Abdullah Demir

Angular photogrammetric analysis of the soft tissue facial profile of Turkish adults

One of the most important components of orthodontic diagnosis and treatment planning is the evaluation of the patients soft tissue profile. The aim of this study was to develop angular photogrammetric standards for Class I Anatolian Turkish males and females. A random sample of 100 Turkish individuals (46 males and 54 females; ages 19-25 years) was obtained. The photographic set-up consisted of a tripod that held a 35 mm camera and a primary flash. The camera was used in its manual position and photographic records were taken of the subjects in natural head posture. The photographic records, 35 mm slide format, were digitized and analyzed using the Quick Ceph Image software program for Windows. Twelve measurements were digitally analyzed on each photograph. For statistical evaluation a Students t-test was performed and the reliability of the method was analyzed. The results were compared with reported norms of facial aesthetics. The nasofrontal (G-N-Prn), nasal (Cm-Sn/N-Prn), vertical nasal (N-Prn/TV), and nasal dorsum (N-Mn-Prn) angles showed statistically insignificant gender differences (P>0.05). The nasolabial angle (Cm-Sn-Ls) demonstrated large variability. Gender differences were present in the mentolabial (Li-Sm-Pg) and cervicomental (G-Pg/C-Me) angles. The mentolabial angle showed a high method error and large variability. Facial (G-Sn-Pg) and total facial (G-Prn-Pg) convexity angles were similar, while Cm-Sn-Ls angle range was larger compared with other angles. The mean values obtained from this sample can be used for comparison with records of subjects with the same characteristics and following the same photogrammetric technique. Angular photogrammetric profile analysis can provide the orthodontist with a way of determining problems associated with various soft tissue segments of the face.

Are the Flowable Composites Suitable for Orthodontic Bracket Bonding

The study aims to determine the shear bond strength (SBS) values of different flowable composites (Pulpdent Flows-Rite, 3M Filtek Flow, and Heraeus Kulzer 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 manufacturers 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.

The Relationship Between Bruxism and Occlusal Factors Among Seven- to 19-Year-Old Turkish Children

The 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 (chi2) 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.

The Association of Occlusal Factors with Masticatory Muscle Tenderness in 10- to 19-Year Old Turkish Subjects

The 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.

Effects of Chlorhexidine and Povidone-Iodine Mouth Rinses on the Bond Strength of an Orthodontic Composite

The 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 > or = .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 > or = .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.

The Influence of Extraction Treatment on Holdaway Soft-Tissue Measurements

The 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.

Comparison of retention characteristics of Essix and Hawley retainers

Objective We aimed to compare the retention characteristics of Essix and Hawley retainers. Methods Adolescents undergoing fixed appliance treatment at 2 centers were recruited for this study. Twenty-two patients (16 women and 6 men) wore Essix retainers (Essix group) while 20 (14 women and 6 men) wore Hawley retainers (Hawley group). The mean retention time was 1 year, and the mean follow-up recall time for both groups was 2 years. Two qualified dental examiners evaluated the blind patient data. Maxillary and mandibular dental casts and lateral cephalograms were analyzed at 4 stages: pretreatment (T1), post-treatment (T2), post-retention (T3), and follow-up (T4). Results The results revealed that Essix appliances were more efficient in retaining the anterior teeth in the mandible during a 1-year retention period. The irregularity index increased in both arches in both groups after a 2-year post-retention period. The mandibular arch lengths increased during treatment and tended to return to their original value after retention in both groups; however, these changes were statistically significant only in the Hawley group. Cephalometric variables did not show any significant differences. Conclusions The retention characteristics of both Essix and Hawley retainers are similar.

Conventional and high intensity halogen light effects on water sorption and microhardness of orthodontic adhesives.

OBJECTIVE To test the null hypothesis that when the equivalent total light energy is irradiated to three orthodontic adhesive resins, there is no difference between the microhardness and water sorption values regardless of the curing light sources. MATERIALS AND METHODS Samples were divided into six groups according to the combination of three orthodontic adhesives (Kurasper F, Light-Bond, Transbond XT) and two light intensities (quartz tungsten halogen [QTH] and high intensity quartz tungsten halogen [HQTH]). One half of each of the 40 samples of three adhesive pastes was polymerized for 20 seconds by a QTH light source, and the other half was polymerized for 10 seconds by a HQTH light source. Water sorption was determined and Vickers hardness was established with three measurements per sample at the top, center, and bottom. Statistical analysis was performed using two-way analysis of variance (ANOVA) with multiple comparisons (Tukey-HSD). RESULTS Statistically significant differences were found among all adhesives for water sorption and hardness values cured with QTH and HQTH. The HQTH curing unit resulted in higher values than did the QTH. The highest water sorption values were observed for Kurasper F cured with HQTH and the lowest value was observed for Transbond XT cured with QTH. For microhardness Light-Bond cured with HQTH produced the highest values, and Transbond XT cured with QTH produced the lowest. CONCLUSIONS When the equivalent total light energy is irradiated to three orthodontic adhesive resins, there are significant differences between the microhardness and water sorption values cured with the QTH and HQTH light source. The null hypothesis is rejected.

Conventional and High-Intensity Halogen Light Effects on Polymerization Shrinkage of Orthodontic Adhesives

The objectives of this study were to compare the polymerization shrinkage of three orthodontic adhesives. In addition we wanted to determine the effectiveness of the high-intensity quartz tungsten halogen (HQTH) in curing orthodontic adhesives on polymerization shrinkage with that of the quartz tungsten halogen (QTH). A total of 120 glass ring molds were prepared using a low-speed saw. The internal surface of the glass rings were roughened and etched. Adhesive pastes were placed into the glass molds, which were sandwiched between two glass slides. Samples were divided into six groups according to the combination of three orthodontic adhesives (Kurasper F, Light Bond, and Transbond XT) and two light intensities. One half of each 40 samples of three adhesive pastes was polymerized for 20 seconds by a QTH (Hilux 350), and the other half was polymerized for 10 seconds by a HQTH (Optilux 501). The volumetric polymerization shrinkage for each system was measured through the specific density method modified by Puckett and Smith. Statistical analysis was performed using two-way analysis of variance for intergroup comparisons. The HQTH-curing unit resulted in a more polymerization shrinkage than did the QTH for all investigated adhesives. However, no statistically significant differences were found. The highest shrinkage was observed for Light Bond cured with HQTH (1.59 +/- 0.82%), and the lowest value was observed for Transbond XT cured with QTH (1.23 +/- 0.60%). There are no significant differences in polymerization shrinkage of the three investigated orthodontic adhesives when polymerized with a QTH or a HQTH.

Temperature increase during orthodontic bonding with different curing units using an infrared camera

Abstract Aim. To evaluate the effects of different curing units and light-tip tooth surface distances on the temperature increase generated during orthodontic bonding, using an infrared camera (IR) and artificial neural networks (ANN). Materials and methods. Fifty-two freshly extracted human premolar teeth were used. Metallic orthodontic brackets were bonded to the buccal surfaces of the teeth and thermal records were taken using an IR camera and ANN. Brackets were cured with a light-emitting diode (LED) and high intensity halogen (HQTH). Teeth were divided into four groups according to the curing units (LED and HQTH) and curing distances (from tooth surface and 10 mm away from tooth surface). The results were analyzed with analysis of variance (ANOVA) and the Tukey HSD test. Results. The ANOVA and Tukey HSD tests revealed that temperature changes were influenced by the type of light source and exposure times. All groups revealed significant differences between each other (p < 0.001). The highest surface temperature increase was gained from curing with a LED unit from the tooth surface (11.35°C ± 0.91°C). The lowest surface temperature increase was gained from curing with a HQTH unit 10 mm away from the tooth surface (2.57°C ± 0.6°C). Conclusion. The LED unit induced significantly higher temperature changes than did the HQTH. The temperature increase during orthodontic bonding was increased with long exposure time. A shorter light-tip tooth surface distance leads to greater increases in temperature.