Abdullah Ekizer

Resonance frequency analysis of orthodontic miniscrews subjected to light-emitting diode photobiomodulation therapy.

The aim of this prospective experimental study was to evaluate the effect of light-emitting diode (LED) photobiomodulation therapy (LPT) on the stability of immediately loaded miniscrews under different force levels, as assessed by resonance frequency analysis (RFA). Sixty titanium orthodontic miniscrews with a length of 8 mm and a diameter of 1.4 mm were implanted into cortical bone by closed flap technique in each proximal tibia of 15 New Zealand white adult male rabbits (n = 30). The animals were randomly divided into irradiated and control groups under different force levels (0, 150, and 300 cN). OsseoPulse® LED device (Biolux Research Ltd.) 618 nm wavelength and 20 mW/cm(2) output power irradiation (20 minutes/day) was applied to the miniscrews for 10 days. The RFA records were performed at miniscrew insertion session (T1) and 21 days after surgery (T2). Wilcoxon and Mann-Whitney U-tests were used for statistical evaluation at P < 0.005 level. It was found that initial primer stability of all miniscrews was similar in all groups at the start of the experimental procedure. Statistically significant differences were found for changes in implant stability quotient (ISQ) values between LED-photobiomodulated group and the control (0 cN, P = 0.001; 150 cN, P < 0.001; and 300 cN, P < 0.001). Significant increase was found in ISQ values of LPT applied miniscrews under 0 cN (+11.63 ISQ), 150 cN (+10.50 ISQ), and 300 cN (+7.00 ISQ) force during observation period. By the increase of force levels, it was determined that ISQ values decreased in non-irradiated control miniscrews. Within the limits of this in vivo study, the present RFA findings suggest that LPT might have a favourable effect on healing and attachment of titanium orthodontic miniscrews.

Effects of demineralizaton-inhibition procedures on the bond strength of brackets bonded to demineralized enamel surface

Objective To study and compare the effects of different demineralization-inhibition methods on the shear bond strength (SBS) and fracture mode of an adhesive used to bond orthodontic brackets to demineralized enamel surfaces. Methods Eighty freshly extracted, human maxillary premolars were divided into 4 equal groups and demineralized over the course of 21 days. Brackets were bonded to the demineralized enamel of teeth in Group 1. In Group 2, bonding was performed following resin infiltration (ICON®, DMG, Hamburg, Germany). Before bonding, pre-treatment with acidulated phosphate fluoride (APF) or solutions containing casein phosphopeptide-amorphous calcium phosphate with 2% neutral sodium fluoride (CPP-ACP/wF) was performed in Groups 3 and 4, respectively. The SBS values of the brackets were measured and recorded following mechanical shearing of the bracket from the tooth surface. The adhesive remnant index (ARI) scores were determined after the brackets failed. Statistical comparisons were performed using one-way ANOVA, Tukeys post-tests, and G-tests. Results Significant differences were found in some of the intergroup comparisons of the SBS values (F = 39.287, p < 0.001). No significant differences were found between the values for the APF-gel and control groups, whereas significantly higher SBS values were recorded for the resin-infiltrated and CPP-ACP/wF-treated groups. The ARI scores were also significantly different among the 4 groups (p < 0.001). Conclusions Tooth surfaces exposed to resin infiltration and CPP-ACP/wF application showed higher debonding forces than the untreated, demineralized surfaces.

Treatment effects of skeletally anchored Forsus FRD EZ and Herbst appliances: A retrospective clinical study.

OBJECTIVE To evaluate the skeletal, dentoalveolar, and soft tissue effects of the Forsus FRD appliance with miniplate anchorage inserted in the mandibular symphyses and to compare the findings with a well-matched control group treated with a Herbst appliance for the correction of a skeletal Class II malocclusion due to mandibular retrusion. MATERIALS AND METHODS The sample consisted of 32 Class II subjects divided into two groups. Group I consisted of 16 patients (10 females and 6 males; mean age, 13.20 ± 1.33 years) treated using the Forsus FRD EZ appliance with miniplate anchorage inserted in the mandibular symphyses. Group II consisted of 16 patients (9 females and 7 males; mean age, 13.56 ± 1.27 years) treated using the Herbst appliance. Seventeen linear and 10 angular measurements were performed to evaluate and compare the skeletal, dentoalveolar, and soft tissue effects of the appliances using paired and Students t-tests. RESULTS Both appliances were effective in correcting skeletal class II malocclusion and showed similar skeletal and soft tissue changes. The maxillary incisor was statistically significantly more retruded in the skeletally anchored Forsus FRD group (P < .01). The mandibular incisor was retruded in the skeletally anchored Forsus FRD group (-4.09° ± 5.12°), while it was protruded in the Herbst group (7.50° ± 3.98°) (P < .001). CONCLUSION Although both appliances were successful in correcting the skeletal Class II malocclusion, the skeletally anchored Forsus FRD EZ appliance did so without protruding the mandibular incisors.

Bone marrow mesenchymal stem cells enhance bone formation in orthodontically expanded maxillae in rats.

OBJECTIVE To transplant bone marrow-derived mesenchymal stem cells (MSCs) into the interpremaxillary suture after rapid maxillary expansion with the aim of increasing new bone formation in the suture. MATERIALS AND METHODS Nineteen male Wistar rats were divided into two groups (control, n  =  9; experimental, n  =  10). Both groups were subjected to expansion for 5 days, and 50 cN of force was applied to the maxillary incisors with a helical spring. Pkh67(+) (green fluorescent dye)-labeled MSCs were applied to the interpremaxillary suture after force application into the interpremaxillary suture of rats. Bone formation in the sutural area was histomorphometrically evaluated, including the amount of new bone formation (µm(2)), number of osteoblasts, number of osteoclasts, and number of vessels. Mann-Whitney U-test was used for statistical evaluation at the P < .05 level. RESULTS After 10 days of retention, Pkh67(+) can be detected in suture mostly in the injection site under fluorescence microscope. Histomorphometric analysis revealed that a single local injection of MSCs into the midpalatal suture increased the new bone formation in the suture by increasing the number of osteoblasts and new vessel formation, compared with controls injected with phosphate-buffered saline. CONCLUSIONS This preclinical study might provide foundations for the underlying potential clinical use of MSCs after maxillary expansion. Given the fact that MSCs are currently in use in clinical trials, this approach might be a feasible treatment strategy to accelerate new bone tissue formation in midpalatal suture and to shorten the treatment period for patients undergoing maxillary expansion reinforcement.

A survey of ponticulus posticus: Radiological analysis of atlas in an orthodontic population based on cone-beam computed tomography.

Background: The ponticulus posticus (PP; Latin for little posterior bridge) has become an important anomaly of the atlas, as the use of the C1 lateral mass screw has become common in treating atlantoaxial instability. Aim: The purpose of this study was to retrospectively determine the prevalence and morphologic characteristics of PP in an orthodontic patient population using cervical three-dimensional (3-D) cone beam computed tomography (CBCT) images. Material and Methods: A retrospective study was conducted by selecting cervical 3-D CBCT images of 374 adolescent population and examining them for the presence and type of PP. Results: 161 patients with 298 complete or partial or bilateral or unilateral PPs were identified based on the 374 cervical 3-D CBCT scans. The prevalence of posticulus ponticus was founded 43.04% in adolescent population. Conclusion: Our results show that the presence of this anomaly should be carefully examined using preoperative lateral radiographs before lateral mass screw placement. If a PP is suspected or confirmed on radiographs, 3-D CBCT scanning should be considered before lateral mass screw placement into the posterior arch because of the variation in the size and shape of PPs and the possibility of injury.

Light emitting diode mediated photobiomodulation therapy improves orthodontic tooth movement and miniscrew stability: A randomized controlled clinical trial

The aim of this study was to evaluate the effects of light‐emitting diode‐mediated‐photobiomodulation therapy (LPT) on the stability of miniscrews, rate of orthodontic tooth movement, and interleukin‐1β levels in gingival and peri‐implant crevicular fluid.

Evaluation of mandibular transverse widths in patients affected by unilateral and bilateral cleft lip and palate using cone beam computed tomography

OBJECTIVE To evaluate the mandibular dental, alveolar, and skeletal transversal widths in patients affected by unilateral (UCLP) and bilateral (BCLP) cleft lip and palate and to compare the findings with a well-matched normal occlusion sample using cone beam computed tomography images. MATERIALS AND METHODS The study sample consisted of 75 patients divided into three groups: the UCLP (29 patients; mean age: 15.40 ± 3.22 years), BCLP (18 patients; mean age: 15.54 ± 3.72 years), and normal occlusion (28 patients; mean age: 15.82 ± 2.11 years) groups. Mandibular dental (intercanine and -molar), alveolar (intercanine and -molar), and skeletal (bigonial width) transversal measurements were performed three-dimensionally and analyzed using the one-way variance analysis and post hoc Tukey tests. RESULTS Patients affected by UCLP and BCLP had statistically significantly lower intercanine alveolar widths (P < .05 and P < .001, respectively) and larger intermolar (P < .001 and P < .05, respectively) and intermolar alveolar widths (P < .001) compared with the normal occlusion group. Furthermore, the patients affected by UCLP and BCLP had similar mandibular dental, alveolar, and skeletal transversal widths (P > .05). CONCLUSION The UCLP and BCLP groups showed statistically significantly smaller values for intercanine alveolar widths and larger values for intermolar dental and alveolar widths compared with the normal occlusion group. This shows the importance of using individualized archwires according to the pretreatment arch widths of the patients affected by UCLP and/or BCLP.

Re: Response to: Bone marrow mesenchymal stem cells enhance bone formation in orthodontically expanded maxillae in rats. Abdullah Ekizer, Mehmet Emir Yalvac, Tancan Uysal, Mehmet Fatih Sonmez, Fikrettin Sahin. The Angle Orthodontist. Online Early

Thank you for the comments made on our paper. We believe that this study is a novel proof of principle study and it suggests potential use of mesenchymal stem cells (MSCs) after maxillary expansion. Based on this report, we and other groups can work on improving the technique and testing the efficacy of MSCs in reducing relapse rates compared to the other options. We apologize for the mistake in our reported Results and have made corrections in the text and in Table 2:

The effect of isoflavones on early bone formation on orthopedically expanded suture in male rats

Objective: The aim of this experimental study was to evaluate histomorphometrically the effects of isoflavones on bone formation in response to expansion of the inter-premaxillary suture in male rats. Materials and Methods: Twenty male, 50-60 days old Wistar rats were divided into two equal groups (control and experimental). Both groups were subjected to expansion for 5 days, and 50 cN of force was applied to the maxillary incisors with helical spring. In experimental group, 10 μg/g isoflavones (IF) were administrated orally. After expansion period, the springs were removed and replaced with short lengths of rectangular retaining wire for retention period in 10 days. Bone formation in the sutural area was histomorphometrically evaluated including the amount of new bone formation (μm 2 ), number of osteoblasts, number of osteoclasts, and number of vessels. Mann-Whitney U -test was used for statistical evaluation at P Results: New bone formation area ( P = 0.003; 2.26-fold) and number of osteoclasts ( P = 0.001; 1.87-fold) showed statistically significant lower values in experimental group than the control. No significant differences were found in number of osteoblast and number of vessel values between the groups. Conclusion: Isoflavones affects bone formation in the orthopedically expanded inter-premaxillary suture negatively, and main affect of Isoflavones were on osteoclasts in bone metabolism.

Lingual Retainer Uygulamalarında Farklı Kompozitlerin Bağlanma Dayanımlarının Değerlendirilmesi

OZET Bu calismanin amaci farkli tip kompozitlerin, lingual retainer uygulamalarinda kullanildiklarinda baglanma dayanimlarinin ve kirilma tiplerinin degerlendirilmesidir Calismada altmis adet alt keser dis akrilik rezin bloklar icine dislerin kronlarinin bukkal yuzeyleri tabana paralel olacak sekilde yerlestirildi. Rastgele secilmis 20 dis iceren uc esit grup olusturuldu. Calismada uc farkli kompozit; Transbond-LR (3M-Unitek), Transbond-XT (3M-Unitek) ve Venus Flow (Heraeus Kulzer) test edildi. Lingual retainer yapistirilmasini taklit etmek icin materyaller dis uzerine 2,34 mm capi ve 3 mm yuksekligi olan silindirik plastik matrisler (Ultradent) kullanilarak uygulandi. Baglanma dayanimi testi icin ornekler Universal test makinesine yerlestirilerek kopma olana kadar her bir ornege, yuk bolmesine baglanan bir aparat (Ultradent) ile kompresyon kuvveti uygulandi. Baglanma dayaniminin degerlendirilmesinde Varyans analizi ve Tukey testi, kopma tipinin analizinde ki-kare testi kullanildi. Istatistiksel testler T...