Crevicular Fluid Growth Factors Release Profile Following the Use of Platelet‐Rich Fibrin and Plasma Rich Growth Factors in Treating Periodontal Intrabony Defects: A Randomized Clinical Trial

Background: The open, usually contaminated nature of periodontal defects could negatively affect availability and activity of platelet concentrate–suggested growth factors (GF). The aim of this study is to test this hypothesis and investigate concentrations of: 1) vascular endothelial growth factor (VEGF) and 2) platelet‐derived growth factor (PDGF‐BB) in gingival crevicular fluid (GCF) from localized intrabony defects treated with platelets rich in growth factors (PRGF) or platelet‐rich fibrin (PRF) compared with a control xenograft defect filling. Methods: Thirty non‐smoking patients suffering severe chronic periodontitis were allocated to this randomized, prospective, single‐masked trial. Each patient had one interproximal defect randomly distributed to: 1) group 1: bone‐substitute grafting control (n = 10); 2) group 2: experimental PRGF (n = 10); or 3) group 3: PRF (n = 10). Clinical parameters were measured at baseline and 6 and 9 months following therapy. GCF samples were obtained on days 1, 3, 7, 14, 21, and 30 after therapy for evaluation of VEGF and PDGF‐BB levels. Results: On days 1, 3, and 7 following surgery, mean levels of VEGF and PDGF‐BB at sites treated with PRGF and PRF were not significantly different versus the control. Levels of PDGF‐BB and VEGF were higher in the PRGF‐treated group, but differences were not significant. Growth factor levels decreased significantly in samples collected on days 14, 21, and 30 with non‐significant differences among the three groups. No significant clinical differences were reported among the three groups during the two observation periods (early period: days 1, 3, and 7; and later period: days 14, 21, and 30). Conclusions: Within the limits of the present study, it can be concluded that PRF and PRGF platelet concentrate failed to augment clinical effects achieved with the xenograft alone in treating intrabony defects. Periodontal defects could not retain extraphysiologic levels of GF suggested to be associated with platelet concentrate.     

Advantages of Autologous Platelet‐Rich Fibrin Membrane on Gingival Crevicular Fluid Growth Factor Levels and Periodontal Healing: A Randomized Split‐Mouth Clinical Study

Background: This study evaluates contributions of platelet‐rich fibrin (PRF) combined with conventional flap surgery on growth factor levels in gingival crevicular fluid (GCF) and periodontal healing. Methods: Twenty‐six patients (52 sites) with chronic periodontitis were treated either with autologous PRF with open flap debridement (OFD+PRF) or OFD alone. Growth factor levels in GCF at baseline and 2, 4, and 6 weeks after surgery were analyzed, and clinical parameters such as probing depth (PD), relative clinical attachment level (rCAL), and gingival margin level (GML) at baseline and 9 months after surgery were measured. Results: Mean PD reduction and rCAL gain were significantly greater in OFD+PRF sites than in OFD sites. Mean GML change was ?0.38 + 0.10 mm in OFD sites and 0.11 + 0.08 mm in the test group; difference between the two groups was statistically significant (P <0.05). Both groups demonstrated increased expression levels of fibroblast growth factor‐2, transforming growth factor‐β1, and platelet‐derived growth factor‐BB at 2 weeks compared with baseline, followed by reductions at 4 and 6 weeks. The OFD+PRF group showed significantly higher growth factor levels compared with the OFD group at 2 and 4 weeks. Conclusion: PRF membrane combined with OFD provides significantly higher GCF concentrations of angiogenic biomarkers for ≈2 to 4 weeks and better periodontal healing in terms of conventional flap sites.     

Titanium‐prepared platelet‐rich fibrin provides advantages on periodontal healing: A randomized split‐mouth clinical study

1 Background

The aim of this study to evaluate the contributions of titanium‐prepared platelet‐rich fibrin (T‐PRF) combined with open flap debridement (OFD) on biological markers in gingival crevicular fluid (GCF)and periodontal outcomes.

2 Methods

Twenty‐nine participants with chronic periodontitis were treated either with autologous T‐PRF+OFD or OFD alone. GCF growth factor levels and relative receptor activator nuclear factor kappa‐B/osteoprotegerin (RANKL/OPG) ratio at baseline and 2, 4, and 6 weeks postoperatively were analyzed, and clinical parameters such as probing depth (PD), relative attachment level (RAL) and gingival margin level (GML) at baseline and 9 months after surgery were compared.

3 Results

The mean PD reduction, RAL gain, and GML change were significantly greater in the OFD+T‐PRF sites than in the OFD sites (P = 0.033, P = 0.029, and P = 0.026, respectively). Both groups demonstrated increased growth factor levels at week 2 compared with baseline, followed by reductions at weeks 4 and 6. GCF growth factor levels in the test group were seen at higher concentrations with respect to control group until 6 weeks post‐surgery. During this 6‐week period, relative RANKL/OPG ratio was found significantly lower in the OFD+T‐PRF group compared to the OFD group(P < 0.05).

4 Conclusions

Using T‐PRF membrane combined with OFD provided significantly higher concentrations of growth factors and lower RANKL/OPG ratio in GCF for approximately 4 to 6 weeks, and improved periodontal healing compared to conventional flap sites.     

Platelet‐Derived Growth Factor Promotes Periodontal Regeneration in Localized Osseous Defects: 36‐Month Extension Results From a Randomized,Controlled, Double‐Masked Clinical Trial

Background: Recombinant human platelet‐derived growth factor (rhPDGF) is safe and effective for the treatment of periodontal defects in short‐term studies up to 6 months in duration. We now provide results from a 36‐month extension study of a multicenter, randomized, controlled clinical trial evaluating the effect and long‐term stability of PDGF‐BB treatment in patients with localized severe periodontal osseous defects. Methods: A total of 135 participants were enrolled from six clinical centers for an extension trial. Eighty‐three individuals completed the study at 36 months and were included in the analysis. The study investigated the local application of β‐tricalcium phosphate scaffold matrix with or without two different dose levels of PDGF (0.3 or 1.0 mg/mL PDGF‐BB) in patients possessing one localized periodontal osseous defect. Composite analysis for clinical and radiographic evidence of treatment success was defined as percentage of cases with clinical attachment level (CAL) ≥2.7 mm and linear bone growth (LBG) ≥1.1 mm. Results: The participants exceeding this composite outcome benchmark in the 0.3 mg/mL rhPDGF‐BB group went from 62.2% at 12 months, 75.9% at 24 months, to 87.0% at 36 months compared with 39.5%, 48.3%, and 53.8%, respectively, in the scaffold control group at these same time points (P <0.05). Although there were no significant increases in CAL and LBG at 36 months among all groups, there were continued increases in CAL gain, LBG, and percentage bone fill over time, suggesting overall stability of the regenerative response. Conclusion: PDGF‐BB in a synthetic scaffold matrix promotes long‐term stable clinical and radiographic improvements as measured by composite outcomes for CAL gain and LBG for patients possessing localized periodontal defects ( ClinicalTrials.gov no. CT01530126).     

Doxycycline‐Loaded β‐Tricalcium Phosphate Release Following EDTA Root Surface Etching Improved the Clinical Outcomes in Chronic Periodontitis: An In Vivo Study

Background: The main objective of the present study is to quantify doxycycline (DOX) release from β‐tricalcium phosphate (β‐TCP) after EDTA root surface treatment. Methods: Thirty systemically healthy patients with ≥1 paired contralateral interproximal intrabony defect ≥4 mm deep along with an interproximal probing depth ≥6 mm and clinical attachment level ≥4 mm were randomized into two groups. Group 1 (G1) consisted of sites treated with open flap debridement followed by placement of DOX blended with β‐TCP (DOX‐β‐TCP), whereas group 2 (G2) sites were treated with flap surgery followed by the placement of DOX blended with β‐TCP after EDTA etching of the exposed root surfaces (DOX‐β‐TCP + EDTA). Samples of gingival crevicular fluid (GCF) were obtained 1, 3, 7, 14, and 21 days after surgery. Quantitative measurements of DOX were taken with high‐performance liquid chromatography. Clinical evaluation and follow‐up for 6 months were performed. Results: At 21 days, the DOX‐β‐TCP + EDTA–treated group showed a 194.7 µg/mL value. The DOX‐β‐TCP + EDTA–treated group retained more DOX during the periods of 3, 7, 10, 14, and 21 days than the DOX‐β‐TCP–treated group. Six months after therapy, DOX‐β‐TCP + EDTA–treated sites showed more significant clinical improvements compared to DOX‐β‐TCP–treated sites (P ≤ 0.05). Conclusions: EDTA root surface etching enhances DOX availability in the GCF following its release from β‐TCP as a drug carrier.     

Platelet‐Rich Fibrin With 1% Metformin for the Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial

Background: Platelet‐rich fibrin (PRF) is a second‐generation platelet concentrate that releases various growth factors that promote tissue regeneration. Metformin (MF), a member of the biguanide group, has been shown to facilitate osteoblast differentiation and thus may exhibit a favorable effect on alveolar bone. The current study is designed to evaluate the efficacy of open‐flap debridement (OFD) combined with PRF, 1% MF gel, and PRF + 1% MF gel in the treatment of intrabony defects (IBDs) in patients with chronic periodontitis (CP). Methods: One hundred twenty patients with single defects were categorized into four treatment groups: OFD alone, OFD with PRF, OFD with 1% MF, and OFD with PRF plus 1% MF. Clinical parameters such as site‐specific plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), relative attachment level (RAL), and gingival marginal level (GML) were recorded at baseline (before surgery) and 9 months postoperatively. Percentage radiographic IBD depth reduction was evaluated using computer‐aided software at baseline and 9 months. Results: PRF, 1% MF, and PRF + 1% MF groups showed significantly more PD reduction and RAL gain than the OFD‐only group. Mean PD reduction and mean RAL gain were found to be greater in the PRF + 1% MF group compared to just PRF or MF at 9 months. Furthermore, PRF + 1% MF group sites showed a significantly greater percentage of radiographic defect depth reduction (52.65% ± 0.031%) compared to MF (48.69% ± 0.026%), PRF (48% ± 0.029%), and OFD alone (9.14% ± 0.04%) at 9 months. Conclusion: The PRF + 1% MF group showed greater improvements in clinical parameters, with greater percentage radiographic defect depth reduction compared to MF, PRF, or OFD alone in treatment of IBDs in patients with CP.     

Platelet‐Rich Fibrin With 1.2% Rosuvastatin for Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial

Background: Regenerative periodontal therapy encompasses use of various bioactive agents that are not only inflammomodulatory but also osteoclast‐inhibitory or, rather, osteostimulative. Hypolipidemic statin drugs, particularly rosuvastatin (RSV), are known to be associated with alveolar bone formation and periodontal improvements. Platelet analogs such as platelet‐rich fibrin (PRF), being rich sources of growth factors, have also come into widespread periodontal regenerative use. The aim of this study is to evaluate and compare efficacy of open flap debridement (OFD) with or without PRF or PRF + 1.2% RSV gel in treatment of intrabony defects (IBDs) in patients with chronic periodontitis (CP). Methods: Ninety individuals with a total of 90 IBDs were randomly assigned to one of three treatment groups: 1) OFD alone; 2) OFD + PRF; and 3) OFD + PRF + 1.2% RSV gel placement. Measurements recorded at baseline and 9 months after surgery were: 1) plaque index (PI); 2) modified sulcus bleeding index (mSBI); 3) probing depth (PD); 4) clinical attachment level (CAL); and 5) IBD depth. Results: Significant PI and mSBI reductions were observed in all three groups. PRF placement significantly enhanced improvements in periodontal parameters compared with OFD alone. Addition of 1.2% RSV gel to PRF resulted in significantly greater CAL gain and PD and IBD depth reductions over 9 months compared with other groups. Conclusion: OFD with RSV (1.2%) and PRF results in significantly greater periodontal benefits compared with OFD alone or with PRF.     

Mixed Nano/Micro‐Sized Calcium Phosphate Composite and EDTA Root Surface Etching Improve Availability of Graft Material in Intrabony Defects: An In Vivo Scanning Electron Microscopy Evaluation

Background: The use of nanoparticles of graft materials may lead to breakthrough applications for periodontal regeneration. However, due to their small particle size, nanoparticles may be eliminated from periodontal defects by phagocytosis. In an attempt to improve nanoparticle retention in periodontal defects, the present in vivo study uses scanning electron microscopy (SEM) to evaluate the potential of micrograft particles of β‐tricalcium phosphate (β‐TCP) to enhance the binding and retention of nanoparticles of hydroxyapatite (nHA) on EDTA‐treated and non‐treated root surfaces in periodontal defects after 14 days of healing. Methods: Sixty patients having at least two hopeless periodontally affected teeth designated for extraction were randomly divided into four treatment groups (15 patients per group). Patients in group 1 had selected periodontal intrabony defects grafted with nHA of particle size 10 to 100 nm. Patients in group 2 were treated in a similar manner but had the affected roots etched for 2 minutes with a neutral 24% EDTA gel before grafting of the associated vertical defects with nHA. Patients in group 3 had the selected intrabony defects grafted with a composite graft consisting of equal volumes of nHA and β‐TCP (particle size 63 to 150 nm). Patients in group 4 were treated as in group 3 but the affected roots were etched with neutral 24% EDTA as in group 2. For each of the four groups, one tooth was extracted immediately, and the second tooth was extracted after 14 days of healing for SEM evaluation. Results: Fourteen days after surgery, all group 1 samples were devoid of any nanoparticles adherent to the root surfaces. Group 2 showed root surface areas 44.7% covered by a single layer of clot‐blended grafted particles 14 days following graft application. After 14 days, group 3 samples appeared to retain fibrin strands devoid of grafted particles. Immediately extracted root samples of group 4 had adherent graft particles that covered a considerable area of the root surfaces (88.6%). Grafted particles appeared to cover all samples in a multilayered pattern. After 14 days, the group 4 extracted samples showed multilayered fibrin‐covered nano/micro‐sized graft particles adherent to the root surfaces (78.5%). Conclusion: The use of a composite graft consisting of nHA and microsized β‐TCP after root surface treatment with 24% EDTA may be a suitable method to improve nHA retention in periodontal defects with subsequent graft bioreactivity.     

Intrabony Defects,Open‐Flap Debridement,and Decortication: A Randomized Clinical Trial

Background: Intramarrow penetration (IMP) is often incorporated in regenerative periodontal surgical procedures. However, the actual benefits of adding IMP to such a procedure remain undocumented. The purpose of this randomized controlled trial was to investigate the contribution of IMP to the outcomes of open‐flap debridement (OFD) treatment of intrabony defects. Methods: Forty‐two chronic periodontitis patients, each contributing a 2‐wall, 3‐wall, or combined 2‐ to 3‐wall intrabony defect, were treated. Sites were randomly assigned into one of two groups: control (OFD alone) or test (OFD + IMP). Papilla preservation flaps were raised, and defects were thoroughly debrided. In the control group, complete primary closure of flaps was ensured after debridement. In the test group, IMP was performed before flap closure, using a round bur to penetrate the cortical defect wall. Clinical and radiographic parameters were assessed at baseline and 12 months after treatment. Results: At baseline, there were no statistically significant differences between groups. At 12 months, both groups experienced significant improvements, in terms of probing depth reduction, clinical attachment level (CAL) gain, and bone level (clinical and radiographic). The test group experienced significantly greater clinical bone gain (3.07 ± 1.74 mm) and prevalence of CAL gain ≥2 mm (93% of sites) compared with the control group (1.76 ± 2.71 mm, P <0.03; 62%, P = 0.024). The test treatment benefits were particularly evident in mandibular sites, in which OFD + IMP doubled the radiographic bone gain obtained by OFD alone. Conclusion: Addition of IMP to an OFD procedure used to treat intrabony defects results in statistically and clinically significant enhancement of both clinical and radiographic outcomes.     

Platelet‐Rich Fibrin Combined With 1.2% Atorvastatin for Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial

Background: Platelet‐rich fibrin (PRF), a second‐generation platelet concentrate, and atorvastatin (ATV), a potent member of the statin group, are known to promote tissue regeneration. The current study is designed to evaluate combined efficacy of PRF and 1.2% ATV gel with open flap debridement (OFD) in treatment of intrabony defects (IBDs) in individuals with chronic periodontitis (CP). Methods: Ninety‐six individuals with single defects were categorized into three groups: 1) OFD with PRF; 2) OFD with PRF + 1.2% ATV; and 3) OFD alone. Clinical parameters: 1) site‐specific plaque index; 2) modified sulcus bleeding index; 3) probing depth (PD); 4) relative clinical attachment level (rCAL); and 5) gingival marginal level were recorded at baseline before surgery and 9 months postoperatively. Percentage radiographic IBD depth reduction was evaluated at baseline and 9 months. Results: PRF + 1.2% ATV and PRF alone showed significantly greater PD reduction and rCAL gain compared with OFD alone at 9 months. Furthermore, PRF + 1.2% ATV showed a similar percentage radiographic defect depth reduction (50.96% ± 4.88%) compared with PRF alone (47.91% ± 4.79%), and a greater reduction compared with OFD alone (5.54% ± 1.71%) at 9 months. Conclusions: PRF + 1.2% ATV showed similar improvements in clinical parameters with a greater percentage radiographic defect depth reduction compared with PRF alone in treatment of IBDs in individuals with CP. Thus, 1.2% ATV failed to augment the regenerative potential of PRF alone in periodontal IBDs.     

Nano‐Sized Calcium Phosphate Particles for Periodontal Gene Therapy

Background: Growth factors such as platelet‐derived growth factor (PDGF) have significantly enhanced periodontal therapy outcomes with a high degree of variability, mostly due to the lack of continual supply for a required period of time. One method to overcome this barrier is gene therapy. The aim of this in vitro study is to evaluate PDGF‐B gene delivery in fibroblasts using nano‐sized calcium phosphate particles (NCaPP) as vectors. Methods: NCaPP incorporating green fluorescent protein (NCaPP‐GFP) and PDGF‐B (NCaPP‐PDGF‐B) plasmids were synthesized using an established precipitation system and characterized using transmission electron microscopy and 1.2% agarose gel electrophoresis. Biocompatibility and transfection of the nanoplexes in fibroblasts were evaluated using cytotoxicity assay and florescence microscopy, respectively. Polymerase chain reaction and enzyme‐linked immunosorbent assay were performed to evaluate PDGF‐B transfection after different time points of treatments, and the functionality of PDGF‐B transfection was evaluated using the cell proliferation assay. Results: Synthesized NCaPP nanoplexes incorporating the genes of GFP and PDGF‐B were spherical in shape and measured about 30 to 50 nm in diameter. Gel electrophoresis confirmed DNA incorporation and stability within the nanoplexes, and 3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium reagent assay demonstrated their biocompatibility in fibroblasts. In vitro transfection studies revealed a higher and longer lasting transfection after NCaPP‐PDGF‐B treatment, which lasted up to 96 hours. Significantly enhanced fibroblast proliferation observed in NCaPP‐PDGF‐B–treated cells confirmed the functionality of these nanoplexes. Conclusion: NCaPP demonstrated higher levels of biocompatibility and efficiently transfected PDGF plasmids into fibroblasts under described in vitro conditions.     

Enamel Matrix Derivative,Alone or Associated With a Synthetic Bone Substitute,in the Treatment of 1‐ to 2‐Wall Periodontal Defects

Background: In this study, we compare the effects of enamel matrix derivative (EMD) associated with a hydroxyapatite and β‐tricalcium phosphate (HA/β‐TCP) implant to EMD alone and to open‐flap debridement (OFD) when surgically treating 1‐ to 2‐wall intrabony defects. Methods: Thirty‐four patients, exhibiting ≥3 intraosseous defects in different quadrants, were each treated by OFD, EMD, or EMD + HA/β‐TCP in each defect. At baseline and 12 and 24 months, a complete clinical and radiographic examination was done. Pre‐therapy and post‐therapy clinical (probing depth [PD], clinical attachment level [CAL], and gingival recession [GR]) and radiographic (defect bone level [DBL] and radiographic bone gain [RBG]) parameters for the different treatments were compared. Results: After 12 and 24 months, almost all the clinical and radiographic parameters showed significant changes from baseline within each group (P <0.001). Differences in PD, CAL, and DBL scores were also seen among the three groups at the 12‐ and 24‐month visits (P <0.001). At 12 and 24 months after treatment, the EMD + HA/β‐TCP group showed significantly greater PD reduction (4.00 ± 0.42 mm; 4.25 ± 0.63 mm), CAL gain (3.47 ± 0.65 mm; 3.63 ± 0.91 mm), and RBG (3.17 ± 0.69 mm; 3.35 ± 0.80 mm) and less GR increase (0.56 ± 0.37 mm; 0.63 ± 0.42 mm) compared with the OFD and EMD groups (P <0.05). Conclusion: Our data support the hypothesis that the adjunct of an HA/β‐TCP composite implant with EMD may improve the clinical and radiographic outcomes of the surgical treatment of unfavorable intrabony defects.     

Influence of Endodontic Treatment in the Post‐Surgical Healing of Human Class II Furcation Defects

Background: Treatment of molar furcation defects remains a considerable challenge in clinical practice. The degree of success in the management of furcation involvement is highly variable and related to the baseline clinical status of these defects. The identification of clinical parameters influential to the treatment outcomes is critical to optimize the results of surgical periodontal therapy. The impact of the endodontic treatment (ET) of the tooth on the healing potential of the periodontium is controversial. Therefore, the objective of this study is to evaluate the clinical response of buccal Class II furcation defects to open‐flap debridement (OFD) and to determine the influence of ET in the clinical outcomes of therapy. Methods: Sixty patients were divided into two treatment groups (n = 30): 1) OFD; and 2) OFD in endodontically treated teeth (OFD + ET). The clinical variables evaluated were plaque (full‐mouth plaque score), bleeding on probing, gingival recession, probing depth (PD), and vertical (VAL) and horizontal (HAL) attachment levels. Reevaluation was performed 12 months after the surgical procedures. Results: Both treatments resulted in improvements in all the clinical variables evaluated. Postoperative measurements from OFD‐treated and OFD + ET–treated sites showed, respectively, 1.2 ± 1.2 and 1.3 ± 1.3 mm reduction in PD, 0.6 ± 0.8 and 0.7 ± 0.6 mm VAL gains, and 0.7 ± 1.1 and 0.8 ± 1.6 mm HAL gains. No significant differences were found between the groups. Conclusion: The present findings demonstrate that adequate endodontic therapy performed ≥6 months before surgical treatment does not significantly influence the clinical parameters of healing of human mandibular buccal Class II furcation defects.     

Platelet‐Rich Fibrin Combined With a Porous Hydroxyapatite Graft for the Treatment of 3‐Wall Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial

Background: Porous hydroxyapatite (HA) bone grafting material has been used to fill periodontal intrabony defects (IBDs), resulting in clinically acceptable responses. Platelet‐rich fibrin (PRF) is a leukocyte and platelet preparation that concentrates various polypeptide growth factors and, therefore, has the potential for use as regenerative treatment for periodontal defects. The present study aims to explore the clinical and radiographic effectiveness of autologous PRF versus PRF + HA in treatment of IBDs in patients with chronic periodontitis. Methods: Ninety IBDs were treated with autologous PRF with open‐flap debridement (OFD), PRF + HA with OFD, or OFD (controls) alone. Clinical and radiologic parameters, including probing depth (PD), clinical attachment level (CAL), IBD depth, and percentage defect fill were recorded at baseline and 9 months postoperatively. Results: Mean PD reduction was greater in PRF (3.90 ± 1.09 mm) and PRF + HA (4.27 ± 0.98 mm) groups than the control group (2.97 ± 0.93 mm), and mean CAL gain was greater in PRF (3.03 ± 1.16 mm) and PRF + HA (3.67 ± 1.03 mm) compared to controls (2.67 ± 1.09 mm). Furthermore, significantly greater percentage of mean bone fill was found in the PRF (56.46% ± 9.26%) and PRF + HA (63.39% ± 16.52%) groups compared to controls (15.96% ± 13.91%). Conclusions: Treatment of IBD with PRF results in significant improvements of clinical parameters compared to baseline. When added to PRF, HA increases the regenerative effects observed with PRF in the treatment of 3‐wall IBDs.     

The combination of purified recombinant human platelet-derived growth factor-BB and equine particulate bone graft for periodontal regeneration

Background: The objective of this study is to evaluate the potential for periodontal regeneration of a critical‐sized defect with the application of recombinant human platelet‐derived growth factor (rhPDGF‐BB) combined with either a particulate equine or a β‐tricalcium phosphate (β‐TCP) matrix. Methods: Critical‐sized intrabony 2‐wall defects were created bilaterally on the distal surface of the second premolar and the mesial surface of the first molar in nine hounds. Twelve defects received rhPDGF‐BB/equine treatment, 12 defects received rhPDGF‐BB/β‐TCP treatment, and the remaining 12 sites served as sham‐surgery controls. The animals were sacrificed after a 10‐week healing period. Results: Clinical healing was uneventful without obvious signs of overt gingival inflammation. Histologic and histomorphometric analyses revealed statistically that there were differences among the three groups in terms of new bone formation (P <0.001). The amount of test material for both rhPDGF‐BB/equine and rhPDGF‐BB/β‐TCP groups was comparable, but the amount of newly formed bone was significantly higher (P <0.01) in favor of the rhPDGF‐BB/equine group. The amount of new cementum formed for the rhPDGF‐BB/equine group (4.8 ± 1.3 mm) was significantly higher (P =0.001) than the sham‐surgery control group (1.7 ± 1.9 mm). Conclusion: Both rhPDGF‐BB/equine and rhPDGF‐BB/β‐TCP have the potential to support the regeneration of the periodontal attachment apparatus.     

Mandibular Class II Furcation Defect Treatment: Effects of the Addition of Platelet Concentrates to Open Flap: A Systematic Review and Meta‐Analysis of Randomized Clinical Trials

Background: To improve the efficacy and outcomes of regenerative therapy for furcation defects, the use of platelet concentrates (PCs) in addition to open flap debridement (OFD) has been investigated. The aim of this systematic review is to evaluate whether mandibular Class II furcation defects treated with the addition of PC to OFD heal with a significant improvement in the following: 1) horizontal clinical attachment level (HCAL); 2) vertical clinical attachment level (VCAL); 3) probing depth (PD); and 4) level of gingival margin (LGM). Methods: Electronic databases (MEDLINE, EBSCO Library, Cochrane Database of Systematic Reviews, and SCOPUS) were searched for randomized clinical trials to address the use of PCs in combination with OFD compared with a control group without PCs for the treatment of mandibular Class II furcation defects in humans and to provide data on the above reported outcome measures. The results of selected studies were converted to mean difference and standard error and interpolated using the inverse of variance test. Heterogeneity was investigated using both the Higgins index and the Q test. Results: Of 254 articles screened, only 11 were read in full text, and three of these were included in the meta‐analysis. The addition of PCs to OFD revealed a small improvement in the following: 1) HCAL (mean difference, 1.36 mm; 95% confidence interval [CI] = 1.07 to 1.65); 2) VCAL (mean difference, 1.54 mm; 95% CI = 1.23 to 1.85); and 3) PD (mean difference, 1.83 mm; 95% CI = 1.36 to 2.29). No differences were found for the LGM. Heterogeneity across the studies was high, and all the three included studies were performed in one country. Conclusions: Adding PCs to OFD for the treatment of mandibular Class II furcation defects may lead to slight improvements in clinical parameters. Nonetheless, because of the high heterogeneity of the very small number of reported studies and the small effect size, no definitive conclusion can be achieved about the clinical application of such a treatment option.     

Evaluation of Recession Defects Treated With Coronally Advanced Flaps and Either Recombinant Human Platelet‐Derived Growth Factor‐BB Plus β‐Tricalcium Phosphate or Connective Tissue: Comparison of Clinical Parameters at 5 Years

Background: In a previously reported split‐mouth, randomized controlled trial, Miller Class II gingival recession defects were treated with either a connective tissue graft (CTG) (control) or recombinant human platelet‐derived growth factor‐BB + β‐tricalcium phosphate (test), both in combination with a coronally advanced flap (CAF). At 6 months, multiple outcome measures were examined. The purpose of the current study is to examine the major efficacy parameters at 5 years. Methods: Twenty of the original 30 patients were available for follow‐up 5 years after the original surgery. Outcomes examined were recession depth, probing depth, clinical attachment level (CAL), height of keratinized tissue (wKT), and percentage of root coverage. Within‐ and across‐treatment group results at 6 months and 5 years were compared with original baseline values. Results: At 5 years, all quantitative parameters for both treatment protocols showed statistically significant improvements over baseline. The primary outcome parameter, change in recession depth at 5 years, demonstrated statistically significant improvements in recession over baseline, although intergroup comparisons favored the control group at both 6 months and 5 years. At 5 years, intergroup comparisons also favored the test group for percentage root coverage and change in wKT, whereas no statistically significant intergroup differences were seen for 100% root coverage and changes to CAL. Conclusions: In the present 5‐year investigation, treatment with either test or control treatments for Miller Class II recession defects appear to lead to stable, clinically effective results, although CTG + CAF resulted in greater reductions in recession, greater percentage of root coverage, and increased wKT.     

Biofunctionalization of titanium implants with a biomimetic active peptide (P‐15) promotes early osseointegration

Objectives: The early stages of peri‐implant bone formation play an essential role in the osseointegration and long‐term success of dental implants. By incorporating bioactive coatings, this biofunctionalization of implant surfaces may enhance the attachment of the implant to the surrounding bone and stimulate bone regeneration. Material and methods: To demonstrate faster osseointegration, the surfaces of dental implants were grit‐blasted and acid‐etched. They were then coated with hydroxyapatite (HA) and experimental implants were further coated with a biomimetic active peptide (P‐15) in one of two concentrations. These biofunctionalized samples and controls with no peptide were placed in the forehead region of 12 adult pigs. Six animals were evaluated for a period of 14 or 30 days. Results: Histomorphometric analysis demonstrated that the implants with the high concentration of P‐15 had significantly higher percentage of bone‐to‐implant contact (BIC) at 14 (P=0.018) and 30 (P=0.015) days compared with the other groups. Both concentrations of P‐15 showed increased peri‐implant bone density compared to the control group at 30 days. Conclusion: Biofunctionalization of the implant surface with a biomimetic active peptide leads to significantly increased BIC rates at 14 and 30 days and higher peri‐implant bone density at 30 days. To cite this article:
Lutz R, Srour S, Nonhoff J, Weisel T, Damien CJ, Schlegel KA. Biofunctionalization of titanium implants with a biomimetic active peptide (P‐15) promotes early osseointegration.
Clin. Oral Impl. Res. 21 , 2010; 726–734.
doi: 10.1111/j.1600‐0501.2009.01904.x     

Platelet‐Poor and Platelet‐Rich Plasma Stimulate Bone Lineage Differentiation in Periodontal Ligament Stem Cells

Background: Plasma‐derived fractions have been used as an autologous source of growth factors; however, limited knowledge concerning their biologic effects has hampered their clinical application. In this study, the authors analyze the content and specific effect of both platelet‐rich plasma (PRP) and platelet‐poor plasma (PPP) on osteoblastic differentiation using primary cultures of human periodontal ligament stem cells (HPLSCs). Methods: The authors evaluated the growth factor content of PRP and PPP using a proteome profiler array and enzyme‐linked immunosorbent assay. HPLSCs were characterized by flow cytometry and differentiation assays. The effect of PRP and PPP on HPLSC bone differentiation was analyzed by quantifying calcium deposition after 14 and 21 days of treatment. Results: Albeit at different concentrations, the two fractions had similar profiles of growth factors, the most representative being platelet‐derived growth factor (PDGF) isoforms (PDGF‐AA, ‐BB, and ‐AB), insulin‐like growth factor binding protein (IGFBP)‐2, and IGFBP‐6. Both formulations exerted a comparable stimulus on osteoblastic differentiation even at low doses (2.5%), increasing calcium deposits in HPLSCs. Conclusions: PRP and PPP showed a similar protein profile and exerted comparable effects on bone differentiation. Further studies are needed to characterize and compare the effects of PPP and PRP on bone healing in vivo.     

Autologous Platelet‐Rich Fibrin in the Treatment of 3‐Wall Intrabony Defects in Aggressive Periodontitis: A Randomized Controlled Clinical Trial

Background: Platelet‐rich fibrin (PRF) has recently been applied in osseous regeneration. The aim of the present study is to explore the efficacy of PRF in treatment of intrabony defects (IBDs) in aggressive periodontitis. Methods: Fifty‐four IBDs in 17 patients were treated either with autologous PRF with open flap debridement (OFD) or OFD alone. Clinical and radiologic parameters such as probing depth (PD), clinical attachment level (CAL), IBD depth, and percentage defect change were recorded at baseline and 9 months postoperatively. Results: Mean PD reduction and mean CAL gain were significantly greater in PRF compared with the control group. Furthermore, a significantly greater percentage of mean bone defect change was found in the PRF group. Conclusion: Within the limits of the present study, there is greater bone fill at sites treated with PRF with conventional OFD than conventional OFD alone.