Biomedical subjects

Serdar Usumez

Publications and source records attributed to Serdar Usumez.

At least 19 recordsLinked to original sources

PubMed2006

Relationship between static natural head position and head position measured during walking.

INTRODUCTION: 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.

Adult↗

PubMed2006

New generation open-bite treatment with zygomatic anchorage.

This technical note aims to present the fabrication and application of a new generation of posterior intrusion appliances using zygomatic anchorage. The use of zygomatic anchorage enables en masse impaction of the posterior segment without any side effects such as labial flaring. A 14-year-old, female Class II patient with an anterior open bite was treated with a new generation posterior intrusion appliance. At the end of treatment, a Class I canine and molar relationship and a correction of the anterior open bite were achieved. The molars were impacted 3.6 mm, and this impaction was maintained throughout the treatment. The mandibular plane showed a counterclockwise autorotation of 4 degrees. This case report demonstrates that zygomatic anchorage can be used effectively for molar intrusion and anchorage maintenance. However, further clinical studies with larger samples are required to confirm its effectiveness.

Adolescent↗

PubMed2005

Effect of cervical headgear wear on dynamic measurement of head position.

The aim of this study was to identify the effect of cervical headgear (CHG) wear on dynamic measurement of head posture during walking. Six male and 10 female patients (mean age, 11.9 +/- 1.9 years) who were receiving CHG therapy for correction of a Class II molar relationship as part of their orthodontic treatment were included in this study. Dynamic head posture measurements were recorded using an inclinometer and data logger apparatus during a walking session of 5 minutes. This procedure was repeated before (T1) and after (T2) insertion of CHG. The T1 and T2 measurements were repeated twice at 30-minute intervals. The mean dynamic head posture was calculated for each subject using the collected data. The means of these measurements were statistically compared using a paired t-test. Of the 16 subjects, 14 showed a cranial flexion with CHG wear in relation to T1 (1.4 to 8.9 degrees). The other two subjects showed a cranial extension of -1.6 and -3.8 degrees. The mean values at T1, T2 and T1-T2 were 1.4, -1.8, and 3.1 degrees, respectively, which indicated a mean cranial flexion at T2 in relation to T1. According to the paired sample t-test, there were statistically significant differences between the two measurements of dynamic head posture recorded before and after CHG insertion (P < 0.001). CHG wear causes a significant cranial flexion which may be responsible for its effects on the mandible.

Cervical Vertebrae↗

PubMed2005

Pulpal temperature rise during light-activated bleaching.

The 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 alpha 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 (11.7 degrees C). The light-emitting diode unit produced the lowest temperature changes (6.0 degrees C); 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.

Dental Pulp↗

PubMed2005

Reproducibility of airway dimensions and tongue and hyoid positions on lateral cephalograms.

INTRODUCTION: 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.

Adolescent↗

PubMed2005

Thermal changes in the pulp chamber during different adhesive clean-up procedures.

The 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 deltaT 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 low-speed 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.

Analysis of Variance↗

PubMed2005

Dental and alveolar arch widths in normal occlusion and Class III malocclusion.

The 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 t-test 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 Ill 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.

Adult↗

PubMed2005

Dental and alveolar arch widths in normal occlusion, class II division 1 and class II division 2.

The 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 malocclusions 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.

Adolescent↗

PubMed2005

The effect of head rotation on cephalometric radiographs.

The aim of this study was to identify the potential projection errors of lateral, postero-anterior (PA) and submentovertex (SMV) cephalometric radiographs due to head rotation in the vertical z-axis. For this investigation, a complete human dry skull of an adult was used. The skull was rotated from 0 to +/-14 degrees at 2 degree intervals. A vertical axis, the z-axis, was used as the rotational axis to expose 15 lateral and 15 PA cephalometric radiographs. The skull was tilted on each side, again at 2 degree intervals, to expose the 15 SMV films. A series of linear and angular measurements was carried out on all cephalograms. The results revealed that horizontal linear and angular measurements between the horizontal planes on lateral cephalograms were subject to changes from 16.1 to 44.7 per cent with a 14 degree rotation of the head position. For PA cephalograms, again horizontal linear measurements, particularly mandibular length, were subject to a projection error of up to 34.9 per cent with head rotation. On the other hand, projection errors were within the 3-4 per cent limit for SMV radiography. The findings indicate that: (1) linear measurements and the measurement of angles between the horizontal planes are likely to be affected by head rotation in lateral cephalograms, (2) angular measurements demonstrate smaller variations with changing rotation of the head in PA cephalograms, (3) SMV radiographs are less vulnerable to head rotation. Vertical linear measurements of lateral cephalograms and angular measurements of PA radiographs are more reliable in minimizing the projection errors associated with head rotation.

Adult↗

PubMed2004

The effects of early preorthodontic trainer treatment on Class II, division 1 patients.

The 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.

Cephalometry↗

PubMed2003

Effect of complete dentures on dynamic measurement of changing head position: A pilot study.

STATEMENT OF PROBLEM: Complete dentures contribute significantly to the facial esthetics of edentulous patients. However, information as to the effect of complete dentures on the natural position of the head is limited. PURPOSE: The purpose of this pilot study was to evaluate the immediate and 30-day effect of wearing complete dentures on the dynamic natural head position measured during walking. MATERIALS AND METHODS: The sample consisted of a volunteer group of 16 patients, 8 women and 8 men, who received new complete dentures. The ages of the subjects ranged from 45 to 64 years (mean=52 years). Dynamic measurement of head posture was carried out by a specially constructed inclinometer device. Each subject in turn was fitted with the inclinometer system and instructed to walk in a relaxed manner for 5 minutes. The data, measured as degrees, were stored in a pocket data logger. This procedure was repeated before insertion of dentures (T1), immediately after insertion of dentures (T2), and 30 days after insertion of dentures (T3). Stored dynamic head posture data were transferred to computer for analysis. The means of the measurements were statistically compared with Friedman and following Wilcoxon tests (alpha =.05). RESULTS: Twelve of 16 (75%) subjects showed an average of 4.6 degrees of cranial extension immediately after insertion of dentures. Six (37.5%) subjects showed an average of 6.4 degrees of cranial flexion, and 8 (50%) subjects showed an average of 5.2 degrees of cranial extension at T3 relative to the T1 measurement. Dynamic head posture measurements of the other 2 subjects remained unchanged. There were significant differences between different measurements of dynamic head posture positions (P<.025). However, only the T1 and T2 measurements were significantly different (P<.015). CONCLUSION: The findings indicate that the statistically significant average extension 4.6 degrees in subjects immediately after insertion of complete dentures was not stable after a 30-day evaluation period and did not produce any statistically significant change. The overall effect of wearing dentures was an irregular flexion or extension pattern on dynamic head posture.

Dental Occlusion, Balanced↗

PubMed2003

Effects of extraction and nonextraction treatment on class I and class II subjects.

This study aims to examine the profile as well as the dentoalveolar and skeletal effects of extraction or nonextraction treatment in a wide range of patients including Class I and Class II, division 1 cases. Results achieved with extraction and nonextraction modalities have also been compared. The study was performed on pretreatment and posttreatment lateral cephalograms of 87 orthodontic patients. There were no significant differences between the pretreatment values of extraction and nonextraction Class I groups, whereas SN-GoGn (degrees), maxillary incisor to A-Po (degrees), mandibular incisor to A-Po (mm), Co-Gn (mm), overjet (mm), and overbite (mm) measurements of extraction Class II group were significantly higher before the treatment. After treatment, these differences were eliminated in the Class II group; however, incisors were significantly protruded in both nonextraction groups. No other differences in profile or lip position were found between the extraction and nonextraction groups. The results of this study indicate that in successfully treated cases, whether by extraction or nonextraction, the same soft and hard tissue profile posttreatment end points were reached except for the incisor positioning, which is rather easier to anticipate than profile and soft tissue changes. The simple statement that extraction means a more retrusive or dished-in profile seems to be unacceptable. It seems that a more thorough assessment and investigation including pretreatment extent of crowding and factors related to anchorage, soft tissue thickness, and strain should be carried out.

Adolescent↗

PubMed2003

Effect of self-etching primers on bond strength--are they reliable?

Currently introduced self-etching primers combine conditioning and priming agents into a single product. The purpose of this study was to determine the effects of using three self-etching primers on the shear bond strength (SBS) of orthodontic brackets and on the bracket/adhesive failure mode. Brackets were bonded to extracted human teeth according to one of four protocols. In the control group, teeth were etched with 37% phosphoric acid. In the experimental groups, the enamel was conditioned with three different self-etching primers, Clearfil SE Bond (CSE), Etch & Prime 3.0 (EP3), or Transbond Plus (TBP), as suggested by the manufacturer. The brackets were then bonded with Transbond XT in all groups. The present in vitro findings indicate that conditioning with TBP before bonding orthodontic brackets to the enamel surface resulted in a significantly (P < or = .001) higher SBS (mean, 16.0 +/- 4.5 MPa) than that found in CSE, EP3, and the control (acid-etched [AE]) groups. CSE produced bond strength values (mean 11.5 +/- 3.3 MPa) that are statistically comparable to those produced by acid etching (mean 13.1 +/- 3.1 MPa). The use of EP3 for enamel conditioning resulted in the lowest mean SBS value (mean 9.9 +/- 4.0 MPa). A comparison of the adhesive remnant index scores indicated that there was more residual adhesive remaining on the teeth that were treated with conventional acid etching than in the CSE and EP3 groups. In the TBP group, the failure sites were similar to those of the AE group but different from those of the CSE group.

Acid Etching, Dental↗

PubMed2003

Comparative evaluation of a new removable Jasper Jumper functional appliance vs an activator-headgear combination.

The aim of this study was to comparatively evaluate the effects of an activator-headgear (HG) 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.

Activator Appliances↗

PubMed2003

Effect of rapid maxillary expansion on nocturnal enuresis.

One of the effects of rapid maxillary expansion (RME) is a reduction in nighttime bed-wetting. The aim of this prospective study was to investigate the effects of RME on nocturnal enuresis (NE) in children who are liable to psychosocial stress conditions. Eight children (six boys and two girls) who had not responded to different conventional medical treatments were included in the study. The subjects were between eight and 11 years of age with a mean age of nine years five months, and were residents of a government orphanage. All the children wet the bed at least one time every night and previously had been subjected to unsuccessful conventional treatment modalities. Maxillary expansion was performed using a rigid acrylic RME device. Lateral and PA cephalometric films and dental casts were used in the assessment of the dentofacial and nasopharyngeal structures. Data were analyzed using a paired t-test. In seven of the eight children, remarkable improvement was observed in NE after three to six mm RME. At the end of eight months observation, the mean rate of improvement in bed-wetting in the seven successful subjects was 74.2% (57.6-87.5%). The findings also indicated significant changes in the nasomaxillary structures and nasopharyngeal airway dimensions with the use of RME. However, none of the subjects became completely dry, and the disorder is probably multicausal including psychological emotions and tensions. This study demonstrated that RME treatment could cause relief for the enuretic children. However, the long-term success rate is still questionable.

Cephalometry↗

PubMed2003

Rapid maxillary expansion. Is it better in the mixed or in the permanent dentition?

The 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 1 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.

Cephalometry↗

PubMed2003

Mandibular symphyseal distraction and its geometrical evaluation: report of a case.

In this report, the case of a patient who has been treated with a different use of a tooth-borne custom-made mandibular symphyseal distraction device is presented. The difference in the application is that the distal arm of the device was sectioned during the retention phase to allow the possible relapse of displaced condyles to their original positions while the labial segment expansion is being maintained. The effect of this procedure was also evaluated on a geometrical model using measurements from the patient's cast. We conclude that symphyseal distraction is an effective and fast method of correcting orthodontic anomalies. The effect of the procedure on the condyle was only 3 degrees of distolateral rotation as calculated using the geometrical model.

Adolescent↗

PubMedDate not supplied

Temperature rise during adhesive and resin composite polymerization with various light curing sources.

This 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 (5.16 degrees C) and HQTH (4.28 degrees C), respectively. Temperature rise values produced by QTH (1.27 degrees C - 2.83 degrees C for adhesive resin; 1.86 degrees C - 2.85 degrees C 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 (1.16 degrees C - 2.08 degrees C for adhesive resin; 1.13 degrees C - 2.59 degrees C 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 5.6 degrees C value for pulpal health.

Analysis of Variance↗