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Öğe Are the flowable composites suitable for orthodontic bracket bonding?(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2004) Uysal, T; Sari, Z; Demir, AThe study aims to determine the shear bond strength (SBS) values of different flowable composites (Pulpdent(R) Flows-Rite, 3M(TM) Filtek Flow, and Heraeus Kulzer(R) Flow Line) in comparison with a conventional orthodontic adhesive and the bond failure sites of these composites. Eighty extracted human premolars were divided into four groups of 20 teeth each. Brackets were bonded to the teeth in each test group with different composites,. according to the manufacturer's instructions. SBS values of these brackets were recorded (in MPa) using a universal testing machine. Adhesive remnant index (ARI) scores were determined after the failure of brackets. Data were analyzed using analysis of variance (ANOVA), Tukey honestly significant difference, and chi-square tests. SBS values of groups 1 (Transbond XT), 2 (Flows-Rite), 3 (Flow), and 4 (Flow Line) were found to be 17.10 +/- 2.48 MPa, 6.60 +/- 3.2 MPa, 7.75 +/- 2.9 MPa, and 8.53 +/- 3.50 MPa, respectively. The results of this study demonstrate that the orthodontic adhesive (Transbond XT) had higher SBS values than the flowable composites. Results of ANOVA revealed statistically significant differences among the groups (P < .05). The SBS values were significantly lower in all flowable composite groups than the orthodontic adhesive. ARI scores were significantly different between the orthodontic adhesive and all the flowable groups investigated. The use of flowable composites is not advocated for orthodontic bracket bonding because of significantly lower SBS values achieved.Öğe The association of occlusal factors with masticatory muscle tenderness in 10-to 19-year old Turkish subjects(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2005) Demir, A; Uysal, T; Basciftci, FA; Guray, EThe aims of this study were (1) to investigate the relationship between occlusal factors and masticatory muscle tenderness among 10- to 19-year-old (mean 14 years eight months) Turkish subjects and (2) to identify possible sex differences between them. The sample consisted of 716 individuals (355 male and 361 female subjects). Tenderness with palpation of masseter and temporalis muscles and functional manipulation of lateral and medial pterygoid muscles was registered. The examiners recorded the Angle classification bilaterally for molars, presence of anterior and posterior crossbites, excessive overjet, open and deep bites, functional shift, and severity of anterior crowding. Associations between the occlusal factors and muscle tenderness according to sex were evaluated with chi-square analysis. Statistically significant associations were found between masticatory muscle tenderness and all the investigated occlusal factors except posterior crossbite and functional shift. Masseter, medial, and lateral pterygoid muscle tenderness was higher in female subjects. Medial and lateral pterygoid muscle tenderness in Class I cases and masseter and medial pterygoid muscle tenderness in Class II, division 1 malocclusion cases were higher in female subjects (P <.05). In open-bite cases, medial pterygoid muscle tenderness (P <.05), in deep-bite cases, masseter (P <.01) and medial pterygoid (P <.05) muscle tenderness, and in excessive overjet cases, masseter muscle tenderness (P <.05) were also higher in female subjects. These results suggest that greater masticatory muscle tenderness in female subjects may contribute to the greater prevalence of temporomandibular disorders in them.Öğe The effect on shear bond strength of different antimicrobial agents after acid etching(OXFORD UNIV PRESS, 2005) Malkoc, S; Demir, A; Sengun, A; Ozer, FThe aim of the present study was to determine whether the application of different primers containing antibacterial agents (Micro Prime (TM), Seal&Protect (TM), and Gluma Desensitizer (TM)) can affect the shear bond strength (SBS) of an orthodontic resin composite. Seventy-two crowns of extracted lower human incisors were mounted in acrylic resin leaving the buccal surface of the crowns parallel to the base of the moulds. The teeth were randomly distributed into three experimental and one control group, each containing 18 teeth. In each experimental group, the primers were applied to the etched enamel surfaces. In the control group, no antibacterial primer was used. An orthodontic composite resin was applied to the surface into cylindrical-shaped plastic matrices after application of an orthodontic adhesive primer (Transbond XT). For shear bond testing, a stubby-shaped force transducer apparatus (Ultradent) was applied at a crosshead speed of 1 mm/minute to each specimen at the interface between the tooth and the composite until failure occurred. A Kruskal-Wallis one-way ANOVA and a Mann-Whitney U-test with a Bonferroni adjustment were used for statistical analysis. There was no significant difference between Seal&Protect (TM) (27.98 +/- 8.73 MPa) and the control (35.15 +/- 7.85 MPa) (P > 0.05). However, Gluma (TM) (21.61 +/- 7.96 MPa) and Micro Prime (TM) (14.89 +/- 5.55 MPa) caused a decrease in bond strength (P < 0.05). No statistically significant difference was observed between Seal&Protect (TM) and Gluma (TM) (P > 0.05). As triclosan containing Seal&Protect (TM) did not cause a significant decrease in bond strength, it can potentially be used under an orthodontic resin composite to obtain an antibacterial effect. However, further in vivo studies are required.Öğe Effects of camouflage treatment on dentofacial structures in Class II division 1 mandibular retrognathic patients(OXFORD UNIV PRESS, 2005) Demir, A; Uysal, T; Sari, Z; Basciftci, FAThe aims of this study were to determine the changes in the dentofacial structures of Class II division 1 mandibular retrognathic patients treated with bilateral extraction of the upper first premolars, and to compare pre- and post-treatment values with the cephalometric norms of Anatolian Turkish adults. The Class II division 1 subjects included 20 males and 33 females (mean age: 17.08 +/- 1.03 years). All received comprehensive orthodontic treatment using an edgewise appliance and appropriate headgear. Lateral cephalograms were taken at the beginning and end of treatment. Twenty-five (14 linear and 11 angular) measurements were analysed on each radiograph. Each cephalogram was traced and digitized. For statistical evaluation, paired and independent-samples t-tests were performed. When the pre- and post-treatment measurements were compared, statistically significant differences were found for nine of 25 measurements. During treatment the facial axis, U1-SN (degrees), U1-NA (mm), U1-NA (degrees), H angle and upper lip to E plane measurements decreased, while N-ANS, interincisal angle and upper lip to Steiner S line increased. No statistically significant gender differences were found. Significant improvements were determined in ANS-Me and L1-APo measurements compared with Turkish norms. However, statistically significant deterioration was found in values related to point A, upper incisor and lower lip measurements. The findings demonstrates that camouflage treatment in Class II, mandibular retrognathic subjects has characteristic skeletal, dental and soft tissue effects on the dentofacial complex.Öğe Effects of chlorhexidine and povidone-iodine mouth rinses on the bond strength of an orthodontic composite(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2005) Demir, A; Malkoc, S; Sengun, A; Koyuturk, AE; Sener, YThe purpose of this study was to determine whether the application of two antibacterial mouth rinses to etched and unetched enamel affects the shear bond strength (SBS) of an orthodontic composite resin. Eighty-five lower human incisors were divided into five groups, ie, group 1: control group, no mouth rinse was used; groups 2 and 3: mouth rinses were applied to the intact enamel surface before etching; groups 4 and 5: mouth rinses were applied to the etched enamel. A bonding agent and a composite resin were applied to the teeth surface. For shear bond testing, the specimens were mounted in a universal testing machine, and an apparatus attached to a compression load cell was applied to each specimen until failure occurred. The data were analyzed using analysis of variance and Tukey honestly significance tests. Fracture modes were analyzed by Mann-Whitney U-test. There was no statistically significant difference between the SBS values of group 1 (31.64 +/-- 3.62 MPa) and group 4-five experimental applications (P >= .05). However, the SBS value of group 3 (36.56 +/- 5.95 MPa) was significantly larger than those of group 4 (30.00 +/- 4.97 MPa) and group 5 (30.26 +/- 7.30 MPa). In addition, no significant differences were observed between group 1 and groups 2 (34.33 +/- 7.26 MPa) and 3 (36.56 +/- 5.95 MPa) (P >= .05). Because the application of chlorhexidine and povidone-iodine before acid etching did not cause any decrease in bond strength, it is advisable for use under the orthodontic resin composite to obtain an antibacterial effect or to prevent the risk of bacteremia.Öğe The influence of extraction treatment on holdaway soft-tissue measurements(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2004) Basciftci, FA; Uysal, T; Buyukerkmen, A; Demir, AThe aims of this study were (1) to determine the changes in the soft-tissue measurements of orthodontic patients treated with four first premolars extractions as determined by the Holdaway Analysis, (2) to investigate the sexual differences between pre- and posttreatment values, and (3) to compare the Holdaway soft-tissue norms with findings in Anatolian Turkish adults. Pretreatment and posttreatment lateral cephalograms of 58 patients (26 boys and 32 girls) were evaluated. During treatment, the H angle, soft tissue subnasale to H line, and upper-lip strain decreased, and the upper-lip thickness, inferior sulcus to H line, and nose prominence increased. No statistically significant sex differences were found between the pre- and posttreatment values of the four premolar extraction cases. When the pretreatment values were compared with the Holdaway soft-tissue norms of Anatolian Turkish adults, seven variables showed statistically significant differences. When the posttreatment values were compared, six measurements showed statistically significant differences. It was determined that some measurements (H angle, inferior sulcus to H line, upper-lip thickness) moved closer to the Anatolian Turkish norms with extraction of four first premolars. However, upper-lip strain measurement changed in an undesirable direction during the treatment. In this study, the sample began treatment with greater facial imbalance, and the facial esthetics improved during treatment. It is necessary to investigate this difference in future studies using larger sample sizes.Öğe The relationship between bruxism and occlusal factors among seven- to 19-year-old Turkish children(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2004) Demir, A; Uysal, T; Guray, E; Basciftci, FAThe aim of this study was (1) to investigate the relationship between occlusal factors and bruxism among 965 Turkish subjects (472 boys and 493 girls) with a mean age of 12.8 years (range, seven to 19 years); and (2) to identify possible sex differences between girls and boys. This sample was divided into two groups of bruxers or nonbruxers based on a clinical examination and self-reports. The examiner recorded the Angle molar classification bilaterally, severity of anterior crowding, existence of anterior and posterior crossbite, open and deep bite, functional shift, and excessive overjet. The relationships between occlusal factors and bruxism and sex differences between boys and girls were evaluated with chi-square analysis (chi(2)) using the SPSS software package. The results showed that bruxism was diagnosed in 12.6% of all subjects. The evaluation of the findings indicated that no statistically significant relationships were determined between bruxism and occlusal factors. No sex differences were found between occlusal factors in relation to bruxism. The prevalence of bruxism in boys and girls was similar, and no statistically significant differences were found. It is concluded that none of the occlusal factors seem to play a role in the development of bruxism. However, additional longitudinal studies with larger samples need to be conducted to determine if there is any relationship between occlusal factors and bruxism.
