Fırat Öztürk

Real-time cell analysis of the cytotoxicity of orthodontic mini-implants on human gingival fibroblasts and mouse osteoblasts

INTRODUCTION The aim of this study was to evaluate the cytotoxic effects of orthodontic mini-implants on gingival fibroblasts and osteoblasts. METHODS The orthodontic mini-implants used in this study were Orthodontic Mini Implant (Leone, Florence, Italy), MTN (MTN, Istanbul, Turkey), AbsoAnchor (Dentos, Daegu, South Korea), IMTEC Ortho (3M Unitek, IMTEC, Ardmore, Okla), VectorTAS (Ormco, Glendora, Calif). The materials were incubated in Dulbeccos modified eagles culture medium 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). A real-time cell analyzer (xCELLigence, Roche Applied Science, Mannheim, Germany; ACEA Biosciences, San Diego, Calif) was used to evaluate cell survival. After seeding 200 μL of the cell suspensions into the wells of the E-plate 96, gingival fibroblasts were treated with bioactive components released by the metallic materials and monitored every 15 minutes for 190 hours. For the proliferation experiments, the statistical analyses used were 1-way analysis of variance and Tukey-Kramer multiple comparisons tests. RESULTS There was no significant differences between the human gingival fibroblast cell indexes of the control and study groups (P >0.05). When evaluated at 27 and 96 hours, only the VectorTAS mini-implants showed statistically significant decreases in the M3T3 cell index (P <0.001) compared with the control group. No significant differences were found among the control and all study groups (P >0.05). Furthermore, the Leone and MTN mini-implants showed statistically significant decreases (P <0.001) at 190 hours. Also, the VectorTAS mini-implants demonstrated a significant decline (P <0.05) at the same time in the M3T3 cell index. CONCLUSIONS These findings provide fundamental knowledge and new insights for future design and development of new biocompatible titanium alloys for orthodontic mini-implants and temporary anchorage devices.

Real-time cell analysis of the cytotoxicity of the components of orthodontic acrylic materials on gingival fibroblasts

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 Dulbeccos modified eagles 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 Dulbeccos 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.

The Relationship of Orthodontic Treatment Need with Periodontal Status, Dental Caries, and Sociodemographic Factors

The aim of this study was to determine the relationship of orthodontic malocclusion with periodontal status, dental caries, and sociodemographic status. Our study population consisted of a sample of 836 school children (384 male and 452 female, aged 11–14 years). Four experienced orthodontists and two experienced periodontists performed the clinical examinations. The Treatment Priority Index (TPI), Community Periodontal Index of Treatment Needs (CPITN), decayed, missing, filled teeth (DMFT) scores, and a questionnaire that surveyed socio-demographic status of students were used. Spearmans rank correlation coefficients were used to measure the association between variables. TPI scores showed that 36.4% of the students had normal occlusion, while 41.2% had slight, 15.7% had definite, 4% had severe, and 2.7% had very severe malocclusion. TPI values did not show any significant differences between pupils in different age, gender, socioeconomic status groups, and CPITN scores, whereas there was a significant relationship between TPI and DMFT scores. The orthodontic treatment need was not significantly correlated with CPITN or socio-demographic status; however, the correlation coefficient showed a significant relationship between TPI and DMFT scores.

Effects of zoledronic acid on sutural bone formation: a computed tomography study

The aim of this study was to investigate the effects of systemically applied zoledronic acid (ZA) on osteoblastic bone formation and relapse in the rat sagittal suture after expansion. Eighteen 12-week-old male Wistar rats were divided into three groups. In groups 1 and 2, a saline solution was given subcutaneously after expansion and the retention period lasted for 14 and 7 days, respectively. In group 3, 0.1 mg of ZA was diluted with saline and given subcutaneously after expansion: the retention period lasted for 7 days. Computed tomography (CT) measurements were obtained at the start of the study (T1), after expansion (T2), after the retention period (T3), and after the follow-up period (T4). The amount of expansion and relapse and the density of the newly formed bone in the expansion area were measured. The mean bone density values in hounsfield unit (HU) of the newly formed bone were recorded using MX View Workstation. Data were analysed using the Kruskal-Wallis, Friedman, Wilcoxon, and Mann-Whitney U-tests. The results showed that there were significant differences between the groups in the density of newly formed bone after the retention period (P < 0.05). Statistically significant differences were observed when the relapse percentages were compared between the groups (P < 0.05). ZA stimulated bone formation and decreased the relapse ratio after expansion in the rat sagittal suture.

Antibacterial and mechanical properties of propolis added to glass ionomer cement.

OBJECTIVE To investigate whether adding ethanolic extracts of propolis (EEP) might influence the antibacterial and mechanical (shear-peel band strength [SPBS]) properties of conventional glass ionomer cement (GIC) used in orthodontic band cementation. MATERIALS AND METHODS The cement was divided into four groups: one using the original composition and three with 10%, 25%, and 50% EEP added to the liquid and then manipulated. An antimicrobial assay, broth-dilution method was used to determine the antibacterial capacity of the GIC containing EEP. Eighty teeth were used for the mechanical assay, and an Instron testing machine was used to evaluate the SPBS. Kolmogorov-Smirnov and Kruskal-Wallis tests were used for statistical analyses. RESULTS GIC with the addition of 25% and 50% EEP activated inhibition of Streptococcus mutans (ATCC 25175) growth, but this effect did not occur in the group to which 10% EEP was added or in the control GIC group. There was no significant difference between the groups in terms of SPBS (P > .05). CONCLUSIONS The addition of EEP may increase antibacterial properties without negatively modifying the mechanical properties of conventional GIC.

Identical unerupted maxillary incisors in monozygotic twins.

Mesiodens is the most common type of supernumerary tooth found in the premaxilla. It might be discovered by the orthodontist by chance on a radiograph or as the cause of an unerupted maxillary central incisor. The genetic transmission of supernumerary and impacted teeth is poorly understood. The occurrence of identical unerupted maxillary central incisors and mesiodentes in monozygotic twins suggests that genetic factors might influence the etiology of this problem. In this case report, we discuss the treatment of unerupted maxillary permanent incisors caused by mesiodentes in monozygotic twins.

Oral and Nasal Malodor In Patients With and Without Cleft Lip and Palate Who Had Undergone Orthodontic Therapy

Objective: To compare oral and nasal malodor in patients with and without cleft lip and palate (CLP) who had undergone orthodontic therapy. Setting: University of Cumhuriyet, Sivas, Turkey. Patients: The study included 33 patients. Group 1 was composed of 11 patients with CLP. Measurements were taken while they were undergoing treatment with orthodontic fixed appliances. Group 2 included 11 individuals without CLP; measurements were taken during fixed orthodontic therapy. Group 3 consisted of 11 individuals without CLP who did not receive orthodontic therapy. Intervention: Oral malodor, nasal malodor, Gingival Index, Plaque Index, and probing depths were evaluated in each group. Results: Plaque Index, Gingival Index, and probing depths showed no significant differences between groups 1 and 2. In contrast, oral malodor was significantly different between the two groups (p < .05). Groups 2 and 3 showed differences in gingival and plaque indices but not in probing depths and oral malodor. All healthy nostrils in Group 1, Group 2, and Group 3 were significantly different from affected nostrils in the CLP patients. There was significant malodor in affected nostrils when compared with nonaffected nostrils in group 1 (p < .05). Conclusion: Oral malodor was increased in patients with CLP. Nasal malodor level was also higher in affected nostrils of the CLP patients compared to nostrils of healthy subjects.

Level of residual monomer released from orthodontic acrylic materials

OBJECTIVE To quantify, with high-pressure liquid chromatography (HPLC), the amount of residual monomer leached from different orthodontic acrylic materials prepared with two different manipulation methods. MATERIALS AND METHODS Eighty cylindrical specimens (5 × 25 mm) were divided into eight groups (n  =  10). The specimens were prepared with four acrylic materials-Orthocryl Neon Blue (Dentaurum), Orthocryl EQ (Dentaurum), Orthoplast (Vertex), and O-80 (Imicryl)-and with two different manipulation methods: doughing and spray-on. HPLC measurements were made at intervals of 2 hours, 6 hours, 1 day, 1 week, and 3 months. One-way analysis of variance (ANOVA) and Tukeys honestly significant difference multiple-comparison test were used to assess the amount of monomer eluted from the various groups. To assess the differences within each group over the various periods, repeated-measures ANOVA and paired t-tests were used. RESULTS Statistically significant differences were found within the groups in the amount of residual monomer in the specimens at different time intervals (P < .001). HPLC showed statistically significant differences among the groups (P < .05) in the amount of eluted monomer. Evaluation of the manipulation techniques showed that the monomer release rate was higher in the specimens prepared with the doughing method. When the four acrylic materials were compared, the specimens made from Orthoplast (Vertex) showed the highest rate of monomer release with both manipulation techniques. CONCLUSION The spray-on method can be recommended to clinicians for the preparation of orthodontic appliances.

Comparison of Bolton analysis and tooth size measurements obtained using conventional and three-dimensional orthodontic models.

Objectives: The aim of this study was to compare the accuracy, reproducibility, efficacy and effectiveness of measurements obtained using digital models with those obtained using plaster models. Materials and Methods: A total of 20 digital models were produced by the Ortho Three-dimensional Models (O3DM) Laboratory and their software (O3DM version 2) was used to obtain measurements. Identical plaster models were used to obtain measurements of teeth with a vernier caliper. The maximum mesiodistal width of each study model, from first molar to first molar, was measured. All measurements were repeated at least 1 month later by the same operator for both digital and manual methods. The data were analyzed using Cronbach α, Wilcoxon signed rank test and the McNemar test. Results: Cronbach α value of the data at T1 and T2 for 6 anterior and 12 overall teeth measured using the two methods was very close to the ideal value of 1, indicating high intra-observer reliability. The Wilcoxon signed rank test showed statistically significant differences between the two methods (P = 0.000, P < 0.001). The measurements obtained using the digital models were lower than those obtained using the plaster models. No statistically significant differences were found between the two methods for anterior Bolton discrepancies (P = 0.375) or overall Bolton discrepancies (P = 0.00). Paired comparisons of repeated measurements for Bolton ratios showed no statistically significant differences for anterior or overall Bolton discrepancies (P = 0.688 and P = 0.375, respectively). Conclusions: Use of O3DM software is an acceptable alternative to the traditional vernier caliper method in orthodontic practice.

Real-time cell analysis of cytotoxicity of orthodontic cements on gingival fibroblasts

Introduction: To evaluate the cytotoxicity of four different orthodontic cement materials using the real-time xCELLigence system. Materials and Methods: Four orthodontic glass ionomer cements (GICs) were selected for this study, namely: GC Fuji (GC Cooperation), Ultra Band Lok (Reliance), Multi Cure (3M Unitek), and Meron (Voco). Ten test cylinders (measuring 5 Χ 2 mm) of each material were fabricated, making a total of 40 cylinders. The samples were incubated in Dulbecco modified Eagle medium (DMEM) culture medium for 72 hours. Human gingival fibroblasts (HGFs) were maintained with DMEM containing 10% fetal bovine serum. A real-time cell analyzer (RT-CES, xCELLigence) was used to evaluate cell survival. After seeding 200 μL of the cell suspensions into the wells (10,000 cells/well), gingival fibroblasts were treated with bioactive components released from cement materials and were monitored every 15 minutes for a period of 88 hours. For proliferation experiments, the statistical analyses used were one-way analysis of variance (ANOVA) and Tukey-Kramer multiple comparisons tests. Results: When the data were evaluated at 24 and 48 hrs, all tested materials showed statistically significant decreases in HGF cell index compared to the control group (P < 0.001). Conclusion: According to the results of this study, all tested cements were found to have cytotoxic effects to the HGFs.