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Serkan Dundar,1 Abubekir Eltas,2 Sema S Hakki,3 Sıddık Malkoc,4 M Ozay Uslu,2 Mehmet Tuzcu,5 James Komorowski,6 I Hanifi Ozercan,7 Fatih Akdemir,8 Kazim Sahin9 1Department of Periodontology, Faculty of Dentistry, Firat University, Elazig, 2Department of Periodontology, Faculty of Dentistry, Inonu University, Malatya, 3Department of Periodontology, Faculty of Dentistry, Selcuk University, Konya, 4Department of Orthodontics, Faculty of Dentistry, Inonu University, Malatya, 5Department of Biology, Faculty of Science, Firat University, Elazig, Turkey; 6Research & Development, Nutrition 21 Inc., Purchase, NY, USA; 7Department of Pathology, Faculty of Medicine, 8Department of Animal Nutrition, Faculty of Fisheries, Inonu University, Malatya, 9Department of Animal Nutrition, Faculty of Veterinary Medicine, Firat University, Elazig, Turkey Abstract: The purpose of this study was to induce experimental periodontitis in rats previously fed diets containing arginine silicate inositol (ASI) complex and examine the biochemical, immunological, and radiological effects. Fifty two 8-week-old female Sprague Dawley rats were equally divided into four groups. The control group included those fed a standard rat diet with no operation performed during the experiment. The periodontitis, ASI I, and ASI II groups were subjected to experimental periodontitis induction for 11 days after being fed a standard rat diet alone, a diet containing 1.81 g/kg ASI complex, or a diet containing 3.62 g/kg ASI complex, respectively, for 8 weeks. Throughout the 11-day duration of periodontitis induction, all rats were fed standard feed. The rats were euthanized on the eleventh day, and their tissue and blood samples were collected. In the periodontitis group, elevated tissue destruction parameters and reduced tissue formation parameters were found, as compared to the ASI groups. Levels of enzymes, cytokines, and mediators associated with periodontal tissue destruction were lower in rats fed a diet containing ASI complex after experimental periodontitis. These results indicate that ASI complex could be an alternative agent for host modulation. Keywords: arginine silicate inositol complex, experimental periodontitis, host modulation, micro-computed tomography, periodontal infection

The aim of this study was to assess the effects of rapid maxillary expansion (RME) and surgical assisted rapid maxillary expansion (SARME) on nasopharyngeal area. The study group consisted of 30 subjects in the permanent dentition who had both maxillary constriction and a posterior cross-bite. The patients were divided into two groups, RME and SARME. The subjects in the RME group consisted of 15 patients (eight girls, seven boys) whose average age was 12.1 ± 1.1 years. The SARME group also consisted of 15 patients (eight boys, seven girls) whose mean age was 18.4 ± 1.4 years. An acrylic bonded RME appliance was used in both groups. Surgery was performed using lateral cortical osteotomies in the SARME group. The nasopharyngeal and respiratory area was determined using a digital planimeter on lateral cephalometric radiographs taken before and after RME. Nasal cavity width was evaluated on postero-anterior radiographs. Nasal dimension was measured using planimeter measurements of the respiratory and nasopharyngeal areas before and after treatment. The data obtained were analyzed using SPSS. Comparisons within the groups were carried out with paired t-tests and comparisons between the groups were with a Student's t-test. In both groups, the respiratory area and the ratio of the respiratory area to nasopharyngeal (RA/NA) area increased following RME. There were no statistically significant differences between the groups. Nasal cavity width and maxillary width also increased, but the difference between the groups was not significant. Following RME, various differences in both the maxilla and surrounding bones occurred and nasal width increased with a decrease in nasal airway resistance. At the end of treatment there were increases in the width of the nasal floor near the midpalatal suture and nasal cavity. As the maxillary structures separated, the outer walls of the nasal cavity moved laterally resulting in an increase in internasal volume. Nasal resistance decreased and respiratory area increased in patients treated with RME. [ABSTRACT FROM AUTHOR]

Introduction: The COVID-19 pandemic has emerged as one of the most formidable global crises, leading to the disruptions to education systems worldwide and impacting learning attitudes and psychological well-being of various learner groups, including university students. In this context, students' appraisals of adverse learning situations play a key role. It is not just the learning situation, but rather students' appraisal of it which impacts their emotions, attitudes, and behaviors in academic context. The aim of the present study was to investigate how university students' challenge and threat appraisals were related to emotional learning experiences and learning outcomes during the COVID-19 pandemic. Furthermore, the study focuses on the role of personal and external resources for learning in this context., Methods: Altogether, 428 students, who attended a Psychology lecture at one Austrian university, filled in a questionnaire about their challenge and threat appraisals of learning circumstances during the COVID-19 pandemic, achievement emotions they experienced during this time as well as gender, proneness to anxiety, academic self-concept, and learning resources. Additionally, students' performance in the examination was recorded., Results: The structural equation model emphasizes a crucial role of challenge and threat appraisals for students' achievement emotions in learning and exam preparation during the COVID-19 pandemic. Challenge appraisals were the strongest predictor for pleasant emotions and threat appraisals were strongest predictor for unpleasant emotions. Proneness to anxiety was related to threat appraisal as well as to experience of more unpleasant and, surprisingly, to positive emotions in adverse learning situation. Academic self-concept and learning resources were identified as important resources for learning in adverse learning situation. Unpleasant achievement emotions were directly and negatively related to academic performance and may thus be seen as a critical variable and crucial obstacle to academic performance., Discussion: The present study provides implications for learning and instructions which could be implemented by universities in order to support learning and learning attitudes among university students in adverse learning situations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Malkoc, Macher, Hasenhütl and Paechter.)

The COVID-19 summer semester 2020 posed many challenges and uncertainties, quite unexpectedly and suddenly. In a sample of 314 psychology students, it was investigated how they experienced learning and preparing for an end-of-semester exam, which emotions and strain they experienced, how academic performance was affected, and how personal antecedents of learning as important facets of a learner's identity could support or prevent overcoming adverse circumstances of learning. The participants of the study filled in a questionnaire about their achievement emotions and strain they experienced during learning and exam preparation as well as academic self-concept, motivation, gender, proneness to anxiety. Points achieved in the exam were also recorded. The interaction between the variables was investigated by a structural equation model. It showed that the investigated variables can be distinguished into two groups, variables that contribute mainly negatively to performance and variables with a positive contribution. Strain experienced during the COVID-19 pandemic and unpleasant emotions "belong together" in the sense that they inhibit academic performance directly or indirectly. Proneness to anxiety in academic situations was related with higher levels of mental, emotional, and physical disturbances due to the COVID-19 situation. In contrast, motivation and a high academic self-concept acted as support for learning and performance. Both contribute to pleasant achievement emotions in the learning situation; moreover, motivation had a direct relationship to academic performance. The results from the present study do not only provide insight into important students' personal dispositions and their role for learning in adverse circumstances but also give advice how to strengthen students for successful learning., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Paechter, Phan-Lesti, Ertl, Macher, Malkoc and Papousek.)

The reported beneficial effects of boron on mineralized tissues in animals and humans vary. Thus, a study was performed to assess whether the variability was the result of different forms of boron supplementation, method of supplementation, and increased adiposity of the rabbit experimental model. Thirty-one female New Zealand White rabbits, (aged 8 months, 2-2.5 kg weight) were fed a grain-based high energy diet containing 11.76 MJ/kg (2850 kcal/kg) and 3.88 mg boron/kg. The rabbits were randomly divided into four treatment groups: Control group was not supplemented with boron (n:7; C), and three groups supplemented with 30 mg boron/L in drinking water in the forms of borax decahydrate (Na2O4B7 10H2O, n:10; BD), borax anhydrous (Na2O4B7, n:7; Bah) or boric acid (H2BO3, n:7; BA). Cone beam micro computed tomographic (micro-CT), histological and elemental analysis was used to evaluate the bones/teeth. Results of the experiments demonstrated that boron supplementation had beneficial effects on mineralized tissue but varied with the type of treatment. Mineral density of the femur was increased by the Bah and BA treatments (p < 0.001), but only BA increased mineral density in the tibia (p = 0.015). In incisor teeth, mineral density of dentin was increased by all boron treatments (p < 0.001), and mineral density of enamel was increased by the BD and Bah treatments. Mineral analysis found that all boron treatments increased the boron concentration in tibia and femur. In the tibia, both the BD and Bah treatments decreased the iron concentration, and the BD treatment decreased the magnesium concentration. Sodium and zinc concentrations in the tibia were decreased by the Bah and BA treatments. The boron treatments did not significantly affect the calcium, copper, molybdenum, potassium phosphorus, and sulfur concentrations. The findings show that boron supplementation can have beneficial effects on mineralized tissues in an animal model with increased adiposity, which is a model of increased inflammatory stress. However, this effect varies with the form of boron supplemented, the method of supplementation, and the mineralized tissue examined., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

The aim of this study is to find out the certain heavy-metal levels in the feathers of cinereous vulture (Aegypius monachus L.), which is a threatened species. The feathers of the cinereous vultures were collected from the breeding areas in Sündiken and Türkmenbaba Mountains. To avoid misleading results, vanes and calamuses of the rectrices were evaluated separately in terms of their As, Cd, Cr, Cu, Hg, Ni, Pb and Zn contents. ICP-OES was used to analyse the metal levels in feathers which belonged to 43 different individuals. All of the heavy-metal concentrations except for Cu were higher in vanes than in calamuses. The mean levels of Cd (0.254 ± 1.589 μg/g d.w. in the calamus and 0.334 ± 0.156 μg/g d.w. in the vane), Cr (6.536 ± 6.378 μg/g d.w. in the vane), Ni (11.886 ± 10.891 μg/g d.w. in the vane) and Pb (5.671 ± 3.884 μg/g d.w. in the vane) exceeded the threshold values for the birds. As a result, we recommend further studies to understand the effects of the heavy metals on the population of the species.

Introduction: The aim of this study was to use microcomputed tomography to evaluate the effects on white spot lesions of 3 remineralizing agents compared with artificial saliva (Inonu University, Malatya, Turkey). The agents were GC Tooth Mousse (GC International, Itabashi-ku, Tokyo, Japan), 50-ppm sodium fluoride solution (Inonu University, Malatya, Turkey), and Clinpro 5000 (3M ESPE Dental Products (St Paul, Minn). The experimental and control teeth were stored in artificial saliva., Methods: Forty-four extracted premolars were divided into 4 groups of 11 teeth each (3 experimental groups and 1 control group). After white spot lesions were created on the teeth, a remineralizing agent was applied. Microcomputed tomography scanning was performed at the following times: T0 (sound enamel), T1 (day 0, when the white spot lesion was formed), T2 (day 15), and T3 (day 30). Volume, depth, surface area, and mineral density changes of the white spot lesions were evaluated at different time points using CTAn software (SkyScan; Bruker, Kontich, Belgium)., Results: GC Tooth Mousse and Clinpro 5000 improved all measurements after 30 days. However, Clinpro 5000 was not as effective in reducing lesion depth as it was in the other parameters. The artificial saliva group and the 50-ppm sodium fluoride solution did not show significant effects in the regression of the white spot lesions at the end of the 30-day experiment., Conclusions: GC Tooth Mousse and Clinpro 5000 were more effective in remineralization of white spot lesions than sodium fluoride solution and artificial saliva. They can be preferred for use clinically. Microcomputed tomography is a novel and effective method that shows promise in accurately evaluating white spot lesions and remineralization., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of our study was to investigate whether the parameters of ideal angles, ratios, and divine proportions that have been previously mentioned in the literature influence the aesthetic evaluation of Turkish adolescents., Materials and Methods: A total of sixty patients (30 males and 30 females) were enrolled in this study. Ages of the subjects ranged from 9 to 17. Pre-treatment extra-oral photographs were taken to evaluate facial aesthetics. Two distinct panels consisting of 50 orthodontists and 50 laypersons were created for scoring the photographs of the patients. Scoring was performed using the VAS scale. Twenty-seven ratios and 19 divine proportions were measured in frontal photographs, and 26 angles were measured in profile photographs., Results: Pearson correlation was used to determine the relationship between the photograph analysis measurements and VAS scores, and then regression analyses were performed to disclose to what extent significant values may warrant the term beauty., Conclusion: As a result of our investigations, none of the golden proportions was associated with facial aesthetics according to both orthodontists and laypersons. According to other angles and ratios that were measured, it was determined that orthodontists noticed the sagittal position of the lower jaw, the distance between the eyes and length of the face, whereas laypersons noticed only the distance between the eyes and length of the face., Level of Evidence V: This journal requires that the authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

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.

The aim of this retrospective study was to evaluate the treatment outcome of lower incisor extraction and to compare it with premolar extraction and non-extraction treatment. The sample consisted of 60 subjects with Class I malocclusion and moderate crowding. The sample was separated into three groups: extraction of a lower incisor group, extraction of a four first premolar group and a non-extraction group. All groups involved 13 girls and 7 boys with a total of 20 patients. The Peer assessment rating (PAR) index was applied to a patient's pre-treatment (T1) and post-treatment (T2) dental casts. T1 dental casts were also used for determining Bolton discrepancy. One-way analysis of variance and post hoc Tukey HSD tests were used for statistical analysis. For the mean percentage PAR score reduction for each group, there was one significant difference seen between the lower incisor extraction group and the non-extraction group (P = 0.047). For the mean anterior ratios, there were significant differences among premolar extraction group versus non-extraction group (P = 0.042) and non-extraction group versus lower incisor extraction group (P = 0.000). For the mean overall ratios, there were significant differences among the premolar extraction group versus lower incisor extraction group (P = 0.048) and the non-extraction group versus lower incisor extraction group (P = 0.001). Orthodontic treatment without extraction has a better treatment outcome than the four-first premolar extraction and single lower incisor extraction protocols in Class I cases with moderate to severe mandibular anterior crowding.

Introduction: The aim of this study was to evaluate the cytotoxicity of 3 orthodontic acrylic materials and 2 manipulation methods., Methods: The orthodontic acrylic materials Orthocryl EQ (Dentaurum, Ispringen, Germany), Orthoplast (Vertex Dental, Zeist, The Netherlands), and O-80 (Imicryl, Konya, Turkey) were prepared with 2 polymerization methods (doughing and spray on). Totally, 60 cylinders (5 × 2 mm), fabricated by using a different acrylic and method, were divided into 6 groups. Gingival fibroblasts were isolated from gingival connective tissue of systemically healthy subjects. Materials were incubated in Dulbecco's modified eagle's medium culture medium (Biological Industries, Beit Haemek, Israel) 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). Gingival fibroblasts were maintained with Dulbecco's modified eagle medium containing 10% fetal bovine serum. A real-time cell analyzer (RT-CES, xCELLigence; Roche Applied Science, Mannheim, Germany, and ACEA Biosciences, San Diego, Calif) was used to evaluate cell survival. After seeding 200 μL of the cell suspensions into the wells (20,000 cells/well) of the E-plate 96, gingival fibroblasts were treated with bioactive components released by the acrylic materials (1/1 and 1/2 dilutions) and monitored every 15 minutes for 121 hours. For the proliferation experiments, the statistical analyses used were 1-way analysis of variance (ANOVA) and Tukey-Kramer multiple comparisons tests., Results: There was no significant difference between the cell indexes of the control and study groups for the 1/1 and 1/2 dilutions at 21 and 32 hours. When evaluated at 68 hours, all 1/2 dilutions of acrylic materials showed statistically insignificant differences (P >0.05) except for Orthoplast (P <0.05). But all acrylic materials were different from the control group in the 1/1 dilutions (P <0.001). At 121 hours, all test groups were significantly different from the untreated control group (P <0.001)., Conclusions: The results indicate that the long cycle increased the cytotoxicity of the tested materials, and there was no significant difference between the spray-on and doughing methods on cytotoxicity., (Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

A detailed study was conducted to determine the current status of the heavy metals Cd, Cu, Cr, Fe, Hg, Mn, Ni, Pb, and Zn in Eskisehir, Turkey. The 15 different locations (n =270) studied were specifically selected to identify the effects of soil pollution on the tramway, which has been in service since December 2004 for public transportation in Eskisehir. The samples were taken from three different lines: tramway-only lines, traffic-only lines, and both traffic and tramway lines. The pollution level was estimated based on the geoaccumulation index (I(geo)), the enrichment factor (EF), the pollution index, and the integrated pollution index (IPI). The values for the IPI were in the following order: Pb > Zn > Cu > Fe > Mn > Ni > Cr > Cd, but mercury was not detected at any sample point. These indexes for metals in the soils under consideration correlated with either low or median levels of pollution. In addition, descriptive statistics were provided for the heavy metals under consideration, and box-plots were constructed and interpreted for all measured indices., (Copyright © 2010 SETAC.)

Objective: To evaluate the cytotoxic effects of three different resin-modified orthodontic band adhesives., Materials and Methods: Three resin-modified orthodontic band adhesives (Bisco Ortho Band Paste LC, Multi-Cure Glass Ionomer Band Cement, and Transbond Plus Light Cure Band Adhesive) were prepared and the samples were extracted in 3 mL of Basal Medium Eagle with 10% newborn calf serum for 24 hours. The L929 cells were plated (25,000 cells/mL) in wells of 96-well dishes and maintained in a humidified incubator for 24 hours at 37 degrees C, 5% CO(2), and 95% air. After 24-hour incubation of the cells, the incubation medium was replaced by the immersed medium in which the samples were stored. Then L929 cells were incubated in contact with eluates for 24 hours. The cell mitochondrial activity was evaluated by the methyltetrazolium test. Twelve wells were used for each specimen, and methyltetrazolium tests were applied two times. The data were statistically analyzed using one-way analysis of variance and Tukey Honestly Significantly Different tests., Results: Results with L929 fibroblasts demonstrated that all freshly prepared resin-modified orthodontic band adhesive materials reduced vital cell numbers (P > .05), in comparison to the control group. Our data demonstrate that all materials showed significant cytotoxicity compared to the control group., Conclusions: The results indicate that all materials showed significant cytotoxicity compared to the control group, and further studies using different test methods are needed for all resin-modified orthodontic band adhesives.

Objectives: To evaluate the cytotoxic effects of five different light-cured orthodontic bonding composites., Materials and Methods: The orthodontic composites Heliosit Orthodontic (Ivoclar), Transbond XT (3M Unitek), Bisco ORTHO (Bisco), Light Bond (Reliance), and Quick Cure (Reliance) were prepared, and the samples were extracted in 3 mL of BME (Basal Medium Eagle) with 10% newborn calf serum for 24 hours. The L929 cells were plated (25,000 cells/mL) in a 96-well dish and maintained in a humidified incubator for 24 hours at 37 degrees C, 5% CO(2), and 95% air. After 24 hours of incubation of the cells, the incubation medium was replaced by the immersed medium in which the samples were stored. Then, L929 cells were incubated in contact with eluates for 24 hours. The cell mitochondrial activity was evaluated by the methyl tetrazolium (MTT) test. Twelve wells were used for each specimen, and the MTT tests were applied two times. The data were statistically analyzed by one-way analysis of variance (ANOVA) and Tukey HSD tests., Results: Results with L929 fibroblasts demonstrated that except for Transbond XT, freshly prepared composite materials did not reduce vital cell numbers (P > .05) compared with the control group. Our data demonstrate that Transbond XT showed significant cytotoxicity compared with the control group., Conclusion: Results indicate that tested orthodontic bonding composites are suitable for clinical application, but that further studies using different test methods are needed for Transbond XT.

Introduction: The aims of this study were (1) to establish cephalometric norms from submentovertex (SMV) radiographs for young Anatolian Turkish adults and (2) to identify possible sex differences between men and women., Methods: SMV cephalograms were taken of 50 nongrowing Turkish adults (25 men, mean age, 23.06 +/- 2.30 years; 25 women, mean age, 22.10 +/- 2.04 years). All had normal occlusions and well-balanced faces. Five angular and 10 linear measurements were made on each radiograph. For each variable, arithmetic mean and standard deviation minimum and maximum values were calculated. Independent-sample t tests were performed for the sex comparisons. Cephalometric angular and linear norms for Turkish adults were determined by using the Lew-Tay SMV cephalometric analysis. SMV cephalometric standards for Turkish adults were also developed., Results: Generally, our measurements were similar to the Lew-Tay SMV norms. Most Turkish SMV cephalometric measurements showed statistically significant sex differences. Comparison between Turkish men and women indicated larger measurements for men in all investigated linear measurements., Conclusions: SMV cephalometric norms are useful in the diagnosis of mandibular asymmetries and the treatment of dentofacial orthopedics in Turkish patients.

The aim of the present study was to determine whether the application of different primers containing antibacterial agents (Micro Prime, Seal&Protect, and Gluma Desensitizer) 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 (27.98 +/- 8.73 MPa) and the control (35.15 +/- 7.85 MPa) (P > 0.05). However, Gluma (21.61 +/- 7.96 MPa) and Micro Prime (14.89 +/- 5.55 MPa) caused a decrease in bond strength (P < 0.05). No statistically significant difference was observed between Seal&Protect and Gluma (P > 0.05). As triclosan containing Seal&Protect 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.

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.

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.

Orthodontic forced eruption may be a suitable approach without risking the esthetic appearance in tooth fracture below the gingival attachment or alveolar bone crest. Extrusion of such teeth allows elevating the fracture line above the epithelial attachment and so the proper finishing margins can be prepared. Restoration after orthodontic eruption may present a more conservative treatment choice in young patients compared with the prosthetic restoration after extraction. This case describes a multidisciplinary approach using the orthodontic forced eruption facilitating the composite restoration of a fractured upper permanent central incisor.

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.

Interdental clefts or invaginations contribute to orthodontic relapse and poor periodontal health in extraction cases. These clefts or invaginations can be removed both by electrosurgical or conventional surgical gingivectomy techniques. This study investigates and compares the efficacy of two different techniques to remove gingival clefts with respect to periodontal health and patient tolerance. Twenty-two patients (mean age, 15.7 years) with bilateral gingival clefts participated in this study. In each patient, the gingival invaginations were removed by gingivectomy using electrosurgery on one side and conventional surgery on the contralateral side. The length and depth of the invaginations, the gingival index of the adjacent teeth, and the changes in visual analogue scale scores were recorded before and after the operation for both groups. Mann-Whitney U-test and Wilcoxon tests were used to analyze the data statistically. The results showed significant improvement in invagination depth and length and gingival index scores for both techniques. There were no statistical differences between the two gingivectomy techniques with respect to gingival health and patient tolerance. Both techniques can be used to remove the gingival invaginations efficiently.

This article evaluates the usage of distraction osteogenesis (DO) in the treatment of cleft alveoli. The procedure was carried out on eight alveolar clefts of five patients between the ages of 17 and 25 years. Three patients had bilateral alveolar clefts (BAC) and two patients had unilateral alveolar clefts (UAC). DO was carried out bilateral to the palatal segments for the BAC patients and unilateral to the lesser segment for the UAC patients. A custom-made tooth-borne distractor was used. The average amount of distraction was eight mm (range, 5-11.5 mm). The average amount of distal movement of the anchorage teeth was 0.8 mm (range, 0-2 mm). The average amount of inclination changes of the transport segments and anchorage teeth was 7.6 degrees (range, 2-17.5 degrees) and 3.3 degrees (range, 0-9 degrees), respectively. Two important problems were observed attributable to the method. First, the transport segment was docked in a more superior position at the end of distraction process. This undesirable movement also changed the inclination of the teeth in the transport segment and increased tooth tipping. Removing the device in the second week of the consolidation period and retracting the segment to its ideal position orthodontically solved these problems. Second, the bony defect on the nasal side of the alveolar cleft could not be completely closed. This method for repairing small or large alveolar clefts is a simple, cost-effective, and useful treatment option. However, repairing the alveolar cleft without grafts seems to be impossible when using a tooth-borne device.

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.