Comparison of the efficiency of initial dental alignment with Invisalign® aligners changed every 7 or 14 days in mature adults: Randomized clinical trial.

OBJECTIVE: To compare the anterior crowding correction after sequential use of the first 5 aligners between two aligner exchange protocols (7 and 14 days) in mature adult patients. MATERIALS AND METHODS: Thirty-six patients over 35 years who received orthodontic treatment with Invisalign® were randomly allocated to two different aligner replacement sequence protocols: Group 1: exchange every 7 days (n = 18); and Group 2: exchange every 14 days (n = 18). All patients were scanned with iTero Element 5D® (Align Technology) in two treatment times: at pre-treatment (T1) and after using the first five aligners (T2). Little's Irregularity Index (LII) and arch widths were evaluated with OrthoCAD software. Intra and intergroup comparisons were performed with the dependent and independent t-tests. The results were considered significant for P < .05. RESULTS: Thirty-five patients completed the study. Both groups' maxillary and mandibular Irregularity Indexesi were significantly lower at T2. There was no significant difference in inter-canine, inter-premolar, and intermolar distances. G2 (14 days) presented a greater decrease in mandibular irregularity than G1 (7 days). CONCLUSION: Both exchange protocols (7 and 14 days) effectively correct anterior crowding in the initial phase of orthodontic treatment with aligners in mature adult patients. However, the 14-day exchange protocol provided a greater correction in mandibular anterior crowding in the evaluated period than the 7-day exchange protocol.

Maternal Risk Factors Associated with Negative COVID-19 Outcomes and Their Relation to Socioeconomic Indicators in Brazil.

BACKGROUND: This study aimed to analyze maternal risk factors associated with negative outcomes of COVID-19 and association with socioeconomic indicators in Brazil. METHODS: A cross-sectional study, with data from the Influenza Epidemiological Surveillance Information System (SIVEP-Flu) of pregnant women with COVID-19 and cases of hospitalization and death. For the analysis of risk factors and outcomes, the multiple logistic regression method was used. RESULTS: Pregnant women who had some risk factor represented 47.04%. The chance of death was 2.48 times greater when there was a risk factor, 1.55 for ICU admission and 1.43 for use of ventilatory support. The percentage of cure was 79.64%, 15.46% without any negative outcome, 4.65% death and 0.26% death from other causes. Pregnant women who did not take the vaccine represented 30.08%, 16.74% took it and 53.18% were not specified. The variables HDI, illiteracy, per capita income and urbanization did not influence the cases of COVID-19. CONCLUSIONS: Factors such as age, obesity, asthma and pregnancy were responsible for the increase in hospitalizations, respiratory complications and death. Vaccination reduced the risk of negative outcomes by 50%. There were no correlations between socioeconomic indicators and the negative outcomes of COVID-19 in pregnant women.

Incisor irregularity and dental arch dimensions changes in subjects with different severity of anterior crowding: a 37-year follow-up.

BACKGROUND: Occlusal stability is one of the goals of orthodontic treatment, and keeping teeth aligned in the long term is a challenge for the orthodontist. This study aimed to compare the long-term incisors irregularity and dental arches dimensions changes in subjects treated with 4 premolar extractions with different pretreatment Little's irregularity index (LII). The knowledge of long-term outcomes is evidence-based information for the prognosis of future treatments. METHODS: In total, 41 treated subjects were divided into two groups according to mandibular Little irregularity value at pretreatment (mild or severe). The maxillary and mandibular LII, transversal, and longitudinal widths were assessed at pretreatment, posttreatment, and 37-year posttreatment. Chi-square and independent t tests were used for intergroup comparison. RESULTS: The groups presented similar behavior for all stages of maxillary and mandibular arch dimensions changes. Maxillary irregularity was corrected in both groups after treatment, and the alignment was acceptable in the long term. In the mild group, the mandibular incisor irregularity returned to pretreatment values in the long term. The mandibular LII increased in the severe group but did not return to pretreatment values in the long term. CONCLUSIONS: The mild crowding group presented proportionally more relapse of mandibular incisor irregularity than the severe crowding group in the long term. Even so, the correction of mild and severe crowding with the extraction of 4 premolars showed satisfactory results in the long term, even with the presence of maturational changes and relapse.

Two-phase orthodontic treatment of two different types of tooth transposition in the same patient.

Orthodontic treatment is thoroughly planned considering the patient's facial and dental characteristics, the main complaint, treatment time and the orthodontist's experience. Transposition is a form of ectopia, in which two adjacent teeth exchange positions in the dental arch. Transposition can be partial or complete. This article reports the treatment of a female patient with two kinds of tooth transposition managed in the mixed and permanent dentitions. A girl, aged eight years and three months, came to routine paediatric consultation with an ectopic permanent mandibular left lateral incisor in the mixed dentition. Radiographic analysis indicated partial transposition of the permanent mandibular left lateral incisor and canine (Md.L2.C), and development of a complete tooth transposition between the permanent maxillary right first pre-molar and canine (Mx.C.P1). The patient was treated in two phases. The first, in the mixed dentition, and the second, in the permanent dentition with a three-year follow-up between them. These challenging treatment approaches are described in detail, including the mechanics used. The key points of this treatment were early diagnosis of the ectopic mandibular lateral incisor, use of light forces and interphase patient follow-up. These determined the best time to start the second treatment phase, enabling achievement of aesthetic and functional outcomes, and the results remained stable one year after the end of orthodontic treatment.

Orthodontic Movement of Central Incisor with Previously-healed Root Fracture associated with Unerupted Canines.

Teeth with root fracture may need orthodontic treatment. This case report presents the management of unerupted canines in a patient with previously-healed/untreated horizontal root fracture in the maxillary left central incisor. The malocclusion was treated maintaining pulp vitality considering the principles to improve the eruption path of maxillary canines and move short-rooted teeth. The root-fractured tooth remained symptomless after orthodontic treatment without significant adverse effects, and stayed stable following 2-year follow-up.

Dental inclination with self-ligating and conventional fixed appliances, with and without rapid maxillary expansion.

OBJECTIVE: To compare the labio- and buccolingual inclination of the anterior and posterior teeth in subjects treated with self-ligating and conventional fixed appliances with and without rapid maxillary expansion. METHODS: Seventy-one subjects with Class I malocclusion were divided into three groups. Group 1 comprised 24 subjects (17 female; seven male, with a mean age of 13.94 ± 2.87 years), treated with Roth's pre-adjusted fixed appliances. Group 2 comprised 24 subjects (14 female; 10 male, with a mean age of 13.85 ± 1.83 years) treated with Rapid Maxillary Expansion followed by Roth's pre-adjusted fixed appliances. Group 3 comprised 23 patients (12 female; 11 male, with a mean age of 14.75 ± 1.34 years) treated with Damon self-ligating bracket system. Buccolingual inclination was measured on digital dental models using a 3D software. Intergroup changes comparison was performed with one-way ANOVA, followed by Tukey tests. RESULTS: The left maxillary lateral incisor showed labial inclination in the conventional and RME groups, and palatal inclination in the Damon group. The Damon group showed greater buccal inclination in most posterior mandibular teeth during treatment than the conventional and RME groups. The right mandibular canine and lateral incisor showed greater labial inclination in the Damon group than in the RME group. CONCLUSIONS: There was greater buccal inclination of the posterior mandibular teeth and labial inclination of the right mandibular canine and lateral incisor in the Damon group.

Force level of small diameter nickel-titanium orthodontic wires ligated with different methods.

BACKGROUND: The aim of this study was to compare the deflection force in conventional and thermally activated nickel-titanium (NiTi) wires in passive (Damon Q) and active (Bioquick) self-ligating brackets (SLB) and in conventional brackets (CB) tied by two different methods: elastomeric ligature (EL) and metal ligature (ML). METHODS: Two wire diameters (0.014 and 0.016 in.) and 10 specimens per group were used. The specimens were assembled in a clinical simulation device and tested in an Instron Universal Testing Machine, with a load cell of 10 N. For the testing procedures, the acrylic block representative of the right maxillary central incisor was palatally moved, with readings of the force at 0.5, 1, 2, and 3 mm, at a constant speed of 2 mm/min and temperature of 36.5 °C. RESULTS: The conventional NiTi released higher forces than the thermally activated NiTi archwires in large deflections. In general, the SLB showed lower forces, while the ML had higher forces, with both showing a similar force release behavior, constantly decreasing as the deflection decreased. The EL showed an irregular behavior. The active SLB showed smaller forces than passive, in large deflections. CONCLUSIONS: The SLB and the ML exhibit standard force patterns during unloading, while the elastomeric ligatures exhibit a randomly distributed force release behavior.

External root resorption with the self-ligating Damon system-a retrospective study.

BACKGROUND: The aim of this study was to compare the degree of external apical root resorption (EARR) in patients treated with self-ligating Damon appliances and with conventional preadjusted appliances. METHODS: The sample comprised 52 patients, divided into two groups. Group 1 consisted of 25 patients treated with self-ligating Damon appliances, with an initial age of 16.04 years, final age of 18.06 years, and treatment time of 2.02 years. Group 2 consisted of 27 patients, treated with conventional preadjusted appliances, with an initial age of 16.77 years, final age of 18.47 years and treatment time of 1.70 years. The groups were matched regarding the initial and final ages, treatment time, type of malocclusion, and treatment protocol without extractions. Root resorption was evaluated on periapical radiographs of the maxillary and mandibular incisors at the end of orthodontic treatment with the scores of Levander and Malmgren. Intergroup comparisons of root resorption were performed with Mann-Whitney tests. RESULTS: No significant difference in the degree of root resorption between the two groups was found. CONCLUSIONS: Similar degrees of resorption can be expected after non-extraction treatment with Damon self-ligating or conventional preadjusted appliances.

Comparative study of torque expression among active and passive self-ligating and conventional brackets.

OBJECTIVE: The aim of this study was to compare torque expression in active and passive self-ligating and conventional brackets. METHODS: A total of 300 segments of stainless steel wire 0.019 x 0.025-in and six different brands of brackets (Damon 3MX, Portia, In-Ovation R, Bioquick, Roth SLI and Roth Max) were used. Torque moments were measured at 12°, 24°, 36° and 48°, using a wire torsion device associated with a universal testing machine. The data obtained were compared by analysis of variance followed by Tukey test for multiple comparisons. Regression analysis was performed by the least-squares method to generate the mathematical equation of the optimal curve for each brand of bracket. RESULTS: Statistically significant differences were observed in the expression of torque among all evaluated bracket brands in all evaluated torsions (p < 0.05). It was found that Bioquick presented the lowest torque expression in all tested torsions; in contrast, Damon 3MX bracket presented the highest torque expression up to 36° torsion. CONCLUSIONS: The connection system between wire/bracket (active, passive self-ligating or conventional with elastic ligature) seems not to interfere in the final torque expression, the latter being probably dependent on the interaction between the wire and the bracket chosen for orthodontic mechanics.

Class III Malocclusion Surgical-Orthodontic Treatment.

The aim of the present case report is to describe the orthodontic-surgical treatment of a 17-year-and-9-month-old female patient with a Class III malocclusion, poor facial esthetics, and mandibular and chin protrusion. She had significant anteroposterior and transverse discrepancies, a concave profile, and strained lip closure. Intraorally, she had a negative overjet of 5 mm and an overbite of 5 mm. The treatment objectives were to correct the malocclusion, and facial esthetic and also return the correct function. The surgical procedures included a Le Fort I osteotomy for expansion, advancement, impaction, and rotation of the maxilla to correct the occlusal plane inclination. There was 2 mm of impaction of the anterior portion of the maxilla and 5 mm of extrusion in the posterior region. A bilateral sagittal split osteotomy was performed in order to allow counterclockwise rotation of the mandible and anterior projection of the chin, accompanying the maxillary occlusal plane. Rigid internal fixation was used without any intermaxillary fixation. It was concluded that these procedures were very effective in producing a pleasing facial esthetic result, showing stability 7 years posttreatment.

Nasolabial angle at rest and upon smiling.

PURPOSE: The objectives of this study were 1) to determine the mean and SD of the nasolabial angle (NLA) and the linear measure pronasale (Prn)-A' at rest and upon smiling and 2) to determine the difference between smile and rest in participants with normal occlusion and facial harmony. MATERIALS AND METHODS: The sample consisted of 40 white Brazilian participants (20 of each gender) aged 20 to 30 years and with normal occlusion, a pleasant profile, and facial harmony. The measures NLA and Prn-A' were analyzed in profile photographs at rest and during smile, with a millimeter ruler in front of the profile during use of the Dolphin software. The statistical analysis included dependent t tests to compare the rest and smiling variables. RESULTS: The mean of the NLA at rest was 104.93°; it was 110.67° during smile; and the difference between them was statistically significant, with a mean of 5.74°. The mean of the linear variable Prn-A' at rest was 23.25 mm, whereas during smile it was 24.04 mm, and the difference between them was statistically significant, with a mean of 0.79 mm. CONCLUSIONS: The variability in the NLA and Prn-A' at rest and upon smiling was found to be significant in a normal sample, and it should be considered as a diagnostic tool in the treatment planning for sagittal dentoskeletal deformities.

Comparison of topical and infiltration anesthesia for orthodontic mini-implant placement.

OBJECTIVE: To compare the acceptability and effectiveness of topical and infiltration anesthesia for placement of mini-implants used as temporary anchorage devices. METHODS: The sample comprised 40 patients, 17 males and 23 females, whose mean age was of 26 years and who were all undergoing orthodontic treatment and in need for anchorage reinforcement. Mini-implants were bilaterally placed in the maxilla of all individuals, with infiltration anesthesia on one side and topical anesthesia on the other. These 40 patients completed two questionnaires, one before and another after mini-implant placement, and pain was measured through a visual analog scale (VAS). The data collected were analyzed using descriptive statistics and the measurements of pain were compared by means of Mann-Whitney non-parametric test. RESULTS: It was found that 60% of patients felt more comfortable with the use of topical anesthesia for mini-implant placement; 72.5% of patients described the presence of pressure during placement of the anchorage device as the most unpleasant sensation of the entire process; 62.5% of patients felt more pain with the use of topical anesthesia. CONCLUSION: It was concluded that patients had less pain with the use of infiltration anesthesia, and also preferred this type of anesthetic.

Dentoskeletal effects of Class II malocclusion treatment with the Twin Block appliance in a Brazilian sample: a prospective study.

OBJECTIVE: The aim of this study was to assess the dentoskeletal effects of Class II malocclusion treatment performed with the Twin Block appliance. METHODS: The experimental group comprised 20 individuals with initial mean age of 11.76 years and treated for a period of 1.13 years. The control group comprised 25 individuals with initial mean age of 11.39 years and a follow-up period of 1.07 years. Lateral cephalograms were taken at treatment onset and completion to assess treatment outcomes. Intergroup comparison was performed by means of the chi-square and independent t tests. RESULTS: The Twin Block appliance did not show significant effects on the maxillary component. The mandibular component showed a statistically significant increase in the effective mandibular length (Co-Gn) and significant improvement in the maxillomandibular relationship. The maxillary and mandibular dentoalveolar components presented a significant inclination of anterior teeth in both arches. The maxillary incisors were lingually tipped and retruded, while the mandibular incisors were labially tipped and protruded. CONCLUSIONS: The Twin Block appliance has great effectiveness for correction of skeletal Class II malocclusion in individuals with growth potential. Most changes are of dentoalveolar nature with a large component of tooth inclination associated with a significant skeletal effect on the mandible.

Class II malocclusion treatment with the Herbst appliance in patients after the growth peak.

OBJECTIVE: The objective of this study was to evaluate dentoskeletal effects in the treatment of Class II malocclusion performed with the Herbst appliance in patients at post-peak stage of growth. METHODS: The sample consisted of 16 patients with Class II malocclusion and average initial and final ages of 14.04 (ranging from 11.50 to 35.66) and 17.14 (ranging from 13.68 to 38.64) years, respectively, who were treated for an mean time of 2.52 years. Lateral cephalograms were obtained at treatment onset (T1) and completion (T2) to evaluate the effects of therapy. Initial dental casts were also used to evaluate the overjet and the anteroposterior severity of molar relationship at treatment onset. The cephalometric changes between initial and final stages were compared by means of the non-parametric Wilcoxon test. RESULTS: The results showed that the Herbst appliance did not promote significant changes in the maxillary component and the effective length of the mandible significantly increased without improving the maxillomandibular relationship. Changes in the maxillary and mandibular dentoalveolar components revealed that the maxillary incisors exhibited retrusion and lingual tipping, while the mandibular incisors presented increased protrusion and buccal tipping. The dental relationships exhibited significant improvements with the treatment. CONCLUSION: Based on the present results, it was concluded that the effects of treatment performed with the Herbst appliance in patients at post-peak stage of growth are predominantly of dentoalveolar nature.

Comparison of the changes of alveolar bone thickness in maxillary incisor area in extraction and non-extraction cases: computerized tomography evaluation.

OBJECTIVE: To compare, through computed tomography, alveolar bone thickness changes at the maxillary incisors area during orthodontic treatment with and without tooth extraction. METHODS: Twelve patients were evaluated. They were divided into 2 groups: G1--6 patients treated with extraction of right and left maxillary first premolars, with mean initial age of 15.83 years and mean treatment length of 2.53 years; G2--6 patients treated without extraction, with mean initial age of 18.26 years and mean treatment length of 2.39 years. Computed tomographies, lateral cephalograms and periapical radiographs were used at the beginning of the treatment (T1) and 18 months after the treatment had started (T2). Extraction space closure occurred in the extraction cases. Intragroup and intergroup comparisons were performed by dependent and independent t test, respectively. RESULTS: In G1, the central incisor was retracted and uprighted, while in G2 this tooth showed vestibularization. Additionally, G1 presented a higher increase of labial alveolar bone thickness at the cervical third in comparison with G2. The incidence of root resorption did not present significant differences between groups. CONCLUSION: There were no changes in alveolar bone thickness when extraction and nonextraction cases were compared, except for the labial alveolar bone thickness at the cervical third of maxillary incisors.

Cephalometric changes in Class II division 1 patients treated with two maxillary premolars extraction.

OBJECTIVE: The purpose of this study was to evaluate the cephalometric alterations in patients with Angle Class II division 1 malocclusion, orthodontically treated with extraction of two maxillary premolars. METHODS: The sample comprised 68 initial and final lateral cephalograms of 34 patients of both sex (mean initial age of 14.03 years and mean final age of 17.25 years), treated with full fixed appliances and extraction of the first maxillary premolars. In order to evaluate the alterations due the treatment between initial and final phases, the dependent t test was applied to the studied cephalometric variables. RESULTS: The dentoskeletal alterations due to extraction of two maxillary premolars in the Class II division 1 malocclusion were: maxillary retrusion, improvement of the maxillomandibular relation, increase of lower anterior facial height, retrusion of the maxillary incisors, buccal inclination, protrusion and extrusion of the mandibular incisors, besides the reduction of overjet and overbite. The tissue alterations showed decrease of the facial convexity and retrusion of the upper lip. CONCLUSIONS: The extraction of two maxillary premolars in Class II division 1 malocclusion promotes dentoskeletal and tissue alterations that contribute to an improvement of the relation between the bone bases and the soft tissue profile.

Long-term stability of maxillary anterior alignment in non-extraction cases.

OBJECTIVE: The purpose of this retrospective study was to evaluate long-term stability of maxillary incisors alignment in cases submitted to non-extraction orthodontic treatment. METHODS: The sample comprised 23 patients (13 female; 10 male) at a mean initial age of 13.36 years (SD = 1.81 years), treated with fixed appliances. Dental cast measurements were obtained at three different time points (T1 - pretreatment, T2 - posttreatment and T3 - long-term posttreatment). Variables assessed in maxillary arch were Little Irregularity Index, intercanine, interpremolar and intermolar widths, arch length and perimeter. The statistical analysis was performed by one-way ANOVA and Tukey tests when necessary. Pearson' correlation coefficients were used to investigate possible associations between the evaluated variables. RESULTS: There was no significant change in most arch dimension measurements during and after treatment, however, during the long-term posttreatment period, it was observed a significant maxillary incisors crowding relapse. CONCLUSIONS: The maxillary incisors irregularity increased significantly (1.52 mm) during long-term posttreatment. None of the studied clinical factors demonstrated to be predictive of the maxillary crowding relapse.

Stability of molar relationship after non-extraction Class II malocclusion treatment.

OBJECTIVE: This study aimed to evaluate the stability of molar relationship after non-extraction treatment of Class II malocclusion. METHODS: The sample comprised 39 subjects (16 females, 23 males) with initial Class II malocclusion treated with no extractions, using fixed appliances. Mean age at the beginning of treatment was 12.94 years, at the end of treatment was 15.14 years and at post-retention stage was 21.18 years. Mean treatment time was 2.19 years and mean time of post-treatment evaluation was 6.12 years. To verify the influence of the severity of initial Class II molar relationship in stability of molar relationship, the sample was divided into two groups, one presenting a ½-cusp or ¾-cusp Class II molar relationship, and the other with full-cusp Class II molar relationship. In dental casts from initial, final and post-retention stages, molar, first and second premolars and canine relationships were measured. Data obtained were analyzed by dependent ANOVA, Tukey and Pearson's correlation tests, as well as independent t test between the two groups divided by severity of initial molar relationship. RESULTS: There was a non-statistically significant 0.12-mm relapse of molar relationship. The initial severity of Class II molar relationship was not correlated to relapse in the post-retention period. When compared, the two groups showed no difference in relapse of molar relationship. CONCLUSIONS: It was concluded that correction of Class II molar relationship is stable and initial severity does not influence relapse of molar relationship.