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Featured researches published by Hakan El.


American Journal of Orthodontics and Dentofacial Orthopedics | 2011

Airway volume for different dentofacial skeletal patterns

Hakan El; Juan Martin Palomo

INTRODUCTION Our objective was to evaluate the nasal passage (NP) and oropharyngeal (OP) volumes of patients with different dentofacial skeletal patterns. METHODS The study sample consisted of 140 patients (70 boys, 70 girls), divided into 3 groups as Class I (1 ≤ ANB ≤ 3), Class II (ANB > 3), and Class III (ANB < 1), and then further divided into 4 groups as SNA angle ≥ 80°, SNA angle <80°, SNB angle ≥78°, and SNB angle < 78° to evaluate how the positional changes in the maxilla and the mandible affect the OP and NP variables. Differences between groups were determined by using the Kruskal-Wallis test. Correlations between the variables were tested with the Spearman correlation coefficient. The linear multiple regression test was applied to create a model for the airway volumes separately. RESULTS The OP volume of the Class II subjects (n = 50) was significantly lower when compared with that of the Class I (n = 46) and Class III subjects (n = 44). The only statistically significant difference for NP volume was observed between the Class I and Class II groups. The mean OP airway volume of subjects with retruded mandibular positions was statistically significantly smaller when compared with the subjects with higher SNB angles. The area of the most constricted region at the base of the tongue (minAx) had a high potential in explaining the OP volume, whereas the NP volume models were not as successful as the OP counterpart. However, minAx was also entered into the NP volume equations as an explanatory variable. CONCLUSIONS The OP airway volumes of Class II patients were smaller when compared with Class I and Class III patients. It was observed that mandibular position with respect to cranial base had an effect on the OP airway volume. The only significant difference for the NP volume was between the Class I and Class II groups, with a smaller volume observed for the Class II group.


Angle Orthodontist | 2010

Effects of extraction versus non-extraction treatment on oropharyngeal airway volume.

Manish Valiathan; Hakan El; Mark G. Hans; Martin Palomo

OBJECTIVE To compare the effects of extraction vs nonextraction orthodontic treatments on oropharyngeal airway volume. MATERIALS AND METHODS An existing patient database was screened for pretreatment (T0) and posttreatment (T1) cone beam computed tomography (CBCT) scans and complete medical histories. Twenty patients treated with removal of four premolars (ExtG) and 20 controls (NExtG), were matched for age, gender, ethnicity, height, weight, body mass index, and oropharyngeal (OP) volumes, among other variables. Constructed lateral cephalograms (three skeletal and four dental variables) and OP volumes were measured at T0 and T1 using Dolphin Imaging 11.0. Independent sample t-tests were used to compare the groups at T0 and the outcome variables at T1. Paired sample t-tests were used to compare the mean changes from T0 to T1. Statistical significance was set at P < or = .05. RESULTS Changes from T0 to T1 were found to be significant in both groups for CoA, CoGn, U1-FH, and IMPA. In the ExtG alone, U1-Na Perp and L1-Na Perp were also significantly different from T0 to T1. Despite the observed differences, no significant differences were found at the end of treatment between the mean OP volumes for either group (12,675.6 +/- 4483.6 for ExtG; 12,002.7 +/- 2857.0 for NExtG, P > .05). Similarly, the mean changes in OP volume (1082.6 mm(3) and 1701.1 mm(3) for ExtG and NExtG, respectively) and increase in mean minimal constricted axial areas (17.4 mm(2) and 1.9 mm(2) for ExtG and NExtG, respectively, P > .05) from T0 to T1 were not significant for the two groups. CONCLUSION Extraction of four premolars with retraction of incisors does not affect OP airway volume.


Journal of Oral and Maxillofacial Surgery | 2011

A 3-Dimensional Airway Analysis of an Obstructive Sleep Apnea Surgical Correction With Cone Beam Computed Tomography

Azime Sibel El; Hakan El; Juan Martin Palomo; Dale A. Baur

PURPOSE The purpose of this case report is to present cephalometric changes in the craniofacial region and volumetric changes in the oropharyngeal region of a patient diagnosed with obstructive sleep apnea syndrome after maxillomandibular advancement and genial tubercle advancement surgeries. MATERIALS AND METHODS Cone beam computed tomographic images were used to evaluate cephalometric changes in the craniofacial region and linear changes in the oropharyngeal region of the patient. RESULTS A patient with obstructive sleep apnea was treated successfully with maxillomandibular advancement and genial tubercle advancement surgery. Airway analysis showed a significant increase in the volume of the patients oropharynx after surgery. CONCLUSION Cone beam computed tomographic images are recommended for 3-dimensional airway evaluation in the treatment of obstructive sleep apnea syndrome.


Angle Orthodontist | 2014

Three-dimensional evaluation of upper airway following rapid maxillary expansion A CBCT study

Hakan El; Juan Martin Palomo

OBJECTIVES To evaluate, by using cone beam computed tomography, the skeletal, dental, oropharyngeal (OP) airway volume, and nasal passage (NP) volume changes that occur after rapid maxillary expansion (RME). MATERIALS AND METHODS Two groups were selected, each with 35 patients (15 males, 20 females), an RME group (mean age, 14.02 ± 1.46 years) and a control group (mean age, 14.10 ± 1.44 years). The RME group consisted of patients with maxillary constriction who were treated with Hyrax palatal expanders, and the control group comprised age- and sex-matched patients who underwent comprehensive orthodontic treatment without the use of a rapid maxillary expander. RESULTS All of the transverse skeletal (medial orbital width, lateral nasal width, maxillary width, and mandibular width) and interdental (intermolar, interpremolar, and intercanine) parameters were significantly enlarged in the RME group. A statistically significant increase in airway variables was seen in both groups between pretreatment (T0) and final records (T1). The mean increase of NP airway volume for the RME group (1719.9 ± 1510.7 mm(3)) was twofold compared with the control group (813.6 ± 1006.7 mm(3)), and no intergroup significant difference was found for the OP volume. CONCLUSIONS Rapid maxillary expansion creates a significant increase in nasal passage airway volume but no significant change in the oropharyngeal airway volume.


European Journal of Orthodontics | 2013

An airway study of different maxillary and mandibular sagittal positions.

Hakan El; Juan Martin Palomo

The aim of this study was to evaluate the oropharyngeal (OP) and nasal passage (NP) volumes along with various airway variables of patients with normal nasorespiratory functions having different dentofacial skeletal patterns and to evaluate the correlations between different variables and the airway. One hundred and one patients (57 males and 44 females, aged 14-18 years) having pre-treatment cone beam computed tomography images and complete medical records were selected. The patients were divided into five groups as Class I (CI, 81 ≥ SNA ≥ 77; 80 ≥ SNB ≥ 76; 3 ≥ ANB ≥ 1), Class II maxillary protrusion (CIIMaxP, SNA > 81; 80 ≥ SNB ≥ 76; ANB > 3), Class II mandibular retrusion (CIIMandR, 81 ≥ SNA ≥ 77; SNB < 76; ANB > 3), Class III maxillary retrusion (CIIIMaxR, SNA < 77; 80 ≥ SNB ≥ 76; ANB < 1), and Class III mandibular protrusion (CIIIMandP, 81 ≥ SNA ≥ 77; SNB > 80; ANB < 1). Posterior airway space, area of the most constricted region at the base of the tongue (minAx), and OP volume were significantly higher for the CIIIMandP group, whereas CIIMandR subjects had the lowest values. The only significant difference for the NP volume was between CI and CIIMandR groups where a smaller volume for the CIIMandR group was observed. The minAx was the variable that presented the best correlation with the OP airway volume. It seems that a detailed analysis of airway may prove to be a valuable diagnostic addition in orthodontics.


Journal of Oral and Maxillofacial Surgery | 2010

Skeletal and Dental Stability After Maxillary Distraction With a Rigid External Device in Adult Cleft Lip and Palate Patients

Muge Aksu; Banu Saglam-Aydinatay; Hakan El; Tulin Taner; Ilken Kocadereli; Gökhan Tunçbilek; Mehmet Emin Mavili

PURPOSE To evaluate skeletal and dental stability in adult cleft lip and palate patients treated with a rigid external distraction system at the end of distraction and during the postdistraction period. PATIENTS AND METHODS Lateral cephalograms of 7 patients were obtained before distraction, at the end of distraction, and during the postdistraction period. The mean age before distraction was 21.56 +/- 4.73 years. The mean follow-up was 37.3 +/- 12.4 months. RESULTS The assessment of findings showed that skeletal maxillary sagittal movement was achieved in a superoanterior direction. The maxillary depth angle and effective maxillary length increased significantly (2 degrees and 9 mm, respectively) after distraction, whereas the palatal plane angle increased by 8 degrees , resulting in an anterior movement of the maxilla with a counterclockwise rotation. The lower facial height showed no significant changes after distraction. The sagittal movement of the upper incisors and the angulation of the upper first molars increased significantly (4.5 mm and 5.5 degrees , respectively). During the postdistraction period, the maxilla showed a slight relapse (22%). The effective maxillary length decreased by 2 mm. The palatal plane angle almost returned to its original position, showing 7 degrees of clockwise rotation. The lower facial height remained stable. The upper incisors moved anteriorly and the upper first molars showed a significant mesioangular change during follow-up. CONCLUSIONS After distraction, significant maxillary advancement was achieved with a counterclockwise rotation. The upper incisors moved labially, and the upper first molars angulated mesially. After 3 years, a 22% relapse rate was seen in the maxilla. The counterclockwise rotation of the maxilla was returned to its original position. The upper incisors moved more anteriorly.


American Journal of Orthodontics and Dentofacial Orthopedics | 2010

Editor's Comment and Q&A: Measuring the airway in 3 dimensions: A reliability and accuracy study

Hakan El; Juan Martin Palomo

INTRODUCTION The aim of the study was to compare the reliability and accuracy of 3 commercially available digital imaging and communications in medicine (DICOM) viewers for measuring upper airway volumes. METHODS Thirty cone-beam computed tomography scans were randomly selected, and the upper airway volumes were calculated for both oropharynx and nasal passage. Dolphin3D (version 11, Dolphin Imaging & Management Solutions, Chatsworth, Calif), InVivoDental (version 4.0.70, Anatomage, San Jose, Calif), and OnDemand3D (version 1.0.1.8407, CyberMed, Seoul, Korea) were compared with a previously tested manual segmentation program called OrthoSegment (OS) (developed at the Department of Orthodontics at Case Western Reserve University, Cleveland, Ohio). The measurements were repeated after 2 weeks, and the ICC was used for the reliability tests. All commercially available programs were compared with the OS program by using regression analysis. The Pearson correlation was used to evaluate the correlation between the OS and the automatic segmentation programs. RESULTS The reliability was high for all programs. The highest correlation found was between the OS and Dolphin3D for the oropharynx, and between the OS and InVivoDental for nasal passage volume. A high correlation was found for all programs, but the results also showed statistically significant differences compared with the OS program. The programs also had inconsistencies among themselves. CONCLUSIONS The 3 commercially available DICOM viewers are highly reliable in their airway volume calculations and showed high correlation of results but poor accuracy, suggesting systematic errors.


American Journal of Orthodontics and Dentofacial Orthopedics | 2010

Effects of 2 types of facemasks on condylar position

Hakan El; Semra Ciger

INTRODUCTION The aim of this study was to compare Delaire and Grummons protraction facemasks with a new articulator system (Amtech MG1, American Technologies, Brazil) that can record condylar positions. METHODS Thirty-four patients treated with protraction facemask therapy were divided into 2 groups; 18 were treated with the Delaire facemask (DFM) and 16 with the Grummons facemask (GFM). The observation periods were 8.5 months for the DFM group and 10 months for the GFM group. Mandibular position indicator (MPI) recordings were taken with the new articulator system and evaluated before and after the protraction facemask therapies. RESULTS MPI recordings in the sagittal plane showed forward and downward movement from centric relation to maximum intercuspal position for both condyles at the beginning of treatment for most patients. After treatment, the discrepancy between centric relation and maximum intercuspation was less in the DFM group than in the GFM group. However, more compressive movement of the condyles through the glenoid fossa was observed in the DFM group. CONCLUSIONS Although the centric slide amount decreased more with the Delaire facemask compared with the Grummons facemask, patients treated with the Delaire facemask must be monitored for signs and symptoms of temporomandibular joint disorder.


Angle Orthodontist | 2017

Maxillary sinus volume in patients with impacted canines

Aslihan Zeynep Oz; Abdullah Alper Oz; Hakan El; Juan Martin Palomo

OBJECTIVES To evaluate the maxillary sinus volumes in unilaterally impacted canine patients and to compare the volumetric changes that occur after the eruption of canines to the dental arch using cone beam computed tomography (CBCT). MATERIALS AND METHODS Pre- (T0) and posttreatment (T1) CBCT records of 30 patients were used to calculate maxillary sinus volumes between the impacted and erupted canine sides. The InVivoDental 5.0 program was used to measure the volume of the maxillary sinuses. The distance from impacted canine cusp tip to the target point on the palatal plane was also measured. RESULTS Right maxillary sinus volume was statistically significantly smaller compared to that of the left maxillary sinus when the canine was impacted on the right side at T0. According to the T1 measurements there was no significant difference between the mean volumes of the impaction side and the contralateral side. The distance from the canine tip to its target point on the palatal plane were 17.17 mm, and the distance from the tip to the target point was 15.14 mm for the left- and right-side impacted canines, respectively, and there was a significant difference between the mean amount of change of both sides of maxillary sinuses after treatment of impacted canines. CONCLUSIONS Orthodontic treatment of impacted canines created a significant increase in maxillary sinus volume when the impacted canines were closer with respect to the maxillary sinus.


Turkish Journal of Orthodontics | 2014

The Comparison of Silver and Laser Soldering Techniques on Periodontal Tissues: A Preliminary Study

Ezgi Atik; Ceyda Kanlı Dursun; Hakan El; Tolga F. Tözüm; Semra Ciger

ABSTRACT Objective: The aim of this study was to compare the inflammatory effects of conventional and laser soldering methods on periodontal tissues in orthodontics. Materials and Method: Forty specimens were acquired from 10 patients whose treatment plan consisted of extraction of 4 first premolars. Before performing the extractions, a transpalatal arch (TPA) for the upper first molars and a lingual arch for the lower first molars were placed for anchorage purposes. Upper left and lower right first molar bands were soldered using the laser welding (LW) technique, and upper right and lower left first molar bands were soldered using the conventional silver soldering technique (CSS). Gingival crevicular fluid (GCF) analysis was used for determining the effects of welding procedures on periodontal tissues. All variables were analyzed by nonparametric tests. Results: Myeloperoxidase levels ranged between 2.46 and 3.56 for the CSS group and between 2.20 and 3.39 for the LW group; nitric oxide levels ranged bet...

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Juan Martin Palomo

Case Western Reserve University

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Manish Valiathan

Case Western Reserve University

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Mark G. Hans

Case Western Reserve University

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Martin Palomo

Case Western Reserve University

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