Journal of International Oral Health

: 2020  |  Volume : 12  |  Issue : 4  |  Page : 313--322

Comparative evaluation of bioabsorbable collagen membrane and platelet-rich fibrin membrane in the treatment of localized gingival recession: A randomized clinical trial

Pratibha Shashikumar, Ullas Pezhugattil Menon, Swet Nisha, Pragyan Mohanty, Sourav Chandra 
 Department of Periodontology, J.S.S. Dental College & Hospital, J.S.S. Academy of Higher Education & Research, Mysuru, Karnataka, India

Correspondence Address:
Dr. Swet Nisha
Room No. 9, Department of Periodontology, J.S.S. Dental College & Hospital, J.S.S. Academy of Higher Education & Research, Mysuru, Karnataka.


Aim: Gingival recession leads to root surface exposure and dentin hypersensitivity, which might cause an aesthetic impairment. This randomized trial was carried out for comparison and evaluation of the utility of bioresorbable collagen membrane (CM) and platelet-rich fibrin (PRF) membrane in the treatment of localized gingival recession. Materials and Methods: A total of 36 subjects having localized gingival recession were randomly allocated from Department of Periodontology, Jagadguru Sri Shivarathreeshwara Dental College and Hospital, Mysuru, Karnataka, India, in two treatment groups, namely coronally advanced flap (CAF) combined with bioresorbable CM and CAF combined with PRF membrane. Plaque index, recession height (REC) and width of keratinized gingiva, and clinical attachment level were recorded at baseline, 1, 3, and 5 years. Results: The primary outcomes of the study were REC and complete root coverage (CRC). In the CAF + CM group, at the baseline, the residual REC was 3.01 ± 0.98 mm, after 1 year, it was 1.15 ± 0.88 mm, and 5 years later, it was 1.10 ± 1.04 mm; and in the CAF + PRF group, at the baseline, REC was 2.90 ± 0.52 mm, after 1 year, it was 0.45 ± 0.67 mm, and after 5 years, it was 0.38 ± 0.56 mm. Follow-up of 5 years showed statistically significant differences between the groups. After 5 years of follow up, in CAF + CM group, 60% of teeth showed CRC, and in CAF + PRF membrane group, 70% of teeth showed CRC. When we considered REC, statistical significant difference was observed between both the groups for the localized recession treatment; after 5 years, percentage of teeth presenting CRC showed no significant difference. Follow-up of 5 years showed differences, which was statistically significant between the groups. Conclusion: Though the usage of both the membranes showed satisfactory results, the PRF membrane promised to be a better alternative to CM. Also, PRF membrane could be a cost-effective alternative in the treatment of localized gingival recessions.

How to cite this article:
Shashikumar P, Pezhugattil Menon U, Nisha S, Mohanty P, Chandra S. Comparative evaluation of bioabsorbable collagen membrane and platelet-rich fibrin membrane in the treatment of localized gingival recession: A randomized clinical trial.J Int Oral Health 2020;12:313-322

How to cite this URL:
Shashikumar P, Pezhugattil Menon U, Nisha S, Mohanty P, Chandra S. Comparative evaluation of bioabsorbable collagen membrane and platelet-rich fibrin membrane in the treatment of localized gingival recession: A randomized clinical trial. J Int Oral Health [serial online] 2020 [cited 2020 Sep 23 ];12:313-322
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Gingival recession presents with loss of soft and hard tissue. The apical displacement of marginal gingiva from cementoenamel junction (CEJ) with the presence of no active periodontal disease may not result in tooth loss, but it is usually associated with dentinal hypersensitivity, susceptibility to root caries, and aesthetic compromise.[1] Therefore, obtaining tangible root coverage (RC) becomes an integral part in the treatment of mucogingival problems in periodontal therapy.

Gingival biotype, oral hygiene habits and instruments, anatomical factors, orthodontic appliance, and oral piercing can be considered as etiological factors, causing gingival recession. Gingival recession can cause dentin hypersensitivity, increased risk of cervical lesions, aesthetic problems, and difficulty in oral hygiene management.[2],[3]

Several surgical treatment modalities, such as a coronally advanced flap (CAF), subepithelial connective graft, and pedicle flaps, have been used for gingival recession treatment. Use of guided tissue regeneration membranes, as an alternative to connective tissue graft (CTG), is being tried with variable results. Zucchelli et al.[3] used collagen membranes (CMs) in deep recession type defects to avoid the discomfort of second surgical sites as in case of CTGs. CM acts as a fibrillar scaffold, facilitating vascular and tissue in growth, biocompatible, and has hemostatic properties.[4]

Collagen is the main structural component of connective tissues. It is a major protein present in the tendons, ligaments, and cornea, and it forms the matrix of bones and teeth. The collagen matrix has shown to promote the regeneration of keratinized gingiva around teeth and implants when used with tissue augmentation procedures.[5] However, recent research has focused on the development of regenerative therapy, which is autologous in origin, thereby reducing the chances of cross-contamination and being cost-effective. Thus, the quest of autologous materials resulted in the development of platelet-rich fibrin (PRF) by Choukroun et al.[6]

PRF is a second-generation platelet concentrate, which is widely used in various periodontal regenerative procedures including RC. PRF contains various polypeptide growth factors such as vascular endothelial growth factor, platelet-derived growth factor, and insulin-like growth factors, which promote proliferation and differentiation of cells involved in periodontal wound healing.[7],[8] Various studies have confirmed the three-dimensional (3D) structure of PRF membrane, which contains a fibrin mesh into which the cytokines get entrapped resulting in angiogenesis.[9],[10] Angiogenesis is one of the crucial factors that determines the healing and maturation of soft tissues. During the centrifugation process for the PRF membrane formation, the platelets are activated, undergo degranulation, and release a large amount of cytokines.[11] The 3D meshwork of fibrin observed in PRF concentrates enables a sustained release of cytokines, which helps in the healing of tissues.[12] It also acts as an interpositional membrane and prevents the early gingival epithelium invagination.[12] These properties of PRF make it a novel biomaterial in the gingival recession treatment.

PRF is been used in regenerative periodontal therapy, recession defects, implantology—sinus floor augmentation, ridge deficiencies, and intrabony defects.[13],[14]

Among a variety of surgical techniques, CAF is the ideal surgical procedure in the presence of sufficient keratinized gingiva apical to the recession defect. Adequate RC, appropriate color match, and healing with the original alignment of the soft-tissue margin can also be achieved with CAF.[15] Therefore, the CAF is very convincing in treating localized and multiple gingival recession. It is further reported that CAF with PRF combination may show better success compared to other techniques owing to the properties of PRF. Hence, this study aimed to compare and evaluate the use of bioresorbable CM and PRF membrane in the treatment of localized gingival recession for an interim of 5 years.

 Materials and Methods

Study design

All subjects were selected from Department of Periodontology, Jagadguru Sri Shivarathreeshwara (JSS) Dental College and Hospital, Mysuru, Karnataka, India, between August 2013 and March 2014. A total of 38 patients having localized Miller’s Class I or Class II recession were screened for the study [Figure 1]. All subjects signed informed consent form.{Figure 1}

Sampling criteria

All the subjects considered were periodontally and systemically healthy individuals and fulfilled the following criteria:

Subjects having Millers Class I or Class II localized gingival recession measuring 2 mm or more were screened for the study

Full mouth bleeding and plaque score < 20%, that is, periodontally healthy subjects

Localized gingival recession located on incisors, canine, premolar, or molars

No decayed or restored teeth, only vital teeth were considered

No surgical periodontal therapy in last 2 years on the involved site

Identifiable CEJ

Subjects who responded well to maintenance therapy were included in this study

Pregnant and lactating women, subjects having history of drug intake in past 3 months, and smokers were excluded from the study. Any systemic conditions (like uncontrolled diabetes mellitus, uncontrolled hypertension, abnormal liver function) having relative or absolute contraindications to surgery

This was a randomized controlled trial having two groups assigned randomly as control group (CAF + CM) and test group (CAF + PRF) using computerized generated randomization table and GraphPad random number calculator.

Clinical measurement

The clinical parameters that were recorded by calibrated examiner, blinded to the surgical treatment (SN) included plaque index (PI), gingival thickness (GT), width of keratinized gingiva (WKG), relative attachment level (RAL), and root coverage(RC). The WKG was measured from the free gingival margin to the mucogingival junction (MGJ). Measurement of GT was carried out using #15 endodontic reamer with a rubber stopper. The reamer was inserted perpendicular under local anesthesia 2 mm below the gingival margin, and then the thickness was measured to the nearest 0.1 mm using a caliper.[16]

All the measurements were recorded using the UNC-15 probe. Acrylic stents were made to guide the position of the probe in the midfacial line of the selected teeth.

After Phase I therapy, the patients underwent the assigned treatment and were recalled after 10 days and again at 1, 3, and 5 years postoperatively to evaluate the clinical parameters. At 1 year post treatment, percentage of RC was calculated according to the following formula.[17]



Following three types of incisions were used and a trapezoidal flap was designed.[18]

Primary incisions were made at the base of interdental papillae mesially and distally with reference to CEJ extended to 1 mm of the proximal line angle of the adjacent teeth, this incision leaves the interdental papilla intact. A sulcular incision was then given, which connected the primary incisions [Figure 2]A and [Figure 3]A. Vertical diverging incision, extending apically from each end of primary incision, was directed toward alveolar mucosa [Figures 2B] and [3B].{Figure 2} {Figure 3}

Full–partial thickness flap was elevated using number 15 blade. Complete mobilization of the flap was achieved, as no tension was present when the flap was pulled coronally beyond the CEJ. This passive placement of flap helped in proper flap stabilization while suturing.

The flap was reflected and the root surface was planed using curette and any convexity of the root surface was reduced. De-epithelialization using number 15 blade was carried out on the intact papillae mesially and distally to the recession. Periodontal probe was used to measure the length and width of the membrane to be placed on the surgical area.

In the CAF + CM group, trimming and contouring of sterile CM was carried out, at least 2 mm of the bone, to cover the recipient site [Figure 2C]. Sterile moist gauze was applied for 5 min with firm pressure over the CM adhering to the recipient site. The membrane was sutured using resorbable sutures (Vicryl 4-0, Ethicon). The CM was covered by coronally repositioning the flap pedicle completely to cover it, and placed in position using sling sutures into the mesial and distal papillae and interrupted sutures for vertical releasing incisions [Figure 2D].

Preparation of platelet-rich fibrin membrane

The PRF membrane was prepared in accordance with the Choukroun protocol.[6] A total of 10 mL of intravenous blood was drawn from antecubital vein by venipuncture of the antecubital vein was drawn from the patient and collected in the centrifuge tubes without anticoagulant. Immediately it was centrifuged using a bench top centrifuge (Remi 8c) for 10 min at 3000rotations per mintue.[8] The fibrin clot was separated from the RBC base using sterile tweezers and scissors. This fibrin clot was placed in the PRF box (PRF Box, Process, Nice, France) for the preparation of the PRF membrane [Figure 2E].

Placement of platelet-rich fibrin membrane on the recipient site

The PRF membrane was placed on the recipient site, and finger pressure was used for stabilization of the membrane [Figure 3C]. Then the overlying full–partial thickness flap was positioned over the membrane and sutured using sling sutures and interrupted sutures for vertical releasing incisions [Figure 3D].

Coe-Pak as periodontal dressing was placed on the surgical area in both the groups.

Postsurgical care

The periodontal dressing (Coe-Pak) was placed on the surgical site in both the groups.

Each subjects were prescribed amoxicillin 500mg/day for 5 days and 0.12% chlorhexidine digluconate rinse twice a day for 1 min for 3 weeks. Aceclofenac 100mg was prescribed twice daily for 3 days for pain management. Brushing at surgical sites by patients was avoided for 3 weeks. Standard oral hygiene procedures were reintroduced subsequently and ultrasoft brushes were instructed to be used for 3 weeks. During the first 8 days, subjects evaluated their pain on a visual analog scale (VAS) given to them immediately after surgery.

Clinical outcomes

All the measurements were recorded by one clinician (UM) using UNC 15 probe (Hu-Friedy) and a stent made at baseline for reference.

The primary outcomes in the study were gingival recession height (REC), measured mid-facially from CEJ to the gingival margin, and CRC (absence of gingival recession with the CEJ not visible) of percentage of teeth at each visits. The secondary outcomes evaluated were PI, gingival thickness, WKG, measured from the free gingival margin to the MGJ, percentage RC, tooth hypersensitivity (SEN), which was evaluated with questionnaire dichotomous response (yes/no) after 3s of airflow application, and RAL, evaluated as the sum of REC and probing depth. Aesthetic outcome was evaluated by a blinded examiner (PM) with the RC aesthetic score (RES) described by Cairo et al.[19] measured on a scale of 1 to 10, with 10 being a perfect score, and postoperative pain assessment was carried out using VAS score.

Statistical analysis

The statistical analysis was performed by a single clinician (SN) blinded to the surgical techniques using the Statistical Package for the Social Sciences (SPSS) software (SPSS for Windows, Version 16.0, SPSS Inc., Chicago, IL). Shapiro–Wilk test was used for the assessment of normality of distributions. Descriptive statistics were evaluated for all primary and secondary outcomes as mean values and standard deviation. At baseline, 1, 3, and 5 years intragroup comparison was evaluated using analysis of variance, whereas for intergroup comparison, unpaired Student t test was used. Intergroup differences at baseline were evaluated using Fisher’s exact test for dichotomous variables. The level of significance was at P > 0.05.


A total of 36 subjects were treated, 18 in each group, and they attended the last follow-up visit 5 years after the surgical procedure. Two treated cases of CAF + CM and CAF + PRF groups are shown in [Figures 2] and [3], respectively. Demographic baseline characteristics are presented in [Table 1]. Primary and secondary outcomes over a period are shown in [Table 2] and [Table 3].{Table 1} {Table 2} {Table 3}

At 1-year of follow-up, recession width decreased, and till 5 years, it remained stable. After 3 and 5 years, REC significantly favored CAF + PRF [Figures 2F] and [3]E]. After 5 years of follow-up, CRC percentage was lower in the CAF + CM group at 5 years, though this difference was statistically insignificant (P > 0.05).

When secondary outcomes were considered the WKG remained stable overtime but CAL decreased significantly at 1 year. Intergroup comparison for hypersensitivity showed no significant difference in both the groups.

After 1 year in CAF + PRF group, recession coverage percentage was significantly higher. The mean RES score for the test sites was 8.5 ± 1.2, and for control sites, it was 8.71 ± 1.4 (P > 0.5), which was significant for both the cases. The distribution of pain VAS scores associated with CAF + CM and CAF + PRF was between 2 and 5 (mild to moderate pain), with pain lasting for a maximum of 7 days for both the groups. PI score was 2.02 ± 0.67 in CAF + CM and 2.18 ± 0.67 in CAF + PRF after 5 years, this difference was statistically insignificant (P > 0.05). GT was 1.04 ± 0.54 in CAF + CM and 1.03 ± 0.52 in CAF + PRF after 5 years, statistically intergroup comparison was nonsignificant.


The success criteria for RC procedures include objective outcomes such as percent RC, complete RC, and also subjective outcomes—patients aesthetic satisfaction in terms of color match and intra- and postoperative discomfort. Surgical techniques aim at increased predictability of RC, reduced number of surgical sites, and improved patient comfort, aesthetics, and reconstruction of the lost periodontal tissues.

PRF has a concentrated suspension of growth factors that are involved in wound healing and promotion of regeneration.[20 Apart from playing a role in regeneration],[ these factors also modulate and upregulate the function of other factors.[21] This study aimed at investigating the clinical applicability of PRF membrane in comparison to a bioabsorbable CM for RC in localized recession coverage. There was complete RC in 80% of teeth at 1 year and 70% at 5 year in the PRF group.

The width of KG showed significant increase in both the treatment groups. Root conditioning agents have been highly recommended for their ability to decontaminate root surfaces, remove endotoxins and other bacterial by-products, eliminate the smear layer, expose collagen fibrils and dentinal tubules, and further promote new attachment.[22] This can be conducted mechanically or chemically using acid-based materials. However, root preparation in this study was restricted to mechanical scaling and root planning to avoid any possible influence of the root conditioner on the membranes. PRF offers several advantages over other membranes when used for regeneration, it offers cost-effectiveness, no secondary surgical site needed for tissue donation, relatively less surgical time required for acquisition, ease of suturing, and favorable cells such as cytokines, immune cells, and factors such as cytokines and growth factors for regeneration. Several studies have shown that when PRF was applied at surgical sites there was reduction in postoperative symptoms[23],[24] like pain, swelling and stimulation of matrix biosynthesis and angiogenesis which results in acceleration of tissue healing.[25] However, as compared with other grafts, such as CTGs, PRF has rapid degradation, which leads to reduced release of molecules[23] and interference with the early stabilization of periodontal tissues. Still CTG remains the gold standard in the gingival recession treatment.[15],[26]

The use of bioabsorable CM is advantageous as there is no need of removal of membrane unlike nonresorbable barrier membrane which requires surgical reentry for its removal This reduces chair side time, chances of infection, and cost, and increases patient acceptability toward the treatment. When we place a bioresorbable membrane, bone and/or periodontal ligament migration peaks in 2–7 days after surgery and the mitotic activity decreases initially with almost normal levels by the end of 3–4 weeks.[27] Selective cell population needs 3–4 weeks, which is sufficient in case of placement of bioresorbable membrane to retain its integrity and tissue regeneration. In this study, 70% complete RC was observed at 1 year in the collagen group and 60% at 5 years [Figure 4].{Figure 4}

Complete RC results in decrease in hypersensitivity, increase in aesthetic factors, patients comfort, and treatment predictability. Both the groups with CAF + CM and CAF + PRF techniques showed significant percentage of RC. This study showed mean percentage of RC as 68.11 ± 31.7 in the CAF + CM group, and in CAF + PRF group, it was 85.20 ± 14.2 in 1-year follow-up, which was significant; however, at 3 and 5 years, it was statistically insignificant [Figure 5]. Similar results were observed in 5 years of follow-up study conducted by Francetti et al.[28] No studies have been reported to evaluate the GT values using CAF + PRF in the treatment of localized gingival recessions. In this study, statistical significant increase in GT was observed at 6 months. An increase in GT values is expected after subepithelial connective tissue graft (SCTG),[29] but both in PRF and CM group there was increase in GT, though no significant difference was observed between the groups.{Figure 5}

Various outcomes and results might be due to difference in surgical procedures used in gingival recession treatment. In this study, KTW increase in both test and control groups was in agreement with the previous report by Öncü[29] and Eren and Atilla.[14] In the control group, the gain in KTW could be due explained by membrane placement, which delays the epithelial migration and determines the character of the surface epithelium. In the test group, PRF accelerated regeneration as it contains several growth factors, which in turn influences tissue proliferation and manifestation. However, further histological studies are required to confirm this statement.

In secondary outcomes except for recession height, which was significantly better in CAF + PRF group compared to CAF + CM group, all other parameters were not significantly different. For adequate interpretation of the results, all surgical interventions were performed by the same clinician, and adequate sample size was taken.

A long-term prospective follow-up study for 8 years in large sample size with CAF showed that the recession height gradually decreased over time, from 0.3 ± 0.5 mm after 6 months to 0.9 ± 0.9 mm after 8 years.[30]

Complete treatment success for CAF technique can be stated when the gingival margin position and probing depth are coronal to the CEJ.[31] By this standard, in this study, by CAF + CM technique, only 60% coverage, and by CAF + PRF technique, only 70% coverage of teeth was obtained.

Limitations for this study were external validity of the results, as all the surgical procedures were performed by the same clinician, as similar results were observed in another study on the same topic.[32]

Second, histologic assessment of type of defects was not carried out due to ethical considerations. Third, most of the gingival recession depth treated was shallow, with a recession depth of around 2–3 mm (3.01 ± 0.98 for CAF + CM group and 2.90 ± 0.52 for CAF + PRF group). Lastly, qualification or quantification of PRF, which can help analyze the growth factors, cytokines, or other biomolecular components levels, was not considered, so generalization cannot be done for standard comparison with other studies.

The strength of the study was the long period of follow-up, which gave us an idea about the stability of the results achieved. Patient-centered clinical outcomes, such as dentin hypersensitivity, VAS score, and aesthetic score (RES), were taken into the consideration.

Further studies are required to evaluate healing pattern as a potential parameter related to the efficacy of PRF use in gingival recession treatment.

In both CAF + CM and CAF + PRF techniques in relation to REC, significant difference was seen; however, in proportion of teeth presenting with CRC after 5 years of follow-up, no significant difference was seen. Significant reduction in REC, which appeared to remain stable over 5 years as observed for both the surgical techniques, is predictable for the gingival recession treatment.

The use of autologous membranes that is rich in growth factors, such as PRF, is increasing in the field of periodontology. The benefits of its usage are that PRF offers dense autologous membrane, rich in growth factors, which favors regeneration. This study evaluated the effects of the use of PRF and compared the use of CM on the treatment of gingival recession. Within the purview of this study, PRF membrane provides sufficient graft material for RC procedures and also avoids adverse effects as it is prepared from patient’s own blood.


The authors acknowledge all the participants for their contribution towards data collection used in the present paper.

Financial support and sponsorship

This study was self-funded.

Conflicts of interest

The authors declare that they have no competing interests.

Authors contributions

Pratibha Shashikumar(PS), Ullas Pezhugattil Menon(UM) designed the study and ensured approval of the Ethical Commitee. PS and UM collected the clinical photographs and recruited participants for the assessment sessions. The surgical procedures were performed by UM.The assessment sessions were organized by Pragyan Mohanty and Sourav Chandra. PS and Swet Nisha analyzed the data and the results were discussed and interpreted in a meeting with all authors. The authors read and approved the final manuscript.

Ethical policy and institutional review board statement

The study was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2000, and the study and the study protocol were approved by the institutional ethical committee of JSS University, Mysuru, Karnataka, India (DCH/PGS/2013–2014.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Data availability statement

The data that support the findings of this study are available from the corresponding author on request.


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