Turkish Journal of Orthodontics最新文献

Objective: To evaluate the effect of emotional states on reproducibilities of rest position, social and spontaneous smiles, and speech.

Methods: A total of 30 individuals aged 18-22 years were included (mean age; 19.03 years ±1.03). Three emotional states were determined: amusing, sadness, and neutral. The participants watched three different videos in 3 sessions on the same day. After each video, the participants completed a questionnaire to assess their mood. The rest position, social and spontaneous smiles, and speech recordings were gathered from the participants using videographic method. Measurements were made for each function. The Friedman test, One-Way ANOVA, Kruskal-Wallis test was performed for statistical evaluations, and intra-observer correlation coefficients and Bland-Altman Limits of Agreement were calculated.

Results: In spontaneous smiles, there were significant differences between amusing and sadness in the smile height (p=0.020); amusing and sadness in the lower lip thickness (p=0.029). In social smiles there was a significant difference between amusing and sadness in the maxillary incisor display (p=0.006). There were no statistically significant differences in the rest position, but clinically significant differences were observed in some participants. In speech, a significant difference was found between amusing and sadness in the distance between the upper lip and subnasal (p=0.035).

Conclusion: The reproducibility of social and spontaneous smiles was influenced by various emotional states. However, the rest position exhibits higher reproducibility than social and spontaneous smiles in all emotional states.

Objective: This study aimed to compare the manufacturing accuracy of different printing techniques - Stereolithography (SLA), Digital Light Processing (DLP), and PolyJet-using digital dental models.

Methods: The study included cast models of 30 patients aged between 12 and 20 years. The selected models were scanned using an intraoral scanner, and surface topography format files were obtained. The models were produced from 3D printers with SLA, DLP, and PolyJet technology and scanned with an intraoral scanner. The digital files of the reference and printed models were superimposed with reverse engineering software. Root mean squared (RMS) values and point registration differences were evaluated. Furthermore, digital mesiodistal measurements of the teeth were taken to determine the point registration deviation values. Descriptive statistics were used to evaluate the measurements. ANOVA was used to evaluate differences between normally distributed data. In addition, a box plot was used to show the variability in the measurements, and the Bland-Altman test was used to examine the agreement between the measurements.

Results: According to the digital superimposition data of DLP-SLA-PolyJet technologies, PolyJet had the smallest RMS (0.145±0.10 mm), followed by DLP and SLA (0.161±0.12 mm and 0.345±0.23 mm, respectively). In the mesiodistal dimensional measurement evaluations, there was no statistically significant difference (p>0.05) between the averages of the main reference and DLP, PolyJet, and SLA measurements for all teeth.

Conclusion: According to the results of this study, all three production technologies are clinically usable at the model production stage. However, SLA was found to be less accurate than DLP and PolyJet.

Objective: The aim of this retrospective study was to compare the effects of the Twin block and Herbst appliances on the mandibular trabecular pattern using fractal dimension analysis (FDA) of panoramic radiographs (PRs).

Methods: The PRs of 50 subjects with skeletal Class II malocclusion who underwent the Twin block (T-group, average age: 11.63±0.87; 25 girls, 25 boys), 50 subjects with skeletal Class II malocclusion who underwent the Herbst (H-group, average age: 11.72±0.91; 27 girls, 23 boys), and 50 controls (C-group average age: 11.67±0.83; 24 girls, 26 boys) were selected. The condyle, corpus, and angulus regions of all groups in the mandible were examined using FDA.

Results: The condylar region (p≤0.001) and corpus mandible in the treatment groups (T-group: right, p≤0.05, left, p≤0.01; H-group: p≤0.05), as well as the left and right condylar region (p≤0.001) and left corpus mandible (p≤0.05) in the C-group, all indicated substantial increases in FDA between T0 and T1. Inter-group comparisons indicated that the T-group had greater variances in the condyle (p≤0.001) compared to the H group.

Conclusion: As the findings revealed both Twin block and Herbst appliances not only contributed to the dentoalveolar structure but also provided remodeling of the mandibular trabecular structure. Consequently, the null hypothesis was rejected.

Objective: The aim of this study was to evaluate and compare microleakage under the conventional and flash-free ceramic brackets bonded with different agents.

Methods: Forty extracted human maxillary premolar teeth were randomly divided into five groups. According to the groups, adhesive coated and conventional bracket systems were bonded to the tooth surfaces with the specified adhesive agents. To simulate a six-month oral environment, all teeth were subjected to a thermal cycle procedure. Micro-computed tomography (micro-CT) was used to view and measure the microleakage. Kruskal-Wallis test was used to compare the parameters and Mann-Whitney U test was used for the determination of the group that caused the difference. For intragroup comparisons Wilcoxon signed-rank test was used.

Results: Microleakage volume (mm³) and microleakage percentage (%) measured in Blugloo™ group was found significantly lower (p<0.05) then other groups. There was no significant difference in microleakage volume (mm³) and percentage (%) in comparison of gingival and occlusal regions (p>0.05).

Conclusion: Adhesive precoated flash-free brackets were not shown a significant difference compared to their conventional equivalent for microleakage volume. The brackets bonded with Blugloo™ adhesive were showed significant less microleakage than the other groups.

Objective: To investigate the effect of deferred timing of therapeutic extraction on the rate of space closure during en masse anterior retraction.

Methods: Twenty-six patients (aged 16-24 years) with bimaxillary protrusion, crowding <3 mm, requiring bilateral extraction of four first premolars were recruited. Permuted block randomization was done. Allocations were concealed in opaque envelopes which were numbered and sealed. Each patient's right and left quadrant was randomly assigned for premolar extraction. The extraction of the contralateral side was deferred until the commencement of retraction. The primary outcome was the rate of space closure, and the secondary outcomes were anchorage loss and canine rotation. Blinding was applied only during the outcome assessment. The independent t-test and Intraclass correlation tests were used for statistical evaluation.

Results: Twenty-four patients completed the study. The mean rate of space closure over a period of 4 months was found to be significantly higher for the recently extracted site (0.818±0.208) when compared with healed site(0.426±0.184)(p<0.001). The tipping of the canine was also significantly higher for the former (6.042°±1.398°) than the latter (5.125°±1.035°) (p<0.05). However, the amounts of anchorage loss and canine rotation were insignificant. No adverse effects were noted.

Conclusion: The rate of space closure at the recent extraction site was faster than that at the healed site. There was no significant difference in the mesial movement of anchorage molars or rotation of canines into the extraction site. The tipping of canines was significantly greater in the recent extracted quadrant. The results of this trial indicate a clinical recommendation to initiate orthodontic retraction immediately following therapeutic extractions and offer a practical, non-invasive, safe procedure for increasing the rate of tooth movement.

Objective: The purpose of this study was to compare the effects of cherry juice, coffee, coke, gastric acid, and the thermo-aging procedure (TAP) on the shear bond strength (SBS) of APC II, APC flash-free, and conventional ceramic brackets.

Methods: A total of 180 human premolar teeth were randomly divided into three major groups according to the type of ceramic bracket. Then, six subgroups (n=10) were established from each major group: Group 1: control; Group 2: only TAP; Group 3: 72 hours of cherry juice exposure + TAP; Group 4: 72 hours of coffee exposure + TAP; Group 5: 72 hours of coke exposure + TAP; and Group 6: 24 hours gastric acid exposure + TAP. SBS was assessed for each specimen using a universal test device, and the adhesive remnant index (ARI) was scored under a light microscope. Kruskal-Wallis and post-hoc Tamhane tests were used to analyze the data.

Results: Among the control groups, the highest SBS value belonged to conventional ceramic brackets (p<0.01). SBS values for all groups decreased as a result of each liquid and TAP. Gastric acid and coke had the greatest detrimental effects on SBS, while TAP had the least negative effects. The SBS values of APC II, APC flash-free, and conventional brackets were found to be statistically insignificant after different liquid exposures and TAP.

Conclusion: TAP and various fluids had a negative impact on the SBS value of ceramic brackets. SBS values, however, were still higher than clinically acceptable (8-9 MPa) values, even after exposure to gastric acid and coke.

Objective: The present study aimed to evaluate the effect of rapid maxillary expansion (RME) and face mask treatment on the upper airway in patients with maxillary retrusion in two dimensions using digital cephalograms and volumetric evaluation using acoustic rhinometric measurements.

Methods: A total of 22 individuals with a concave profile and skeletal and dental Class III malocclusion during growth and development with a mean age of 9.9±1.38 years were included in the study. A bonded RME appliance and a petit face mask were adapted for the patients. Before treatment (T0) and after maxillary protraction (T1), lateral cephalometric films and acoustic rhinometric recordings were obtained. The dependent sample t-test was used for statistical evaluation.

Results: Cephalometric analysis revealed forward movement of the maxilla and backward downward rotation of the mandible. A significant increase was observed in the nasopharyngeal and oropharyngeal regions of the upper airway. Three-dimensional evaluation of the upper airway by acoustic rhinometry revealed only an increase in the volumes of the left nasal cavity after decongestant administration. A statistically significant increase in acoustic rhinometric measurements in nasal valves. When the correlation of the cephalometric findings of the nasopharyngeal region with the acoustic rhinometry findings was examined, no statistically significant relationship was found.

Conclusion: As a result of this study, we observed an increase in the cephalometric measurements of the nasopharyngeal and oropharyngeal areas. A significant increase was observed in the minimal cross-sectional area measured by acoustic rhinometry.

Objective: To retrospectively evaluate the effects of single mandibular advancement (MA) and two-jaw surgery (2J-S) on the pharyngeal airway space (PAS) and hyoid position for the correction of skeletal Class II malocclusion.

Methods: Eleven adult patients who underwent only MA surgery and twelve adult patients who underwent Le Fort I maxillary impaction-MA surgery (2-JS) were included in the retrospective study. A total of 46 cephalometric recordings obtained before (T1) and after treatment (T2) were examined. Craniofacial changes, area, and linear measurements of the pharyngeal airway and hyoid bone position were obtained in both groups. The Wilcoxon signed-rank test was used to evaluate time-dependent changes within groups. The Mann-Whitney U test was used to compare differences between groups.

Results: Hyoid-Vert values increased significantly in both groups (MA, p<0.01; 2J-S, p<0.05); however, Hyoid-Hor values decreased significantly only in the 2J-S group (p<0.01). The anteroposterior dimensions of the airway increased in both groups, except for the PNS-P and PPS groups (p<0.01). Although a significant increase was observed in the nasopharyngeal area (A1) in the MA group (p<0.05), the decrease was found to be statistically significant in 2JG (p<0.01). Significant increases were found in the oropharyngeal (A2) and hypopharyngeal areas (A3) in both groups (p<0.01, p<0.05).

Conclusion: Both surgical procedures for the correction of Class II malocclusion resulted in increased hypopharyngeal, oropharyngeal, and total airway measurements.

Objective: This prospective study aimed to evaluate the analgesic effects of acetaminophen and Transcutaneous Electric Nerve Stimulation (TENS) therapy for pain control.

Methods: Forty orthodontic patients who underwent fixed orthodontic treatment were randomly assigned to one of 3 groups: (1) acetaminophen, (2) TENS therapy, or (3) control. Pain was evaluated at 12, 24, 36, and 48 hours after the placement of both 0.014" NiTi and 0.016" NiTi archwires using a 10 cm visual analogue scale (VAS). Because the data were found to be non-normal, Kruskal-Wallis test was employed for both stage I and stage II intra-group comparisons.

Results: For both stage I and stage II, evaluation of the VAS scores for all 3 groups at different time intervals showed that the difference between groups A and B was statistically insignificant (p>0.05). The scores of Group A compared to Group C were significant, and Group B compared to Group C showed significant values.

Conclusion: Both TENS and acetaminophen reduced the pain experienced by patients compared with the placebo group. The acetaminophen group showed VAS results similar to those of the TENS group.

Objective: To evaluate a newly designed minimally invasive palatal-plate face mask combination for the management of developing Class III malocclusion due to maxillary deficiency.

Methods: A sample of 16 Class III patients due to maxillary deficiency in the early mixed dentition (8 boys and 8 girls) aged between 7 and 9 years participated in this study and were treated with a combination of palatal plate face masks. Extra-oral elastics were attached between the intra-oral and extra-oral appliances; the elastics were set at 30° to the occlusal plane. The force magnitude was 250-300 g per quadrant. Cephalometric radiographs were taken before and immediately after maxillary protraction. In addition, skeletal measurements were measured, tabulated, and statistically analyzed. The pre- and post-protraction measurements were compared using the Student's t-test, and the significance level was set at a p-value <0.05.

Results: A statistically significant increase in SNA angle and maxillary length was observed by 3.13±1.52 degrees and 2.60±0.75 mm (p<0.05), respectively, indicating forward maxillary growth. The skeletal and soft tissue patterns were also improved, as evidenced by the statistically significant increase in the ANB angle, Wits appraisal, and H angle by 4.50±1.28 degrees, 5.30±1.86 mm, and 5.02±3.24 degrees (p<0.05), respectively. A favorable clockwise mandibular rotation was observed as evidenced by the increase in the SN/MP angle and the decrease in the SNB angle by 1.46±1.96 degrees and -1.38±1.86 degrees (p<0.05), respectively.

Conclusion: The palatal-plate facemask combination is an effective treatment alternative for Class III malocclusion due to maxillary deficiency with minimal pain and discomfort.