF can modulate both inflammatory and anti-inflammatory responses, with its precise effects likely dependent on the timing of release, concentration, and the content of growth factors^[35].

This study found no significant differences between the two sides in either group regarding the speed of upper canine retraction during the third month, with a difference of 0.041 mm (P = 0.658).

Our results align with those of El-Timamy et al ^[36], and Tehranchi et al ^[37]. These studies also found that the speed of canine retraction in the first and second months was greater than in the control group. However, our protocol differed in that we used L-PRF clots placed in the extraction socket, whereas they utilized PRP and injectable PRF (I-PRF).

Our findings differ from those of Chandak and Patil^[38], which may be attributed to differences in the protocol for PRF preparation, application methods, and the specific dental segment being retracted. While Chandak retracted the entire anterior dental segment, our study focused solely on the retraction of the upper canines.

The results of this study showed that the speed of mesial movement of the upper first molars (anchorage loss) on the study side was slower compared to the control side at all evaluation times, but without significant differences (P > 0.05). This result can be explained by the fact that the alveolar bone’s reaction to PRF application was localized to the application site and did not extend to the posterior segment. The applied force led to faster retraction of the upper canine within the alveolar bone, and thus its effect on the first molars was reduced, resulting in slower anchorage loss compared to traditional retraction.

Patient responses were recorded 24 hours after the extraction and PRF application (T1). They were not recorded immediately after the procedure to avoid the influence of pain relief from the local anesthesia used during the surgical procedure on the study results. Patients were instructed not to take painkillers unless absolutely necessary and to inform us if they did, in order to record accurate pain and discomfort scores.

The results of the paired samples t-test showed statistically significant differences (P = 0.0066 and P = 0.0052) at a 95% confidence level in the mean pain scores between the study group and the control group in our sample on the first and third days, respectively, after the application of PRF for the purpose of accelerating orthodontic treatment.

After reviewing the literature, we found several studies that investigated pain and discomfort levels following the application of PRF. Our study’s results agreed with those of Bilginaylar et al ^[39], Kumar et al ^[40], and Muñoz et al ^[41], who found that the application of PRF reduced pain levels in patients.

Our results also aligned with those of Phan et al ^[42] and Zhu et al ^[43], who found that the use of PRF could reduce pain levels after the surgical extraction of third molars.

The role of PRF in pain reduction and healing enhancement can be attributed to Choukroun et al^[44]:

• The slow release of growth factors (over 7–11 days).

• The stable fibrin matrix.

• Hemostasis.

This can also be attributed to the high concentration of white blood cells in PRF, which gives it an immune-supportive effect. Additionally, PRF plays an important role in regulating the inflammatory process. Therefore, the use of PRF reduces pain and postoperative swelling and may decrease the occurrence of infections when applied^[45].

Our results differed from Rutkowski et al regarding the significance of pain levels, as they did not find a statistically significant difference in pain after the application of PRP in third molar extraction sockets. They attributed this to the fact that postoperative painkillers may have prevented patients from reporting clear pain complaints^[46].

The advantages of this study include the use of a split-mouth design, which allowed patients to act as their own controls, enhancing the reliability of the results. To further ensure accuracy, both the patients and the investigator conducting the measurements were blinded, effectively minimizing researcher bias.

Unlike surgical techniques like corticotomy or piezocision, PRF application is minimally invasive, requiring no flap elevation, bone cutting, or extensive tissue manipulation. It simply involves standard tooth extraction followed by PRF placement in the socket, thus minimizing trauma and postoperative complications.

The application of PRF within the extraction socket accelerated the retraction of the upper canines compared to traditional methods, though this effect was observed only during the first 2 months.

On the side where PRF was applied, the mesial movement (anchorage loss) of the upper first molars was slower compared to the traditional retraction side, although the difference was not statistically significant.

Additionally, the use of PRF in the extraction socket during upper canine retraction for acceleration purposes resulted in a significant reduction in pain levels.

The limitations of this article include the lack of detailed analysis regarding the pattern of orthodontic movement of the upper canine (whether bodily or tipping) following accelerated retraction using PRF application. Additionally, the study did not explore the potential influence of gender on the acceleration process.

This study did not differentiate between tipping (crown-dominated movement) and bodily movement (parallel root displacement), which have distinct biological and clinical implications. Tipping may yield faster initial movement but risks root resorption and unstable occlusion, whereas bodily movement is slower but biomechanically ideal for long-term stability. Future studies should use cone-beam CT to quantify root displacement patterns with and without PRF, and compare force systems (e.g., low-friction mechanics vs. conventional sliding) to isolate PRF’s effect on movement type.

Our sample (n = 20) lacked the power to assess gender- or age-specific responses. Gender differences may exist because estrogen levels in females may modulate bone remodeling. Furthermore, adolescents (<18 years) typically exhibit faster tooth movement than adults. Therefore, future studies should stratify recruitment by gender and age (e.g., 12–17 vs. 18–30 years) using larger samples (n ≥ 30/group), and correlate biomarkers (e.g., serum estrogen, IGF-1) with retraction velocity.

Conclusions

This randomized controlled trial found that PRF significantly accelerated maxillary canine retraction during the first 2 months post-extraction and reduced postoperative pain in the early days, improving patient comfort. Although the anchorage loss was slightly reduced, the difference was not significant. PRF appears to be a minimally invasive, biologically active adjunct that may enhance the efficiency and experience of orthodontic treatment. Further research is needed to confirm its long-term benefits and refine its clinical application.

Ethical approval

Ethical approval was obtained from the Scientific Research Board Resolution of a university in Latakia, Syria.

Consent

Written informed consent was obtained from the patients for publication of this study and accompanying images, a copy of the written consent is available for review by the Editor-in-Chief of Annals of Medicine and Surgery.

Sources of funding

The study had no external sources of funding and therefore was in no way influenced by any sponsorship.

Author contributions

A.A.: first author, methodology, data analysis and interpretation. N.S.: writing the paper, data interpretation.

Conflicts of interest disclosure

The author declares that there is no conflict of interest.

Guarantor

Dr. Nadim Sleman.

Research registration unique identifying number (UIN)

This study is registered in the Research Registry under the identification number: research registry 11094, with the following reference link: https://www.researchregistry.com/browsethe-registry#home/.

Provenance and peer review

Not commissioned, externally peer-reviewed.

Data availability statement

All data are available upon request.