Gulnihal Eren | Ege University (original) (raw)

Papers by Gulnihal Eren

ÖZ: Günümüzde çeşitli tekniklerle elde edilen farklı trombosit konsantrasyonları bulunmaktadır. B... more ÖZ: Günümüzde çeşitli tekniklerle elde edilen farklı trombosit konsantrasyonları bulunmaktadır. Benzer isimlerle anılsa bile, bu konsantrasyonların biyolojik içerikleri farklıdır. Lökosit ve trombositten zengin fibrin (L-TZF), kan kaynaklı trombosit konsantrasyonları arasında en son geliştirilenidir. Herhangi bir antikoagülan ajana gerek duyulmadan hazırlanan L-TZF'nin eldesi kolaydır. L-TZF'nin biyolojisinde her ne kadar trombosit kaynaklı büyüme faktörleri önemli bir rol oynasa da, fibrin organizasyonu ve lökosit içeriği de diğer iki anahtar değişkenini oluşturur. Bu nedenle L-TZF, içeriğinde bulunan büyüme faktörleri ve hücreler sayesinde doğal yara iyileşmesini olumlu yönde etkiler. Yumuşak doku ve kemik iyileşmesi üzerindeki olumlu özellikleri nedeniyle günümüzde L-TZF'nin diş hekimliği alanında kul-lanım sıklığı giderek artmaktadır. Anahtar kelimeler: Trombositten zengin fibrin, yara iyileşmesi, büyüme faktörü, sitokin, rejenerasyon ABSTRACT Several platelet concentrates are avaliable in different techniques; however, their biological contents vary from one to another. Leukocyte platelet-rich fibrin (L-PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. Although platelet-derived growth factors play an important role in biology of PRF, fibrin organization and the leukocyte content are other two key variables. Due to the growth factor and cell content, L-PRF has a positive effect on natural wound healing. Frequency of L-PRF usage in dentistry is increasing, because of its positive effects on soft tissue and bone healing.

Background and Objective: The objective of this study was to evaluate the levels of MMP-8, MMP-9... more Background and Objective: The objective of this study was to evaluate the levels of MMP-8, MMP-9, TIMP-1 and interleukin-1beta (IL-1b) in gingival crevicular fluid during the early and late stages of healing in gingival recession sites treated with coronally advanced flap plus platelet-rich fibrin (CAF+PRF) compared with CAF plus connective tissue graft (CAF+CTG).
Material and Methods: Twenty-four nonsmoking patients with Miller Class I or Class II localized gingival recession defects in bilateral sites received treatment with either CAF+PRF (PRF group) or CAF+CTG (CTG group). Gingival crevicular fluid samples were collected at baseline and at 10 d and 1 mo, 3 mo and 6 mo after surgery. The levels of MMP-8, MMP-9, TIMP-1 and IL-1b in gingival crevicular fluid were measured using a time-resolved immunofluorometric assay and ELISAs.
Results: Gingival crevicular fluid levels of IL-1b were significantly elevated in the CTG group at 10 d compared with baseline (p < 0.05). At 10 d after surgery, the levels of TIMP-1 in gingival crevicular fluid showed a significant decrease in the CTG group compared with the PRF group (p < 0.05). The levels of IL-1b and MMP-8 in gingival crevicular fluid were significantly lower in the PRF group than in the CTG group at 10 d (p < 0.05). No significant differences were found in all clini- cal and biochemical parameters at 1, 3, and 6 mo between study groups (p > 0.05).
Conclusion: Root coverage with CAF+PRF has a significant effect on increasing gingival crevicular fluid TIMP-1 levels and suppressing gingival crevicular fluid MMP-8 and IL-b levels at 10 d. Gingival crevicular fluid levels of MMP-8, MMP-9, TIMP-1 and IL-1b did not seem to be affected by the technique at later phases of wound healing.

Background/aim: The effect of smoking on inflammatory biomarkers in gingival crevicular fluid (G... more Background/aim: The effect of smoking on inflammatory biomarkers in gingival crevicular fluid (GCF) is well established in the presence of periodontal inflammation. However, it is not clear if smoking has an influence on matrix metalloproteinase (MMP) and growth factor levels in the GCF of periodontally healthy subjects. The aim of this study was to investigate GCF levels of MMP-1, MMP- 8, transforming growth factor (TGF)-β1, platelet-derived growth factor (PDGF)-AB, and vascular endothelial growth factor (VEGF) in smoking versus nonsmoking periodontally healthy subjects.
Materials and methods: Thirty-two periodontally healthy subjects were included in this study. Probing depths, bleeding on probing, and plaque index was assessed. GCF levels of MMP-1, MMP-8, TGF-β1, PDGF-AB, and VEGF were analyzed by enzyme-linked immunosorbent assay.
Results: No significant differences were observed in the distribution of demographic data between study groups. GCF total amount of PDGF-AB was significantly lower in smokers compared to nonsmokers (P = 0.014). Total amount of GCF MMP-1, MMP-8, TGF-β1, and VEGF levels were similar in both study groups (P = 0.022).
Conclusion: Smoking has the effect of decreasing GCF PDGF-AB while it does not affect GCF MMP-1, MMP-8, TGF-β1, and VEGF in periodontally healthy subjects. Since increased levels of these molecules are involved in periodontal breakdown, our findings may emphasize the importance for maintenance of periodontal health in smokers.

Abstract Platelet-rich fibrin (PRF) has a controlled release of growth factors due to the fibrin ... more Abstract
Platelet-rich fibrin (PRF) has a controlled release of growth factors due to the fibrin matrix structure. Different centrifugation protocols were suggested for PRF preparation. Since the derivation method of PRF can alter its contents, in the present study it is aimed to investigate the cell contents and transforming growth factor beta-1 (TGF-β1), platelet-derived growth factor (PDGF-AB), vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-1 and-8 release from experimental PRF-type membranes obtained with different centrifugation times at 400 gravity. Three blood samples were collected from 20 healthy non-smoker volunteers. One tube was used for whole blood analyses. The other two tubes were centrifuged at 400 g for 10 minutes (group A) or 12 minutes (group B). Each experimental PRF-type membrane was placed in Dulbecco’s Modified Eagle’s Medium (DMEM)and at 1, 24 and 72 hours, TGF-β1, PDGF-AB, VEGF, MMP-1 and -8 release amounts were analysed by enzyme-linked immunosorbent assay (ELISA). The blood cell count of membranes was determined by subtracting plasma supernatant and red blood cell (RBC) mixture from the whole blood cell counts. At 72 hours, the VEGF level of group B was statistically higher than that of group A (p = 0.040). The centrifugation time was not found to influence the release of other growth factors, enzymes and cell counts. Within the limits of the present study, it might be suggested that centrifugation time at a constant gravity has a significant effect on the VEGF levels released from experimental PRF-type membrane. It can be concluded that due to the importance of VEGF in the tissue healing process, membranes obtained at 12-minute centrifugation time may show a superior potential in wound healing.

Abstract Objective The aim of this study was to evaluate histologically the following treatment o... more Abstract
Objective The aim of this study was to evaluate histologically the following treatment of bilateral localized gingival recessions with coronally advanced flap (CAF) combined with platelet-rich fibrin (PRF) or subepithelial connective tissue graft (SCTG). Materials and methods Tissue samples were harvested from 14 subjects either 1 or 6 months after the surgeries. The 2-mm punch biopsies were obtained from the mid-portion of the grafted sites. Neutral buffered formalin fixed, paraffin- embedded 5-μm thick tissue sections were stained with hema- toxylin eosin and Masson’s trichrome in order to analyze the collagen framework, epithelium thickness and rete-peg length. Multiple sequential sections were cut from paraffin-embedded blocks of tissue and immunohistochemically prepared for de- tection of vascular endothelial growth factor, CD31 and CD34, for the assessment of vascularization.
Results Rete peg formation was significantly increased in the sites treated with PRF compared to the SCTG group after 6 months (p < 0.05). On the contrary, the number of vessels was increased in the SCTG group compared to the PRF group after 6 months (p < 0.05). No statistically significant differ- ences were observed in the collagen density. Staining intensity of CD31 increased in submucosal area of PRF group than SCTG group after 1 month. Higher staining intensity of CD34 was observed in the submucosal area of PRF group compared with SCTG group after 6 months.
Conclusions The results of the present study suggest that in histological evaluation because of its biological compounds, PRF results earlier vessel formation and tissue maturation compared to connective tissue graft.
Clinical relevance PRF regulated the vascular response asso- ciated with an earlier wound healing.

Determining the oral health status and oral hygiene habits of the elderly Background: Oral and pe... more Determining the oral health status and oral hygiene habits of the elderly Background: Oral and periodontal health status of the elderly should be known, in order to plan protective and essential treatment procedures. The aim of this present study is to determine the periodontal status, prevalence of caries and oral hygiene habits of elderly living in residential homes in İzmir, Turkey.

Abstract Objectives The aim of this study is to evaluate the clinical efficacy of platelet-rich f... more Abstract
Objectives The aim of this study is to evaluate the clinical efficacy of platelet-rich fibrin (PRF) in combination with coronally advanced flap (CAF) in the treatment of localized gingival recessions.
Materials and methods Twenty-two patients with localized gingival recession defects (Miller I, II) participated in this split-mouth trial. Forty-four defects received either CAF+ PRF (test) or CAF with subepithelial connective tissue graft (SCTG) (control). Gingival recession depth (RD), gingival recession width (RW), keratinized tissue width (KTW), reces- sion area (RA), probing depth (PD), clinical attachment level (CAL) and gingival thickness (GT) were evaluated at baseline and 6 months. RD, RW, RA and KTW were calculated on standardized photographs with a computer image analysis program.
Results Percentage of root coverage in test group was 92.7 % and in control group was 94.2 % (p>0.05). Percentage of complete root coverage of the test and control groups was 72.7 and 77.3 %, respectively (p>0.05). KTW and GT were increased in both groups from baseline to 6 months (p<0.001), but there was no statistically significant difference between treatment groups (p>0.05).
Conclusion Within the limits of the present study, it can be concluded that localized gingival recessions could be success- fully treated with CAF+PRF as well as CAF+SCTG. The digital measuring method provided high accuracy and preci- sion in the evaluation of treatment outcomes after both surgi- cal procedures.
Clinical relevance PRF might be suggested as an alternative to SCTG for the treatment of localized gingival recessions.

Introduction: Subepithelial connective tissue graft (SCTG) þ coronally advanced flap (CAF) has be... more Introduction: Subepithelial connective tissue graft (SCTG) þ coronally advanced flap (CAF) has been suggested as the most predictable technique for treatment of recession defects. However, the SCTG technique necessitates a second surgical site and increases the risk of morbidity linked with harvesting the autogenous palatal donor mucosa. Platelet-rich fibrin (PRF) has been shown to accelerate soft-tissue healing. The use of PRF in treatment of gingival recessions eliminates the requirement of a donor site. The aim of this case report is to evaluate the clinical effectiveness of the CAFþPRF combined technique and CAFþSCTG in the treatment of bilateral gingival recessions. Case Presentation: The surgical treatment of a 23-year-old female patient with bilateral gingival recessions in maxillary cuspids is discussed in this case report. Sites were randomly assigned to CAFþPRF (test) or CAFþSCTG (control) sites. Clinical periodontal parameters were recorded and clinical photographs were taken at baseline; 1, 3, and 6 months; and 1 year. The recession area was analyzed with a digital image analysis program. In addition, gingival thickness was evaluated at baseline and at 1 year. Conclusions: Root coverage amount, gingival thickness, and keratinized tissue width were improved in both sites. The outcomes remained stable for 1 year. CAFþPRF presents an alternative to CAFþSCTG in the treatment of gingival recessions. The PRF method is practical and simple to perform. Additionally, PRF seems to be superior to SCTG since it eliminates the requirement of a donor site. Clin Adv Periodontics 2012;2:154-160.