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Öğe Comparative evaluation of a new removable jasper jumper functional appliance vs an activator-headgear combination(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2003) Sari, Z; Goyenc, Y; Doruk, C; Usumez, SThe aim of this study was to comparatively evaluate the effects of an activator-headgear (FIG) combination to a Jasper Jumper (JJ) plus occipital HG, which was incorporated into removable upper and lower plates. The study group consisted of 60 subjects with mandibular deficiency and a vertical growth pattern. Of these, 20 were treated with JJ appliance-HG incorporated to removable upper and lower plates, 20 were treated with an activator-HG combination. Another 20 subjects who refused orthodontic treatment served as controls. Pre- and postreatment lateral cephalograms and hand-wrist films were gathered for all 60 subjects. Lateral cephalograms were manually traced before being transferred to RMO JOE software by a digitizer. Measurements that are not included in the software were measured manually. Thirty-five dental and skeletal parameters were used in the study. The collected data were subjected to statistical analysis using SPSS packet software. Wilcoxon paired t-test was used for intragroup comparisons. Differences between groups were evaluated by analysis of variance and Bonferroni tests. Results suggest that ANB angle was decreased significantly in both treatment groups compared with the controls. Increase in total facial height was greater in the activator group than in the JJ group. Vertical growth inhibition of lower incisors was greater in the JJ group. The activator-HG appliance was more effective on the mandible, whereas the JJ appliance was mainly active on the maxilla. Thus, ideal cases for JJ-splinted appliance should be high-angle cases, particularly with maxillary excess and some mandibular deficiency.Öğe Comparison of clinical and magnetic resonance imaging diagnoses in patients with TMD history(BLACKWELL PUBLISHING LTD, 2004) Usumez, S; Oz, F; Guray, EThe aim of this study was to evaluate the diagnostic accuracy of a well-defined clinical examination for diagnosing anterior disc displacement with and without reduction. A series of 40 patients with temporomandibular disorder (TMD) history were examined according to well-defined routine criteria. This examination included detailed history-taking, standardized clinical head and neck examination that included measurements of the range of motion, palpation of the temporomandibular joints and muscles of mastication for pain and auscultation of joint sounds. Magnetic resonance images of the joints were used as 'gold standard'. Diagnostic accuracy of the clinical examination was 83% for determining normal disc-condyle relationship, 72% for diagnosing anterior disc displacement with reduction, and 81% for diagnosing anterior disc displacement without reduction. Our results suggest that anterior displacement of the disc can be diagnosed with considerable accuracy using a well-defined clinical examination only. Therefore, we conclude that not all patients with TMD symptoms require magnetic resonance imaging examination before treatment.Öğe Degree of conversion and surface hardness of resin cement cured with different curing units(QUINTESSENCE PUBLISHING CO INC, 2005) Ozturk, N; Usumez, A; Usumez, S; Ozturk, BObjective: The aim of this study was to evaluate the degree of conversion and Vickers surface hardness of resin cement under a simulated ceramic restoration with 3 different curing units: a conventional halogen unit, a high-intensity halogen unit, and a light-emitting diode system. Methods and Materials: A conventional halogen curing unit (Hilux 550) (40 S), a high-intensity halogen curing unit used in conventional and ramp mode (Optilux 501) (10 s and 20 s, respectively), and a light-emitting diode system (Elipar FreeLight) (20 s, 40 s) were used in this study. The dual-curing resin cement (Variolink 11) was cured under a simulated ceramic restoration (diameter 5 mm, height 2 mm), and the degree of conversion and Vickers surface hardness were measured. For degree of conversion measurement, 10 specimens were prepared for each group. The absorbance peaks were recorded using the diffuse-reflection mode of Fourier transformation infrared spectroscopy. For Vickers surface hardness measurement, 10 specimens were prepared for each group. A load of 200 N was applied for 15 seconds, and 3 evaluations of each of the samples were performed. Results: Degree of conversion achieved with Optilux 501 (20 s) was significantly higher than those of Hilux, Optilux 501 (10 s), Elipar FreeLight (20 s), and Elipar FreeLight (40 s). For Vickers surface hardness measurement, Optilux 501 (20 s) produced the highest surface hardness value. No significant differences were found among the Hilux, Optilux 501 (10 s), Elipar FreeLight (20 s), and Elipar FreeLight (40 s). Conclusion: The high-intensity halogen curing unit used in ramp mode (20 s) produced harder resin cement surfaces than did the conventional halogen curing unit, high-intensity halogen curing unit used in conventional mode (10 s) and light-emitting diode system (20 s, 40 s), when cured through a simulated ceramic restoration.Öğe Degree of conversion of two lingual retainer adhesives cured with different light sources(OXFORD UNIV PRESS, 2005) Usumez, S; Buyukyilmaz, T; Karaman, AI; Gunduz, BThe aim of this study was to evaluate the degree of conversion (DC) of two lingual retainer adhesives, Transbond Lingual Retainer (TLR) and Light Cure Retainer (LCR), cured with a fast halogen light, a plasma arc light and a light-emitting diode (LED) at various curing times. A conventional halogen light served as the control. One hundred adhesive samples (five per group) were cured for 5, 10 or 15 seconds with an Optilux 501 (fast halogen light), for 3, 6 or 9 seconds with a Power Pac (plasma arc light), or for 10, 20 or 40 seconds with an Elipar Freelight (LED). Samples cured for 40 seconds with the conventional halogen lamp were used as the controls. Absorbance peaks were recorded using Fourier transform infrared (FT-IR) spectroscopy. DC values were calculated. Data were analysed using Kruskal-Wallis and Mann-Whitney U-tests. For the TLR, the highest DC values were achieved in 6 and 9 seconds with the plasma arc light. Curing with the fast halogen light for 15 seconds and with the LED for 40 seconds produced statistically similar DC values, but these were lower than those with the plasma arc light. All of these light exposures yielded a statistically significantly higher DC than 40 seconds of conventional halogen light curing. The highest DC value for the LCR was achieved in 15 seconds with the fast halogen light, then the plasma arc light curing for 6 seconds. These two combinations produced a statistically significantly higher DC when compared with the 40 seconds of conventional halogen light curing. The lowest DC for the LCR was achieved with 10 seconds of LED curing. The overall DC of the LCR was significantly higher than that of the TLR. The results suggest that a similar or higher DC than the control values could be achieved in 6-9 seconds by plasma arc curing, in 10-15 seconds by fast halogen curing or in 20 seconds by LED curing.Öğe Dental and alveolar arch widths in normal occlusion and class III malocclusion(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2005) Uysal, T; Usumez, S; Memili, B; Sari, ZThe aim of this study was to compare the transverse dimensions of the dental arches and alveolar widths of Class III malocclusion group with a group of untreated normal occlusion subjects. This study was performed using measurements on dental casts of 150 normal occlusion (mean age, 21.6 +/- 2.6 years) and 100 Class III malocclusion (mean age, 15.4 +/- 2.2 years) subjects. Independent samples Mest was applied for comparing the groups. The findings of this study indicated that the mandibular intercanine and intermolar alveolar widths were significantly larger in the Class III group when compared with the normal occlusion sample (P < .001). Maxillary interpremolar, intermolar widths and all maxillary alveolar width measurements were significantly narrower in the Class III group (P < .001). In addition, the lower canine and premolar alveolar width measurements were also statistically significantly larger in the normal occlusion group when compared with the Class III malocclusion group (P < .001). Subjects with Class III malocclusion tend to have the maxillary teeth inclined to the lingual and mandibular teeth inclined to the buccal direction because of the restriction of maxillary growth and development according to dental arch width measurements. Therefore, rapid maxillary expansion should be considered before or during the treatment of a Class III patient with or without face-mask therapy.Öğe Dental and alveolar arch widths in normal occlusion, class II division 1 and class II division 2(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2005) Uysal, T; Memili, B; Usumez, S; Sari, ZThe aim of this study was to compare the transverse dimensions of the dental arches and alveolar arches in the canine, premolar, and molar regions of Class II division 1 and Class II division 2 malocclusion groups with normal occlusion subjects. This study was performed using measurements on dental casts of 150 normal occlusion (mean age: 21.6 +/- 2.6 years), 106 Class II division 1 (mean age: 17.2 +/- 2.4 years), and 108 Class II division 2 (mean age: 18.5 +/- 2.9 years) malocclusion subjects. Independent-samples t-test was applied for comparisons of the groups. These findings indicate that the maxillary interpremolar width, maxillary canine, premolar and molar alveolar widths, and mandibular premolar and molar alveolar widths were significantly narrower in subjects with Class II division 1 malocclusion than in the normal occlusion sample. The maxillary interpremolar width, canine and premolar alveolar widths, and all mandibular alveolar widths were significantly narrower in the Class II division 2 group than in the normal occlusion sample. The mandibular intercanine and interpremolar widths were narrower and the maxillary intermolar width measurement was larger in the Class II division 2 subjects when compared with the Class II division 1 subjects. Maxillary molar teeth in subjects with Class II division 1 maloc-clusions tend to incline to the buccal to compensate the insufficient alveolar base. For that reason, rapid maxillary expansion rather than slow expansion may be considered before or during the treatment of Class II division 1 patients.Öğe The effect of head rotation on cephalometric radiographs(OXFORD UNIV PRESS, 2005) Malkoc, S; Sari, Z; Usumez, S; Koyuturk, AE[Abstract not Available]Öğe Effect of light-emitting diode on bond strength of orthodontic brackets(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2004) Usumez, S; Buyukyilmaz, T; Karaman, AIThe aim of this study was to evaluate the effect of light-emitting diode (LED) light curing on shear bond strength (SBS) of orthodontic brackets bonded to teeth. Light exposure of 40 seconds from a conventional halogen-based light-curing unit was used as a control. Eighty human premolars were divided into four groups of 20 each. Brackets were bonded to acid-etched teeth with Transbond XT light-cured adhesive. In the first group, the adhesive was light cured for 40 seconds with a conventional halogen unit (XL3000, 3M). In the other three groups, adhesive was cured with a commercial LED unit (Elipar FreeLight, 3M ESPE) for 10, 20, or 40 seconds. SBS of brackets was measured on a universal testing machine and recorded in megapascals. Adhesive remnant index (ARI) scores were determined after failure of brackets. Data were analyzed using analysis of variance and chi-square tests. No statistically significant differences were found among the SBS values of halogen-based light-cured (13.1 +/- 3.1 MPa) and 20- and 40-second LED-cured (13.9 +/- 4.8 MPa and 12.7 +/- 5.1 MPa) specimens (P > .05). However, 10 seconds of LED curing yielded significantly lower SBS (P < .05). No statistically significant differences were found between the ARI scores among groups. The results of this study are promising for the orthodontic application of LED-curing units, but further compatibility and physical characteristic studies of various orthodontic adhesives and clinical trials should be performed before validation.Öğe The effects of early preorthodontic trainer treatment on class II, division 1 patients(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2004) Usumez, S; Uysal, T; Sari, Z; Basciftci, FA; Karaman, AI; Guray, EThe aim of this study was to clarify the dentoskeletal treatment effects induced by a preorthodontic trainer appliance treatment on Class II, division 1 cases. Twenty patients (10 girls and 10 boys, mean age 9.6 +/- 1.3 years) with a Class II, division 1 malocclusion were treated with preorthodontic trainer appliances (Myofunctional Research Co., Queensland, Australia). The patients were instructed to use the trainer every day for one hour and overnight while they slept. A control group of 20 patients (mean age 10.2 +/- 0.8 years) with untreated Class II, division 1 malocclusions was used to eliminate possible growth effects. Lateral cephalograms were taken at the start and end of treatment. Final cephalograms were taken 13.1 +/- 1.8 months after trainer application, compared with a mean of 11.2 +/- 2.4 months later for the control group. The mean and standard deviations for cephalometric measurements were analyzed by paired-samples t-test and independent-samples t-tests. At the end of the study period, the trainer group subjects showed significant changes including anterior rotation and sagittal growth of the mandible, increased SNB and facial height, reduced ANB, increased lower incisor proclination, retroclination of upper incisors, and overjet reduction. However, only total facial height increase, lower incisor proclination, and overjet reduction were significantly higher when compared with the changes observed in the control group. This study demonstrates that the preorthodontic trainer application induces basically dentoalveolar changes that result in significant reduction of overjet and can be used with appropriate patient selection.Öğe The efficiency of different light sources to polymerize resin cement beneath porcelain laminate veneers(WILEY, 2004) Usumez, A; Ozturk, AN; Usumez, S; Ozturk, BPlasma arc light units for curing resin composites have been introduced with the claim of relatively short curing times. The purpose of this study was to evaluate the efficiency of two different light sources to polymerize dual curing resin cement beneath porcelain laminate veneers. Twenty extracted healthy human maxillary centrals were used. Teeth were sectioned 2 mm below the cemento-enamel junction and crown parts were embedded into self-cure acrylic resin, labial surface facing up. Cavity preparation was carried out on labial surfaces. These teeth were divided into two groups of 10 each. The resin cement/veneer combination was exposed to two different photo polymerization units. A conventional halogen light (Hilux 350, Express Dental Products) and a plasma arc light (Power PAC, ADT) were used to polymerize resin cement. Ten specimens were polymerized conventionally (40 s) and the other specimens by plasma arc curing (PAC) (6 s). Two samples from each tooth measuring 1.2 x 1.2 x 5 mm were prepared. These sections were subjected to microshear testing and failure values were recorded. Statistically significant differences were found between the bond strength of veneers exposed to conventional light and PAC unit (P < 0.001). Samples polymerized with halogen light showed better bond strength. The results of this study suggest that the curing efficiency of PAC through ceramic was lower compared with conventional polymerization for the exposure durations tested in this study.Öğe Influence of different light sources on microleakage of class V composite resin restorations(WILEY, 2004) Ozturk, AN; Usumez, A; Ozturk, B; Usumez, SThe aim of this study was to evaluate the effect of three different curing units on microleakage of class V composite restorations. Class V cavities were prepared on the buccal surfaces of 45 extracted premolar teeth. The teeth were randomly divided into three groups of 15 each. A conventional halogen curing unit (Hilux 350), a high intensity halogen curing unit (Optilux 501) and plasma arc curing unit (Power Pac) were used to polymerize composite resin (Vitalesence). After restoration, the teeth were thermocycled for 100 cycles between 5 degrees and 55 degreesC using a dwell time of 30 s and exposed to a dye. Results showed that there was no significant difference among three different curing units (P > 0.05), however the microleakage at the dentin margins was greater than the enamel margins (P < 0.05). Clinical relevance: Plasma arc curing or fast halogen units cure composite materials at a faster rate than conventional curing units because of the high light intensity. High intensity halogen curing units and plasma arc curing units might be useful alternatives in composite polymerization. Therefore, these units are suggested for clinical use to save chair side time.Öğe Pulpal temperature rise during light-activated bleaching(WILEY, 2005) Eldeniz, AU; Usumez, A; Usumez, S; Ozturk, NThe purpose of this study was to measure intrapulpal temperature rise induced by two kinds of bleaching gels when the tooth was exposed to a variety of light-curing units and a diode laser in vitro. The root portions of 80 extracted intact human maxillary central incisors were sectioned with a carborundum disk approximately 2 mm below the cementoenamel junction perpendicular to the long axis of the teeth. Two bleaching agents containing heat-enhancing colorant was applied to the labial surface. Light-curing units used were a conventional halogen (40 s), a high-intensity halogen (30 s), a light-emitting diode unit (40 s), and a diode laser (15 s). The temperature rise was measured in the pulpal chamber with a J-type thermocouple wire that was connected to a data logger. Ten specimens were used for each system and bleaching-agent combination. Differences between the starting temperature and highest temperature reading were taken and the calculated temperature changes were averaged to determine the mean value in temperature rise. Temperature rise values were compared using two-way analysis of variance (ANOVA) at a preset a of 0.05. Temperature rise varied significantly depending on curing unit and diode laser used. The diode laser induced significantly higher temperature increases than any other curing unit (11.7degreesC). The light-emitting diode unit produced the lowest temperature changes (6.0degreesC); however, there were no statistically significant differences among the curing units and there were no statistically significant differences between bleaching agents. Light activation of bleaching materials with diode laser caused higher temperature changes as compared to other curing units and the temperature rise detected was viewed as critical for pulpal health. (C) 2004 Wiley Periodicals, Inc.Öğe Rapid maxillary expansion. Is permanent it better in the mixed or in the dentition?(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2003) Sari, Z; Uysal, T; Usumez, S; Basciftci, FAThe aim of this study was to compare the dentoskeletal effects of a modified acrylic-bonded rapid maxillary expansion (RME) device when it is used in the mixed and permanent dentitions. The study group consisted of 51 patients in the mixed and permanent dentition (26 girls and 25 boys) who underwent RME treatment. Group I was composed of 34 subjects in the mixed dentition (19 girls and 15 boys; mean age, 9.2 +/- 1.3 years). Group 2 consisted of 17 subjects in the permanent dentition (seven girls and 10 boys; mean age 12.7 +/- 1.2 years). Lateral and frontal cephalograms and upper dental casts were collected before treatment (T1), after treatment (T2), and after retention (T3). Intragroup and intergroup changes were evaluated by paired t-test and Student's t-test, respectively. In both groups after RME, the maxilla moved forward; mandible rotated posteriorly; facial height increased; nasal, maxillary, and maxillary intercanine and first molar widths increased; and the upper molars tipped buccally. Almost all these significant changes were stable at follow-up (T3). When overall (T1 - T3) differences were considered, upper molars tipped more, and the ANB angle increased less in the mixed dentition group compared with the permanent dentition group (P < .01). Within the limits of this study, the results suggest that the orthopedic effects of RME are not as great as expected at early ages, and it might be a better alternative to delay RME to early permanent dentition.Öğe Relationship between static natural head position and head position measured during walking(MOSBY, INC, 2006) Usumez, S; Uysal, T; Orhan, M; Soganci, EIntroduction: The aim of this project was to determine whether there is a statistically significant difference between the means of static and dynamic (measured during walking) measurements of head posture. Methods: The sample consisted of 50 subjects, 25 women and 25 men, 20 to 25 years of age. None had a history of orthodontic treatment, head or neck injury, or nasal breathing problems, and none wore eyeglasses to correct vision. Static measurement of head position was recorded by using the self-balance position. Dynamic measurements of head position were, made with an inclinometer device with the subject walking in a relaxed manner for 5 minutes. The data, measured in degrees, were stored in a pocket data logger. Recorded static and dynamic head posture data were transferred to a computer for analysis. The means of the measurements were statistically compared with the t test (alpha = .05). The mean walking head position was tipped forward relative to the mean static head position. Results: The mean value of static position minus walking head position measurements was +4.60 degrees. The differences between the 2 recordings were statistically significant (P < .001). Conclusions: Static and walking head position measurements are not interchangeable. Therefore, it might be advisable to use the mean dynamic measurement of head position to represent natural head position for positioning when taking case records such as lateral and posteroanterior cephalograms, clinical extraoral photography, or 3-dimensional imaging.Öğe Reproducibility of airway dimensions and tongue and hyoid positions on lateral cephalograms(MOSBY-ELSEVIER, 2005) Malkoc, S; Usumez, S; Nur, M; Donaghy, CEIntroduction: The aim of this study was to evaluate the reproducibility of airway dimensions and tongue and hyoid positions on lateral cephalometric radiographs. Methods: Three lateral cephalograms each of 30 patients were obtained in natural head positions at 30-minute intervals. Twelve measurements, including pharyngeal airway dimensions and tongue and hyoid positions, were taken. The relationships between 3 sets of measurements were evaluated by using repeated analysis of variance, Dahlberg's method error formula, and correlation coefficient. Results: No statistically significant differences were found between the 3 sets of measurements with the repeated analysis of variance (P > .05). Correlation coefficient values ranged between 0.964 (vertical position of the hyoid) and 0.683 (hypopharyngeal airway width). The average method error was 1.22 mm. Conclusions: The results suggest that airway dimension and tongue- and hyoid-position measurements are highly reproducible on natural-head-position cephalograms.Öğe Reproducibility of natural head position measured with an inclinometer(MOSBY, INC, 2003) Usumez, S; Orhan, MSagittal (pitch) and transversal (roll) natural head position (NHP) was measured once in 20 subjects, 18 to 24 years of age, with an inclinometer; the measurements were repeated 2 years later. The method error (reproducibility) after 2 years was 1.1degrees for sagittal and transversal measurements. The mean change in NHP measurement was -0.3degrees for both measurements, and the variance was 1.21degrees (= 1.1(2)).Öğe Temperature rise during adhesive and resin composite polymerization with various light curing sources(OPERATIVE DENTISTRY INC, 2004) Ozturk, B; Ozturk, AN; Usumez, A; Usumez, S; Ozer, FThis study evaluated the temperature rise in two different adhesive (Clearfil SE Bond [CSEB] and EBS-Multi [EBSM]) and composite systems (Clearfil AP-X [CAPX,] Pertac II [PII]) by the same manufacturer when illuminated by four different light sources: Light-emitting diode (LED), Plasma arc curing (PAC), high intensity quartz tungsten halogen (HQTH) and quartz tungsten halogen (QTH). Forty dentin disks were prepared from extracted premolars. These dentin disks were placed in apparatus developed to measure temperature rise. Temperature rise during photopolymerization of adhesive resin and resin composite was then measured. The mean values of temperature increases for adhesive and resin composites did not differ significantly (p = 0.769). The highest temperature rise was observed during photopolymerization of EBSM with PAC (5.16degreesC) and HQTH (4.28degreesC), respectively. Temperature rise values produced by QTH (1.27degreesC - 2.83degreesC for adhesive resin; 1.86degreesC - 2.85degreesC for resin composite) for both adhesive and resin composites were significantly lower than those induced by PAC and HQTH (p < 0.05). However, these values were significantly higher than those produced by LED (1.16degreesC - 2.08degreesC for adhesive resin; 1.13degreesC - 2.59degreesC for resin composite). Light sources with high energy output (PAC and HQTH) caused significantly higher temperature rise than sources with low energy output (QTH and LED). However, in this study, no temperature rises beneath 1-mm dentin disk exceed the critical 5.6degreesC value for pulpal health.Öğe Thermal changes in the pulp chamber during different adhesive clean-up procedures(E H ANGLE EDUCATION RESEARCH FOUNDATION, INC, 2005) Uysal, T; Eldeniz, AU; Usumez, S; Usumez, AThe aim of this in vitro study was to measure the temperature changes in the pulpal chamber when different adhesive clean-up procedures were used. Ninety intact extracted human maxillary central incisors were used in the study. The teeth were divided into six groups of 15 teeth each. The removal of the remaining composite on the tooth surface was performed with a tungsten carbide bur. The residual adhesive was removed using a high-speed handpiece with and without water cooling and a contra-angle handpiece with and without water cooling at high and low speeds. A J-type thermocouple wire was positioned in the center of the pulp chamber. The results were analyzed with analysis of variance (ANOVA) and the Tukey-honestly significant difference test. Two-factor ANOVA revealed significant interaction between the handpiece type and water cooling. In this study, the high-speed contra-angle handpiece without water cooling group had the highest Delta T values (7.58 degrees C +/- 1.84 degrees C) among all the clean-up procedures. The decrease in pulpal temperature with water cooling was -5.34 degrees C for the handpiece, -5.36 degrees C for the lowspeed contra-angle handpiece and -4.98 degrees C for the high-speed contra-angle handpiece. Clinicians should be aware of the potential thermal damage to the pulp, which may result from long clean-up procedures without water cooling. Adhesive removal procedures should be performed with adequate water cooling to prevent temperature increases that might be harmful to pulpal tissues.
