1.Effect of activation and preactivation on the mechanical behavior and neutral position of stainless steel and beta-titanium T-loops.
Saul Matos DE CASTRO ; Rui MOREIRA ; Ana Cristina BRAGA ; Afonso Pinhao FERREIRA ; Maria Cristina POLLMANN
The Korean Journal of Orthodontics 2015;45(4):198-208
OBJECTIVE: To quantify, for each activation, the effect of preactivations of differing distribution and intensity on the neutral position of T-loops (7-mm height), specifically the horizontal force, moment to force (M/F) ratio, and load to deflection ratio. METHODS: A total 100 loops measuring 0.017 x 0.025 inches in cross-section were divided into two groups (n = 50 each) according to composition, either stainless steel or beta-titanium. The two groups were further divided into five subgroups, 10 loops each, corresponding to the five preactivations tested: preactivations with occlusal distribution (0degrees, 20degrees, and 40degrees), gingival distribution (20degrees), and occlusal-gingival distribution (40degrees). The loops were subjected to a total activation of 6-mm with 0.5-mm iterations. Statistical analysis was performed using comprised ANOVA and Bonferoni multiple comparison tests, with a significance level of 5%. RESULTS: The location and intensity of preactivation influenced the force intensity. For the M/F ratio, the highest value achieved without preactivation was lower than the height of the loop. Without preactivation, the M/F ratio increased with activation, while the opposite effect was observed with preactivation. The increase in the M/F ratio was greater when the preactivation distribution was partially or fully gingival. CONCLUSIONS: Depending on the preactivation distribution, displacement of uprights is higher or lower than the activation, which is a factor to consider in clinical practice.
Analysis of Variance
;
Stainless Steel*
2.Upper airway dimensions and craniofacial morphology: A correlation study using cone beam computed tomography
Ana Rita da Rocha Martins de CARVALHO ; Maria Cristina Figueiredo POLLMANN ; Eugénio Joaquim Pereira MARTINS
The Korean Journal of Orthodontics 2024;54(5):274-283
Objective:
To determine the correlation between dentoskeletal parameters related to craniofacial morphology and the upper airway (UA) volume.
Methods:
Cone-beam computed tomography images of 106 randomly selected orthodontic patients were analyzed using NemoFab Ortho software. The dentoskeletal variables assessed were anterior facial height (AFH), posterior facial height (PFH), PFH/AFH ratio, hyoid position, maxillary width (MW), and palatal depth. The UA volume (evaluation in anatomical regions and as a whole) was also assessed using the same software. We also evaluated potential differences in UA variables between age and sex groups. The correlation between the dentoskeletal parameters and UA volume was calculated using the Pearson correlation coefficient (R). Analysis of variance and Student’s t test were performed to assess differences between age and sex for UA variables. Statistical analyses were performed using SPSS software (version 26 for Windows).
Results:
This study found that PFH, AFH, and MW were the dentoskeletal parameters most strongly correlated with UA volume. However, the ANB angle did not show any significant correlation with UA volume. Additionally, differences in UA volumes were observed between age groups. Sex differences were found in both the “8–12” and “≥ 16” age groups for oropharyngeal and pharyngeal volumes.
Conclusions
In conclusion, our findings indicate a significant correlation between UA volume and dentoskeletal parameters, particularly those related to facial height and MW.
3.Upper airway dimensions and craniofacial morphology: A correlation study using cone beam computed tomography
Ana Rita da Rocha Martins de CARVALHO ; Maria Cristina Figueiredo POLLMANN ; Eugénio Joaquim Pereira MARTINS
The Korean Journal of Orthodontics 2024;54(5):274-283
Objective:
To determine the correlation between dentoskeletal parameters related to craniofacial morphology and the upper airway (UA) volume.
Methods:
Cone-beam computed tomography images of 106 randomly selected orthodontic patients were analyzed using NemoFab Ortho software. The dentoskeletal variables assessed were anterior facial height (AFH), posterior facial height (PFH), PFH/AFH ratio, hyoid position, maxillary width (MW), and palatal depth. The UA volume (evaluation in anatomical regions and as a whole) was also assessed using the same software. We also evaluated potential differences in UA variables between age and sex groups. The correlation between the dentoskeletal parameters and UA volume was calculated using the Pearson correlation coefficient (R). Analysis of variance and Student’s t test were performed to assess differences between age and sex for UA variables. Statistical analyses were performed using SPSS software (version 26 for Windows).
Results:
This study found that PFH, AFH, and MW were the dentoskeletal parameters most strongly correlated with UA volume. However, the ANB angle did not show any significant correlation with UA volume. Additionally, differences in UA volumes were observed between age groups. Sex differences were found in both the “8–12” and “≥ 16” age groups for oropharyngeal and pharyngeal volumes.
Conclusions
In conclusion, our findings indicate a significant correlation between UA volume and dentoskeletal parameters, particularly those related to facial height and MW.
4.Upper airway dimensions and craniofacial morphology: A correlation study using cone beam computed tomography
Ana Rita da Rocha Martins de CARVALHO ; Maria Cristina Figueiredo POLLMANN ; Eugénio Joaquim Pereira MARTINS
The Korean Journal of Orthodontics 2024;54(5):274-283
Objective:
To determine the correlation between dentoskeletal parameters related to craniofacial morphology and the upper airway (UA) volume.
Methods:
Cone-beam computed tomography images of 106 randomly selected orthodontic patients were analyzed using NemoFab Ortho software. The dentoskeletal variables assessed were anterior facial height (AFH), posterior facial height (PFH), PFH/AFH ratio, hyoid position, maxillary width (MW), and palatal depth. The UA volume (evaluation in anatomical regions and as a whole) was also assessed using the same software. We also evaluated potential differences in UA variables between age and sex groups. The correlation between the dentoskeletal parameters and UA volume was calculated using the Pearson correlation coefficient (R). Analysis of variance and Student’s t test were performed to assess differences between age and sex for UA variables. Statistical analyses were performed using SPSS software (version 26 for Windows).
Results:
This study found that PFH, AFH, and MW were the dentoskeletal parameters most strongly correlated with UA volume. However, the ANB angle did not show any significant correlation with UA volume. Additionally, differences in UA volumes were observed between age groups. Sex differences were found in both the “8–12” and “≥ 16” age groups for oropharyngeal and pharyngeal volumes.
Conclusions
In conclusion, our findings indicate a significant correlation between UA volume and dentoskeletal parameters, particularly those related to facial height and MW.
5.Upper airway dimensions and craniofacial morphology: A correlation study using cone beam computed tomography
Ana Rita da Rocha Martins de CARVALHO ; Maria Cristina Figueiredo POLLMANN ; Eugénio Joaquim Pereira MARTINS
The Korean Journal of Orthodontics 2024;54(5):274-283
Objective:
To determine the correlation between dentoskeletal parameters related to craniofacial morphology and the upper airway (UA) volume.
Methods:
Cone-beam computed tomography images of 106 randomly selected orthodontic patients were analyzed using NemoFab Ortho software. The dentoskeletal variables assessed were anterior facial height (AFH), posterior facial height (PFH), PFH/AFH ratio, hyoid position, maxillary width (MW), and palatal depth. The UA volume (evaluation in anatomical regions and as a whole) was also assessed using the same software. We also evaluated potential differences in UA variables between age and sex groups. The correlation between the dentoskeletal parameters and UA volume was calculated using the Pearson correlation coefficient (R). Analysis of variance and Student’s t test were performed to assess differences between age and sex for UA variables. Statistical analyses were performed using SPSS software (version 26 for Windows).
Results:
This study found that PFH, AFH, and MW were the dentoskeletal parameters most strongly correlated with UA volume. However, the ANB angle did not show any significant correlation with UA volume. Additionally, differences in UA volumes were observed between age groups. Sex differences were found in both the “8–12” and “≥ 16” age groups for oropharyngeal and pharyngeal volumes.
Conclusions
In conclusion, our findings indicate a significant correlation between UA volume and dentoskeletal parameters, particularly those related to facial height and MW.
6.Upper airway dimensions and craniofacial morphology: A correlation study using cone beam computed tomography
Ana Rita da Rocha Martins de CARVALHO ; Maria Cristina Figueiredo POLLMANN ; Eugénio Joaquim Pereira MARTINS
The Korean Journal of Orthodontics 2024;54(5):274-283
Objective:
To determine the correlation between dentoskeletal parameters related to craniofacial morphology and the upper airway (UA) volume.
Methods:
Cone-beam computed tomography images of 106 randomly selected orthodontic patients were analyzed using NemoFab Ortho software. The dentoskeletal variables assessed were anterior facial height (AFH), posterior facial height (PFH), PFH/AFH ratio, hyoid position, maxillary width (MW), and palatal depth. The UA volume (evaluation in anatomical regions and as a whole) was also assessed using the same software. We also evaluated potential differences in UA variables between age and sex groups. The correlation between the dentoskeletal parameters and UA volume was calculated using the Pearson correlation coefficient (R). Analysis of variance and Student’s t test were performed to assess differences between age and sex for UA variables. Statistical analyses were performed using SPSS software (version 26 for Windows).
Results:
This study found that PFH, AFH, and MW were the dentoskeletal parameters most strongly correlated with UA volume. However, the ANB angle did not show any significant correlation with UA volume. Additionally, differences in UA volumes were observed between age groups. Sex differences were found in both the “8–12” and “≥ 16” age groups for oropharyngeal and pharyngeal volumes.
Conclusions
In conclusion, our findings indicate a significant correlation between UA volume and dentoskeletal parameters, particularly those related to facial height and MW.