|Year : 2023 | Volume
| Issue : 5 | Page : 454-462
Evaluation of root biomodification as an adjunct to platelet-rich fibrin versus amniotic membrane and coronally advanced flap in class I and class II gingival recession defects: A randomized controlled study
Rodda A Kumar, Rekha R Koduganti
Department of Periodontics, Panineeya Mahavidhyalaya Institute of Dental Sciences & Research Centre, Dilsukhnagar, Hyderabad, India
|Date of Submission||27-Mar-2023|
|Date of Decision||22-Jul-2023|
|Date of Acceptance||26-Jul-2023|
|Date of Web Publication||30-Oct-2023|
Dr. Rekha R Koduganti
Department of Periodontics, Panineeya Mahavidyalaya Institute of Dental Sciences, Road no. 5, Kamalanagar, Dilsukhnagar, Hyderabad 500060
Source of Support: None, Conflict of Interest: None
Aim: This study aimed to compare the effects of root bio modification only with coronally advanced flap (CAF; control group) versus placement of either platelet-rich fibrin (PRF) or amniotic membrane (AM) after root biomodification (test groups) using the CAF technique in class I or class II gingival recession defects. Hence, this study evaluated the role of root biomodification alone and as an adjunct with PRF or AM membrane in class I and class II gingival recessions. Materials and Methods: This was a randomized, parallel-arm, clinical trial conducted on 24 patients. Subjects were equally divided into three groups. Patients in group 3 (control group) were treated with CAF alone and hyaluronic acid (HA) root conditioning and those in group 2 underwent CAF with AM and HA root conditioning whereas those in group 1 underwent CAF with PRF and HA root conditioning for class I or class II gingival recessions. The clinical variables were assessed pre and 3 months and 6 months postsurgery. The visual analog scale (VAS) was assessed on the 10th and 30th day, postsurgery. Intragroup analysis was done by repeated one-way analysis of variance test followed by Bonferoni’s multiple comparisons test. Intergroup comparison used repeated two-way analysis of variance test for continuous data. All P value less than 0.05 were considered statistically significant. Results: A comparison within the groups yielded insignificant results in group 3 (control group), whereas in group 1 (PRF + HA root conditioning) the probing depth (PD) and percentage root coverage (PRC) values did not improve significantly and in group 2 (AM + HA root conditioning) the PRC values did not show significant improvement. Between the groups, however, it was observed that the test groups 1 and 2 performed better than the control group related to all the clinical parameters and the VAS scores reflected superior results in group 2. Conclusion: CAF was effective as a treatment modality. The test group yielded a better percentage of root coverage than the control group, though statistically insignificant.
Keywords: Amnion, Gingival Recession, Hyaluronic Acid, Platelet-Rich Fibrin Membrane, Surgical Flap
|How to cite this article:|
Kumar RA, Koduganti RR. Evaluation of root biomodification as an adjunct to platelet-rich fibrin versus amniotic membrane and coronally advanced flap in class I and class II gingival recession defects: A randomized controlled study. J Int Oral Health 2023;15:454-62
|How to cite this URL:|
Kumar RA, Koduganti RR. Evaluation of root biomodification as an adjunct to platelet-rich fibrin versus amniotic membrane and coronally advanced flap in class I and class II gingival recession defects: A randomized controlled study. J Int Oral Health [serial online] 2023 [cited 2023 Dec 2];15:454-62. Available from: https://www.jioh.org/text.asp?2023/15/5/454/388792
| Introduction|| |
Gingival recession is a very common problem clinically witnessed and is caused by excessive or inadequate tooth brushing, destructive periodontal disease, tooth malposition, alveolar bone dehiscence, high muscle attachment, frenum pull, and occlusal trauma, The prognosis for class I and class II recessions is good provided there is no trauma from occlusion or malpositioning of the involved tooth. Free gingival grafts, connective tissue grafts, pedicle graft are few of the many procedures available to treat receded gingivae. The best technique to date for multiple recession defects is coronally advanced flap (CAF) with good evidence of success.,
Though many regenerative membranes have been researched, using CAF technique, a comparative assessment between amniotic membrane (AM) and platelet-rich fibrin (PRF) with adjunctive role of root conditioning has not been studied recently. However, with the focus now shifting to the beneficial role of injectable PRF, lasers, and hyaluronic acid (HA), in root conditioning, researchers have once again included root conditioning in their surgical protocol. Biomodification of the root surface has been suggested by some researchers before the surgical procedure to enhance the surgical outcome by removing the smear layer and endotoxins and promoting a firm fibrin linkage onto the root surface., A 0.2% of HA was used in this study for root biomodification as it is a potent anti-inflammatory agent and modulates wound healing due to its ability to scavenge the inflammatory cell-derived reactive oxygen species. Platelet concentrates have a very important role to play in periodontal regeneration and platelet-rich fibrin has been observed to be the best among them due to its extended release of growth factors and optimal tissue healing properties., Human AM is the inner layer of the placenta and is comprised of avascular connective tissue and a basement membrane-rich in collagen III, IV, and V. The most important feature is it lacks antigenicity and has potent antibacterial and anti-inflammatory properties.
Root biomodification before recession coverage had been employed previously with limited success; however, with the advent of materials like injectable PRF, HA, and lasers, the interest in this procedure was renewed.
| Materials and Methods|| |
The institutional ethical committee approved this study which was conducted from November 2020 to July 2021 (PMVIDS & RC/IEC/PERIO/DN/0287-19). The ethical standards established by the World Medical Association (WMA) in the Declaration of Helsinki 1964 were adhered to and all the participants were given a detailed verbal and written description of the study, and a signed consent form was obtained [Figure 1]. This study was also registered CTRI/2020/10/028753.
Patients with either single or multiple Miller’s class I and II recession defects with probing depth (PD) > 3 mm, clinical attachment level (CAL) > 5 mm, and keratinised tissue width > 2 mm were included in the study. Pregnant and lactating women, smokers, systemically compromised patients, subjects who had undergone periodontal therapy within the last six months, and those who were on antibiotics three months prior which was confirmed while recording the case history, were excluded.
Sample size calculation
To get a difference in complete root coverage (CRC) between the groups with power at 90% and 95% confidence interval, eight patients had to be included in each group. The primary outcome variables assessed were the recession depth (RD), recession width (RW), and percentage root coverage (PRC), whereas PD, CAL, and visual analog scale (VAS) were the secondary outcomes measured.
Estimation of clinical parameters
A standard periodontal probe (UNC-15) was used to measure the PD, CRC, recession depth (RD), gingival recession width (RW) which were assessed pre and 3 months (D3) and 6 months (D6) postsurgery. The VAS was assessed on the 10th and 30th day of postsurgery. VAS was recorded for each patient on the 10th and 30th day.
One investigator KRR allotted the cases by randomly picking them up from sealed envelopes and investigator AK performed the surgeries in all the groups. Both the patient and statistician were blinded to the investigation.
Group 3 included eight patients wherein after HA gel application for root conditioning, the gingiva was treated using CAF only (control group). Group 2 included eight patients wherein after HA gel application as a root conditioner, the gingiva was treated using CAF with AM. Group 1 included eight patients wherein HA gel was used as a root conditioner and PRF was used with CAF to augment the gingiva (test groups).
The patients were motivated related to oral hygiene maintenance. Scaling, root planning, and occlusal adjustments were done. Random allocation of the patients into three groups (group 1, group 2, and group 3) was followed.
On completion of the baseline examination and thorough initial therapy, the patient was instructed to rinse the mouth with 1:1 ratio of 0.2% chlorhexidine digluconate solution (Hexidine Mouthwash, ICPA Health Products Ltd). The operative site was anesthetized with 2% lignocaine HCL (Lignox, Indoco Remedies Ltd) with adrenaline (1:80,000) using block and infiltration techniques.
PRF membrane preparation
PRF was harvested from a blood sample (10 mL) drawn from the patient’s antecubital vein at the time of surgical procedure. It was then treated with a single centrifugation using Remi C-852 4 × 15 mL laboratory centrifuge at 2700 rpm for 12 min. At the end of centrifugation procedure, three distinct layers were formed of which the intermediate layer was that of a dense platelet-rich fibrin clot [Figure 2]. The fibrin clot was easily separated from the red blood cell (RBC) base (preserving a small RBC layer) using sterile tweezers and scissors. This dense platelet-rich fibrin clot was used as a membrane.
After local anesthesia, a trapezoidal flap was raised using disposable ophthalmic blade (SRS Micro Edge Side Port, SRS Enterprise, India). Initially, a submarginal incision was made on the buccal aspect of the involved tooth, both mesially and distally at the level of the tooth’s cementoenamel junction. The horizontal incisions were connected to divergent vertical releasing incisions made along the line angles of the involved teeth. Trapezoidal split-thickness flap was elevated by sharp dissection which was then followed by full-thickness flap reflection by periosteal elevator up to mucogingival junction, such that the flap could be passively positioned coronally over the defect, without tension. The papillae adjacent to the recession area, including the facial portion of the gingival tissue that remained attached to the adjacent teeth, was de-epithelialized to create a bleeding connective tissue bed. After flap elevation, the exposed root surface was gently planed with sharp curettes, followed by root conditioning using HA (Gengigel 0.2%, RICERFARMAS.R.L.Via Egadi, 720144 Milano, Italy) to maintain the attached connective tissue and the prepared PRF membrane was placed and sutured using NW2670 Ethicon 6.0 Vicryl Surgical suture (Johnson & Johnson Pvt Ltd). The pedicle flap was positioned coronal to the cementoenamel junction of the recipient’s tooth and sutured by 6-0 absorbable sutures. The area was protected with periodontal dressing [[Figure 3]A–D].
|Figure 3: (A) Measurement of RD at baseline in group 1. (B) Application of HA after flap reflection. (C) Application of PRF. (D) Measurement of RD after 6 months|
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The same surgical procedure as group 1 was employed in group 2. But in group 2 instead of PRF, AM was the regenerative material used [[Figure 4]A–D].
|Figure 4: (A) Measurement of RD at baseline in group 2. (B) Application of HA after flap reflection. (C) Application of AM. (D) Measurement of RD after 6 months|
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In this group, the same surgical procedure (i.e., only CAF) was performed. After flap reflection and root conditioning with HA (Gengigel 0.2%), the flap was positioned coronal to the cementoenamel junction of the recipient’s tooth and sutured by 6-0 absorbable sutures. The area was protected with periodontal dressing [[Figure 5]A–C].
|Figure 5: (A) Measurement of RD at baseline in group 3. (B) Application of HA after flap reflection. (C) Measurement of RD after 6 months|
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The patients were prescribed analgesics (Aceclofenac 100 mg + Serratiopeptidase 15 mg; Zerodol S Ipca Laboratories Ltd) thrice a day for 5 days and antibiotics (Amoxicillin—Mox 500 mg, Sun Pharmaceutical Industries Ltd) thrice a day for 5 days postsurgery. They were also asked to use Hexidine mouthwash (0.2%) twice a day for 1 month. Each patient was reinstructed for proper oral hygiene measures and was re-evaluated, after 1 week and thereafter monthly, for a 6-month period, wherein scaling and root planning was performed, throughout the mouth other than the operated site at each visit. All the patients reported for follow-up and no adverse effects to the procedure or drug were reported.
This study made use of the software SPSS 23.0 version, IBM Company USA. To get a difference in CRC between the groups with power at 90% and 95% confidence intervals, eight patients had to be included in each group. Intragroup analysis was done by repeated one-way analysis of variance test followed by Bonferoni’s multiple comparisons test. Intergroup comparison used repeated two-way analysis of variance test for continuous data. All P value less than 0.05 were considered statistically significant.
| Results|| |
The RD values decreased significantly from D0, D3 to D6 (P = 0.003). The RW values also decreased significantly from D0, D3 to D6 (P = 0.006). The PD values decreased but were not significant from D0, D3 to D6 (P = 0.024). The CAL values decreased significantly from D0, D3 to D6 (P = 0.003). There were no significant changes in PRC values from D3 to D6 (P = 0.282). Therefore, there was a significant decrease from D0, D3 to D6 for all the clinical parameters in group 1, except the PD and PRC values which were not statistically significant [Table 1].
|Table 1: Intragroup estimation of clinical parameters at different points of time in group 1 (CAF + PRF) using repeated one-way analysis of variance and Bonferoni’s test|
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The RD values decreased significantly from D0, D3 to D6 (P = 0.019). The RW values also decreased significantly from D0, D3 to D6 (P = 0.020). The PD values decreased significantly from D0, D3 to D6 (P = 0.009). The CAL values decreased significantly from D0, D3 to D6 (P = 0.002). There were no significant changes in PRC values from D3 to D6 (P = 0.070). Therefore, there was a significant decrease from D0, D3 to D6 for all the clinical parameters in group II, except the PRC values which were not statistically significant [Table 2].
|Table 2: Intragroup estimation of clinical parameters at different points of time in group 2 (CAF + AM) using repeated one-way analysis of variance and Bonferoni’s test|
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The RD values did not improve significantly from D0, D3 to D6 (P = 0.125). The RW values also did not show improvement from D0, D3 to D6 (P = 0.078). The PD values showed no significant improvement from D3 to D6 (P = 0.051). The CAL values also did not improve D0, D3 to D6 (P = 0.125). There was no significant change in PRC values from D3 to D6 (P = 0.083). Therefore, there was no significant change from D0, D3 to D6 for all the clinical parameters [Table 3].
|Table 3: Intragroup estimation of clinical parameters at different points of time in group 3 (CAF) using repeated one-way analysis of variance and Bonferoni’s test|
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Intergroup comparison from D0 to D6
A comparison between the groups related to the mean RD did not give significant results with P = 0.12 at D3 and P = 0.08 at D6 respectively. Similarly, the mean RW between the groups also did not give significant results with P = 0.12 at D3 and P = 0.05 at D6, respectively [Table 4]. Intergroup comparison related to the mean PD also yielded insignificant results with P = 0.95 at D3 and P = 0.81 at D6, respectively. The intergroup comparison of mean CAL values also was insignificant with P = 0.28 at D3 and P = 0.19 at D6, respectively. Though the PRC improved in all three groups from D3 to D6 on intergroup comparison the results were not significant statistically with P = 0.05 at D3 and P = 0.11 at D6 [Table 5]. VAS scores improved in all three groups and were statistically significant. On intergroup comparison it was observed that the VAS score improved significantly in group 2, followed by group 1, and finally in group 3. Therefore, pain perceived by the patients was least in group 2 (CAF+AM) [Graph 1].
|Table 4: Intergroup comparison of RD and PD from D0 to D6 using repeated two-way analysis of variance|
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|Table 5: Intergroup comparison of PD, CAL, and PRC from D0 to D6 using repeated two-way analysis of variance|
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| Discussion|| |
In this study, the test groups demonstrated overall significant improvement in all the assessed clinical parameters including RD, RW, PRC (primary outcomes), and CAL, PD, VAS (secondary outcomes) within the groups when compared to the control group wherein CAF + root conditioning with HA was employed. Though root biomodification improved the results of the study, perhaps including a fourth group wherein CAF only would be performed would have validated the role of root conditioning in recession defects.
Root preparation before root coverage can be mechanical, chemical, or a combination of both growth factors and lasers. HA is a linear polysaccharide, which interacts with growth factors, regulates the osmotic pressure and facilitates tissue lubrication which is mandatory for tissue homeostasis. It also induces the production of pro-inflammatory cytokines by fibroblasts, keratinocytes, cementoblasts, and osteoblasts which promote the inflammatory response and consequently stimulate hyaluronan synthesis by endothelial cells.
PRF is rich in growth factors which are released from 7 to 28 days; hence, it increases the efficacy of CAF when used as an adjunctive tool. The membrane acts as a barrier preventing the ingress of gingival epithelial cells into the defect. Moreover, it has a direct role to play in increasing the angiogenesis, modulating the tissue healing and aiding in warding off inflammation. A study reviewed the additional effects of different types of autologous platelet concentrates to CAF in the treatment of gingival recessions and the study concluded that PRF could exert additional beneficial effects to CAF when compared to other platelet concentrates. Another study assessed the benefits of using the PRF and Connective tissue graft (CTG) in gingival recession with CAF technique. No significant difference could be found between PRF and CTG, except for a greater gain in keratinized tissue width obtained in the CTG group. The PRF group showed enhanced wound healing and decreased subjective patient discomfort than CTG-treated gingival recessions. This study was in accordance with the previous studies wherein PRF when used as a membrane showed significant improvement in all the clinical parameters when compared to the control group.
Amniotic membrane is immunotolerant and the pluripotent stem cells present within have the ability of differentiating into other cellular elements of periodontium making it a suitable candidate for Guided tissue regeneration (GTR). AM has excellent angiogenesis which is aided by the release of growth factors present within it. Amnion seals the surgical site preventing bacterial entry and also inhibits the polymorphonuclear cell migration, thus decreasing the response of the host. A study evaluated 18 subjects with bilateral Miller’s class I gingival recession defects. Subjects were allocated randomly to treatment with coronally positioned flap + amnion allograft (test group) and coronally positioned flap alone (control group). The clinical parameters examined were width of attached gingiva (AG), CAL, probing depth (PD), width of keratinized gingiva (WKG), length of gingival recession (RL), width of gingival recession (RW). It was observed that the mean WKG increased significantly from the baseline measurements to 3 and 6 months postoperatively in the test group. It was concluded that combined CAF and AM have additional advantages in the outcome of periodontal therapy in the management of gingival recession. Most of the studies comparing the use of AM and PRF were case reports showing that both the membranes were equally effective in recession coverage; however, some of them were of the opinion that AM exhibited certain additive advantages over the PRF membrane such as better handling properties as it is comparatively thin, enabling it to mold according to the defect anatomy and root surfaces easily and hence can be used as an alternate to PRF.
HA has been observed to have ideal properties to assist in wound healing such as early granulation tissue formation, inhibition of inflammation, promotion of epithelial turnover, and connective tissue angiogenesis. A recent study wherein HA was used as a root conditioning agent before CAF in the test group showed superior results in recession coverage over the control group wherein only CAF was performed. Thus, this study employed HA as a root conditioning agent in both the control and test groups. Though the AM group (group 2) in this study performed as well as the PRF group, it was observed that the VAS was better in the AM group, which could perhaps be related to its superior handling qualities.
Injectable PRF (I-PRF) is the liquid form of PRF. It is a bioactive agent obtained by low-speed centrifugation, and has the capacity to stimulate tissue regeneration. At high concentrations, PRF may stimulate the secretion of several growth factors and trigger fibroblast migration. A study conducted employed I-PRF as a root conditioning agent before free gingival graft placement (FGG) in the test group and only free gingival graft placement in the control group. It was observed that the mean root coverage was 83.16 ± 18.48% for the control group and 88.35 ± 15.64% for the test group (I-PRF + FGG).
Future research could focus more on the latest advances in instrumentation and also include improvisation in CAF technique with tunneling, and the use of injectable PRF to gain more insight into the benefits of the same.
| Limitations|| |
The sample size was small. Moreover, the follow-up was only for 6 months and the study did not follow a split-mouth design.
| Conclusion|| |
This study reiterated that both the test groups (PRF and AM with root conditioning + CAF) performed better than the control group (root conditioning +CAF only). Perhaps adding a fourth group wherein CAF only would be done could have validated the role of root conditioning. However long-term studies with large sample sizes are required to gain insight into the beneficial effects of root biomodification for root coverage procedures using CAF.
We would like to thank Mr. Sai Kumar and Mr. Praveen for helping us compile the statistical data for this study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
KRR and AK conceived the ideas, contributed to data collection and analyzed the data. KRR led the writing and critically revised the manuscript and gave final approval.
Ethical policy and institutional review board statement
The ethical policy was followed and the study was approved by the institutional review committee (PMVIDS & RC/IEC/PERIO/DN/0287-19). and was also registered with CTRI/2020/10/028753.
Patient declaration of consent
Informed consents were taken from the participants prior to enroll them in the study.
Data availability statement
Data of study are available upon appropriate request to the corresponding author.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]