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Öğe Dentofacial changes from fan-type rapid maxillary expansion vs traditional rapid maxillary expansion in early mixed dentition : a prospective clinical trial(E H Angle Education Research Foundation, Inc, 2013) Çörekçi, Bayram; Göyenç, Yaşar B.Objective: To test the null hypothesis that there is no difference between the effects of fan-type rapid (FRME) and rapid maxillary expansion (RME) used with an acrylic bonded expansion appliance on dentofacial structures in early occlusal stages. Materials and Methods: This was a prospective clinical trial. The FRME group had an anterior constricted maxillary width with a normal intermolar width, and the RME group had bilateral constricted maxillary width. The FRME group consisted of 20 patients (mean age, 8.96 +/- 1.19 years), and the RME group consisted of 22 patients (mean age, 8.69 +/- 0.66 years). Lateral and frontal cephalometric radiographs and dental casts were taken before and after expansion and 3 months after completing treatment for each patient. The data were compared using repeated-measures analysis of variance. The paired-samples t-test was used to evaluate treatment and retention effects, and the independent samples t-test was used to consider the differences between the two groups. Results: The maxilla moved downward and forward in both groups. The nasal cavity and maxillary width were expanded more in the RME group, and there were only a few relapses in this group during the retention period. There was significant labial tipping of the upper incisors in the FRME expansion group. The expansion of intercanine width was similar in both groups, but the expansion of intermolar width was significantly greater in the RME group. Conclusion: The null hypothesis was rejected. There was a difference between the effects of FRME and RME used with an acrylic bonded expansion appliance on dentofacial structures in the early occlusal stages.Öğe Does stinging nettle (urtica dioica) have an effect on bone formation in the expanded inter-premaxillary suture?(Pergamon-Elsevier Science Ltd, 2016) Irgın, Celal; Çörekçi, Bayram; Ozan, Fatih; Halıcıoğlu, Koray; Toptaş, Orçun; Yıldırım, Arzu Birinci; Türker, Arzu; Yılmaz, FahriObjective: To determine whether systemically given stinging nettle (SN) has an effect on bone formation in response to expansion of the rat inter-premaxillary suture. Materials and methods: A total of 28 male Wistar albino rats were randomly divided into 4 equal groups: control (C), only expansion (OE), SN extract given only during the expansion and retention periods (SN group; a total of 17 days), and SN extract given during the nursery phase before expansion (a period of 40 days) and during the expansion and retention periods (N + SN group; a total of 57 days). After the 5-day expansion period was completed, the rats in the OE, SN, and N + SN groups underwent 12 days of mechanical retention, after which they were sacrificed, and their premaxilla were dissected and fixed. A histologic evaluation was done to determine the number of osteoblasts, osteoclasts, and capillaries, as well as the number and intensity of inflammatory cells and new bone formation. Results: Statistically significant differences were found between the groups in all histologic parameters except the ratio of intensities of inflammatory cells. New bone formation and the number of capillaries were significantly higher in the SN groups than in the other groups. The statistical analysis also showed that the numbers of osteoblasts, osteoclasts, and capillaries were highest in the N + SN group. Conclusion: Systemic administration of SN may be effective in accelerating new bone formation and reducing inflammation in the maxillary expansion procedure. It may also be beneficial in preventing relapse after the expansion procedure. (C) 2016 Elsevier Ltd. All rights reserved.Öğe Effect of Royal Jelly on new bone formation in rapid maxillary expansion in rats(Medicina Oral S L, 2015) Özan, Fatih; Çörekçi, Bayram; Toptaş, Orçun; Halıcıoğlu, Koray; Irgın, Celal; Yılmaz, Fahri; Hezenci, YasinBackground: The aim of this study was to evaluate the effects of long and short term systemic usage of royal jelly on bone formation in the expanded maxillary suture in a rat model. Material and Methods: Twenty eight Wistar albino rats were randomly divided into 4 equal groups: Control (C); Only Expansion (OE), Royal Jelly (RJ) group, Royal Jelly was given to rats by oral gavage only during the expansion and retention period; Royal Jelly plus Nursery (RJN) group, Royal Jelly was given to rats by oral gavage during their nursery phase of 40 days and during the retention period. After the 5 day expansion period was completed, the rats underwent 12 days of mechanical retention. All rats were sacrificed in same time. Histological examination was performed to determine the number of osteoclasts, number of osteoblasts, number of capillaries, inflammatory cell infiltration, and new bone formation. Results: New bone formation, number of osteoclasts, number of osteoblasts, and the number of capillaries in the expanded maxillary sutures were higher in the RJ and RJN groups than in the other groups. Statistical analysis also demonstrated that new bone formation and the number of osteoblasts was also highest in the RJN group. Conclusions: The systemic administration of Royal Jelly in conjunction with rapid maxillary expansion may increase the quality of regenerated bone.Öğe Effect of St John's Wort on bone formation in the orthopaedically expanded premaxillary suture in rats : a histological study(Oxford Univ Press, 2015) Halıcıoğlu, Koray; Çörekçi, Bayram; Akkaş, İsmail; Irgın, Celal; Özan, Fatih; Yılmaz, Fahri; Türker, ArzuBackground/Objective: The aim of this study was to investigate the effect of systemic St John's wort (Hypericum perforatum) on bone formation in the expanded premaxillary suture in rats. Materials/Methods: A total of 28 rats were randomly divided into four groups of equal numbers: control (C); only expansion (OE); St John's wort extract given only during the expansion and retention period (a total of 17 days; SJW group); and St John's wort extract given during the nursery phase before expansion (a period of 40 days), and during the expansion and retention periods (a total of 57 days; N + SJW group). After the 5 day expansion period was completed, the rats in the OE, SJW, and N + SJW groups underwent 12 days of mechanical retention, following which they were killed, and their premaxilla dissected and fixed. Histological examination was performed to determine the number of osteoclasts and capillaries, as well as the number of osteoblasts, inflammatory cell infiltration, and the amount of new bone formation. Results: Statistical analysis showed that the number of osteoclasts and capillaries, and the inflammatory cell infiltration, as well as new bone formation, were higher in the SJW and N + SJW groups than in the other groups. However, statistical analysis demonstrated that among these two groups, all parameters, with the exception of the number of capillaries, were higher in the N + SJW group than the SJW group. Conclusions/Implications: Although more effective in long-term usage, systemic use of St John's wort hastens new bone regeneration at the premaxillary suture and may help prevent relapse after expansion.Öğe Effects of contemporary orthodontic composites on tooth color following short-term fixed orthodontic treatment: A controlled clinical study(2015) Çörekçi, Bayram; Toy, Ebubekir; Öztürk, Fırat; Malkoç, Sıddık; Öztürk, BoraBackground/aim: To determine the color alterations of natural teeth associated with different orthodontic composites used in comprehensive short-term treatment. Materials and methods: Twenty-two patients were treated with fixed appliances and 22 untreated subjects were also evaluated. Lower incisors were bonded with different orthodontic composites: 42 with Grengloo, 41 with Light Bond, 31 with Kurasper F, and 32 with Transbond XT. The color parameters of the Commission Internationale de l’Eclairage (CIE) were measured for each tooth with a spectrophotometer. Color assessment in relation to time, adhesive material, and their interaction was made with 2-way mixed analysis of variance (ANOVA) and 1-way ANOVA for the color differences (∆E*). Further analyses were done using Tukey’s honestly significant difference tests and paired-samples t-tests. Results: The color of teeth was affected by treatment. The mean L* and a* values increased, whereas the mean b* values decreased. Total color differences of teeth demonstrated visible color changes clinically after treatment, ranging from 1.12 to 3.34 ∆E units. However, there were no significant differences for color of enamel. Conclusion: Teeth may be discolored with fixed appliances during treatment. Moreover, contemporary orthodontic composites have similar effects of enamel discoloration.Öğe Effects of plasma-emulating light emitting diode (LED) versus conventional LED on cytotoxic effects of orthodontic cements as a function of polymerization capacity(Sage Publications Ltd, 2014) Çörekçi, Bayram; Halıcıoğlu, Koray; Irgın, Celal; Hezenci, Yasin; Yavuz, Muhsine ZeynepObjectives: The study was aimed at evaluating, in vitro, cytotoxicity of four resin-based orthodontic cements (RBOC) as a function of degree of conversion (DC) and the light curing unit (LCU) employed on mouse fibroblast (L929). Materials and Methods: Nine samples were manufactured for each group of cements using plasma-emulating light-emitting diode (LED) and conventional LED. Toxicity was assessed by immersing four specimens to culture medium (24 h/37 degrees C) for extracting residual monomer or cytotoxic substance. Cell mitochondrial activity of L929 cell was evaluated using methyl tetrazolium (MTT) test. DC was evaluated by Fourier transform infrared spectroscopy for five samples. Results: Cements, LCUs, and interaction between cements and LCUs were found to play a statistically significant role in cytotoxicity (p < 0.0001). Opal band cement (OPAL) plasma LED was found noncytotoxic (90-100% cell viability). The other RBOC-LCU combinations were slightly cytotoxic (60-90% cell viability). Cements (p < 0.01) and LCUs (p < 0.05) had a statistically significant effect on DC. Conversely, interaction between cement and LCU had no statistically significant role on DC (p > 0.05). OPAL plasma LED displayed the highest levels of DC. The correlations between cell viability and DC were positive for three RBOCs. Conclusion: Therefore, high-intensity LCUs can be said to efficiently affect polymerization, so higher DC rates may achieve higher cell viability rates. Clinical Relevance: Cements and LCUs must be matched to each another to result in higher DC and maximal biocompatibility. Dual cure systems presented relatively high cell survival and higher DC, thus expressing superior to single-cure systems with plasma LED.Öğe Effects of plasma-emulating light-emitting diode (LED) versus conventional LED on cytotoxic effects and polymerization capacity of orthodontic composites(Sage Publications Ltd, 2014) Çörekçi, Bayram; Irgın, Celal; Halıcıoğlu, Koray; Dursun, Saffet; Yavuz, Muhsine ZeynepObjectives: The aim of this study was to evaluate, the cytotoxicity of orthodontic composites in vitro as a function of degree of conversion (DC) and the light curing units (LCU) employed on mouse fibroblast (L929). Materials and Methods: Cured samples of the composites Light bond (Reliance Orthodontic Products, Itasca, Illinois, USA), Ortho bracket paste (Bisco, Schaumburg, Illinois, USA), Opal bond MV (OPAL, South Jordan, Utah, USA), and Transbond XT (3M, Monrovia, California, USA) were prepared. Polymerization was performed with two LCUs: VALO Ortho (Ultradent, South Jordan, Utah, USA) is a third-generation LCU and Elipar S I 0 (3M, USA) is a second-generation LCU. Four samples were immersed in cell culture medium to obtain composite extracts. After incubation of L929 cell cultures with the extracts obtained, cytotoxicity was determined using the methyl tetrazolium test. Fourier transform infrared spectroscopy (FTIR) was used to evaluate DC for five samples. A multivariate analysis of variance (ANOVA), two-way ANOVA, and Tukey's honestly significant difference test were utilized for statistical analyses. Results: Cytotoxicity and DC of all tested composites (p < 0.001) and the interaction between composites and LCUs < 0.01) were significantly different. LCUs had no significant influence on the cytotoxicity and DC of composite materials (p > 0.05). The correlations between cell viability and DC were positive for three composites but statistically insignificant. Conclusion: Composites and LCUs must be matched with one another to result in satisfactory maximal biocompatibility and DC. Opal Bond plasma light-emitting diode combination was a better choice for cell viability. Three composites showed a positive correlation between cytotoxicity and DC. Therefore high-intensity LCUs can be said to efficiently affect polymerization, and so, higher DC rates may achieve higher cell viability rates.Öğe Effects of staining solutions on the discoloration of orthodontic adhesives: An in-vitro study(Mosby-Elsevier, 2010) Çörekçi, Bayram; Irgın, Celal; Malkoç, Sıddık; Öztürk, BoraIntroduction: Our aim was to evaluate the effects of staining solutions on the discoloration of orthodontic adhesives. Methods: Six orthodontic adhesives were investigated (Transbond XT [3M Unitek, Monrovia, Calif, USA], Heliosit Orthodontic [Ivoclar Vivadent, Liectenstein], Light Bond [Reliance Orthodontic Products, Itasca, IL, USA], Bisco Ortho [Bisco, Schamburg, IL, USA], Quick Cure [Reliance Orthodontic Products, Itasca, IL, USA], and Filtek Supreme XT [3M ESPE, St Paul, Minn, USA]), and 5 beverages (tea, cola, coffee, red wine, and yogurt). Sixty specimens were prepared. Five specimens from each group were stored in each of the 5 staining solutions. The 5 remaining specimens from each group served as the controls and were stored in distilled water. The specimens were immersed in staining solutions and water at 37 degrees C +/- 1 degrees C for 5 days. The test period was 25 days. Before and after the test period, color measurements were carried out with a spectrophotometer, and color changes (Delta E*) were calculated. Statistical differences were evaluated by using analysis of variance (ANOVA) and the Tukey HSD tests. Results: Adhesive materials, staining agents, and their interactions were found to play statistically significant roles (P <0.001) in color changes. Among the adhesive materials, the Light Bond water control group consistently showed the lowest Delta E* value for all materials, and the Filtek Supreme XT group showed the highest Delta E* value for all materials. After the in-vitro experimental process for staining solutions and water, unsatisfactory color stability was observed for the conventional adhesive systems except for Light Bond, Transbond XT, and Bisco Ortho water control group (Delta E* >3.7), respectively. Conclusions: In esthetically critical areas, discoloration of adhesive materials for fixed orthodontics can cause patient dissatisfaction. Orthodontic composites will discolor from staining beverages during their lifespan. (Am J Orthod Dentofacial Orthop 2010;138:741-6)Öğe Isolated oligodontia in monozygotic twins(2013) Halıcıoğlu, Koray; Şahin, Hakan; Çörekçi, Bayram; Irgın, Celal; Toptaş, OrçunThis case report defines a case of isolated oligodontia of 9 and 10 permanent teeth in 9-year-old monozygotic twin sisters and gives information about the possible genetic and environmental etiology, related dental anomalies and treatment options. The twins have a negative family history of hypodontia and oligodontia in their parents, as well as their paternal and maternal grandmothers and first cousins. No other dental anomalies could be detected in either of the twins. With the occurrence of similarly located tooth agenesis, except for one tooth, in monozygotic twins, one may consider the influence of genetic and/or environmental factors in their etiology. Hereditary relationships associated with oligodontia could help the clinicians to predict the possibility of its occurrence in other family members and in the next generations. However, clinicians should consider oligodontia when it is not hereditary. © 2013 Dental Investigations Society.Öğe Physical properties of different orthodontic cements(Urban & Vogel, 2015) Aksakallı, Sertaç; Malkoç, Meral Arslan; Çörekçi, Bayram; Malkoç, Sıddık; Toy, EbubekirIntroduction. We evaluated the water absorption, solubility, and compressive strength of different cements and resin-modified glass ionomer cements (RMGICs), namely AdhesorA (R), Ketac (TM) Cem, Ortho Band Paste LC (TM), Glass Ionomer Band Cement, and Transbond (TM) Plus. Our aims were to compare the mechanical and physical properties of the cements widely used in orthodontics and to define the most suitable cements in an oral environment in terms of those characteristics. Materials and methods. To assess compressive strength, the cements were subjected to compression tests done on a universal testing machine. To test water absorption and solubility, the weight changes in cement specimens were determined after immersion in distilled water for 1, 7, and 30 days. Results. Adhesor (R) and Ketac (TM) Cem presented significantly higher solubility values than other cements after water immersion for 1, 7, and 30 days (p < 0.001). Conclusion. Our results revealed that the traditional orthodontic cements have higher water solubility and water absorption values as well as lower compressive strength values than the RMGICs used in this study. Furthermore, Transbond (TM) Plus revealed the highest compressive strength, whereas AdhesorA (R) showed the lowest.Öğe Polymerization capacity of orthodontic composites analyzed by Fourier transform infrared spectroscopy(Mosby-Elsevier, 2011) Çörekçi, Bayram; Malkoç, Sıddık; Öztürk, Bora; Gündüz, Beniz; Toy, EbubekirIntroduction: The aim of this in-vitro study was to analyze the polymerization capacity of 5 orthodontic composites by determining the degree of monomer conversion (DC). Methods: Fourier transform infrared spectroscopy was used to evaluate the DC of the orthodontic composites immediately after polymerization and after storage in artificial saliva at 37 degrees C +/- 1 degrees C for 30 days. The resin-based adhesive composites investigated were Bisco Ortho (Bisco, Schaumburg, III), Heliosit Orthodontics (Ivoclar, Schaan, Liechtenstein), Kurasper F (Kuraray, Okayama, Japan), Light Bond (Reliance Orthodontic Products, Itasca, III), and Transbond XT (3M Unitek, Monrovia, Calif), cured with Elipar FreeLight 2 (3M ESPE, St Paul, Minn) for the testing of the DC values. Fifty cylindrical specimens were manufactured in molds. The data were analyzed by 2-factor analysis of variance (ANOVA) and Tukey HSD test. Results: According to 2-way ANOVA, the DC was significantly influenced by composite type (P < 0.05); after 30 days, there were no differences among the composite types for the DC. The interaction of orthodontic composites and time played a statistically significant role in the DC (P < 0.05), but there was no statistically significant influence of time for the DC (P > 0.05). Conclusions: The DC was found to change according to composite materials used, and Bisco Ortho showed the most DC performance. The DC of orthodontic composites is a complex process that is affected not only by inorganic filler content of the composite but also the monomer type and many other factors. Sufficient DC values of 5 commercially available orthodontic composites can be achieved with a new-generation light-emitting diode curing light. (Am J Orthod Dentofacial Orthop 2011;139:e299-e304)Öğe Real-time cell analysis of the cytotoxicity of orthodontic brackets on gingival fibroblasts(Sage Publications Ltd, 2014) Toy, Ebubekir; Malkoç, Sıddık; Çörekçi, Bayram; Bozkurt, Buket Şerife; Hakkı, Sema S.Purpose: The aim of this study was to evaluate the cytotoxic effects of 6 different orthodontic bracket types on human gingival fibroblasts (HGFs) using the xCELLigence system. Methods: The orthodontic brackets used in this study were gold-plated steel (Apollo Gold), titanium (Rematitan), stainless steel (Equilibrium 2), lucid ice (Inspire ICE), metal-reinforced ceramic (Clarity) and composite (OrthoFlex). Gingival fibroblasts were isolated from human gingival connective tissue of systemically healthy individuals. Tested brackets were incubated in DMEM culture medium for 72 hours according to ISO 10993-5 standards. Gingival fibroblasts were maintained with Dulbecco modified Eagle medium containing 10% fetal bovine serum. The xCELLigence system was used to evaluate cell survival. The statistical analysis used was ANOVA and Tukey-Kramer multiple comparison tests. Results: When the data were evaluated in the 30th hour, Apollo Gold showed significant decreases in cell index (P<0.001). It also showed statistically significant decreases (P<0.001) in the 65th hour, but Clarity and Inspire ICE showed significant increases in cell indices (P<0.001, P<0.01). In the 114th hour, Clarity and Equilibrium 2 showed statistically significant increases in cell indices (P<0.001). Inspire ICE and Rematitan demonstrated significant increases (P<0.05). There were significant decreases in cell index of Apollo Gold (P<0.001). Conclusions: The tested brackets are suitable for clinical application, but further studies using different test methods are needed for gold-plated brackets.Öğe Real-time cell analysis of the cytotoxicity of orthodontic mini-implants on human gingival fibroblasts and mouse osteoblasts(Mosby-Elsevier, 2012) Malkoç, Sıddık; Öztürk, Fırat; Çörekçi, Bayram; Bozkurt, Buket S.; Hakkı, Sema S.Introduction: The aim of this study was to evaluate the cytotoxic effects of orthodontic mini-implants on gingival fibroblasts and osteoblasts. Methods: The orthodontic mini-implants used in this study were Orthodontic Mini Implant (Leone, Florence, Italy), MTN (MTN, Istanbul, Turkey), AbsoAnchor (Dentos, Daegu, South Korea), IMTEC Ortho (3M Unitek, IMTEC, Ardmore, Okla), VectorTAS (Ormco, Glendora, Calif). The materials were incubated in Dulbecco's modified eagle's culture medium for 72 hours according to ISO 10993-5 standards (surface area-to-volume ratio of the specimen to cell-culture medium, 3 cm(2)/mL). A real-time cell analyzer (xCELLigence, Roche Applied Science, Mannheim, Germany; ACEA Biosciences, San Diego, Calif) was used to evaluate cell survival. After seeding 200 mu L of the cell suspensions into the wells of the E-plate 96, gingival fibroblasts were treated with bioactive components released by the metallic materials and monitored every 15 minutes for 190 hours. For the proliferation experiments, the statistical analyses used were 1-way analysis of variance and Tukey-Kramer multiple comparisons tests. Results: There was no significant differences between the human gingival fibroblast cell indexes of the control and study groups (P>0.05). When evaluated at 27 and 96 hours, only the VectorTAS mini-implants showed statistically significant decreases in the M3T3 cell index (P < 0.001) compared with the control group. No significant differences were found among the control and all study groups (P>0.05). Furthermore, the Leone and MTN mini-implants showed statistically significant decreases (P < 0.001) at 190 hours. Also, the VectorTAS mini-implants demonstrated a significant decline (P < 0.05) at the same time in the M3T3 cell index. Conclusions: These findings provide fundamental knowledge and new insights for future design and development of new biocompatible titanium alloys for orthodontic mini-implants and temporary anchorage devices. (Am J Orthod Dentofacial Orthop 2012;141:419-26)
