Evaluation of Socket Preservation Using Collagen Plug and Injectable Platelet Rich Fibrin in Extracted Sockets of Mandibular Molars: A Split Mouth Study

A B S T R A C T

Aim and Objectives: Evaluation of socket preservation using collagen plug and injectable platelet rich fibrin in extracted sockets of mandibular molars. To evaluate wound healing and bone density using collagen plug and I-PRF and to compare wound healing and bone density between collagen plug and I-PRF.
Methodology: This experimental study involves 13 healthy patients at the Sibar Institute of Dental Sciences and Hospital in Guntur, Andhra Pradesh, India, who underwent mandibular molar extraction under local anesthesia. Patients underwent clinical and radio-graphic examinations and received periodontal treatment. The study involved extraction of right and left mandibular molar teeth, AbGel placement, collagen plug placement, and sockets secured with sutures and pressure packs. Postoperative pain, swelling, and wound healing were assessed using Wong-Baker faces pain rating scale, VAS scale, and LANDRY healing index. CBCT was obtained after 1 month and 3 months after extraction for bone quality assessment.
Results: In the study, there were 69.2% men and 30.8% women. According to the study, 14.3% of individuals in the collagen plug group and 85.7% of those who received injectable platelet-rich fibrin experienced very good wound healing. On the first and seventh days, the mean pain intensity was lower in the injectable group, but there was not a noticeable distinction between the groups. The injectable group had the lowest swelling score, but by day seven, it had dramatically decreased. At the third month, the collagen plug group had the highest bone density readings, with no discernible difference between the groups.
Conclusion: It can be concluded that I-PRF can be utilized as an alternative to collagen plug.

Keywords

Biocompatible materials, collagen, guided tissue regeneration, socket bone healing

Introduction

When a tooth is deemed to be irrestorable, clinically, surgical extraction may be indicated. Edentulous sites can have a negatively affect patient quality of life and cause substantial anatomical changes to the alveolar ridge after the tooth is removed [1, 2]. It is proven fact that every tooth extraction leads to compromised alveolar bone [3]. Alveolar ridge resorption is a chronic, irreversible circumstance that caused a reduction in width varying from 2.6 to 4.6 mm and height ranging from 0.4 to 3.9 mm postextraction [4-6]. The majority of the alveolar bone resorption method varies within the first 3 to 6 months after extraction, however this practice is chronic, and the alveolar bone continues to resorb 25 years after the extractions [7]. Resorption rate varies from person to person and even from period to period for the same person. The resorption process differs between bones of maxilla and mandible noticeably, with the sockets of mandible which resorbs up to four times quicker than the socket of maxilla [5, 7].

In order to provide a platform for osteoblastic activity, induce bone formation at the site, and preserve the appropriate height of the alveolar ridge for future implant insertion, the grafting material should ideally be biocompatible and osteoconductive [8]. Materials for alveolar ridge preservation such as hydroxyapatite, beta-tricalcium phosphate, polylactide sponge, and Bio-Oss produce a variety of results. However, no substance has been found to be continually discovered benificial alveolar bone conservation [9-11]. Studies of intraalveolar treatment with different materials have shown that the placement of appropriate materials is more beneficial than the natural unloading of the alveoli [12, 13].

Filling the post-extraction socket with type-1 collagens helps to prevent complications by forming new granulation tissue, stabilizing blood clots, and protecting the wound. In the extraction sockets, blood clots provides scaffolds for new blood vessel and promote wound healing. The commonest filling material that can be utilised to control alveolar bone retention is the collagen plug. The pure type-1 collagen plug facilitates healing process in socket by maintaining the blood clot in the extraction socket, generating new granulation tissue and enough porosity for post-operative blood penetration. To conclude the technique of injecting pure type 1 collagen placed in post extraction socket has gained popularity over time [14].

In both dental and medical fields, there is always an innovative path for invention of advanced techniques based on different procedures and it is a never-ending process. Studies showed the impact of blood cells on biomaterials used in the human body have been conducted. This evolution began in the late 1990s with the centrifugation of platelet-rich plasma (PRP), and was followed by next generation of platelet aggregates, platelet-rich fibrin (PRF), till the latest advanced platelet-rich fibrin clot (a-PRF) [15, 16]. Platelet aggregates in injectable form are now widely used to achieve favorable results. Injectable PRF (i-PRF) is a latest PRF matrix obtained from venous blood by low centrifugation forces and shorter centrifugation times. Injectable PRF (i-PRF) contains a variety of growth factors and inflammatory cells that are important for tissue regeneration [17]. It has been used to treat extraction sockets, gingival recessions, palate wound closure, periodontal defect regeneration, and hyperplastic gingival tissues. Better wound healing, enhanced angiogenesis, lower cost effective, and perfect immune-biocompatibility are all advantages of injectable PRF [18,19]. However i-PRF can be utilized as adjuvant regenerative material with structural variations as particles or as a block graft material, which is not often indicated in regenerative dentistry, yet. With this context the respective study conducted to evaluate the socket preservation placing collagen plug and injectable platelet rich fibrin in extracted sockets of mandibular molars.

Methodology

This study was designed as experimental study undertaken in the Department of Oral and Maxillofacial Surgery, Sibar Institute Of Dental Sciences and Hospital, Guntur between the period of February 2021- September 2022, after approval of the Institutional Ethics Committee (ECR/1362/Inst/AP/2020).

I Study Population

Thirteen healthy patients who attended to the Department of Oral and Maxillofacial Surgery, Sibar Institute Of Dental Sciences and Hospital, Guntur without deviations from normal vital signs, measured in the preoperative period who required mandibular molar extraction under local anesthesia and who were willing to participate and sign an informed consent form, were selected for the study. Pregnant and lactating women and expected cases of traumatic extraction were not included in the study. Prior to the study, all patients underwent clinical and radio-graphic examination and received periodontal treatment as needed.

II Study Procedure

Participants were selected based on inclusion and exclusion criteria. Right and left mandibular molar teeth were extracted using 2% lignocaine hydrochloride containing 1:80000 adrenaline. With an interval of one week. AbGel was placed in the right molar socket, soaking in I-PRF. Collagen Plug was placed on the left side, and sockets secured with figure of eight sutures and a pressure pack. Patients were recalled on 1^st and 7^th postoperative days for the assessment of pain and swelling using Wong-Baker faces pain rating scale and VAS scale, while wound healing was assessed using LANDRY healing index [20-22]. CBCT was obtained after 1 month and 3 months after extraction for assessment of bone quality.

III I-PRF Preparation

Scrub the area with iodine at the site of penetration of needle and 10ml venous blood of the patient had taken and centrifuged at the speed of 700 rpm for 180 seconds. This low speed centrifugation had divided I-PRF and RBC. On the top of the test tube I-PRF seen and carefully I-PRF is collected from the tube with a syringe and placed in the extraction socket by soaking in AbGel and figure of eight sutures will be placed (Figures 1-6).

IV Statistical Analysis

Data was compiled using Microsoft excel software and analyzed using statistical package for social science (SPSS Version 25). Descriptive statistics were used to summarize the results. Kolmogorov Smirnov tests revealed that the study data were non-normally distributed, and hence non-parametric tests were employed to compare the study parameters between both the groups and tests used were Man-Whitney U test and Friedman test.

Results

The mean age of the male subjects was 23.11±4.8 years. The mean age of the female participants was 25.25±3.2 years. Overall mean age of the participants was 23.7±4.36 years. Among the study subjects 30.8% of the participants were females where as 69.2% of them were males (Table 1). Table 2 depicts the comparison of wound healing on 7^th day follow-up between both the groups.85.7% of the subjects in injectable platelet rich fibrin group achieved very good wound healing where as in collage plug group only 14.3% achieved very good wound healing and the difference observed between both the groups was statistically significant (P=0.037). The mean pain intensity was lower in the injectable platelet rich fibrin group on 1^st day and 7^th day when compared with collagen plug group and there was no statistically significant difference observed between both the groups ((P=0.245) and (P=0.095)),while comparison of intensity of pain in injectable platelet rich fibrin group and also in collagen plug group at different time intervals revealed a statistically significant difference between 1^st day and 7^th day follow-up (P=0.001 and 0.008) (Table 3).

Table 1: Descriptive statistics regarding age and gender of the study subjects.

	Age		Gender
	Males	Females	Males	Females
Descriptives of the study subjects	23.11±4.8	25.25±3.2	69.2%	30.8%
Overall mean age	23.7±4.36

Table 2: Comparison of wound healing between two groups.

Group	good	Very good
Injectable platelet rich fibrin	36.8%	85.7%
Collagen plug	63.2%	14.3%
P value	0.037*

Chi-square test p≤0.05 was considered statistically significant.

*denotes statistically significant.

Table 3: Comparison of intensity of pain at 1^st and 7^th day between both the groups.

Follow-up	Injectable platelet rich fibrin	Collagen plug	Z score	P-value
1st day	11.92	15.08	-1.163	0.245
7th day	11.27	15.73	-1.670	0.095
Sum of Ranks	91.00	61.50	-	-
P-value	0.001*	0.008*	-	-

Man-Whitney U test; Wilcoxon sign rank test ;p≤0.05 was considered statistically significant.

Table 4 depicts the comparison of swelling at 1^st and 7^th day between both the groups. The mean swelling score was lowest for injectable platelet rich fibrin group when compared with collagen plug group and the difference was not statistically significant (P=0.23). On 7^th day follow-up an decrease in swelling observed in both the groups and the difference observed was statistically significant (P=0.006). A significantly reduced swelling was observed from 1^st day to 7^th day follow-up in both the groups (P=0.001). Highest bone density values were observed for collagen plug group on 3^rd month follow-up (717.23). There was no statistically significant difference seen between injectable platelet rich fibrin group and collagen plug group on both 1^st month and 3^rd month follow-up (P≥0.05). Comparison of bone density at different time intervals reveals a significant increase in bone density from 1^st month to 3^rd month follow-up (P=0.001) in both the groups (Table 5). Changes in bone density was observed in the extraction site from 1^st month to 3^rd month follow-up after placement of iprf and collagen (Figures 7-10).

Table 4: Comparison of swelling scores of two groups at 1^st and 7^th day between two groups.

Follow-up	Injectable platelet rich fibrin	Collagen plug	Z score	P-value
1st day	11.96	15.04	-1.180	0.238
7th day	9.62	17.38	-2.766	0.006*
Sum of Ranks	91.00	78.00	-	-
P-value	0.001*	0.001*	-	-

Man-Whitney U test; Wilcoxon sign rank test ;p≤0.05 was considered statistically significant.

Table 5: Comparison of bone density scores at 1^st month and 3^rd month between two groups.

Follow-up	Injectable platelet rich fibrin	Collagen plug	Z score	P-value
1st month	11.00	16.00	-1.667	0.096
3rd month	11.62	15.38	-1.256	0.209
Sum of Ranks	78.00	91.00	-	-
P-value	0.001*	0.001*	-	-

Man-Whitney U test; Wilcoxon sign rank test ;p≤0.05 was considered statistically significant.

Discussion

Teeth are crucial for bone health and are often extracted for various reasons, including root fractures, periapical pathologies, periodontal disease, and extensive decay. Tooth extraction leads to disuse atrophy of surrounding alveolar bone, causing shrinkage and receding gums. Alveolar bone loss can result from facial trauma, endodontic pathology, periodontitis, and extraction techniques. To minimize bone loss, socket preservation is introduced, using a synthetic biomaterial to stabilize blood clots, prevent tissue reduction, and provide a scaffold for cellular and vascular growth [23, 24]. Socket preservation materials include autograft, allograft, and xenograft. Autograft Bone promotes new bone formation, while allograft bone comes from different species. Xenograft is biologically derived from animals, corals, or algae [23]. Collagen, a major component of connective tissue, provides structural aid and stimulates platelet adhesion. Type-1 collagen is used for post-extraction socket preservation, reducing complications and protecting the wound. A novel technique for socket preservation is the use of a collagen plug, a cylindrically shaped sponge that stabilizes blood clots, insulates bone, and helps in hemostasis at the extraction site. Collagen plugs are used for soft tissue healing and hard tissue reconstruction [25, 26].

PRP, introduced two decades ago, is a concentrated source of growth factors used in tissue engineering and wound healing. It provides a scaffold for periosteal cells in vitro, promoting osteogenesis, osteoinduction, and osteoconduction. Gelfoam packing is not effective in fibroblast growth or mitosis. G-graft, made from natural low crystalline hydroxyapatite, serves as a scaffold for growing cells and strengthens clots. It is porous and can be re-sterilized. Regenerative dentistry has become the standard of care, with PRF prepared from patient's blood for faster bone regeneration and better healing. I-PRF was developed to address this issue by incorporating liquid protein concentrate, anticoagulants, and fibrin matrix [27, 28].

Ghanaati et al. developed a low-speed concept for blood centrifugation, revealing that lower centrifugation speeds increased cell count, including leukocytes, before fibrin clot formation [29]. This led to the development of i-PRF, a new platelet aggregate alternative in medicine and dentistry. It is autogenous, reduces adverse reactions, and can bond with biomaterials for bone grafting. Liquid PRF is cost-effective and comparable to bovine-derived fibrin. I-PRF is used in dermatology, cosmetology, implant dentistry, but studies on its effectiveness for socket preservation are limited [30, 31]. In this context, the current study has been carried out with the objective of assessing socket preservation using collagen plugs and injectable platelet rich fibrin in extracted mandibular molar sockets. The present study includes 13 patients who underwent bilateral mandibular molar extractions, with I-PRF soaked in gel placed in the extraction socket on the right side and collagen plug placed on the left side. A 1-week gap was maintained between surgeries. Results showed no significant difference in pain, swelling, wound healing, or bone density between I-PRF and collagen plug.

I Pain

The pain intensity in the injectable platelet rich fibrin group was lower on the 7^th day compared to the collagen plug group. This finding is similar to previous studies involving socket filling with collagen plugs. A study done by Vincent saliba et al. where socket filling was done with collagen plug and Bio-oss concluded that Bio-Oss experienced more pain in the seven days following surgery [32]. Another study done by Shang-Jye Tsai et al. concluded that patients with collagen (type-1) insertion into the post extraction socket had markedly decreased pain than the control group, and also had notably reduced post-operative pain time scale than the control group, where the findings were similar to the current study [14]. S A Puia et al. found that textured collagen (MC) in porcine or bovine can reduce postoperative pain and improve wound healing [33]. According to Norman Shaw et al., study, all 25 participants in the collagen group showed remarkably low levels of pain [34]. Zhang et al. found that i-PRF affects immune cell responses, suppressing macrophage M1 polarization and DC maturation [35].

II Swelling

On comparing the mean swelling scores between I-PRF and collagen plug on 1^st and 7th day I-PRF has the lower score on both the 1^st and 7^th day. There was no statistically significant swelling score between both the groups on 1^st day whereas on seventh day I-PRF has the lowest swelling score and is statistically significant when compared with collagen plug. There is statistically significant difference in swelling in both I-PRF and collagen group from 1^st day to 7^th day. A study done by Hoon Cho, et al. described that collagen plugs (Type-I) are used to fill extraction wounds in order to optimize hemostasis, promote granulation tissue formation, and protect the wound surface [36]. Collagen sponges help to reduce swelling and pain after surgery. The use of collagen plugs in third molar extractions was associated with a low level of complication rates in their study. Swelling was completely reduced in eight patients on the collagen plug placed side, according to a study conducted by Murugan Ranganathan et al. [37]. Six patients had moderate swelling on the first postoperative day, three had mild swelling, and one patient had no visible swelling. The findings were not in accordance with the present study.

III Wound Healing

On comparison of wound healing on 7^th day follow-up between both the groups the I-prf group had very good wound healing of 85.7% compared to only 14.3% in collagen plug group showing statistically significant difference between both the groups in wound healing on 7^th day. Liquid PRF, consisting of autologous growth factors like PDGF, TGF-β1, and VEGF, assists in wound healing by assisting platelets and leukocytes in repairing damaged tissue. It helps in process of wound healing as it contains a number of autologous growth factors found in blood, such as platelet-derived growth factors (PDGF), transforming growth factor-beta (TGF-1) and vascular endothelial growth factor (VEGF), as well as cells (platelets and leukocytes) [38]. A study conducted by Shang-Jye Tsai et al. concluded that patients who received type-1 collagen placement into the extraction socket had significantly better wound healing and less probing depth than the control group which is not in accordance with the present study [14]. Vincent Saliba et al. in their study concluded that sockets which are filled with collagen plug has healing of upto 60% compared to biooss graft [32]. Numaan Nisar et al., found no significant difference in wound healing after extraction socket grafting with collagen plug and no graft material. Singh et al., found that sockets grafted with hydroxyapetite with collagen had less probing depth and better wound healing [39, 40]. Athanasios et al. found FDBA/βTCP and rhPDGF-BB improve wound healing compared to collagen alone, while Ahmad Kutkut et al. found MGCSH mixed with PRP improves wound healing in 10 days [41, 42].

IV Bone Density

The bone density in iprf group increased from 1^st month to third month in both IPRF and collagen group but highest bone density was found in collagen plug group on 3^rd month follow up. Jeong-Kui Ku et al. conducted a study in which socket grafting was done using DBM/rhBMP-2 and collagen and DBM/rhBMP-2 showed better bone healing than collagen [43]. In the present study there was no statistically significant difference between I-prf group and collagen plug group on both 1^st and 3^rd month follow up in terms of bone density but highest bone density was observed during 3rd month follow-up of collagen plug group.

Lydia N. Melek, et.al., compared GBR and I-PRF before implant placement to prevent bone resorption and enhance alveolar ridge dimensions [30]. She suggested injectable PRF with high growth factor composition for predictable bone formation. Kotskis et al. found that extraction sockets preserved with organic bone material had 14% resorption after 3 months. Athanasios et al. found that collagen plug, FDBA/βTCP+ collagen, FDBA/β TCP+collagen+PRP, and FDBA/β TCP+collagen+rhPDGF-BB had better healing capacity and eliminated D2 type bone formation [41]. Studies have shown that MGSCH mixed with PRP and collagen plug can increase vital bone volume at 3m. Biooss+Iprf can regenerate wide infrabony defects. I-PRF and A-PRF augmentation of ridges and sinus floor augmentation have better bone formation. DBBM+I-PRF has been found to be more effective in sinus floor augmentation [44, 45].

PRP increased osteoblast migration by a double-fold, while i-PRF induced a three-fold increase. i-PRF accelerated ALP staining and alizarin red staining, and increased mRNA levels of ALP, Runx2, and osteocalcin. It is used in facial skin regeneration and tissue regeneration. Leukocytes play an important role in tissue regeneration functions, which include stimulus of fibroblast propagation, enhance anti-inflammatory effects, angiogenesis, and protein deposition, via a cluster of mesenchymal stem cells.

Conclusion

The results showed that although collagen plugs had the highest bone density values at the third month of follow-up, there was no statistically significant difference between injectable platelet rich fibrin and collagen plug in terms of pain, swelling, or wound healing. So, it can be concluded that I-PRF can be utilized as an alternative to collagen plug.

Article Info

Article Type

Research Article

Publication history

Received: Tue 29, Aug 2023
Accepted: Tue 19, Sep 2023
Published: Thu 19, Oct 2023

Copyright

© 2023 Ganesh Sai Sandeep Kumar. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Hosting by Science Repository.
DOI: 10.31487/j.DOBCR.2023.02.01

Author Info

Ganesh Sai Sandeep Kumar L. Krishna Prasad P. Srinivas Chakravarthi P. Raja Satish Anand Vijay S Vidya Sagar B K. S. Deekshith

Corresponding Author

Ganesh Sai Sandeep Kumar
Post Graduate, Department Of Oral And Maxillofacial Surgery, Sibar Institute Of Dental Sciences, Guntur, Andhra Pradesh, India

Figures & Tables

Table 1: Descriptive statistics regarding age and gender of the study subjects.

	Age		Gender
	Males	Females	Males	Females
Descriptives of the study subjects	23.11±4.8	25.25±3.2	69.2%	30.8%
Overall mean age	23.7±4.36

Table 2: Comparison of wound healing between two groups.

Group	good	Very good
Injectable platelet rich fibrin	36.8%	85.7%
Collagen plug	63.2%	14.3%
P value	0.037*

Chi-square test p≤0.05 was considered statistically significant.

*denotes statistically significant.

Table 3: Comparison of intensity of pain at 1^st and 7^th day between both the groups.

Follow-up	Injectable platelet rich fibrin	Collagen plug	Z score	P-value
1st day	11.92	15.08	-1.163	0.245
7th day	11.27	15.73	-1.670	0.095
Sum of Ranks	91.00	61.50	-	-
P-value	0.001*	0.008*	-	-

Man-Whitney U test; Wilcoxon sign rank test ;p≤0.05 was considered statistically significant.

Table 4: Comparison of swelling scores of two groups at 1^st and 7^th day between two groups.

Follow-up	Injectable platelet rich fibrin	Collagen plug	Z score	P-value
1st day	11.96	15.04	-1.180	0.238
7th day	9.62	17.38	-2.766	0.006*
Sum of Ranks	91.00	78.00	-	-
P-value	0.001*	0.001*	-	-

Man-Whitney U test; Wilcoxon sign rank test ;p≤0.05 was considered statistically significant.

Table 5: Comparison of bone density scores at 1^st month and 3^rd month between two groups.

Follow-up	Injectable platelet rich fibrin	Collagen plug	Z score	P-value
1st month	11.00	16.00	-1.667	0.096
3rd month	11.62	15.38	-1.256	0.209
Sum of Ranks	78.00	91.00	-	-
P-value	0.001*	0.001*	-	-

Man-Whitney U test; Wilcoxon sign rank test ;p≤0.05 was considered statistically significant.

Figure 1: Blood collection FOR i-PRF.

Figure 2: Centrifugation.

Figure 3: Collecting I-PRF.

Figure 4: ABGEL soaked in i-PRF.

Figure 5: Collagen plug.

Figure 6: ABGEL.

Figure 7: Bone density of 48 region after 1M.

Figure 8: Bone density of 38 region after 1M.

Figure 9: Bone density of 38 region after 3M.

Figure 10: Bone density of 48 region after 3M.

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