Fulya Ozdemir

Reduction of salivary mutans streptococci in orthodontic patients during daily consumption of yoghurt containing probiotic bacteria

Previous studies have suggested that probiotic supplements in dairy products may affect the oral microbial ecology, but the effect in orthodontic patients has not previously been reported. The aim of the present study was to examine whether short-term consumption of fruit yogurt containing probiotic bifidobacteria would affect the levels of salivary mutans streptococci and lactobacilli in patients with fixed orthodontic appliances. A double-blind, randomized crossover study was performed and 24 healthy adolescents (12-16 years) undergoing orthodontic treatment were followed over four periods. During periods 2 and 4 (2 weeks each), the subjects ingested 200 g fruit yogurt containing Bifidobacterium animalis subsp. lactis DN-173010 (2 x 10(8) colony forming units/g) once daily or a control yogurt without viable bacteria. Periods 1 and 3 were run-in and wash-out periods of 1 and 6 weeks, respectively. Salivary mutans streptococci and lactobacilli were enumerated with chair-side kits before and after the yogurt consumption periods. Pre- and post-treatment values within each regimen were compared with a two-tailed marginal homogeneity test for categorical data. A statistically significant reduction of salivary mutans streptococci was recorded after probiotic yogurt consumption (P < 0.05), which was in contrast to the control yogurt. No significant alterations of the salivary lactobacilli counts were observed. Short-term daily consumption of fruit yogurt containing Bifidobacterium animalis subsp. lactis DN-173010 may reduce the levels of mutans streptococci in saliva during orthodontic treatment with fixed appliances.

Cortical bone thickness of the alveolar process measured with cone-beam computed tomography in patients with different facial types.

INTRODUCTION The purpose of this study was to determine the cortical bone thickness of the alveolar process in the maxilla and the mandible on cone-beam computed tomographs of adults with low, normal, and increased facial heights. METHODS This study was conducted on 155 images of adult patients (20-45 years old) who were assigned to the low-angle, normal, and high-angle groups. The thickness of the buccal cortical plates of the maxilla and the mandible, and the palatal cortical plates of the maxilla, were measured. RESULTS There was no statistically significant difference between the groups regarding mean ages, sex, and sagittal facial types. High-angle patients had significantly lower values than did low-angle patients in all mini-implant insertion sites in both the maxillary and mandibular alveolar bones. The mandibular and maxillary buccal measurements showed a similar pattern; the lowest values were for the high-angle group, followed by the normal group; the highest values were measured in the low-angle patients. CONCLUSIONS Clinicians should be aware of the probability of thin cortical bone plates and the risk of mini-implant failures at maxillary buccal alveolar mini-implant sites in high-angle patients, and at mandibular buccal alveolar mini-implant sites between the canine and the first premolar in normal and high-angle patients.

Quantitative evaluation of alveolar cortical bone density in adults with different vertical facial types using cone-beam computed tomography

Objective The purpose of this study was to quantitatively evaluate the cortical bone densities of the maxillary and mandibular alveolar processes in adults with different vertical facial types using cone-beam computed tomography (CBCT) images. Methods CBCT images (n = 142) of adult patients (20-45 years) were classified into hypodivergent, normodivergent, and hyperdivergent groups on the basis of linear and angular S-N/Go-Me measurements. The cortical bone densities (in Hounsfield units) at maxillary and mandibular interdental sites from the distal aspect of the canine to the mesial aspect of the second molar were measured on the images. Results On the maxillary buccal side, female subjects in the hyperdivergent group showed significantly decreased bone density, while in the posterior region, male subjects in the hyperdivergent group displayed significantly decreased bone density when compared with corresponding subjects in the other groups (p<0.001). Furthermore, the subjects in the hyperdivergent group had significantly lower bone densities on the mandibular buccal side than hypodivergent subjects. The maxillary palatal bone density did not differ significantly among groups, but female subjects showed significantly denser palatal cortical bone. No significant difference in bone density was found between the palatal and buccal sides in the maxillary premolar region. Overall, the palatal cortical bone was denser anteriorly and buccal cortical bone was denser posteriorly. Conclusion Adults with the hyperdivergent facial type tend to have less-dense buccal cortical bone in the maxillary and mandibular alveolar processes. Clinicians should be aware of the variability of cortical bone densities at mini-implant placement sites.

Orthodontic bonding to acid- or laser-etched prebleached enamel

Objective Bonding forces of brackets to enamel surfaces may be affected by the procedures used for bleaching and enamel etching. The aim of this study was to investigate the bonding strength of orthodontic brackets to laser-etched surfaces of bleached teeth. Methods In a nonbleached control group, acid etching (group A) or Er:YAG laser application (group B) was performed prior to bracket bonding (n = 13 in each group). Similar surface treatments were performed at 1 day (groups C and D; n = 13 in each subgroup) or at 3 weeks (groups E and F; n = 13 in each subgroup) after 38% hydrogen peroxide bleaching in another set of teeth. The specimens were debonded after thermocycling. Results Laser etching of bleached teeth resulted in clinically unacceptable low bonding strength. In the case of acid-etched teeth, waiting for 3 weeks before attachment of brackets to the bleached surfaces resulted in similar, but not identical, bond strength values as those obtained with nonbleached surfaces. However, in the laser-etched groups, the bonding strength after 3 weeks was the same as that for the nonbleached group. Conclusions When teeth bleached with 38% hydrogen peroxide are meant to be bonded immediately, acid etching is preferable.

Shear bond strength of brackets bonded to amalgam with different intermediate resins and adhesives

The aims of this study were to compare, in vitro, the shear bond strength (SBS) of stainless steel orthodontic brackets bonded to silver amalgam with the use of three different intermediate resins and two different adhesives, and to evaluate bond failure mode. Forty-five amalgam specimens were divided into three equal groups. In groups 1 and 2, the brackets were bonded with Unite (3M Unitek) using Reliance Metal Primer (RMP; Reliance Orthodontic Products) and Power Bond OLC (PB OLC; Ortho Organizers Inc.) as intermediate resins, respectively. In group 3, Resinomer and One-Step Plus (OS+; Bisco Inc.) were used. Thirty bovine teeth served as the controls to test bracket bonding to acid-etched enamel with Unite and Resinomer-OS+. After thermocycling from 10 to 50 degrees C 1000 times, all samples were tested for SBS. Bond failure sites were classified using a modified adhesive remnant index (ARI) system. Data were analyzed with one-way analysis of variance, post hoc Tukey multiple comparison and chi-square tests. The results showed that the mean SBS to amalgam surfaces were significantly lower than those to etched bovine enamel (P<0.001). There were no statistically significant differences in mean SBS between the amalgam bonding groups (P>0.05). For the ARI, significant differences were found between the amalgam- and enamel-bonding groups (P<0.001). The mean SBS of stainless steel orthodontic brackets bonded to amalgam surfaces with RMP, PB OLC, OS+ intermediate resins and Unite and Resinomer adhesives was significantly lower than to etched bovine enamel. Bond failure occurred at the amalgam-adhesive interface regardless of the adhesive system and without damage to the amalgam restoration.

Effects of fixed functional therapy on tongue and hyoid positions and posterior airway

OBJECTIVE To evaluate how therapy with a fixed functional appliance affects airway dimensions, dentoalveolar changes, and tongue and hyoid positions. MATERIALS AND METHODS A retrospective study was carried out on 46 pre- and posttreatment lateral cephalometric radiographs of 23 post-peak Class II patients (12 girls, 11 boys) treated with a Forsus Fatigue Resistant Device (FRD) appliance. The radiographies were taken at the start and at the end of Forsus FRD appliance therapy when a Class I or overcorrected Class I canine and molar relationship was achieved. The process took an average of 5 months 13 days ± 1 month 4 days. Skeletal and dental parameters were measured using Dolphin software, and the sagittal airway area was measured by AutoCAD software. RESULTS Analyses of the pre- and posttreatment means revealed that there was no statistically significant skeletal correction of the sagittal malocclusion; increase of lower incisor inclination, decrease of upper incisor inclination, decrease of interincisal angle, and rotation of occlusal plane all contributed to the reduction of overjet. The tongue area and intermaxillary space area increased in response to these dentoalveolar changes; however, there was no statistically significant change in the hyoid position or the oropharyngeal area between the two time points. CONCLUSIONS The dentoalveolar changes produced by Forsus FRD appliance did not cause any significant posterior airway changes in young adult patients.

The effects of three different mouth rinses in a 4-day supragingival plaque regrowth study

Objective: This study compares the effects of three different mouth rinses with respect to reducing Streptococcus mutans (S. mutans) colony counts on the teeth and tongue surfaces. Materials and Methods: In this study, comparison tests using the alcohol-free 0.1% chlorhexidine mouth rinse, alcohol-containing essential oil mouth rinse, and alcohol-free essential oil-containing mouth rinse were conducted. Patients were instructed to avoid mechanical cleaning with either a toothbrush or toothpick for 4 days. The first samples were collected from teeth surfaces and the dorsum of the tongue after a professional cleaning, and the second samples were collected after a 4-day plaque re-growth period. The supragingival plaque from the buccal surfaces of teeth #11, 14, 31, 34 as well as samples from the dorsum of the tongue, were assessed using the Dentocult® strips. Results: The Listerine® and Ondrohexidine® groups did not show any statistically significant differences between the values of the two samples (P = 0.734, P = 0.307). The MC® group and the control group showed significantly higher results than the first sample values. The effectiveness of the mouth rinses on S. mutans colony counts from the teeth surfaces were higher in the Listerine® , Ondrohexidine® , and Mouthwash Concentrate® groups. The difference between the first and second samples of the S. mutans colony counts from the tongue surface was found to be statistically significant, and S. mutans colony counts were higher than the first sample (P = 0.015). Conclusion: Alcohol and essential oil-containing Listerine® mouth rinse, alcohol-free Ondrohexidine® , alcohol-free essential oil-containing MC® mouth rinse had the same effect on S. mutans counts, higher than the 1% alcohol solution on teeth surface. They had the ability to maintain the S. mutans counts at the same level for 4 days in patients who did not perform any mechanical oral hygiene regimen.

Effects of a newly designed apparatus on orthodontic skeletal anchorage

Objective: An appliance was designed to increase the cortical bone surface contact area of miniscrew implants (MSIs). The purpose of this in vitro study was to evaluate the effects of this appliance on the anchorage force resistance and the stability of orthodontic MSIs. Materials and Methods: A total of 48 MSIs were placed into bone specimens prepared from the ilium of bovines. Half were placed with the newly designed apparatus and half were placed conventionally. All the specimens were subjected to tangential force loading perpendicular to the MSI with lateral displacement of 0.6 mm, using an Instron Universal Testing machine. The maximum removal torque of each tested specimen was also recorded. Both study and control groups were divided into two subgroups based on whether they had thin and thick cortical bone. Results: The test group had statistically higher force anchorage resistance and maximum insertion torque values than the control group (P < 0.001). The results were found to be more significant in cases in which the cortical bone was thin (P < 0.001). Conclusions: Within the limits of this in vitro study, the present findings suggest that the newly designed apparatus might have a favorable effect on MSI stability in patients presenting with thin cortical bone. Clinical studies are necessary to confirm the results that were observed in vitro.

Maxillary buccal cortical plate inclination at mini-screw insertion sites

OBJECTIVE To evaluate whether buccal cortical bone inclination varies for the maxillary alveolar processes of adult patients with decreased, normal, and increased facial heights. MATERIALS AND METHODS Cone-beam computed tomography images of 135 adult patients, including 49 hypodivergent subjects (26 women, 23 men), 40 hyperdivergent subjects (24 women, 16 men), and 46 normodivergent (25 women, 21 men) were analyzed. Cortical bone inclination measurements were made relative to the occlusal plane. Cross-sectional slices of the maxilla were taken at interdental sites from the distal aspect of maxillary canine to the mesial aspect of maxillary second molar. RESULTS Analysis of variance indicated significant differences (P < .05) between the angles formed by the line tangent to the cortical bone and the occlusal plane among the vertical facial types for the regions between canine and first premolar and between second premolar and first molar at miniscrew insertion sites. CONCLUSION The results of this study indicate that vertical facial pattern should be taken into consideration when adjusting the insertion angle of miniscrews at the maxillary buccal region.

Mini-İmplantların Devrilmesini Önlemede Yeni Bir Yaklaşım

OZET Amac: Calismanin amaci, ortodontik yuk altinda mini-implant deplasman miktarini belirlemek ve mini-implantlarin yaka kismina yerlestirilen yeni tasarlanmis bir aparatin (mini-implant ring - MIR) etkinligini degerlenmektir. Gerecler ve Yontem: Toplam 48 mini-implant sigir kalca kemiginden elde edilen orneklere uygulanmistir. Calisma grubunda 24 mini-implant MIR ile uygulanmis ve kalan mini-implantlar MIR olmadan uygulanarak kontrol olarak ayrilmistir. Tum mini-implantlar vida uzun eksenine dik olacak sekilde 200 g teget yuke tabi tutulmuslar ve vidalarin yer degistirmesi Instron Universal Test Makinesi kullanilarak milimetre cinsinden olculmustur. Yukleme testi sonrasi, her bir mini-implant cikarilmis ve kortikal kemik orneklerinin kalinliklari olculmustur. Orneklerin kortikal kalinligina gore, calisma ve kontrol gruplari, ince ve kalin kortikal kemik olarak alt gruplara ayrilmistir. Bulgular: 200 g kuvvet uygulandiginda, MIR ile uygulanan mini-implantlarin ortalama deplasman degerleri MIR olmadan uyg...