Sustainability and Release Pattern of Growth Factors from Bone Grafts Prepared with Platelet-Rich Fibrin.

BACKGROUND: Platelet-rich fibrin (PRF) is used to prepare "sticky bone" by combining it with bone-graft material. The present study investigated the ability of different bone grafts to absorb growth factors from the PRF and release them over time. METHODS: Human blood was collected from 10 healthy volunteers for liquid PRF preparation. Bovine bone, allograft (mineralized and demineralized), and synthetic bone were each mixed with the PRF to prepare a sticky bone. All sticky bone samples were incubated for up to 4 days and the absorption and release pattern kinetics of two selective growth factors within the PRF (Platelet-Derived Growth Factor and bone morphogenetic protein 2) were quantified with immunofluorescence staining and ELISA. RESULTS: All the tested bone graft materials adsorbed the examined growth factors from the PRF. ß-TCP showed the highest adsorption levels, followed by the xenograft, and the allografts showed the lowest adsorption levels. Furthermore, PDGF showed a fast release pattern from the grafts, whereas BMP2 was released at a later stage. Similar to the adsorption pattern, the ß-TCP and xenograft were better able to sustain the release of the PRF growth factors from the graft than the allografts. CONCLUSIONS: The adsorption of PDGF and BMP2 differ between graft materials, with superior results for ßTCP, followed by xenograft and lastly the allograft materials.

Tranexamic acid integrated into platelet-rich fibrin produces a robust and resilient antihemorrhagic biological agent: a human cohort study.

OBJECTIVE: To investigate the incorporation of the antifibrinolytic agent tranexamic acid (TA) during platelet-rich fibrin (PRF) formation to produce a robust fibrin agent with procoagulation properties. STUDY DESIGN: Blood from healthy volunteers was collected. Into 3 tubes, TA was immediately added in 1-mL, 0.4-mL, and 0.2-mL volumes, and the fourth tube was without additions. After PRF preparation, the clots were weighed in their raw (clot) and membrane forms. PRF physical properties were analyzed using a universal testing system (Instron). Protein and TA levels in the PRF were analyzed using a bicinchoninic acid assay and a ferric chloride assay, respectively. RESULTS: The addition of TA to PRF led to a robust weight compared with sham control. PRF weight was greater in females in all tested groups. The addition of TA also led to greater resilience to tears, especially at 1-mL TA addition to the blood. Furthermore, TA addition led to a greater value of total protein within the PRF and entrapment of TA in the PRF. CONCLUSIONS: Addition of TA to a PRF preparation leads to robust PRF with greater protein levels and the amalgamation of TA into the PRF. Such an agent may enhance the beneficial properties of PRF and attribute procoagulation properties to it.

Knowledge and Opinion of Internists and Gynecologists Physicians on Periodontal Medicine.

PURPOSE: To evaluate the knowledge, opinions, and behaviours of physicians in the field of internal medicine and gynecology regarding periodontal disease and its systemic implications. METHODS: A questionnaire was distributed by hand and via e-mail to internists and gynecologists working in hospitals and community clinics. The questionnaires included items regarding personal and professional status, subject-related characteristics, dental history and knowledge in periodontal medicine. All completed questionnaires were reviewed and analysed according to discipline and personal experience. Statistical differences were tested using the chi-squared analysis. RESULTS: A total of 97 questionnaires were reviewed and included 56 internists and 41 gynecologists. The mean age was 39.7 years (range 29-82) and the percentage of females was 54%. Overall, general knowledge regarding periodontitis differed significantly between internists and gynecologists (80% vs 32% correct answers per group, respectively). Nearly 60% of responders (both internists and gynecologists) knew the correct cause of periodontal disease. Although half of the responders had personal experience in the field of periodontology, this experience was not noticeable regarding their knowledge in periodontal medicine. The majority of responders (58%) agreed that there is a need for more periodontal education in general medicine. CONCLUSIONS: The present study indicates a clear lack of knowledge of both internists and gynecologists regarding periodontitis and its systemic complications. Personal periodontal experience did not change the degree of familiarity with periodontal medicine.

Microbial accumulation on different suture materials following oral surgery: a randomized controlled study.

BACKGROUND: The aim of the study was to compare bacterial accumulation on different suture materials following oral surgery. METHODS: Patients scheduled for implant or periodontal surgery were included in the study. Upon flap closure, four different sutures were placed in a randomized sequence-silk, coated polyglactin, nylon, and polyester. Ten days following surgery, the sutures were removed and incubated in aerobic as well as anaerobic conditions for 7 days and colony-forming units (CFUs) were calculated. Association between bacterial accumulation and periodontal diagnosis, type of surgery, and antibiotic treatment were also tested. RESULTS: All sutures in all patients were found to contain bacteria. Overall, nylon sutures showed significantly lower CFU levels compared to silk, coated polyglactin, and polyester sutures. The type of surgery (implant vs. periodontal surgery) did not significantly influence bacterial accumulation. Also, periodontal diagnosis had little impact on CFU counts. Interestingly, post-surgical antibiotic treatment also had only a minor effect on bacterial accumulation on the various sutures. DISCUSSION: The results indicate that the monofilamentous nylon sutures showed less microbial accumulation than the other tested materials that were all braided. This effect may be due to material qualities as well as suture macrostructure. Type of surgery, periodontal diagnosis, and antibiotic consumption have little effect on bacterial accumulation of sutures. CLINICAL RELEVANCE: The study provides the microbial profile of commonly used sutures and may assist in suture selection during clinical procedures.

Mucosal pH, dental findings, and salivary composition in pediatric liver transplant recipients.

BACKGROUND: Oral health and dental maintenance have become part of the standard of care for pediatric liver transplant recipients. These individuals tend to suffer particularly from dental problems, such as gingival enlargement, gingivitis, poor oral hygiene, dental hypoplasia, and caries. Saliva composition influences oral hygiene and disease states. We investigated saliva composition and its association with the oral health of young recipients of liver transplants. METHODS: In 70 patients, 36 liver transplant recipients (ages 2-23 years) and 34 healthy controls (ages 4-21 years), we measured the following variables: (a) oral hygiene, (b) gingival inflammation, (c) caries status, (d) dental calculus formation, (e) oral mucosal pH, and (f) salivary protein composition. RESULTS: Lower mean decayed, missing, and filled teeth index (P=0.0038), higher mean gingival index (P=0.0001), and higher mean calculus score (P=0.003) were found in the transplanted study group compared with the control. The mean mucosal pH for seven intraoral sites was higher in the transplant group (P=0.0006). The median salivary albumin concentration was significantly lower in the transplant group (P=0.01), as was the median salivary albumin/total protein ratio (P=0.0002). CONCLUSIONS: In post-liver transplant pediatric recipients, low incidence of caries, together with high incidence of dental calculus, could be attributed to elevated oral mucosal pH. Salivary albumin and immunoglobulin A levels were relatively low in these patients. Clinicians should pay particular attention to the oral health and dental care of liver transplanted children.