In Vitro Evaluation of Osteoblast Response to the Effect of Injectable Platelet-rich Fibrin Coating on Titanium Disks.

AIM: Biomimetic implant surface coatings can improve osteoblast response and enhance osseointegration. This study aimed to assess the response of osteoblast-like cell line (MG-63) coating of injectable platelet-rich fibrin on titanium discs. MATERIALS AND METHODS: Injectable-PRF (i-PRF) was prepared by centrifugation of blood at 700 rpm for 3 minutes without any anti-coagulant in i-PRF tubes. Ten commercially pure titanium discs were divided into control groups comprising plain discs, and test group, titanium discs were coated with i-PRF. These were then added to the cultured MG-63 cells. Cell proliferation, alkaline phosphatase production, and mineralization were assessed in both groups at day 1, 7, 14, and 21. RESULTS: The cell proliferation, alkaline phosphatase production, and mineralization increased significantly from day 1 to day 21 in both test and control groups and was significantly higher in the test group than in control group at day 1, 7, 14, and 21 (p <0.001). CONCLUSIONS: Coating of titanium discs with i-PRF causes increased proliferation, alkaline phosphatase production, and increased mineralization at day 1, 7, 14, and 21 in MG-63 osteoblast-like cells. CLINICAL SIGNIFICANCE: Improved osteoblast proliferation and mineralization demonstrate enhanced activity on the surface of an implant, which in turn may lead to increased bone to implant contact and faster/ and/or enhanced osseointegration.

Immediate Ridge Augmentation Using Autogenous Tooth Root as a Block Graft in a Periodontally Hopeless Extraction Site: A Pilot Study.

The aim of the our study was to assess the efficacy of autogenous tooth root as a block bone graft in reconstructing the vertical and horizontal dimensions at periodontally hopeless extraction sites both clinically and radiographically. A total of 13 patients having a tooth with periodontally hopeless prognosis and indicated for extraction were included in the study. Following atraumatic extraction, the tooth was processed to create a decoronated cementum-free dentin block which was used to augment the extraction socket. The augmentation of periodontally hopeless socket with tooth block autograft resulted in a gain of clinical ridge width of 5.9 mm radiographically, the apico-coronal defect depth reduced up to 8.2 mm (P = .001), and a gain in ridge width of 5.8 mm postoperatively after 6 months (P = .001). The present study demonstrated the effectiveness of using tooth root as a block graft for ridge augmentation in the periodontally hopeless extraction site making it suitable for implant placement in future.

Utilization of Census Tract-Based Neighborhood Poverty Rates to Predict Non-adherence to Screening Colonoscopy.

OBJECTIVES: Efforts to improve colorectal cancer (CRC) screening rates include recognizing predictors of colonoscopy non-adherence and identifying these high-risk patient populations. Past studies have focused on individual-level factors but few have evaluated the influence of neighborhood-level predictors. We sought to assess the effect of census tract-based neighborhood poverty rates on scheduled screening colonoscopy non-adherence. METHODS: In this prospective observational cohort study, data from electronic medical records and appointment tracking software were collected in 599 patients scheduled to undergo outpatient CRC screening colonoscopy at two academic endoscopy centers between January 2011 and December 2012. Non-adherence was defined as failure to attend a colonoscopy appointment within 1 year of the date it was electronically scheduled. Neighborhood poverty rate was determined by matching patients' self-reported home address with their corresponding US census tract. Individual factors including medical comorbidities and prior appointment adherence behavior were also collected. RESULTS: Overall, 17% (65/383) of patients were non-adherent to scheduled colonoscopy at 1-year follow-up. Neighborhood poverty rate was a significant predictor of non-adherence to scheduled screening colonoscopy in multivariate modeling (OR 1.53 per 10% increase in neighborhood poverty rate, 95% CI 1.21-1.95, p < 0.001). By incorporating the neighborhood poverty rate, screening colonoscopy non-adherence was 31% at the highest quartile compared to 14% at the lowest quartile of neighborhood poverty rates (p = 0.006). CONCLUSIONS: Census tract-based neighborhood poverty rates can be used to predict non-adherence to scheduled screening colonoscopy. Targeted efforts to increase CRC screening efficiency and completion among patients living in high-poverty geographic regions could reduce screening disparities and improve utilization of endoscopy unit resources.

Maxillary Sinus Augmentation Using Hydraulic Pressure by Lateral Approach and Simultaneous Implant Placement: Clinicoradiographic Study.

The purpose of this study was to assess clinically and radiographically efficacy of maxillary sinus augmentation using hydraulic pressure in a lateral approach with immediate implant placement. In a total of 10 patients having less than 4 to 6 mm of subantral bone height, lateral approach sinus membrane elevation procedure was performed using hydraulic pressure with the help of a specialized water lift kit followed by grafting and simultaneous implant placement. Cone beam computed tomography analysis was used to assess the change in subantral bone height from baseline to the 6 months postoperatively. Radiographically, subantral bone height increased from 3.86 ± 1.423 mm at baseline to 15.49 ± 2.73 mm at 6 months postoperatively with a gain of 11.63 + 2.63 mm (P < 0.001). Thus, it is concluded that hydraulic pressure may be efficiently used in lateral sinus augmentation procedures along with simultaneous implant placement.

Biological activation of bone grafts using injectable platelet-rich fibrin.

Platelet-rich fibrin (PRF) is gaining acceptance as a bioactive surgical additive in regenerative dentistry. However, PRF has only been available in gel or membrane form and is not suitable for injection. Recently, however, a liquid, injectable PRF has been introduced. This paper introduces the concept of injectable PRF and discusses its applications for biologic activation of bone grafts.

An Update on the Protocols and Biologic Actions of Platelet Rich Fibrin in Dentistry.

Platelet rich fibrin (PRF) is a surgical biologic additive that is prepared by manipulation of autologous blood. It has now evolved to become one of the most widely used platelet concentrate in dentistry. It has almost replaced Platelet rich plasma (PRP) for usage owing to its advantages such as being 100% autogenous, easy technique, time and cost effectiveness, superior & prolonged growth factor release. It finds varied applications in dentistry including management of gingival recession, for guided bone regeneration in periodontal, peri-implant and endodontic bone defects. Since its inception in 2001 by Choukroun & co-workers, there has been in-depth research regarding its clinical applications, biologic actions, various technique modifications and optimizations. Several modifications of the conventional protocol like the advanced PRF, injectable PRF, PRF lysate and Titanium-prepared PRF. Hence, the aim of this article to review the biological properties of platelet rich fibrin and the advancement in the PRF technology since its inception.

Assessment of Intraobserver and Interobserver Agreement of a New Classification System for Retrograde Periimplantitis.

BACKGROUND: Retrograde periimplantitis (RPI) is the inflammatory disease that affects the apical part of an osseointegrated implant while the coronal portion of the implant sustains a normal bone-to-implant interface. The aim of the current study was to assess the intraexaminer and interexaminer reliability of a proposed new classification system for RPI. MATERIALS AND METHODS: After thorough electronic literature search, 56 intraoral periapical radiographs (IOPA) of implants with RPI were collected and were classified by 2 independent reviewers as per the new classification system into one of the 3-mild, moderate, and advanced-classes based on the amount of bone loss from the apex of the implant to the most coronal part as a percentage of the total implant length. The IOPAs were assessed twice by the same examiners and both were blinded to each other's observations. RESULTS: The intraobserver agreement ranged from 0.85 to 0.91, which falls under the category of almost perfect agreement. The interexaminer agreement was found to be 0.83, also considered as almost perfect agreement. CONCLUSION: The proposed classification shows good intraexaminer and interexaminer reliability and can be used for treatment planning and prognosis in cases of RPI.

A Radiographic Classification for Retrograde Peri-implantitis.

BACKGROUND: Retrograde peri-implantitis (RPI) is an inflammatory disease that affects the apical part of an osseointegrated implant, while the coronal portion of the implant sustains a normal bone-to-implant interface. It is a diagnostic and therapeutic dilemma for implantologists. There is lack of a standard classification system and a definite treatment algorithm for the same. This article aims to introduce a classification system for RPI based on the radiographic amount of bone loss around an implant apex. MATERIALS AND METHODS: A search of PubMed database was conducted with the keywords "retrograde peri-implantitis" and "implant periapical lesion." Preoperative intraoral periapical (IOPA) radiographs of implants with RPI in case reports/case series were compiled. A total of 54 lOPAs from 36 articles were compiled and were assessed. RESULTS: Three different classes were proposed. The amount of bone loss from the apex of the implant to the most coronal part of radiolucency was calculated as a percentage of the total implant length and classified into one of the three classes: Mild, moderate, and advanced. Treatment options and prognosis have been suggested for each class. CONCLUSION: The proposed classification may allow for an easy and reproducible radiographic assessment of the RPI lesion and may serve as a guideline to prognosis and treatment planning.

Titanium Corrosion: Implications For Dental Implants.

Titanium has been considered as one of the most biocompatible metals. Studies testing its corrosion resistance have proposed that the titanium oxide layer formed on the metal surface is lost under certain unavoidable conditions to which it is exposed in the oral environment. This questions its property of corrosion resistance in the oral cavity. Hence, there is a need to understand the mechanisms of corrosion, which can help in the long-term stability and function of implants. Here, we review the possible pathways of corrosion of titanium in the oral cavity, its implications and proposed methods of prevention of corrosion.

Oxidized-low density lipoprotein in gingival crevicular fluid of patients with chronic periodontitis: a possible link to atherogenesis.

OBJECTIVE: To investigate a possible link between periodontitis and atherogenesis by examining the levels of anti-oxidized low density lipoprotien (ox LDL) and low density lipoprotien (LDL) in gingival crevicular fluid (GCF) and serum of healthy subjects and chronic periodontitis patients. METHODS: Sixty male subjects (35-55 years) were grouped into 30 healthy individuals and 30 subjects with chronic periodontitis. Serum and GCF samples were obtained from each subject and were assessed for anti-ox LDL and LDL levels. RESULTS: A significant difference (p < 0.001) was found between the anti-ox-LDL levels in GCF of healthy vs chronic periodontitis groups. Also the ratio of GCF anti-ox LDL to GCF LDL was significantly higher (p < 0.001) in chronic periodontitis patients as compared to the healthy group. CONCLUSIONS: A significant rise in ox LDL level in otherwise systemically healthy chronic periodontitis patients may put these subjects at an increased risk of developing atherosclerosis.

Advanced platelet rich fibrin demonstrates improved osteogenic induction potential in human periodontal ligament cells, growth factor production and mechanical properties as compared to leukocyte and platelet fibrin and injectable platelet rich fibrin.

OBJECTIVES: This cross-sectional invitro research aimed to compare and contrast the macroscopic and microscopic, mechanical and biochemical features of leukocyte-rich platelet-rich fibrin, advanced platelet-rich fibrin, and injectable platelet-rich fibrin. MATERIALS AND METHODS: In all, 150 samples were taken from males aged 18 to 25 with good systemic health (n = 50 each for i-PRF, A-PRF, and L-PRF). The samples were assessed for clot length, clot width, membrane length and width. Microscopic parameters assessed were the distribution of cells and fibrin structure. Mechanical tests were performed for tensile strength using a universal testing machine and growth factor analysis was performed for platelet derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and transforming growth factor (TGF)- ß on Days 1, 3 and 7 using commercially available ELISA kits. The osteogenic potential was analyzed in a culture of human periodontal ligament cells for 21 days using cell viability assay, alkaline phosphatase formation and alizarin red staining for mineralization. RESULTS: L-PRF demonstrates statistically superior clot length, width, weight, membrane length, width and weight in comparison to A-PRF (p < 0.05). L-PRF demonstrates a denser fibrin structure in comparison to A-PRF and i-PRF (p < 0.05). The cells in L-PRF are most commonly situated in the proximal of the clot where as they are distributed in the proximal and middle aspect for A-PRF(p < 0.05). A-PRF demonstrates the highest tensile strength followed by L-PRF (p < 0.05). When growth factor release was evaluated, A-PRF showed noticeably increased release of all growth factors, namely PDGF-BB, TGF-ß, and VEGF, in comparison to i-PRF and L-PRF (p < 0.05). On days 7 and 14, the cell viability of human periodontal ligament cells in co-culture with A-PRF was statistically substantially greater than that of L-PRF and i-PRF (p < 0.05). Alkaline phosphatase levels were statistically substantially higher in A-PRF, followed by i-PRF and L-PRF on days 14 and 21 (p < 0.05). After 21 days of culture, A-PRF treated cultures had much more Alizarin Red staining than L-PRF and i-PRF cultures did (p < 0.05). CONCLUSION: It was determined that although L-PRF exhibits greater size and weight in comparison to A-PRF and i-PRF, A-PRF has superior mechanical properties, increased growth factor releases of TGF-b, PDGF-BB, and VEGF as well as superior cell viability, alkaline phosphatase production, and mineralization on human periodontal ligament cells. CLINICAL RELEVANCE: Based on these findings, A-PRF can be recommended for improved delivery of growth factors and osteogenesis whereas L-PRF is better-suited for applications relying on the size of membrane.

Comparison of the angiogenic efficacy of conventional leukocyte- and platelet-rich fibrin versus low-speed advanced platelet-rich fibrin: An in vitro chorioallantoic membrane assay study.

BACKGROUND: Platelet-rich fibrin (PRF) is widely used in periodontics for its wound healing potential. Two major variations of PRF are the original leukocyteand platelet-rich fibrin (L-PRF) and the modified lowspeed advanced PRF (A-PRF). OBJECTIVES: The aim of the present study was to evaluate and compare the conventional L-PRF protocol and the low-speed A-PRF protocol in terms of angiogenic potential of PRF, using an in vivo chorioallantoic membrane (CAM) assay. MATERIAL AND METHODS: Fifteen fertile Giriraja eggs were procured and after a 3-day incubation period, randomly allotted into 3 groups: control; L-PRF; and A-PRF. A total of 20 mL of blood was collected from systemically healthy male volunteers aged 18-24 years, using a standard protocol. The PRF samples were inoculated on the CAM of the eggs. On the 10th day, the eggs were reopened and photographed. The parameters assessed were the number, length, size, and density of blood vessels, as well as the number of junctions formed. The photographs were analyzed using the ImageJ and ProgRes® CapturePro software. RESULTS: Seven days after inoculation, both the A-PRF and L-PRF groups exhibited significantly better results than the control group in terms of the number (59.20 ±6.61 vs. 48.80 ±5.07 vs. 19.20 ±6.98), length (25,000 ±1,813.10 µm vs. 17,000 ±282.90 µm vs. 8,000 ±184.49 µm), size (230,000 ±15,054.00 µm2 vs. 200,000 ±8,295.27 µm2 vs. 150,000 ±4,105.16 µm2), and density (central: 9,100 ±296.78 vs. 5,370 ±272.42 vs. 1,420 ±564.36; peripheral: 9,094 ±400.14 vs. 3,370 ±479.39 vs. 5,420 ±746.73) of blood vessels, as well as the number of junctions formed (52 ±3.81 vs. 41 ±1.58 vs. 33 ±4.64), respectively. CONCLUSIONS: The angiogenic potential was increased by the exposure to both L-PRF and A-PRF. However, A-PRF demonstrated statistically significant benefits in terms of the number, length, size, and density of blood vessels, as well as the number of junctions formed in comparison with the control and L-PRF groups.

Salvaging the second molar with platelet-rich fibrin and photobiomodulation (970 nm diode laser) following third molar extraction.

Second molars are more susceptible to periodontitis when present adjacent to periodontally hopeless third molars. It is crucial to restore the health of the second molar and to prevent a dry socket after third molar extraction. To ensure complete eradication of infection along with regeneration, mere nonsurgical periodontal therapy might be inadequate. Thus, in this case report, high-level laser therapy (HLLT), advanced-platelet-rich fibrin (A-PRF), and low-level laser therapy (photobiomodulation [PBM]) were adapted to obtain a synergistic effect. HLLT was accomplished for decontamination and clot stabilization following the third molar extraction. Further, A-PRF was placed and irradiated with PBM on 3rd, 7th, 15th, and 21st days, postoperatively. There was reduced clinical probing depth and gain in clinical attachment level with a significant radiographic bone fill distal to second molar at 3 months follow-up. This combined use of HLLT, and PBM along with PRF could be a reliable treatment approach for regeneration, particularly in acute infections.

Augmentation of Peri-implant Keratinized Mucosa Using a Combination of Free Gingival Graft Strip with Xenogeneic Collagen Matrix or Free Gingival Graft Alone: A Randomized Controlled Study.

Purpose: To evaluate the gain in peri-implant keratinized mucosa (KM) using a combination of a free gingival graft (FGG) strip with a xenogeneic collagen matrix (XCM) and compare it to that of an FGG alone. Materials and Methods: This randomized controlled clinical study included a total of 30 patients with a minimal amount of peri-implant KM (≤ 1 mm) in the maxillary and mandibular anterior regions (including the premolars). The study population was divided into two groups using a randomization protocol; group A (n = 15) received a combination of FGG strip and XCM, and group B (n = 15) received FGG only to augment the KM. Clinical parameters included width of KM (WKM) measured at baseline, 1 month, and 6 months; a customized pink esthetic score (PES) measured at baseline and 6 months; and patient morbidity using visual analog scale (VAS) at days 1, 7, and 14 postoperatively. Results: After 1 month, both groups showed statistically significant gain in KM that reduced slightly by the 6-month follow-up but remained statistically significant when compared to baseline. When the gain was compared between the two groups, the difference was not statistically significant. Better esthetic outcomes and lower morbidity were reported in group A compared to group B, and this difference was statistically significant. Conclusions: Within the limitations of the study, it can be concluded that the combination of FGG strip with XCM is a viable alternative to the use of FGG in augmenting peri-implant KM.

A Radiohistographic Analysis of Growth Factor-Mediated Sinus Augmentation in Atrophic Maxillae: A 30-Month Follow-up Study.

A total of 20 atrophic maxillary sinuses were augmented with recombinant human platelet-derived growth factor BB (rhPDGF-BB), alloplast, and bovine xenograft using a direct approach. CBCT imaging was performed at baseline, immediately postoperatively, and at 6 and 30 months postoperatively. A histologic evaluation revealed the bone bridging and bone regenerative efficacy of the graft material. Radiographic evaluation determined the ridge height (H) and volume of the graft (V) to be as 3.02 ± 1.35 mm at baseline (H0), 15.18 ± 2.52 mm (H1) and 1,106.10 ± 398.84 mm3 (V1) immediately postoperatively, 14.79 ± 2.30 mm (H2) and 1,086.95 ± 396.86 mm3 (V2) at 6 months, and 1,058 ± 391.83 mm3 (V3) at 30 months, with a significant gain in the residual ridge height at 6 months and no significant loss or gain in sinus volume postoperatively.

Autologous tooth bone graft block compared with advanced platelet-rich fibrin in alveolar ridge preservation: A clinico-radiographic study.

Objectives: To determine the clinico-radiographic efficiency of partially demineralized dentin matrix block (PDDM block), a mixture of PDDM with advanced-platelet-rich fibrin+ (A-PRF+) and injectable platelet-rich fibrin versus A-PRF+ alone in alveolar socket preservation. Materials and Methods: Sixteen molar teeth indicated for extraction were randomly assigned into two groups. For the test group, sockets were packed with PDDM block and control group, with A-PRF+ plug alone. Clinical and radiographic cone-beam computed tomography methods were used to assess the horizontal and vertical ridge dimensional changes at baseline and 4 months. Results: Clinically, the mid buccal and palatal crestal height (10.25 ± 0.86 and 9.75 ± 0.28 mm) and alveolar ridge width (11.37 ± 0.25 mm) were significantly higher in the test group as compared to the control group, 4 months after tooth extraction (P < 0.01). Radiographically, there was improved apposition and nonsignificant resorption for the test group in ridge height and width, whereas statistically significant higher resorption was seen in the control group at 4 months. Conclusion: The application of the PDDM block demonstrated efficacy in maintaining the dimensions of the extraction socket when compared to A-PRF+ alone. This autologous and immune-free regenerative biomaterial is widely obtainable, offering a glimpse into the potential of next-generation biofuels for regeneration.

Second-generation Liquid Platelet Concentrates: A Literature Review.

Liquid or injectable platelet-rich fibrin (PRF) is a second-generation platelet concentrate that is completely autologous and free of external additives, like bovine thrombin and calcium chloride. Additionally, it is the only one to be obtained in a liquid form among the second-generation platelet concentrates. This allows for wide applications such as maximizing injections or mixing with biomaterials such as bone grafts or antibiotics. Since it was first introduced in 2015, several modifications of the original protocol have been proposed which aim at maximizing its biological and mechanical properties. This includes changes in centrifugation speed, time, and so on. The aim of this review is to summarize the various modifications of the injectable/liquid formation of PRF as well as to discuss the potential applications and future research direction.

Second-Generation Liquid Platelet Concentrates: A Potential Boon for Regenerative Dentistry.

Platelet concentrates have seen significant advancement in the field of biological surgical wound additives. The focus is now on second-generation platelet concentrates, which are completely autologous with no external additives. Unlike other platelet concentrates, liquid or injectable platelet-rich fibrin (i-PRF) is the only one that is obtained in a liquid form. This property widens the horizons for its application to virtually any medical field, including many uses in dentistry. Over the past several years, studies have proposed different variations of i-PRF, such as changes to the protocol by varying centrifugation time, g-force, and other factors. The liquid or injectable form of PRF also allows for other modifications, such as the addition of various biomaterials. This article reviews the current evidence and advancements regarding i-PRF and its potential future applications.

Clinicoradiographic evaluation of advanced-platelet rich fibrin block (A PRF + i PRF + nanohydroxyapatite) compared to nanohydroxyapatite alone in the management of periodontal intrabony defects.

Background: Several bone grafting formulations have been given clinically acceptable outcomes in treating intrabony defects. Platelet rich fibrin (PRF), an autologous platelet concentrate holds potential to be used for regenerative treatment. The purpose of this study was to evaluate clinical and radiographic outcomes in periodontal intrabony defects treated with advanced-PRF block (A PRF + i PRF + nanohydroxyapatite [nHA]) compared to nHA alone. Methods: Twenty-eight sites in chronic periodontitis patients having probing pocket depth (PPD) ≥6 mm and 3 walled intrabony defects (depth of ≥3 mm) were selected, randomly allotted into two groups: Group A was treated with A-PRF block and Group B with nHA (Sybograf™). Clinical parameters including plaque index (PI), gingival index (GI), PPD, relative attachment level (RAL) and radiographically linear and volumetric defect fill were assessed using cone beam computed tomography at baseline and 6 months postoperatively. Results: Intragroup comparison using paired t-test and intergroup comparison using unpaired t-test was done. Group A demonstrated significantly higher reduction in PPD and gain in RAL when compared to Group B (P ≤ 0.05) at the end of 6 months. Similarly gain in bone volume was greater in Group A (0.1 ± 0.05) as compared to Group B (0.04 ± 0.02) (P ≤ 0.05). Conclusion: Advanced-PRF block showed significant clinical and radiographic improvement as compared to nHA alone which depicts that, it may be an ideal graft to be used for the treatment of periodontal intrabony defects.

Efficacy of antimicrobial photodynamic therapy on the tongue surface in the management of halitosis - A real-time polymerase chain reaction analysis.

AIM: To evaluate the additional effect of a single session of antimicrobial photodynamic therapy (aPDT) on the tongue as an adjunct to scaling and root planing (SRP) on most common volatile sulfur-producing microbes such as Porphyromonas gingivalis (Pg), Treponema denticola (Td) and Fusobacterium nucleatum (Fn) on 3rd, 7th and 14th day postoperatively using RT-PCR analysis. METHOD AND MATERIALS: Twenty-four patients of either sex, presented with moderate to severe malodor, detected by a portable breath checker (Tanita®) were considered for the study and assigned to group A & B. Scaling and root planning was performed in both the groups, followed by photodynamic therapy on the tongue surface in group A. One percent methylene blue photosensitizer was applied on the middle and posterior thirds of the dorsum of the tongue and irradiated in continuous mode at six different points for 90 s at each point. RESULTS: A significant reduction in Halimeter scores throughout the study period was observed. A significant reduction in the tongue coating score on 3rd and 7th day and the total count of Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn) on 7th and 14th day was seen in group A (p ≤ 0.05). However, the mean reduction in Treponema denticola (Td) was non-significant in both the groups but a greater fall in the total count was seen in group A compared to group B on all the days (p ≥ 0.05). CONCLUSION: Within the limitations of the study, it was concluded that photodynamic therapy on the tongue along with scaling and root planing was effective in the reduction of malodour and the total count of bacteria responsible for the same. Long-term clinical trials are required to further substantiate the effectiveness of this technique.