Comparison of torque expression among passive self-ligating brackets with different slot depths: An in vitro study.

INTRODUCTION: The aim of this study was to assess the interaction between a 0.019×0.025-inch (″) stainless steel archwire and two types of passive self-ligating brackets with the same slot height (0.022″) and different slot depths (0.028″ and 0.026″, and to measure the archwire/slot play as well as to compare the torque expression with archwire torsions of 12°, 24°, and 36°. MATERIAL AND METHODS: An experimental device was developed along with a universal testing machine to measure torque expression in two types of brackets with 0.028″ and 0.026″ slot depths. Analysis of variance (ANOVA) and Tukey's test were performed to identify the differences between groups. RESULTS: The 0.026″ slot bracket presented greater archwire/slot play when compared to the 0.028″ bracket. Torque expression with torsions of 24° and 36° were significantly higher in the 0.028″ depth brackets when compared to the 0.026″ depth brackets. CONCLUSION: The 0.022″×0.026″ passive self-ligating brackets attached with a 0.019″×0.025″ stainless steel archwire provided no greater torque control when compared to 0.022″×0.028″ passive self-ligating brackets.

Short-term assessment of pain and discomfort during rapid maxillary expansion with tooth-bone-borne and tooth-borne appliances: randomized clinical trial.

OBJECTIVE: The aim of this randomized clinical trial was to evaluate and compare, during the first week of rapid maxillary expansion (RME), the impact caused by two types of appliances: Hyrax and Hybrid Hyrax. METHODS: Forty-two patients who met the eligibility criteria (aged 11-14 years, with transverse maxillary deficiency, posterior crossbite, and presence of maxillary first premolars and first permanent molars) were selected and randomly divided into two groups: TBB GROUP (tooth-bone-borne expander), treated with Hybrid Hyrax (12 females and 9 males, mean age 13.3 ± 1.3 years), and TB GROUP (tooth-borne expander), treated with Hyrax (5 females and 16 males, mean age 13.3 ± 1.4 years). Pain and discomfort were assessed in two times: after the first day of activation (T1) and four days after, by means of the numerical rate scale and the instrument MFIQ (Mandibular Functional Impairment Questionnaire). Descriptive statistics and the Mann-Whitney test were used for comparison between groups and between sexes. A 5% significance level was adopted. RESULTS: Both appliances had a negative impact, generating pain and discomfort, and reducing functional capacity. However, the scores obtained were of low intensity and no significant differences were observed between the groups. Considering sexes, there were statistically significant differences, with the female sex presenting higher scores for pain and functional limitation. CONCLUSIONS: Despite causing impact in pain and increase in the functional limitation, these changes were of low intensity, with no statistical difference between the groups. Females were more sensitive to the impact caused by the RME.

Short-term assessment of pain and discomfort during rapid maxillary expansion with tooth-bone-borne and tooth-borne appliances: randomized clinical trial

ABSTRACT Objective: The aim of this randomized clinical trial was to evaluate and compare, during the first week of rapid maxillary expansion (RME), the impact caused by two types of appliances: Hyrax and Hybrid Hyrax. Methods: Forty-two patients who met the eligibility criteria (aged 11-14 years, with transverse maxillary deficiency, posterior crossbite, and presence of maxillary first premolars and first permanent molars) were selected and randomly divided into two groups: TBB GROUP (tooth-bone-borne expander), treated with Hybrid Hyrax (12 females and 9 males, mean age 13.3 ± 1.3 years), and TB GROUP (tooth-borne expander), treated with Hyrax (5 females and 16 males, mean age 13.3 ± 1.4 years). Pain and discomfort were assessed in two times: after the first day of activation (T1) and four days after, by means of the numerical rate scale and the instrument MFIQ (Mandibular Functional Impairment Questionnaire). Descriptive statistics and the Mann-Whitney test were used for comparison between groups and between sexes. A 5% significance level was adopted. Results: Both appliances had a negative impact, generating pain and discomfort, and reducing functional capacity. However, the scores obtained were of low intensity and no significant differences were observed between the groups. Considering sexes, there were statistically significant differences, with the female sex presenting higher scores for pain and functional limitation. Conclusions: Despite causing impact in pain and increase in the functional limitation, these changes were of low intensity, with no statistical difference between the groups. Females were more sensitive to the impact caused by the RME.

RESUMO Objetivo: O objetivo deste ensaio clínico randomizado foi avaliar e comparar, durante a primeira semana de expansão rápida da maxila (ERM), o impacto causado por dois tipos de aparelhos: Hyrax e Hyrax Híbrido. Métodos: Quarenta e dois pacientes que atendiam aos critérios de seleção (idade de 11 a 14 anos, com deficiência transversal da maxila, mordida cruzada posterior e presença de primeiros pré-molares e primeiros molares permanentes superiores) foram selecionados e divididos aleatoriamente em dois grupos: Grupo DOS (expansor dento-osseossuportado), tratado com Hyrax Híbrido (12 mulheres e 9 homens, idade média 13,3 ± 1,3 anos), e Grupo DS (expansor dentossuportado), tratado com Hyrax (5 mulheres e 16 homens, idade média de 13,3 ± 1,4 anos). A dor e o desconforto foram avaliados em dois momentos: após o primeiro dia de ativação (T1) e após quatro dias, por meio da escala de frequência numérica e do instrumento MFIQ (Questionário de Limitação Funcional Mandibular). A estatística descritiva e o teste de Mann-Whitney foram utilizados para comparação entre os grupos e entre os sexos. Adotou-se nível de significância de 5%. Resultados: Ambos os aparelhos tiveram impacto negativo, gerando dor e desconforto e reduzindo a capacidade funcional. No entanto, os escores obtidos foram de baixa intensidade e não foram observadas diferenças significativas entre os grupos. Considerando os sexos, houve diferenças estatisticamente significativas, com o sexo feminino apresentando maiores escores para dor e limitação funcional. Conclusões: Apesar de causar impacto na dor e aumento na limitação funcional, essas alterações foram de baixa intensidade, sem diferença estatística entre os grupos. As mulheres foram mais sensíveis ao impacto causado pela ERM.

Safe sites for orthodontic miniscrew insertion in the infrazygomatic crest area in different facial types: A tomographic study.

INTRODUCTION: Temporary skeletal anchorage devices (TSADs) are used to obtain skeletal anchorage for orthodontic treatment. Their insertion in the infrazygomatic crest (IZC) allows efficient orthodontic mechanics. Different facial types have different bone configurations. We aimed to evaluate the differences in bone thicknesses in the IZC area among patients of each facial type to determine a safe zone for TSAD insertion. METHODS: For this retrospective study, 86 cone-beam computed tomography (CBCT) scans were divided into 3 groups according to the facial type: group I, 24 CBCT scans of hyperdivergent patients; group II, 30 scans of neutral patients; and group III, 32 scans of hypodivergent patients. The buccal alveolar bone thickness was measured in 6 zones between the second premolar and distal root of the second molar, 5, 7, 9, and 11 mm apical to the alveolar crest. RESULTS: The IZC areas with minimum thickness for TSAD insertion follows: group I, between first and second molars at 11 mm from the alveolar crest, mesial root of the second molar at 9 mm from the crest, and distal root of the second molar at 11 mm from the crest; groups II and III, between first and second molars at 11 mm from the crest and mesial root of the second molar at 11 mm from the crest. CONCLUSIONS: The safe zones for IZC miniscrew insertion are located 11 mm from the alveolar crest between the maxillary first and second molars and on the mesial root of the second molar for all the 3 facial types.

Dentoskeletal changes due to rapid maxillary expansion in growing patients with tooth-borne and tooth-bone-borne expanders: A randomized clinical trial.

OBJECTIVES: To compare, using cone-beam computed tomography, the dentoskeletal changes in rapid maxillary expansion with tooth-bone-borne (Hybrid Hyrax) and tooth-borne (Hyrax) appliances. SETTING AND SAMPLE POPULATION: Forty-two patients who met the eligibility criteria (aged 11-14 years; transverse maxillary deficiency, posterior crossbite, and presence of upper first premolars and molars) were screened and allocated into two groups: HHG (treatment with Hybrid Hyrax) and HG (treatment with Hyrax). MAIN OUTCOME MEASURES: The primary outcomes included nasomaxillary dimensional changes. CBCT was performed before and 3 months after the activation phase. Measurements were performed using Dolphin® . Baseline data were compared using one-way ANOVA. For intergroup comparison, ANCOVA was used to analyze the initial age, appliance activations (mm), and mid-palatal suture maturation data as covariates. Statistical significance was set at 5%. RESULTS: The premolar region in HHG showed increased skeletal changes than in HG, with the difference being 1.5 mm (0.5; 2.6) in the nasal cavity (P = .004), 1.4 mm (0.3; 2.5) in the nasal floor (P = .019), and 1.1 mm (0.2; 2.1) in the maxilla (P = .022). The molar region in HHG showed increased skeletal changes with the difference being 0.9 mm (0.2; 1.5) in the nasal cavity (P = .005), and 0.9 mm (0; 1.8) in the maxilla (P = .042) than in HG. Premolar inclination was higher in HG. CONCLUSION: Hybrid Hyrax showed more skeletal changes and fewer dental side effects, especially in the first premolar region. The amount of activation influenced the higher nasal skeletal changes in the Hybrid hyrax group.

A method to compute the effect of vertical mulching on the reduction of surface runoff.

Six plots (three as controls) were established in southern Brazil to assess the reduction in runoff by vertical mulching (vm). In the other three, ditches (0.08-m wide, 0.4-m deep) were cut perpendicular to the slope, 2-m and 12-m upslope from the bottom of the plot where a flume was installed to measure runoff. Three simulated rainfalls (80 mm h-1 for 120 min, 80 mm h-1 for 65 min, 97 mm h-1 for 65 min) were applied with a sprinkler system to generate runoff. Compared to the controls, vm delayed its beginning by 10 to 20 min and reduced its volume by 34 to 39%, because initially all and later some runoff was caught in the ditches from where it infiltrated into the surrounding soil. Based on the experimental results, we derived a method to compute the runoff reduction by vm as influenced by ditch spacing (ds), initial soil moisture content (θi), and rainfall rate and duration. Computations for a combination of four ds (5 to 20 m), five θi (16 to 32%-vol), and three rainfall regimes (124 mm h-1 for 20 min, 66 mm h-1 for 60 min, and 42 mm h-1 for 120 min) showed an increasing runoff reduction as ds or θi decreased. In some cases, runoff was even completely prevented. The reductions were larger in the 60-min than in the 20-min rainfall. For the 120-min rainfall, there was no runoff with any combination of ds and θi.

Stress distribution analysis in anterior teeth caused by several retraction mechanics.

INTRODUCTION: Orthodontic retraction of the anterior teeth is indicated when the patient has a malocclusion with protrusion of the incisors. Several mechanics are indicated to perform this retraction. OBJECTIVE: The objective of this study was to compare the strains generated by four different types of retraction mechanics along the roots of the anterior teeth. METHODS: A photoelastic model simulating an arch with first premolars extraction was made. Sixty retraction archwires were prepared, including fifteen for each type of mechanics evaluated: sliding, teardrop loop spring, T-loop spring and double key loop archwire. The strains were observed in two perspectives: occlusal and oblique. In the occlusal perspective, strains were compared among the six anterior teeth. From the oblique perspective, strains were compared among the thirds of the left canine root. RESULTS: In the occlusal perspective, the teardrop loop spring mechanics presented greater strains, followed by T-loop spring, double key loop archwire and sliding mechanics. In all mechanics, strains were more concentrated in the canines than in the incisors. From the oblique perspective, the teardrop loop mechanics generated greater strains in the cervical regions of the canine, and in the apical regions, no differences were found in strains among the four types of mechanics. In the same mechanics, greater strains were present in the cervical zones. CONCLUSION: The teardrop loop spring retraction mechanic presented the greatest mean strain, and the sliding retraction mechanic presented the lowest mean strain on the root of anteroinferior teeth in the occlusal and oblique perspectives.

Three-dimensional evaluation of dental decompensation and mandibular symphysis remodeling on orthodontic-surgical treatment of Class III malocclusion.

INTRODUCTION: The purposes of this research were to identify the buccolingual inclinations of the mandibular teeth and the mandibular symphysis remodeling that result from the orthodontic decompensation movement. METHODS: The sample consisted of 30 adults with Class III dentofacial deformity, who had presurgical orthodontic treatment. Three-dimensional images were generated by cone-beam computed tomography scans at 2 different times (initial and before orthognathic surgery). Three-dimensional virtual models were obtained and superimposed using automated voxel-based registration at the mandible to evaluate B-point displacement, mandibular molar and incisor decompensation movement, and symphysis inclination and thickness. The 3-dimensional displacements of landmarks at the symphysis were quantified and visualized with color-coded maps using 3D Slicer (version 4.0; www.slicer.org) software. RESULTS: The measurements showed high reproducibility. The patients presented mandibular incisor proclination, which was consistent with the movement of tooth decompensation caused by the presurgical orthodontic treatment. Statistically significant correlations were found between the inclination of the mandibular incisors, symphysis inclination, and B-point displacement. Regarding the thickness of the symphysis and the inclination of the incisors, no statistically significant correlation was found. CONCLUSIONS: The buccolingual orthodontic movement of the mandibular incisors with presurgical leveling is correlated with the inclination of the mandibular symphysis and repositioning of the B-point but not correlated to the thickness of the symphysis.

Stress distribution analysis in anterior teeth caused by several retraction mechanics

ABSTRACT Introduction: Orthodontic retraction of the anterior teeth is indicated when the patient has a malocclusion with protrusion of the incisors. Several mechanics are indicated to perform this retraction. Objective: The objective of this study was to compare the strains generated by four different types of retraction mechanics along the roots of the anterior teeth. Methods: A photoelastic model simulating an arch with first premolars extraction was made. Sixty retraction archwires were prepared, including fifteen for each type of mechanics evaluated: sliding, teardrop loop spring, T-loop spring and double key loop archwire. The strains were observed in two perspectives: occlusal and oblique. In the occlusal perspective, strains were compared among the six anterior teeth. From the oblique perspective, strains were compared among the thirds of the left canine root. Results: In the occlusal perspective, the teardrop loop spring mechanics presented greater strains, followed by T-loop spring, double key loop archwire and sliding mechanics. In all mechanics, strains were more concentrated in the canines than in the incisors. From the oblique perspective, the teardrop loop mechanics generated greater strains in the cervical regions of the canine, and in the apical regions, no differences were found in strains among the four types of mechanics. In the same mechanics, greater strains were present in the cervical zones. Conclusion: The teardrop loop spring retraction mechanic presented the greatest mean strain, and the sliding retraction mechanic presented the lowest mean strain on the root of anteroinferior teeth in the occlusal and oblique perspectives.

RESUMO Introdução: A retração ortodôntica dos dentes anteriores é indicada quando o paciente apresenta má oclusão com vestibularização dos incisivos. Diferentes mecânicas são indicadas para realizar essa retração. Objetivo: O objetivo do presente estudo foi comparar as tensões geradas por quatro diferentes tipos de mecânicas de retração nas raízes dos dentes anteriores. Métodos: Um modelo fotoelástico foi confeccionado simulando uma arcada com os primeiros pré-molares extraídos. Foram preparados 60 arcos de retração, sendo quinze para cada tipo de mecânica avaliada: deslizamento, alça de Bull, alça em T e arco de dupla chave. As tensões foram observadas em duas perspectivas: oclusal e oblíqua. Na vista oclusal, as tensões foram comparadas entre os seis dentes anteriores. Na vista oblíqua, as tensões foram comparadas entre os terços radiculares do canino esquerdo. Resultados: Na vista oclusal, a mecânica com alça de Bull apresentou maiores tensões, seguida da alça em T, arco de dupla chave e mecânica de deslizamento. Em todas as mecânicas, as tensões se concentraram mais nos caninos do que nos incisivos. Na vista oblíqua, a mecânica com alça de Bull gerou maiores tensões nas regiões cervicais dos caninos; nas regiões apicais, não houve diferenças nas tensões entre os quatro tipos de mecânicas. Dentro de uma mesma mecânica, as maiores tensões estiveram presentes nas regiões cervicais. Conclusão: A mecânica de retração com alça de Bull apresentou a maior média de tensões, e a mecânica de retração por deslizamento apresentou a menor média de tensões na raiz dos dentes anteroinferiores, nas vistas oclusal e oblíqua.

Micro-osteoperforation effectiveness on tooth movement rate and impact on oral health related quality of life.

OBJECTIVES: To investigate the effect of micro-osteoperforation (MOP) on the rate of tooth movement (RTM), space closure duration, and oral health-related quality of life (OHRQoL) during completion of anterior retraction in patients undergoing combined orthodontic-surgical treatment after premolar extraction and decompensation with sliding mechanics. MATERIALS AND METHODS: Twenty-four participants with indications for premolar extractions were randomly allocated to treatment with conventional sliding mechanics (control group; CG) or with to treatment in which three MOPs were performed every activation (experimental group; EG). Dental impressions were taken monthly until space closure was completed and dental casts were converted to three-dimensional models. After the anterior retraction procedure, Oral Health Impact Profile (OHIP-14) questionnaires were filled out at 4 and 72 hours. RESULTS: Eighteen patients (7 men and 11 women) remained in the trial until space closure was completed (mean follow-up period = 247 days). For full space closure RTM, no significant difference (P = .492) was found between groups (0.614 mm/month for the CG; 0.672 mm/month for the EG). The RTM for different time points, groups, time frames and their interaction were statistically different (P < .05). In multiple correlation analysis, the RTM significantly decreased over time for both groups (P < .05). The OHRQoL scores were significantly higher (worse) for the EG. The psychological, physical and social disabilities, and handicap domains displayed significant differences between the two groups. CONCLUSION: Use of MOPs did not change the full space closure RTM, while it had a negative impact on OHRQoL.

Effect of orthodontic treatment on alveolar bone thickness in adults: a systematic review.

OBJECTIVES: This review aimed at evaluating changes in alveolar bone thickness after completion of orthodontic treatment. METHODS: Only prospective clinical studies that reported bone thickness in adult patients undergoing non-surgical orthodontic treatment were considered eligible. MEDLINE, EMBASE and LILACS databases were searched for articles published up to July 2018. RESULTS: A total of 12 studies met the selected criteria. Most of the studies showed that orthodontic treatment produces a reduction in bone thickness of incisors, mainly at the palatal side. CONCLUSION: On patients undergoing different orthodontic treatment techniques, there was a significant bone thickness reduction, mainly on the palatal side. CLINICAL RELEVANCE: These findings are relevant and have to be considered in diagnosis and planning of tooth movement, in order to prevent the occurrence of dehiscence and fenestration in alveolar bone.

Maxillary protraction with rapid maxillary expansion and facemask versus skeletal anchorage with mini-implants in class III patients: a non-randomized clinical trial.

BACKGROUND: The use of skeletal anchorage devices for maxillary protraction in patients with class III malocclusion due to deficiency in the middle third of the face has been shown to be a promising approach to treatment of these patients. The aim of this study was to evaluate the treatment of class III patients with maxillary retrusion, using orthodontic mini-implants (MI) associated with intermaxillary elastics in comparison with the rapid maxillary expansion and facemask protocol (RME/FM). METHODS: In this prospective non-randomized clinical trial, the sample of 24 participants between 7 and 12 years of age (median age of 10.0 years and interquartile range = 3.0 years), at the stage prior to the pre-pubertal growth spurt, was divided in two groups. In group facemask (FM) (n = 12), the individuals received orthopedic treatment with RME/FM. In group MI (n = 12), two mini-implants were inserted in the region close to the maxillary first molar roots, and the other two in the region of the mandibular canines. Initial and final lateral teleradiographs were taken for cephalometric evaluation of all the cases. Statistical analysis included the Mann-Whitney, Wilcoxon, and Fisher's exact tests. The level of significance was 5% (α = 0.05). RESULTS: Improvement was verified in the facial profile and occlusion of the participants, showing advancement of the maxilla in the two groups, with significant differences (P ≤ 0.05) between T0 and T1 in the following measurements: SNA, ANB, Wits, Co-A, Co-Gn, NAP, A-Npog, overjet, and molar relationship. There was no statistically significant intergroup difference (P > 0.05) in the cephalometric measurements evaluated, but the time of treatment was significant, and was faster for group MI. CONCLUSIONS: The protocol with mini-implants may be an option for the correction of Class III due to maxillary deficiency.

An Oral Health-Related Quality of Life Comparison Between Adults With Unilateral Cleft Lip and Palate and Class III Malocclusion.

OBJECTIVE: To compare oral health-related quality of life (OHRQoL) before treatment of adults with unilateral cleft lip and palate (UCLP) and surgical Class III malocclusion, and to consider if clefts needing different orthodontic treatment protocols could influence people's self-perception. DESIGN: Cross sectional. SETTING: Cleft Lip and Palate Center and Clinic of Orthognathic Surgery from a School of Dentistry. PARTICIPANTS: A sample of adults with repaired nonsyndromic UCLP (n = 52) which was age- and sex-matched with a noncleft Class III malocclusion sample seeking orthognathic surgery (n = 51). In turn, the cleft group was subdivided according to treatment planning into nonsurgical orthodontic and surgical orthodontic approaches. MAIN OUTCOME MEASURE: The whole sample was assessed using the short-form oral health impact profile (OHIP-14), with higher scores indicating a poorer OHRQoL. Statistical comparisons were performed with Mann-Whitney U and Kruskal-Wallis tests, and effect size. Bonferroni adjustment was used for post hoc tests (P < .017). RESULTS: The OHIP-14 scores of the UCLP and Class III groups were significantly different (P = .001, η2 = 0.108), and higher in Class III. The largest commitment was in the physical disability, physical pain, and psychological disability domains. In addition, no differences were found when the UCLP treatment planning was considered. CONCLUSION: Surgical Class III malocclusion have a poorer OHRQoL when compared to patients with UCLP, irrespective of whether they are treated surgically or orthodontically. Therefore, the greater commitment of OHRQoL appears to be influenced by the etiology of Class III, and not by treatment plan.

Perception of attractiveness of missing maxillary lateral incisors replaced by canines.

OBJECTIVE: The aim of this study was to evaluate the degree of perception of attractiveness of the smile among dentists, dental students, and lay persons in cases of agenesis of the maxillary lateral incisors replaced by canines for space closure. METHODS: A smiling front view extraoral photograph of a 20-year-old woman was digitally altered simulating agenesis and its treatment, by means of: repositioning, reshaping or bleaching the canine, and gingival contour. A questionnaire was distributed to individuals of the three groups (n= 150), with a view to evaluating their degree of esthetic perception. An attractiveness scale was also used, with '0' representing unattractive and '10', very attractive. RESULTS: In the comparative evaluation among all the photographs, the original image obtained the highest level of acceptance. Photograph 'i' (agenesis of both lateral incisors treated with reposition and reshaping of the canines) was ranked as the least attractive by the dentists, whereas the student and lay persons ranked photograph 'f' (agenesis of both lateral incisors treated with reposition of the canines, gingival contour, bleaching and reshaping) as the worst. CONCLUSION: The methods of treatment most accepted among the dentists and students were those that involved changes in the gingival contour, whereas among lay persons, they were those that involved only reshaping.

Perception of attractiveness of missing maxillary lateral incisors replaced by canines

ABSTRACT Objective: The aim of this study was to evaluate the degree of perception of attractiveness of the smile among dentists, dental students, and lay persons in cases of agenesis of the maxillary lateral incisors replaced by canines for space closure. Methods: A smiling front view extraoral photograph of a 20-year-old woman was digitally altered simulating agenesis and its treatment, by means of: repositioning, reshaping or bleaching the canine, and gingival contour. A questionnaire was distributed to individuals of the three groups (n= 150), with a view to evaluating their degree of esthetic perception. An attractiveness scale was also used, with '0' representing unattractive and '10', very attractive. Results: In the comparative evaluation among all the photographs, the original image obtained the highest level of acceptance. Photograph 'i' (agenesis of both lateral incisors treated with reposition and reshaping of the canines) was ranked as the least attractive by the dentists, whereas the student and lay persons ranked photograph 'f' (agenesis of both lateral incisors treated with reposition of the canines, gingival contour, bleaching and reshaping) as the worst. Conclusion: The methods of treatment most accepted among the dentists and students were those that involved changes in the gingival contour, whereas among lay persons, they were those that involved only reshaping.

RESUMO Objetivo: o objetivo do presente estudo foi avaliar o grau de percepção da atratividade do sorriso por dentistas, estudantes de Odontologia e leigos, em casos de agenesia dos incisivos laterais superiores substituídos por caninos, para fechamento do espaço. Métodos: uma fotografia extrabucal frontal do sorriso de uma mulher com 20 anos de idade foi alterada simulando agenesia e seu tratamento por meio de: reposicionamento do canino, remodelação, clareamento ou contorno gengival. Um questionário foi distribuído aos indivíduos dos três grupos (n= 150), com o objetivo de avaliar o grau de percepção estética. Uma escala de atratividade também foi usada, com '0' representando pouco atraente e '10', muito atraente. Resultados: na avaliação comparativa entre as fotografias, a imagem original obteve o maior nível de aceitação. A fotografia "i" (agenesia de ambos os incisivos laterais tratada com reposição e remodelação dos caninos) foi classificada como a menos atraente pelos dentistas, enquanto os estudantes e os leigos classificaram a "f" (agenesia de ambos os incisivos laterais tratada com reposição dos caninos, contorno gengival, clareamento e remodelação) como a pior. Conclusão: os métodos de tratamento mais aceitos entre dentistas e estudantes foram aqueles que envolviam mudanças no contorno gengival, enquanto entre os leigos foram aqueles que envolviam apenas remodelação.

Anterior crossbite treatment in the primary dentition: Three case reports.

Anterior crossbite is characterized by negative horizontal overjet between the jaws, and occurs due to skeletal, functional, and/or dental imbalances. It is often found in primary and mixed dentition stages and causes severe aesthetic, functional, and psychosocial impairment. We report the facial and occlusal effects of maxillary protraction associated with rapid maxillary expansion in three young patients with primary dentition. The proposed treatment plan consisted of protraction and rapid maxillary expansion. The mechanical device chosen was the facial mask combined with a McNamara rapid palatal expander. The anterior crossbite was corrected, and significant facial and cephalometric benefits were obtained. The treatment of maxillary protraction during the deciduous dentition stage, in cases where there is good acceptance and collaboration by patients, provides excellent clinical results and constitutes a viable treatment option.

Periodontal clinical evaluation before and after surgically assisted rapid maxillary expansion.

INTRODUCTION: The surgically assisted rapid maxillary expansion is a procedure that reduces the resistance of the sutures correcting the posterior crossbite in adults. OBJECTIVE: The aim of this study was to evaluate the periodontal status of 17 adults submitted to this procedure. METHODS: The clinical attachment level (CAL), gingival recession, attached gingiva and bleeding were evaluated in maxillary first premolars and molars, central and lateral incisors of right and left sides before surgery, 5 days and 6 months after. Means, standard deviation, medians, minimum and maximum values were compared among the evaluations using the Friedman and McNemar tests. RESULTS: There was a statistically significant increase in CAL in the right central incisor, right and left premolars and right and left molars. There was a statistically significant increase in gingival recession in the right and left premolars and molars. The amount of attached gingiva significantly decreased in right premolars and right and left molars. There was increase in bleeding in most of the teeth. CONCLUSION: Results indicated that the surgically assisted rapid maxillary expansion might cause alterations in periodontal tissue.

Photoelastic analysis of stress distribution in mandibular second molar roots caused by several uprighting mechanics.

INTRODUCTION: Mandibular molar uprighting is indicated when mesial inclination of the second molars occurs because of missing first molars. There are many methodologies to perform such movement. In this study, we aimed to analyze and compare the stress distributions in different molar uprighting techniques. METHODS: Four photoelastic models were designed to evaluate different mandibular second molar uprighting techniques: a miniscrew positioned in the retromolar region, a beta-titanium alloy cantilever spring, a beta-titanium alloy wire with a T-loop spring, and an 0.018-in stainless steel archwire with an open-coil spring between the second premolar and the second molar. RESULTS: On the miniscrew test specimen, the greatest concentration of strains was observed in the cervical zone of the distal root. The cantilever spring had many strains in the cervical zone of the mesial root. On the T-loop spring test specimen, mainly the observed strains were in the apical zone of the mesial root. The open-coil spring specimen showed fringes in the cervical zone and the apical zone of the mesial root without formation of large sequences of strains. CONCLUSIONS: The miniscrew mechanical action had the least and the cantilever spring mechanical action had the greatest strain means on the roots of mandibular second molars.

Periodontal clinical evaluation before and after surgically assisted rapid maxillary expansion

ABSTRACT Introduction: The surgically assisted rapid maxillary expansion is a procedure that reduces the resistance of the sutures correcting the posterior crossbite in adults. Objective: The aim of this study was to evaluate the periodontal status of 17 adults submitted to this procedure. Methods: The clinical attachment level (CAL), gingival recession, attached gingiva and bleeding were evaluated in maxillary first premolars and molars, central and lateral incisors of right and left sides before surgery, 5 days and 6 months after. Means, standard deviation, medians, minimum and maximum values were compared among the evaluations using the Friedman and McNemar tests. Results: There was a statistically significant increase in CAL in the right central incisor, right and left premolars and right and left molars. There was a statistically significant increase in gingival recession in the right and left premolars and molars. The amount of attached gingiva significantly decreased in right premolars and right and left molars. There was increase in bleeding in most of the teeth. Conclusion: Results indicated that the surgically assisted rapid maxillary expansion might cause alterations in periodontal tissue.

RESUMO Introdução: a expansão rápida da maxila assistida cirurgicamente (ERMAC) é um procedimento que reduz a resistência das suturas, corrigindo a mordida cruzada posterior em adultos. Objetivo: o objetivo deste estudo foi avaliar o status periodontal de 17 adultos submetidos a esse procedimento. Métodos: o nível clínico de inserção (NCI), a recessão gengival, gengiva inserida e sangramento foram avaliados nos primeiros pré-molares, molares, incisivos centrais e laterais superiores dos lados direito e esquerdo antes da cirurgia, e depois de 5 dias e 6 meses. Médias, desvios-padrão, medianas, valores mínimos e máximos foram comparados entre as avaliações, usando os testes de Friedman e McNemar. Resultados: houve aumento estatisticamente significativo no NCI no incisivo central direito, pré-molares direito e esquerdo e molares direito e esquerdo. Houve aumento estatisticamente significativo na recessão gengival nos pré-molares e nos molares direito e esquerdo. A quantidade de gengiva inserida diminuiu significativamente nos pré-molares direitos e molares direitos e esquerdos. Houve aumento no sangramento na maioria dos dentes. Conclusão: os resultados indicaram que a ERMAC pode causar alterações no tecido periodontal.

Sex differences in pharyngeal airway morphology in adults with skeletal Class III malocclusion.

OBJECTIVES: To compare the pharyngeal airway dimensions in adults with skeletal Class III malocclusion and well-balanced faces, to ascertain whether sex can influence such measurements and to correlate skeletal pattern with pharyngeal dimensions. METHODOLOGY: Fifty adults were recruited and assigned to two groups: skeletal Class III (n = 25; 12 males and 13 females, mean age = 26.1 years), and skeletal Class I (n = 25; 11 males and 14 females, mean age = 26.0 years), with well-balanced faces. Pharyngeal measurements were made using cone beam computed tomography and analyzed with Dolphin Imaging software 11.5. RESULTS: Pharyngeal sagittal area, length, retroglossal area and width were statistically greater for males. Pharyngeal volume was greater for Class III patients (p = .0245), due to enlarged male dimensions. A significant but moderate correlation was observed between pharyngeal airway volume and ANB angle (r = -.4917) and effective mandibular length (Co-Gn, r = .5181). CONCLUSION: There is sexual differentiation in the pharyngeal airway morphology for Class III adults. As females present similar pharynx volume compared to a normal skeletal pattern, mandibular setback surgery should be carefully planned because of the risk of airway constriction.