PubMed Health⌕ Search

Biomedical subjects

Erol Akin

Publications and source records attributed to Erol Akin.

12 recordsLinked to original sources

Effects of interferon-gamma on bone remodeling during experimental tooth movement.

OBJECTIVE: To determine the effects of interferon-gamma (IFN-gamma) on bone remodeling during orthodontic tooth movement. MATERIALS AND METHODS: Thirty adult male Sprague Dawley rats were randomly categorized into five groups. IFN-gamma was administered in three different doses (0.01, 0.02, and 0.05 microg/20 microL) and the remaining two groups served as control. Mandibular first molars were moved mesially by means of Ni-Ti closed coil springs in all groups. The results were evaluated histomorphometrically, and parameters of trabecular bone volume (BV/TV), trabecular bone number (Tr.N), and trabecular separation (Tr.Sep) were observed at the interradicular bone area of the mandibular first molars. RESULTS: Increases in BV/TV and Tr.N and decreases in Tr.Sep revealed the antiosteoclastic activity of IFN-gamma. CONCLUSION: IFN-gamma administration may be useful clinically for anchorage control.

Animals↗

Real-time balanced turbo field echo cine-magnetic resonance imaging evaluation of tongue movements during deglutition in subjects with anterior open bite.

INTRODUCTION: The aim of this study was to evaluate tongue movements in subjects with anterior dental open bites during deglutition by using real-time balanced turbo field echo cine-magnetic resonance imaging. METHODS: The study included 28 subjects. Two groups were formed according to the presence of anterior open bite (at least 2 mm). The open-bite group (OBG) consisted of 18 patients (14 girls, 4 boys) with a mean age of 14.5 +/- 2.7 years. The control group (CG) consisted of 10 patients (5 girls, 5 boys) with a mean age of 14.5 +/- 2.6 years. We evaluated deglutition during 3 stages: oral (stage 1), pharyngeal (stage 2), and esophageal stage (3). RESULTS: Results indicated that (1) in the OBG, from stage 2 to stage 3, the anterior portion of the tongue dorsum was elevated [corrected] whereas its midportion was lowered [corrected]; (2) in the CG, its posterior portion was lowered [corrected] from stage 2 to stage 3; (3) in the CG, the tongue tip was positioned more posteriorly [corrected] at stage 2 than at stage 1; (4) in the OBG, the tongue tip moved more anteriorly in all stages of deglutition than in the CG. CONCLUSIONS: Compensatory tongue functions occur in patients with anterior dental open bites. Dynamic MRI is a promising tool for evaluating swallowing patterns in these patients.

Adolescent↗

Use of zygomatic anchors during rapid canine distalization: a preliminary case report.

Rapid canine distalization is a technique involving periodontal ligament distraction. The primary aim of this technique is to distalize the canines without anchorage loss and to shorten the duration of orthodontic treatment. After the rapid canine distalization, the healing process of the periodontal ligament is similar to rapid palatal expansion and requires a consolidation period. The long consolidation period of the technique conflicts with the second aim. Skeletal anchorage systems seem to compensate for this conflict because they can be also used for retraction of incisors during consolidation period. This case report presents the orthodontic treatment of a 16-year-old female, who had a bimaxillary retrusion and a dental Class II division I malocclusion. Upper first premolars were extracted and, while the canines were being distalized rapidly by periodontal ligament distraction, the incisors were retracted using a zygomatic anchorage system. The treatment of the patient was completed in five months without any anchorage loss.

Adolescent↗

Initial effects of the tongue crib on tongue movements during deglutition: a Cine-Magnetic resonance imaging study.

The objective of this study was to investigate the initial effects of a tongue crib on tongue movements during deglutition by using real time balanced turbo field echo (B-TFE) Cine-MR imaging. A total of 21 patients were evaluated in this study. The open-bite group (OBG) consisted of 11 patients (seven girls, four boys) who had a mean age of 11.09 +/- 2.02 years and a mean overbite of -5.14 +/- 1.83 mm. These patients were evaluated initially (T1) and while wearing a tongue crib (T2). A total of 10 patients (five girls, five boys) with a mean age of 14.5 +/- 2.6 years and with a mean overbite of 1.6 +/- 0.5 mm served as controls (CG), and only initial records were obtained from these patients. T2 was compared with T1 and CG. T1 was also compared with CG. We evaluated deglutition during three stages matching oral (1), pharyngeal (2), and esophageal (3) stages. Our results indicated that the tongue's tip positioned more posteriorly when the crib was in place (T2) compared with both T1 and CG; the anterior portion of the tongue's dorsum was at a lower position in T2 compared with both T1 and CG at stage 3; the midportion of the tongue's dorsum was at a lower position in T2 than in T1 and CG at stages 1 and 2. To compensate for the posterior position of the tongue's tip (caused by the tongue crib), adaptive changes occurred in the anterior and midportions of the dorsum of the tongue.

Adaptation, Physiological↗

Forsus Nitinol Flat Spring and Jasper Jumper corrections of Class II division 1 malocclusions.

OBJECTIVE: To compare the effects of Forsus Nitinol Flat Spring (FNFS) and Jasper Jumper (JJ) in the correction of Class II division I malocclusions. MATERIALS AND METHODS: Our research was conducted on 48 adolescents, who had a normal or horizontal growth pattern and retrognathic mandible. The patients were divided into three equal groups randomly. First group was treated with FNFS, and the second group was treated with JJ appliances, whereas the third group was the control group. Lateral cephalograms and study models were obtained after the leveling phase and at time of the removal of the appliances. RESULTS: Cephalometric analysis revealed that both the appliances stimulated mandibular growth, increased the anterior face height because of the lower face, and elongated the posterior face height because of the growth of temporomandibular joint. Maxillary central incisors were extruded, retruded, and distally tipped. Contrarily, intrusion, protrusion, and labial tipping were observed in the mandibular central incisors. Distal movement and intrusion of the maxillary first molars and mesial movement and extrusion of the mandibular first molars were the other dental alterations. Overjet and overbite were decreased, and a Class I molar relationship and improvement in the profile were attained in both treatment groups. Cast model analysis showed expansion in the maxillary and mandibular dental arches. CONCLUSIONS: Both the appliances were effective in the treatment of Class II malocclusion and revealed nearly same alterations in the skeletal, dental, and soft tissue parameters.

Activator Appliances↗

Effects of a segmented removable appliance in molar distalization.

The aim of the present investigation was to evaluate the skeletal and dentoalveolar treatment effects of a segmented removable appliance [removable molar distalizer (RMD)] for molar distalization. The study was conducted on 28 patients (12 females and 16 males), with a mean age of 11.8 years. All presented with a skeletal Class I malocclusion and a bilateral dental Class II molar relationship. The pre- and post-distalization records included lateral head films, study models and standard photographs. The findings were evaluated with a paired samples t-test. The average maxillary first molar distalization with the RMD was 3.98 mm, with 4.61 degrees of distal tipping. The maxillary second premolars drifted distally 2.13 mm on average with 1.54 degrees of distal tipping, while the maxillary first premolars showed 1.23 mm of mesial movement and 1.98 degrees of mesial tipping. The incisors protruded 1.09 mm with 1.27 degrees of labial tipping. The RMD was effective in distal molar movement and all patients attained a bilateral Class I molar relationship in an average period of 4.5 months. Hygiene problems and mucosal irritations, frequently found with fixed intraoral distalization techniques, were not observed during the distalization period.

Cephalometry↗

Dynamic MRI evaluation of tongue posture and deglutitive movements in a surgically corrected open bite.

Tongue thrust usually develops in the presence of anterior open bite in order to achieve anterior valve function. In the literature, tongue thrust is described both as the result and the cause of open bite. If it is an adaptation to malocclusion, then tongue posture and deglutitive tongue movements should change after treatment. In this case report, an adult who had skeletal open bite and Class II malocclusion caused by mandibular retrusion was treated surgically. The mandible was advanced in a forward and upward direction with a sagittal split osteotomy. The open bite and Class II malocclusion were corrected and an increase in the posterior airway space (PAS) was observed. Pretreatment and posttreatment dynamic magnetic resonance imaging (MRI) revealed that tongue tip was retruded behind the incisors and contact of the tongue with the palate increased. It was also determined that the anterior and middle portions descended, whereas the posterior portion was elevated at all stages. Advancement of the mandible, correction of open bite, and an increase in PAS affected not only the tongue posture and deglutitive movements, but also the breathing pattern of the patient.

Adult↗

Dentofacial effects of asymmetric headgear and cervical headgear with removable plate on unilateral molar distalization.

Cervical headgear (CHG) is used widely in the treatment of Class II anomalies. Asymmetric headgear (AHG) is an alternative treatment for the correction of unilateral Class II dental relationships. The purpose of this investigation was to compare the effects of AHG with those of a CHG combined with a removable plate in unilateral first molar distalization. The study consisted of 20 patients with unilateral Class II molar relationship (12 girls and eight boys). One group of 10 patients was treated with an AHG, and a second group of 10 patients was treated with a CHG and a removable plate. Lateral cephalograms and basilar radiographs were taken before and after molar distalization. It was found that distalization and distal tipping of molar on the passive side was less in the CHG and removable plate (CHG-RP) group. Distalization and distal tipping of the second premolar on the distalization side was also reduced in this group. Incisors were retruded in both groups but were retruded more in the CHG-RP group.

Adolescent↗

Mandibular distraction with MD-DOS device.

Distraction osteogenesis is an alternative treatment method for the correction of mandibular hypoplasia. In this case report, mandibular distraction with a dynamic osteosynthesis system (MD-DOS) was performed to gradually lengthen the mandible of a patient who had a severe hypoplastic mandible. The patient underwent intraoral bilateral mandibular distraction osteogenesis. The latency period after the operation was seven days. The distraction was performed three times daily for 14 days at the rate of 0.33 mm each time. Subsequent retention was nine weeks. The patient's mandible was elongated successfully and a satisfactory profile and occlusion was achieved.

Adult↗

Effects of nitric oxide in orthodontic tooth movement in rats.

The purpose of this study was to evaluate the role of nitric oxide (NO) in orthodontic tooth movement in rats. Nomega-nitro-L-arginine methyl ester (L-NAME) was used as NO synthase (NOS) inhibitor, and nitro-L-arginine (NLA) was used as NOS precursor. Fifty-four Sprague-Dawley rats were divided into 3 equal groups, and each group was divided into 3 subgroups. In the first 8 subgroups, 20 g of force was applied to the maxillary incisors with a spring. NLA was administered in the first 3 subgroups at 10(-4), 10(-5) and 10(-6) mol/L (20 microL/12 hours), respectively. L-NAME was administered in the next 3 subgroups with the same order, amount, and prescription. The last 3 subgroups were evaluated as control groups; in the seventh subgroup, 0.9% NaCl (saline solution) was injected (20 microL/12 hours). Only the force was administered in the eighth subgroup, and no chemical solution or orthodontic force was used in the last subgroup. The rats were killed on the fifth day of the experiment. Their premaxillae were dissected, and tissue sections were obtained from the coronal, middle, and apical thirds of the incisor roots. Multinuclear osteoclasts, Howship's lacunae, capillary vascularization, and orthodontic tooth movement were significantly increased in the NLA groups compared with the L-NAME and control groups.

Animals↗

Initial intrusion of the molars in the treatment of anterior open bite malocclusions in growing patients.

The treatment of the hyperdivergent phenotype and/or anterior openbite is one of the common problems facing orthodontists. The purpose of this study is to present a new appliance (Molar Intruder) for molar intrusion and to determine its effects in the treatment of anterior openbite. The study group comprised 14 patients (eight girls and six boys), with a mean age of 10 years and 7 months. All presented anterior open bite malocclusions between the second premolars. The study was carried out on lateral head films taken before (T1) and after (T2) molar intrusion. Periapical radiographs, study models, and standard photographs of all the patients were also obtained before and after molar intrusion. The paired sample t-test was used to determine the differences between the parameters. The average treatment time with the Molar Intruder was five months. The mean intrusion of maxillary and mandibular molars was 1.86 mm and 1.04 mm, respectively. Maxillary incisors extruded 0.54 mm with a labial tipping of 1.46 degrees and overbite increased by 4.00 mm. The mandibular plane angle was decreased by 1.57 degrees, and the anterior face height was decreased by 1.86 mm on average. The mandible showed a counterclockwise rotation, the chin moved forward, and the posterior facial height/anterior facial height ratio was increased. Anterior openbites of the patients were significantly rehabilitated at the end of the intrusion period, simplifying further orthodontic treatment.

Cephalometry↗

Effects of PGI2 and TxA2 analogs and inhibitors in orthodontic tooth movement.

This study evaluates the effects of prostacyclin (PGI2) and thromboxane A2 (TxA2) in orthodontic tooth movement and osteoclastic activity in rats. The study sample consisted of 150 male Sprague-Dawley rats. The rats were randomly divided into five equal groups, and each group was again equally divided into three subgroups (SGs). Twenty grams of reciprocal force was applied to maxillary incisors of the rats with a spring bent from 0.35 mm stainless steel wire, except for the rats in the last SG. Iloprost (PGI2 analog), indomethacin (PGI2 inhibitor), U 46619 (TxA2 analog), and imidazole (TxA2 inhibitor) were dissolved in 0.9% NaCl (saline solution), and each material was prepared in three different concentrations (10(-4), 10(-5), and 10(-6) M/L). Iloprost was administered (20 microL/12 hours) in the first three SGs with the sequence of 10(-4), 10(-5), and 10(-6) M/L. Indomethacin, U 46619, and imidazole were administered in the next nine SGs with the same sequence and dose. In SG 13, 0.9% NaCl solution was administered (20 microL/ 12 hours) to the rats together with orthodontic force. Only orthodontic force was not used in SG 14, and neither any solution nor orthodontic force was used in the last SG. The rats were sacrificed on the fifth day of the experiment, premaxillae were dissected, and cross samples were taken. The results showed that PGI2 and TxA2 analogs increased the number of multinuclear osteoclasts, osteoclastic bone resorption, and rate of orthodontic tooth movement.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗