|Year : 2019 | Volume
| Issue : 3 | Page : 242-248
Demineralized freeze-dried bone allograft with or without platelet-rich fibrin in the treatment of mandibular Degree II furcation defects: A clinical and cone beam computed tomography study
Aravinda Basireddy1, Santha Kumari Prathypaty2, Durga Bai Yendluri2, Santi Priya Potharaju2
1 Department of Periodontics, Sri Sai College of Dental Surgery, Hyderabad, Telangana, India
2 Department of Periodontics, Government Dental College and Hospital, Hyderabad, Telangana, India
|Date of Submission||20-Jul-2018|
|Date of Acceptance||22-Oct-2018|
|Date of Web Publication||2-May-2019|
Dr. Aravinda Basireddy
7-1-68/3/1, Opp. Rosaiah Residence, Dharam Karam Road, Ameerpet, Hyderabad - 500 016, Telangana
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Currently, there is no gold-standard regenerative material for the treatment of furcation defects. The use of bone grafts in combination with guided tissue regeneration membrane is a predictable treatment option but is expensive. Platelet concentrates are increasingly being used owing to their ease of use and cost-effectiveness. Aims: The aim of this study is to evaluate the ability of platelet-rich fibrin (PRF) to augment the regenerative effects exerted by demineralized freeze-dried bone allograft (DFDBA) in the treatment of mandibular degree II furcation defects. Materials and Methods: Twenty-eight defects in 14 patients with bilateral Degree II mandibular furcation defects were included in the study. The test group was treated with a combination of DFDBA and PRF, while in the control group DFDBA was used alone. Clinical parameters such as probing depth, relative vertical clinical attachment level, relative horizontal clinical attachment level (RHCAL), gingival margin level (GML), plaque index, and sulcus bleeding index were measured at baseline and 6 months. Radiographic parameters, such as vertical defect depth, horizontal defect depth and defect fill, were measured using cone beam computed tomography, taken at baseline and 6 months. Statistical Analysis Used: The intragroup and intergroup comparisons were done using the paired t-test. Results: The intergroup comparison of mean change in the parameters showed, statistically significant difference in RHCAL (<0.001) and GML (0.014), and no significant difference in other parameters. Conclusions: Within the limitations of the present study, PRF seems to favor soft-tissue healing but has no additional benefit in bone regeneration when used in combination with DFDBA.
Keywords: Allografts, periodontal tissue regeneration, platelet concentrates
|How to cite this article:|
Basireddy A, Prathypaty SK, Yendluri DB, Potharaju SP. Demineralized freeze-dried bone allograft with or without platelet-rich fibrin in the treatment of mandibular Degree II furcation defects: A clinical and cone beam computed tomography study. J Indian Soc Periodontol 2019;23:242-8
|How to cite this URL:|
Basireddy A, Prathypaty SK, Yendluri DB, Potharaju SP. Demineralized freeze-dried bone allograft with or without platelet-rich fibrin in the treatment of mandibular Degree II furcation defects: A clinical and cone beam computed tomography study. J Indian Soc Periodontol [serial online] 2019 [cited 2019 Jul 19];23:242-8. Available from: http://www.jisponline.com/text.asp?2019/23/3/242/253438
| Introduction|| |
Molars with periodontitis involving furcation have a higher rate of periodontal break-down, tooth loss, and risk for further deterioration compared to molars in which furcation is not involved. Regeneration in the inter-radicular area presents one of the greatest challenges in the field of periodontics due to its complex and unique anatomy. Albeit some furcations do exhibit amenable morphology for regeneration, current therapies are unpredictable due to interplay of various factors.
Currently, not a single regenerative material is considered as the gold standard in the treatment of furcation defects. Clinicians continue to seek an “off-the-shelf” material that could replace and/or enhance bone grafts and provide better, more consistent results than current bone scaffolds and matrices. Growth factors are receiving a great deal of attention in the periodontal and craniomaxillofacial fields in recent times. Platelet-rich fibrin (PRF) is a second-generation platelet concentrate, which collects in a fibrin mesh, both platelets and leukocytes in remarkable concentrations as compared to blood, favorable to healing and immunity.
Scientific evidence is currently limited to support the use of biologic agents such as PRF either alone or in association with a graft or guided tissue regeneration for the treatment of furcation defects. A recent systematic review and meta-analysis on the efficacy of platelet concentrates for surgical treatment of periodontal diseases emphasized the need for further randomized studies to investigate if the adjunctive use of platelet concentrates may have benefits for the treatment of furcation defects.
Demineralized freeze-dried bone allograft (DFDBA) remains a viable treatment modality to regenerate the periodontal attachment apparatus. PRF is an immune and platelet concentrate, with several advantages over platelet-rich plasma, such as simplified processing, no biochemical modification, and longer release of growth factors. The aim of the present study was to evaluate the ability of PRF to augment the regenerative effects exerted by DFDBA in the treatment of mandibular Degree II furcation defects.
| Materials and Methods|| |
The present study was a randomized, clinical, double-blinded, and split-mouth study. The patients for the study were selected from the outpatient department. Ethical clearance was obtained from the Institutional Ethics Committee of Government Dental College and Hospital, Hyderabad. The study was conducted from December 2012 to April 2014. Informed consent was taken from the patients. Phase I therapy was performed in 30 patients after initial evaluation, and they were recalled after 4–6 weeks to assess their eligibility for inclusion. Out of 30 patients, 16 patients were excluded due to reduced probing depths after Phase I therapy and reluctance to participate in the study.
Fourteen chronic periodontitis patients within the age group of 30–50 years were considered with certain exclusion and inclusion criteria. Inclusion criteria: presence of mandibular first or second molars with, (1) bilateral buccal or lingual Degree II furcation involvement, according to Hamp's classification, (2) with probing depth (PD) ≥5 mm and horizontal PD ≥3 mm after phase I therapy, (3) with intraoral periapical radiograph (IOPA) showing radiolucency in the furcation area (4) and no endodontic involvement. Exclusion criteria: (1) presence of any systemic disease which is known to affect periodontal wound healing, (2) pregnant or lactating mothers, (3) patients allergic to medications, (4) and smokers or patients using any other forms of tobacco.
A split-mouth design was followed. The 28 defects in 14 patients were allotted either to control (DFDBA alone) or test group (DFDBA and PRF) by coin toss method [Figure 1]. Both the defects in a patient were treated in the same appointment to avoid any crossover effects. Patients and the examiner, who performed all the clinical and radiographic measurements, were blinded to the allotment to reduce any bias.
Clinical parameters, including plaque index (PI), Sulcus bleeding index (SBI), PD, relative vertical clinical attachment level (RVCAL), relative horizontal clinical attachment level (RHCAL), and gingival margin level (GML) were measured at baseline just before surgery. RVCAL, RHCAL, and GML were measured from the lower border of a customized acrylic stent as the reference point, using UNC– 15 and Nabers Q2N probes, as shown in [Figure 2].
|Figure 2: Baseline relative horizontal clinical attachment level measured using Naber's probe in lingual furcation of tooth #46|
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The defect bone fill was assessed using cone beam computed tomography (CBCT), to overcome the shortcomings of intraoral periapical radiographs (IOPAs). The IOPAs are unreliable as a measure of furcation bone fill as they do not delineate the horizontal dimension of the furcation area. For this study, CBCT (compressive sensing (CS) 9300 select system cone beam X-ray technology, Carestream Imaging Company, Rochester, New York) with Field of View of 10 cm × 10 cm, equipped with CS three dimensional (3D) Imaging software was used. The images were obtained in 1 mm slice thickness. Baseline CBCT evaluation was done before the surgery. Radiographic parameters were assessed using the caliper provided with the 3D reconstruction software, with an accuracy of 0.1 mm. Vertical defect depth (VDD) was measured from the furcation fornix to the base of the defect in sagittal view, as shown in [Figure 3]. Horizontal defect depth (HDD) was measured from a tangent drawn connecting the maximum convexities of the mesial and distal roots to the deepest portion of the defect in axial section, as shown in [Figure 4]. All the CBCT scans were taken by a single trained technician. The voltage, current, exposure time, and detection field were kept constant for each patient at both the times of exposure. Duplicate values were always taken, and the final values were a mean of the duplicate values. The morphology of furcation defect in CBCT is depicted in [Figure 5].
|Figure 3: Vertical defect depth was measured from the furcation fornix to the base of the defect in the sagittal view, with the calipers available in the cone beam computed tomography software|
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|Figure 4: Horizontal defect depth was measured from the maximum convexities of the mesial and distal roots to the deepest portion of the defect in axial section, with the calipers provided in the cone beam computed tomography software|
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|Figure 5: Cone beam computed tomography image showing the morphology of furcation defect irrespective to lingual furcation of 46 in axial, coronal, and sagittal sections|
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The area of interest was anesthetized using 2% lignocaine solution containing adrenaline in the ratio of 1:80,000. Full-thickness mucoperiosteal flaps were raised after giving sulcular and interdental incisions. Debridement was done using area-specific curettes and ultrasonic instruments. The defect dimensions were verified after debridement to check if they met the inclusion criteria. In the control group, the furcation defect was filled with DFDBA (<500 microns granules from Tata Memorial Tissue Bank, Mumbai). The mucoperiosteal flaps were repositioned using direct interrupted sutures with 3-0 surgical silk.
In the test group, after the debridement of the defect, 5 ml of venous blood was drawn from the patient's ante-cubital vein and immediately centrifuged (REMI 8C centrifuge) without the addition of any anticoagulants at 3000 rpm for 10 min. The PRF clot was separated from the underlying red blood cells (RBCs) with a sterile tweezers or scissors and compressed using sterile gauze to remove the serum and obtain a PRF membrane. Clot was compressed in the present study to make it easier to manipulate along with bone graft; however, the serum expressed from the clot was used to wet the graft. The portion of PRF clot toward the RBCs was then mixed with DFDBA and placed into the furcation defect, as shown in [Figure 6]. Mucoperiosteal flaps were repositioned. The patients were prescribed 500 mg amoxicillin thrice daily for 5 days and a combination of diclofenac and paracetamol twice daily for 3 days. Chlorhexidine gluconate mouthwash was prescribed twice daily for 2 weeks.
|Figure 6: (a) Placement of demineralized freeze-dried bone allograft alone in furcation defect of tooth #36 (b) Placement of demineralized freeze-dried bone allograft and platelet-rich fibrin combination in furcation defect of tooth # 46|
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The patients were evaluated at regular intervals of 1 week, 2 weeks, 1 month, 3 months, and 6 months postoperatively. At all appointments, oral hygiene instructions were reinforced, and any adverse events reported were noted. [Figure 7] shows the follow-up chart. At 6 months, the clinical and radiographic assessments were repeated.
|Figure 7: Flowchart showing follow-up in the study. SRP – Scaling and root planing, OHI – Oral hygiene instructions, CBCT – Cone beam computed tomography scan, PI – Plaque index, SBI – Sulcus bleeding index, PD – Probing depth, RHCAL – Relative horizontal clinical attachment level, RVCAL – Relative vertical clinical attachment level, VDD – Vertical defect depth, HDD – Horizontal defect depth|
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The clinical and radiographic parameters measured at baseline and 6 months were analyzed using SPSS 16.0; SPSS Inc., Chicago, IL, USA. The intragroup comparison of baseline and 6 months values within test and control groups and intergroup comparison were done using the paired t-test. P < 0.05 was considered to be statistically significant.
| Results|| |
At baseline, the parameters of the test and control groups did not show any statistically significant difference. The patients did not report any adverse events, and good healing was observed in all the surgical sites. The preoperative and postoperative CBCT images in axial, coronal, and sagittal sections are depicted in [Figure 8], [Figure 9], [Figure 10].
|Figure 8: Test group: Axial section – Preoperative and 6 months postoperative cone beam computed tomography images of 46 lingual furcation|
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|Figure 9: Test group: Coronal section – Preoperative and 6 months postoperative cone beam computed tomography images of 46 lingual furcation|
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|Figure 10: Test group: Sagittal section – Preoperative and 6 months postoperative cone beam computed tomography images of 46 lingual furcation defect|
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The intragroup comparison of clinical and radiographic parameters at baseline and 6 months in the test group showed statistically significant difference in mean PD, RVCAL, RVCAL, VDD, and HDD. There was no statistically significant difference in mean GML from baseline to 6 months in the test group. The mean and P values for the test group are mentioned in [Table 1].
|Table 1: Intragroup comparison of mean values of all parameters in the test group recorded at baseline and 6 months, done using the paired t-test|
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The intragroup comparison of all parameters at baseline and 6 months in control group showed statistically significant difference in the mean PD, RVCAL, RHCAL, GML, VDD, and HDD. The mean and P values for the control group are mentioned in [Table 2].
|Table 2: Intragroup comparison of mean values of all parameters in control group recorded at baseline and 6 months, done using the paired t-test|
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The change in VDD and HDD are depicted in % defect resolution using the following formula:
The intergroup comparison of the difference in the mean change of PD, RVCAL, % change in VDD and HDD was not statistically significant. However, the difference in mean change of RHCAL (<0.001) and GML (0.014) was statistically significant, as depicted in [Table 3].
|Table 3: Comparison of change in parameters from baseline to 6 months between test and control group done using the paired t-test|
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The comparison of mean PI and SBI scores recorded at 4–6 weeks before surgery and at 6 months is summarized in [Table 4]. The indices represent full mouth plaque scores and gingival inflammation levels as observed during the course of the study.
|Table 4: Comparison of plaque index and sulcus bleeding index at baseline and 6 months|
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| Discussion|| |
The purpose of the platelet concentrate is to connect various elements in the wound healing site such as matrix, cells, and accelerate angiogenesis. Once mixed with platelet concentrates, the bone graft becomes more cell-migration friendly and growth factors in the PRF will stimulate proliferation and differentiation of cells in the surrounding milieu.
DFDBA is an osteoinductive and osteoconductive bone graft and has been the regenerative material of choice whenever autografts are not viable. Apart from its easy availability and osteogenic potential, many clinical studies have reported substantial bone fill with its use. This study was aimed to determine whether the addition of PRF could enhance the regenerative potential of DFDBA in the treatment of furcation defects. The test group when compared to control group showed statistically significant difference in RHCAL gain (<0.001) and GML change (0.014). The other clinical and radiographic parameters did not show statistically significant difference. The lack of difference in the clinical and radiographic parameters can be attributed to the use of DFDBA in both the groups, which may have overcome the effect of PRF. The osteogenic and osteoinductive potential of DFDBA may vary depending on the donor characteristics, processing procedures, and bone graft batch. Strict standards to monitor the inductive properties of each batch of grafts by tissue banks may lead to more reliable results. No direct comparisons can be made with any other study since this is the first study comparing the use of DFDBA in combination with PRF and DFDBA alone in the treatment of furcation defects.
The changes in the PD and CAL of control group fall within the range concluded in a systematic review by Reynolds et al. In the control group of present study, mean changes in PD, RHCAL, and RVCAL were 2.36, 1.79, and 1.5 mm, respectively.
CBCT was used in this study to overcome the shortcomings of two-dimensional imaging and also to visualize the horizontal component of the furcation. Grimard et al. compared cone beam volumetric tomography (CBVT) and periapical radiographs to intrasurgical measurements and suggested CBVT to be a substitute for direct surgical measurements of bony changes. The bone fill observed in the control group was in agreement with the bone fill achieved in the DFDBA (obtained from American Red Cross, Washington) group in a study by Lyons et al. Lyons et al. used direct surgical measurements for the bone fill assessment. In view of the decreased radiation risk with CBCT and the access to the horizontal component of the furcation, future studies on furcations should include CBCT evaluation when no direct bone measurements are being made.
In a study by Sharma et al., the bone fill was around 50% in the PRF + open flap debridement (OFD) group while in the present study the change in VDD was 46% in the test and 42% in the control group. Only the changes in the VDD can be compared between the two studies since in the study by Sharma et al. IOPAs have been utilized which do not allow the measurement of HDD. The highly significant results obtained in the study by Sharma et al. regarding radiographic parameters may due to comparison with OFD, which is cleary inferior to any regenerative procedure. Alternatively, the results can be attributed to the discrepancies in two-dimensional radiography. In the present study, the comparison of the test group with a positive control may have yielded the nonsignificant results.
In furcation defects, the horizontal parameters (i.e., RHCAL and HDD) are directly related to the prognosis of the tooth. In the present study, the mean change in RHCAL from baseline to 6 months in test and control group was 4.57 ± 1.697 and 1.50 ± 1.092 mm, respectively. The difference between the two groups was highly significant. However, the mean percentage change in HDD in test and control groups was 38.20 ± 12.57 and 37.99 ± 13.56 for the test and control group, respectively. The difference between the two groups was not statistically significant. Despite the many factors that affect the reproducibility of measurement of CAL, changes in CAL usually follow the changes in bone.
The discrepancy in the RHCAL and HDD changes in the present study can be attributed to the reformation of the supracrestal apparatus, which offers great resistance to probe penetration and also the complexity of the furcation anatomy. The excellent soft-tissue healing properties of PRF may have played a role in this discrepancy. The accelerated healing may be a result of the presence of a fibrin clot, which stabilizes the early wound-healing matrix. Mansouri et al. also reported reduced probe penetration when plasma rich in growth factors was used in combination with bovine porous bone mineral when compared to the control group.
In the present study, the test group showed less changes in the gingival margin (0.21 ± 0.426) compared to the control group (0.79 ± 0.579). In a study by Sharma et al., similar changes in GML were observed in the PRF group (0.344 ± 0.086) as compared to the OFD group (0.756 ± 0.115). These changes in the test groups can be attributed to soft-tissue healing properties of PRF. PRF consists of a fibrin matrix with the incorporation of platelets, leukocytes, cytokines, and circulating stem cells. Slow fibrin polymerization during PRF processing leads to the intrinsic incorporation of platelet cytokines and glycan chains in the fibrin meshes. PRF also exhibits high number of leukocytes. During healing, leukocytes seem to have a positive influence on growth factor release and matrix remodeling., PRF is an optimal amalgamation of properties favoring migration of endothelial cells and fibroblasts. Such a mechanism might explain the observed clinical improvement in the test group.
In a study by Bansal et al., it was observed that PRF when used in combination with DFDBA, did not have any additional beneficial effect on defect fill and defect resolution in the treatment of periodontal intrabony defects. However, various in vitro studies have shown a beneficial effect of PRF on bone healing. Even in the present study, there was no additional favorable effect of PRF on defect depth reduction and bone fill.
Furcation defect anatomy and location of the defect itself play a role in determining the success of regenerative therapy. Location of the fornix coronal to the interproximal alveolar crest, and a wide furcation entrance has negative influence on the outcome parameters. Vertical or horizontal furcation defect depth of >5 mm respond less favorably to regenerative therapy. In the present study, furcation defects with greater initial defect dimensions responded less favorably. This may partially explains the non-significant results.
One of the limitations of the study is the short-term follow up. Long-term follow-up studies need to be conducted to determine the longevity of the clinical improvements observed with the addition of PRF. Another limitation is the inclusion of both first and second molars showing buccal or lingual furcation involvement. The root morphology and furcation access at the varying defect sites may affect surgical management. Due to the limited sample size, the influence of defect site location on treatment outcomes could not be concluded.
| Conclusions|| |
From a clinical point of view, the complete elimination of interradicular defect is the most desirable outcome. However, none of the defects in the present study showed complete closure. This implies that both the regenerative materials show partial regeneration. The prognosis and survival of the teeth with such partial regeneration needs to be determined with long-term follow up. The addition of PRF to DFDBA seems to favor soft-tissue healing but did not affect the bone fill.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10]
[Table 1], [Table 2], [Table 3], [Table 4]