Role of Platelet Rich Fibrin and Platelet Rich Plasma in Wound Healing of Extracted Third Molar Sockets: A Comparative Study

Aims and objectives

This prospective study was done to evaluate and compare the utility and effectiveness of platelet rich fibrin (PRF) with that of platelet rich plasma (PRP) on soft tissue healing and bone tissue healing of extracted third molar sockets.

Materials and methods

This study included split mouths of 20 patients who underwent bilateral extraction of impacted third molars. During the same appointment, following which PRF and PRP were prepared from patients’ autologous blood and placed in right and left extracted sockets, respectively. The data for soft tissue healing were recorded at end of 1 week, using healing index of Landry et al. and the data for bone tissue healing were recorded at the end of 4 months using digitalized orthopantomogram images on Adobe Photoshop CS; which was then compared between the two sites of the same patient.

Results

The mean values of soft tissue healing collected at 1 week post-operative, for PRF group were significantly higher as compared to PRP group. And the mean values of bone density collected at the end of fourth month post-operative, for PRF group were also significantly higher as compared to PRP group. Both tests showed p value of 0.00.

Conclusion

PRF is significantly better in promoting soft tissue healing and also faster regeneration of bone after third molar extraction, in comparison with PRP. This could be attributed to simpler preparation protocols of PRF over PRP and the ability of PRF to release growth factors in a controlled way.     

Comparative release of growth factors from PRP,PRF, and advanced-PRF

Objectives

The use of platelet concentrates has gained increasing awareness in recent years for regenerative procedures in modern dentistry. The aim of the present study was to compare growth factor release over time from platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and a modernized protocol for PRF, advanced-PRF (A-PRF).

Materials and methods

Eighteen blood samples were collected from six donors (3 samples each for PRP, PRF, and A-PRF). Following preparation, samples were incubated in a plate shaker and assessed for growth factor release at 15 min, 60 min, 8 h, 1 day, 3 days, and 10 days. Thereafter, growth factor release of PDGF-AA, PDGF-AB, PDGF-BB, TGFB1, VEGF, EGF, and IGF was quantified using ELISA.

Results

The highest reported growth factor released from platelet concentrates was PDGF-AA followed by PDGF-BB, TGFB1, VEGF, and PDGF-AB. In general, following 15–60 min incubation, PRP released significantly higher growth factors when compared to PRF and A-PRF. At later time points up to 10 days, it was routinely found that A-PRF released the highest total growth factors. Furthermore, A-PRF released significantly higher total protein accumulated over a 10-day period when compared to PRP or PRF.

Conclusion

The results from the present study indicate that the various platelet concentrates have quite different release kinetics. The advantage of PRP is the release of significantly higher proteins at earlier time points whereas PRF displayed a continual and steady release of growth factors over a 10-day period. Furthermore, in general, it was observed that the new formulation of PRF (A-PRF) released significantly higher total quantities of growth factors when compared to traditional PRF.

Clinical relevance

Based on these findings, PRP can be recommended for fast delivery of growth factors whereas A-PRF is better-suited for long-term release.

     

Mandibular Third Molar Extraction Wound Healing With and Without Platelet Rich Plasma: A Comparative Prospective Study

Aims

To evaluate the efficacy of autologous platelet rich plasma (PRP) in regeneration of bone and to assess clinical compatibility of the material in mandibular third molar extraction socket.

Objective of the Study

To compare the healing of mandibular third molar extraction wounds with and without PRP.

Materials and Methods

Group A consists of the 30 patients where PRP will be placed in the extraction socket before closure of the socket. Group B consists of 30 patients who will be the control group where the extraction sockets will be closed without any intra socket medicaments. The patients would be allocated to the groups randomly.

Results

Soft tissue healing was better in study site compared to control site. The result of the study shows rapid bone regeneration in the extraction socket treated with PRP when compared with the socket without PRP. Evaluation for bone blending and trabecular bone formation started earlier in PRP site compared to control, non PRP site. Also there was less postoperative discomfort on the PRP treated side.

Conclusion

Autologous PRP is biocompatible and has significant improved soft tissue healing, bone regeneration and increase in bone density in extraction sockets.     

Comparison of platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factor (CGF) in rabbit-skull defect healing

Objectives

The objective of this study was to evaluate the effect of platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factor (CGF) on bone healing.

Study design

Twelve rabbits were included in this randomized, blinded, prospective study. 15-mm × 10-mm-sized defects were created in the parietal bone, filled with PRP, PRF, CGF, and void. The bone mineral density and bone volume were analyzed with microscopic computed tomography (micro-CT) and histomorphometrics at the 6th and 12th week.

Results

In micro-CT analysis, bone mineral density and bone volume were greater in the experimental group than in controls at both 6th and 12th week, but not among the experimental groups. Similarly, histomorphometric examination revealed that more bone formation was seen in the experimental group.

Conclusion

The addition of PRP, PRF, and CGF had significantly increased bone formation at the 6th week. The effect of PRP, PRF, and CGF was similar and may be useful in the future to increase the success rate of bone grafting.     

Clinical Evaluation of Use of Platelet Rich Plasma in Bone Healing

Background

Tooth extraction is performed for a wide variety of reasons as we know. Several techniques aiming at enhancing the regeneration process in the extraction socket have been adopted such as filling the socket with autogenous bone grafts or bone substitutes. We know platelets play a central role in hemostasis and healing processes but relative contradictory effect of platelet in bone regenerating capacity have been published in different in vitro and in vivo studies.

Method

To explore this we used platelet-rich plasma (PRP) (autogenous) alone in empty extraction socket of bilateral impacted mandibular third molars. For that we selected five patients having bilateral impacted teeth. Out of two sockets one was used as intervention by filling with PRP and the other was allowed to heal without PRP. All patients were followed for clinical and radiological evaluation by using digital OPG view after 1 week, 1, 2 and 4 months period.

Result and conclusion

PRP enhanced the osteogenic response in initial bone healing at 1 month duration but there was no added benefit in late bone healing at 4 months period compared in both intervention and control groups. However PRP significantly improved the soft tissue healing in PRP treated sites compared to control group.     

Platelet Rich Fibrin: A Novel Approach for Osseous Regeneration

 

To evaluate the efficacy of autologous platelet rich fibrin in soft tissue healing and bone regeneration in mandibular third molar extraction sockets.

Method

The study was conducted in 20 patients visiting in outpatient department of Oral and Maxillofacial Surgery, requiring extraction of bilateral mandibular third molar, following extraction platelet rich fibrin (PRF) was placed in one extraction sockets, the other socket was studied as the control sites with no PRF. The patient were assessed for post operative pain, soft tissue healing and trabecular pattern in healing bone. Radiological assessment of the extraction site was done for period of 3 months to evaluate the change in bone density.

Results

Pain was less in study side compare to control site soft tissue was healing was better in study site. Evaluation of trabecular bone formation started earlier in PRF site compare to control site. The evaluation of bone density by radiological assessment showed the grey level value calculated after 3 months at the PRF site well comparatively higher than the average baseline value of the bone density at the extraction site in control site.

Conclusion

The study showed that autologous PRF is biocompatible and has significantly improved soft tissue healing. Bone regeneration and increase in bone density in extraction sockets. However, a more elaborate study with a large number of clinical cases is essential to be more conclusive regarding its efficacy.     

Autologous Platelet Rich Plasma After Third Molar Surgery: A Comparative Study

Purpose

This study is an attempt to evaluate the use of autologous platelet rich plasma (PRP) to promote wound healing and osseous regeneration in human third molar extraction sockets.

Materials and method

PRP was prepared after two centrifugation and the gelling agent used was freshly prepared 10% calcium chloride.PRP gel was placed in one of the extracted sockets of bilateral impacted mandibular third molars. IOPA Xrays were used to evaluate the wound dehiscence, probing depth, bone density & alveolar bone level after 1st, 2nd and 7th day and 3rd & 6th month respectively.

Results

On evaluation, it was found that PRP grafted sockets showed dehiscence in 8% cases. The decrease in alveolar bone level was highly significant in PRP grafted sockets in 3rd and 6th month post operatively. There was significant difference between pre-operative density of adjacent bone and bone formed in extraction sockets at 3rd and 6th month in PRP grafted sockets. There was significant reduction in probing depth from initial period to 3 and 6 months in both the groups, but PRP grafted sockets showed greater decrease in probing depth.

Conclusion

PRP is an inexpensive and widely available modality to minimize postoperative complication and enhance both hard and soft tissue healing potentials. This autologous product eliminates concern about immunogenic reaction and disease transmission. Its beneficial outcomes in dental clinic, including decrease in bleeding and rapid wound healing hold promise for further procedures.PRP is thus a new application in tissue engineering and developing area for clinician and researchers.     

A Prospective Study Involving the Use of Platelet Rich Plasma in Enhancing the Uptake of Bone Grafts in the Oral and Maxillofacial Region

Abstract

Platelet-rich plasma (PRP) is an autologous product that contains highly concentrated number of platelets in a small volume of plasma, derived from whole blood by gradient density centrifugation. It has been speculated that local growth factors in human platelets (insulin-like growth factor, IGF; transforming growth factor, TGF-β; platelet derived growth factor, PDGF) would enhance healing of grafts and also counteract resorption. The aim of this study was to evaluate efficacy of PRP on early healing after autogenous bone grafting. Of the twenty patients selected ten were treated with autogenous bone graft and PRP (PRP group) and other ten with autogenous bone graft alone (non-PRP group). PRP group consisted of two benign tumor of mandible, one post surgical defect, two unilateral alveolar cleft, one bilateral alveolar cleft with skeletal class III malocclusion, one maxillary hypoplasia, one oronasal fistula, one recurrent tumor of mandible, one multiple impacted mandibular teeth. Non-PRP group consisted of seven benign tumor of jaw, one keratocyst odontogenic tumor, one orbital blow out fracture, one residual traumatic defect. Biopsies were taken in the native bone, PRP treated grafted bone, grafted bone without PRP at 3 months to assess the maturity of bone. Radiographic imaging was performed by panoramic radiography at 3 and 6 months to evaluate bone opacity of grafted bone on comparison with native bone and computerized tomography at 6 months to evaluate grafted bone morphologically and to measure bone density in Hounsfield units. Microscopic results showed that significantly more matured bone was formed at PRP treated sites as that of native bone and immature bone in controls after 3 months of healing. Bone opacity of PRP treated bone grafts was close to that of native bone than that of non-PRP treated bone grafts on panoramic radiograph at 3 and 6 months. There was graft loss in three cases and graft resorption in one case of non-PRP treated bone grafts at 6 months. In PRP group the compact bone was clearly differentiated from cancellous bone as in native bone and thick in five cases, thin in five cases. In non-PRP group the compact bone was thin as a whole. Comparing native bone group and PRP group the CT value of PRP treated bone graft was more or less close to native bone group and comparing native bone group and non-PRP group CT value was low in non-PRP treated bone graft. Whereas when comparing PRP and non-PRP group CT value was higher in PRP group. Autologous PRP was a safe, biocompatible, effective, source for growth factors and carries no risk of transmissible diseases. It enhances and accelerates bone regeneration of autogenous bone grafts.     

Platelet-rich plasma plus bioactive glass in the treatment of intra-bony defects: a study in dogs

Objective

This study was designed to evaluate, histomorphometrically, the association of platelet-rich plasma (PRP) and bioactive glass (BG) in the treatment of periodontal intrabony defects.

Material and Methods

Nine mongrel dogs were included in the study. Three-wall intrabony defects were surgically created at the mesial and distal aspect of first mandibular molar and exposed to plaque accumulation for 1 month. The defects were randomly assigned to the groups: control, BG, PRP, PRP+BG. Dogs were sacrificed 90 days after the surgeries. The histometric parameters evaluated were: length of sulcular and junctional epithelium, connective tissue adaptation, new cementum, new bone, defect extension and area of new bone filling the defect.

Results

A superior area of new bone was observed in PRP+BG and BG (13.80±2.32 mm² and 15.63±2.64 mm², respectively) when compared to the other groups (8.19±1.46 mm² and 8.81±1.47 mm² for control and PRP, respectively). No statistically significant differences were observed in the remaining parameters.

Conclusion

Within the limits of this study, it may be concluded that PRP failed to provide statistically significant improvements in the histometric parameters.     

Platelet-rich plasma in the treatment of Class II furcation defects: a histometrical study in dogs

Objective

This study was designed to evaluate the potential adjunctive benefits of platelet-rich plasma (PRP) when used with guided-tissue regeneration (GTR) and bioactive glass (BG) in the treatment of Class II furcation lesions.

Material and Methods

Bilateral Class II furcation lesions were surgically created and allowed to become chronic in the mandibular third premolars of 9 dogs. The defects were randomly assigned to: A) GTR+BG and B) GTR+BG+PRP. Similar defects were created in the maxillary third premolars and received the same treatments after 45 days. Dogs were sacrificed 90 days after the first treatment. The histometric parameters evaluated were: connective tissue adaptation, new cementum, new bone, mineralized bone area, non-mineralized bone area, and residual BG particle area.

Results

Data analysis showed a superior length of new cementum and a greater mineralized bone area for group B in both periods (p<0.05). The non-mineralized bone area was greater in the control group (p<0.05) in both periods.

Conclusion

Within the limits of this study, it can be concluded that the use of PRP in the treatment of Class II furcation defects may enhance the amount of new cementum and provide a more mineralized bone in a shorter period of time.     

Effects of Platelet-rich Plasma and Cell Coculture on Angiogenesis in Human Dental Pulp Stem Cells and Endothelial Progenitor Cells

Introduction

Platelet-rich plasma (PRP) has been described as platelet concentrate. Growth factors released by activated platelets can improve wound vasculogenesis and enhance wound healing. In this study, we used PRP instead of serum to culture human dental pulp stem cells (hDPSCs) and endothelial progenitor cells (EPCs) and investigated revascularization ability. The effect of hDPSC and EPC coculture on vasculogenesis was also studied.

Methods

PRP was prepared by secondary centrifugation. Real-time polymerase chain reaction and Western blotting were used to determine the expression of vasculogenesis-related factors vascular endothelial growth factor, platelet-derived growth factor, fetal liver kinase 1 (Flk-1), and stromal cell-derived factor 1 (SDF-1) in cultured hDPSCs and EPCs. The cells were divided into 4 groups: EPCs + 10% fetal bovine serum (FBS), EPCs + 10% PRP, EPCs + hDPSCs + 10% FBS, and EPCs + hDPSCs + 10% PRP. Then, the formation of vessel-like structures was tested by the tube formation assay.

Results

On day 3, the expression levels of all the markers in the coculture groups were much higher than in the single-culture groups and were also higher in the PRP groups compared with the FBS groups (P < .05), except for SDF-1. Expression levels were significantly higher in the experimental groups (EPCs + 10% PRP, EPCs + hDPSCs + 10% FBS, and EPCs + hDPSCs + 10% PRP) than in the control group (EPCs + 10% FBS) and in the PRP groups/coculture groups compared with the FBS groups/single-culture groups (P < .01). The tube formation assay showed the area of vessel-like structures formed by the PRP group to be larger than in the FBS group (P < .05).

Conclusions

PRP and coculture can both promote vasculogenesis, and PRP can promote EPCs to form vessel-like structures.     

Analysis of a rapid, simple, and inexpensive technique used to obtain platelet-rich plasma for use in clinical practice

The use of platelet-rich plasma (PRP) has become more generally accepted, and implant dentists are using PRP more frequently to promote the healing of oral surgical and/or periodontal wounds. Critical elements of PRP are thought to be growth factors contained within the concentrated platelets. These growth factors are known to promote soft-tissue healing, angiogenesis and osteogenesis. We present a rapid, simple, and inexpensive methodology for preparing PRP using the Cliniseal centrifuge method. This study demonstrates that platelets are concentrated approximately 6-fold without altering platelet morphology. Further we demonstrate that key growth factors, platelet-derived growth factor BB (PDGF-BB), transforming growth factor B (TGF-B1), vasculature endothelial growth factor (VEGF), and epidermal growth factor (EGF) are present in comparable or higher concentrations than those reported with the use of other techniques. Prolonged bench set time (>3 hours) after centrifugation resulted in decreased concentration of TGF-B1 but not decreased concentration of PDGF-BB, VEGF, or EGF. This study confirms the molecular aspects of PRP obtained using this inexpensive and efficient methodology.     

Comparison of Point-of-Care Methods for Preparation of Platelet Concentrate (Platelet-Rich Plasma)

Purpose: This study analyzed the concentrations of platelets and growth factors in platelet-rich plasma (PRP), which are likely to depend on the method used for its production. Materials and Methods: The cellular composition and growth factor content of platelet concentrates (platelet-rich plasma) produced by six different procedures were quantitatively analyzed and compared. Platelet and leukocyte counts were determined on an automatic cell counter, and analysis of growth factors was performed using enzyme-linked immunosorbent assay. Results: The principal differences between the analyzed PRP production methods (blood bank method of intermittent flow centrifuge system/platelet apheresis and by the five point-of-care methods) and the resulting platelet concentrates were evaluated with regard to resulting platelet, leukocyte, and growth factor levels. The platelet counts in both whole blood and PRP were generally higher in women than in men; no differences were observed with regard to age. Statistical analysis of platelet-derived growth factor AB (PDGF-AB) and transforming growth factor Β1 (TGF-Β1) showed no differences with regard to age or gender. Platelet counts and TGF-Β1 concentration correlated closely, as did platelet counts and PDGF-AB levels. There were only rare correlations between leukocyte counts and PDGF-AB levels, but comparison of leukocyte counts and PDGF-AB levels demonstrated certain parallel tendencies. Conclusions: TGF-Β1 levels derive in substantial part from platelets and emphasize the role of leukocytes, in addition to that of platelets, as a source of growth factors in PRP. All methods of producing PRP showed high variability in platelet counts and growth factor levels. The highest growth factor levels were found in the PRP prepared using the Platelet Concentrate Collection System manufactured by Biomet 3i.     

Comparative Study of Alveolar Bone Height and Implant Survival Rate Between Autogenous Bone Mixed with Platelet Rich Plasma Versus Venous Blood for Maxillary Sinus Lift Augmentation Procedure

Aim and Objectives

The aim of this study was to evaluate changes in alveolar bone height by means of radiographic examination and Straumann implant survival rate following maxillary sinus lift augmentation using autogenous bone in combination with platelet rich plasma (PRP) versus venous blood (VB).

Methods

Fifty patients requiring sinus lift augmentation procedure included in the study were divided into two groups (n = 25). During the procedure the sub antral sinus cavity was augmented using autogenous bone taken from mandibular ramus area and mixed with PRP in one group and autogenous bone mixed with VB in the other group. Orthopantomograms were taken preoperatively, immediate, at 6 months and 1 year postoperatively. Height of alveolar bone at the site of sinus augmentation was measured on the radiographs. One hundred and twenty-one Straumann dental implants were placed after healing period.

Results

Age of the patients in the study groups ranged from 36 to 69 years. Differences in mean values of bone height measurements recorded in the PRP series revealed significant differences among the three subgroups (P = 0.001). Significant differences were noted between immediate postop and 6 month (P < 0.01), immediate postop and year (P < 0.01). In the VB series also significant differences were revealed among the three subgroups (P = 0.0280). Significant differences were noted between immediate postop and 6 month (P < 0.05). Comparison of results of subgroups of the two series at the three intervals revealed significant differences at ‘immediate postop’ values (P = 0.0002) and ‘sixmon’ values (P = 0.0435). Differences between ‘year’ values were not significant. Two implants were lost in PRP group.

Conclusion

The results of this limited study reveals that both groups recorded a good increase in the alveolar bone height after sinus augmentation and showed no significant differences between these groups when compared to each other at 1 year postoperatively. When both sub groups compared with immediate postop to year, PRP group showed significant difference and blood group showed no significant difference.     

Optimization of growth inducing factors for colony forming and attachment of bone marrow-derived mesenchymal stem cells regarding bioengineering application

PURPOSE

These days, mesenchymal stem cells (MSCs) have received worldwide attention because of their potentiality in tissue engineering for implant dentistry. The purpose of this study was to evaluate various growth inducing factors in media for improvement of acquisition of bone marrow mesenchymal stem cells (BMMSCs) and colony forming unit-fibroblast (CFU-F).

MATERIALS AND METHODS

The mouse BMMSCs were freshly obtained from female C3H mouse femur and tibia. The cells seeded at the density of 10⁶/dish in media supplemented with different density of fetal bovine serum (FBS), 1α, 25-dihydroxyvitamin (VD3) and recombinant human epidermal growth factor (rhEGF). After 14 days, CFU-F assay was conducted to analyze the cell attachment and proliferation, and moreover for VD3, the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay was additionally conducted.

RESULTS

The cell proliferation was increased with the increase of FBS concentration (P<.05). The cell proliferation was highest at the density of 20 ng/mL rhEGF compared with 0 ng/mL and 200 ng/mL rhEGF (P<.05). For VD3, although the colony number was increased with the increase of its concentration, the difference was not statistically significant (P>.05).

CONCLUSION

FBS played the main role in cell attachment and growth, and the growth factor like rhEGF played the additional effect. However, VD3 did not have much efficacy compare with the other two factors. Improvement of the conditions could be adopted to acquire more functional MSCs to apply into bony defect around implants easily.     

Poor oral Hygiene may be the Sole Cause of Oral Cancer

Purpose

The purpose of this case–control study was to draw attention to the possibility that poor oral hygiene resulting from infrequent and inadequate use of chewing sticks might be the sole cause of oral cancer in 60 patients investigated in the maxillofacial units of two specialist hospitals in eastern Nigeria.

Methods

Sixty cases and 60 controls made up the study population. We matched them for age, gender, period of admission and study site. The interview of all the participants contained data on demographic factors, family history of cancer, tobacco habits, oral hygiene, dietary habits and use of alcohol. We took biopsies of the lesions for histo-pathological examination. We entered the collected data into Microsoft excel package and transported it to Stata for generation of statistical test.

Result

Poor oral hygiene due to infrequent tooth brushing was associated with primary oral cancer in this patient sample. On the other hand, frequent tooth brushing was related to healthy status.

Conclusion

In the absence of other known carcinogens, poor oral hygiene may be the single factor that caused oral cancer in these subjects. Research is needed to investigate the pathological mechanism that is associated with this risk factor.

Electronic supplementary material

The online version of this article (doi:10.1007/s12663-012-0359-5) contains supplementary material, which is available to authorized users.     

Risk assessment for clinical attachment loss of periodontal tissue in Korean adults

PURPOSE

The purpose of this study was to assess the prevalence and extent of clinical attachment loss of periodontal tissue and to find out variables related to clinical attachment loss (CAL) in Korean adults older than 40 years of age.

MATERIALS AND METHODS

Data were collected from 2,519 subjects who were part of a cohort study conducted in Ansan city by Korea University Medical School for Korean Genome project. Age, sex, smoking, drinking, fast glucose, blood pressure, obesity and total cholesterol levels were examined. The oral examination included probing pocket depth, gingival recession and CAL of Ramford''s teeth. The severity of periodontitis was classified based on the mean value of CAL. The relationship between each risk factor and the severity of CAL was independently estimated using the chi-square test, the test or one-way ANOVA. Multiple regression analysis was used to determine the significance of each factor in the periodontal disease.

RESULTS

The prevalences of clinical attachment between 1 and 3 mm, between 3 and < 5 mm, and ≥ 5 mm were 80.27%, 16.75% and < 1%, respectively. Although the univariate analysis showed age, gender, smoking, fasting glucose, blood pressure and total cholesterol levels were significantly related to the severity of CAL, multiple regression analysis indicated that age (P < .0001), gender (P < .0001) and smoking (P < .05) were only significantly related.

CONCLUSION

Older age, male gender and smoking were significant risk factor for the increase of CAL, and these may be useful indicators of periodontitis high-risk groups.     

Saliva and dental erosion

Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear.

Objective

This review discusses the role of salivary factors on the development of dental erosion.

Material and Methods

A search was undertaken on MEDLINE website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party.

Results

Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion.

Conclusions

Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.     

A Comparative Evaluation of Concentrated Growth Factor and Platelet-rich Fibrin on the Proliferation,Migration, and Differentiation of Human Stem Cells of the Apical Papilla

Introduction

Concentrated growth factor (CGF) is considered to be a natural biomaterial that is better than platelet-rich fibrin (PRF) in bone regeneration, but there is little information acquired in regenerative endodontics. Therefore, the purpose of this study was to evaluate their effects on the proliferation, migration, and differentiation of human stem cells of the apical papilla (SCAPs).