A preliminary investigation into the impact of soft tissue augmentation-based periodontal phenotype modification therapy for patients exhibiting class III decompensation.

BACKGROUND: Patients with skeletal angle Class III malocclusion usually have inadequate hard and soft tissue volume at the mandibular anterior teeth. The labial proclination at the teeth may lead to gingival recession. The purpose of this study was to explore whether periodontal phenotype modification therapy with soft tissue augmentation (PhMT-s) can prevent gingival recession in these patients. METHODS: Four patients with skeletal Class III malocclusion and a thin periodontal phenotype underwent surgical-orthodontic treatment. Prior to tooth movement, they underwent a minimally invasive vestibular incision with subperiosteal tunnel access combined with autogenous connective tissue grafts for periodontal phenotype modification with soft tissue augmentation (PhMT-s). The labial gingival thickness of the anterior mandibular teeth was measured at three distinct levels: at the cementoenamel junction (GT0), 3 mm apical to the CEJ (GT3), and 6 mm apical to the CEJ (GT6). These measurements were taken at baseline, three months following PhMT-s, and after tooth decompensation. Additionally, a biopsy sample was obtained from the PhMT-s site of one patient. All sections were subsequently stained using hematoxylin and eosin, Masson trichrome, Sirius Red, and immunohistochemistry. RESULTS: The thickness of the labial gingiva was increased about 0.42 to 2.00 mm after PhMT-s. At the end of pre-orthognathic surgical orthodontic treatment, the thickness of the labial gingiva was increased about - 0.14 to 1.32 mm compared to the baseline and no gingival recession occurred after the pre-orthognathic surgical orthodontic treatment. The histologic results demonstrated that the grafts obtained from the PhMT-s site exhibited increased deposition of collagen fibers. Moreover, the proportion of type III collagen increased and the grafts displayed significantly reduced positive expression of CD31 and OCN. CONCLUSIONS: PhMT-s increased the thickness of the soft tissue, stabilizing the gingival margin for teeth exhibiting a thin periodontal phenotype and undergoing labial movement. This is attributed to the increased deposition of collagen fibers.

Short-term effects of a modified Alt-RAMEC protocol for early treatment of Class III malocclusion: a controlled study.

OBJECTIVES: To assess the effects of a modified alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol in combination with facemask (FM) in Class III growing patients. SETTING AND SAMPLE POPULATION: Thirty one Class III patients (17 males, 14 females) were treated with a modified Alt-RAMEC/FM protocol at the Department of Orthodontics of the University of Florence. MATERIAL AND METHODS: All patients were evaluated at the beginning (T1, mean age 6.4 ± 0.8 years) and at the end of orthopedic therapy (T2, mean age 8.1 ± 0.9 years), and they were compared to a matched sample of 31 Class III patients (16 males and 15 females) treated with rapid maxillary expansion and facemask (RME/FM) and to a matched control group of 21 subjects (9 males and 12 females) with untreated Class III malocclusion. The three groups were compared with anova with Benjamini-Hochberg correction for multiple tests. RESULTS: Both the Alt-RAMEC/FM and the RME/FM protocols showed significantly favorable effects leading to correction of the Class III malocclusion. The Alt-RAMEC/FM protocol produced a more effective advancement of the maxilla (SNA +1.2°) and greater intermaxillary changes (ANB +1.7°) vs. the RME/FM protocol. No significant differences were recorded as for mandibular skeletal changes and vertical skeletal relationships. CONCLUSION: The Alt-RAMEC/FM protocol induced more favorable skeletal short-term effects compared with RME/FM therapy in Class III growing patients.

Long-term evaluation of condylar positional and volumetric parameters and skeletal stability in Class III bimaxillary orthognathic surgery patients.

This retrospective study examined long-term (4-5 years) condylar positional and volumetric changes and skeletal stability after bimaxillary orthognathic surgery in skeletal Class III patients. Pre-surgical (T0: 0.9 ± 1.1 months) and post-surgical (T1: 0.6 ± 0.7 months; T2: 12.8 ± 3.1 months; T3: 56.5 ± 6.5 months) cone beam computed tomography (CBCT) images of 22 patients were obtained. CBCT multiplanar reformation (MPR) images were generated, and three-dimensional (3D) condylar models were constructed and superimposed to compare changes in condylar volume from pre- to postoperative. Condylar position in the sagittal and coronal planes altered immediately after surgery; however at long-term follow-up, the condyles had returned to their pre-surgical position. The condyles remained slightly inwardly rotated at short-term (-2.6°, 95% confidence interval -3.5° to -1.7°) and long-term (-1.9°, 95% confidence interval -2.8° to -1.0°) follow-up. Changes in condylar volume were insignificant after surgery. Condylar positional changes had no effect on skeletal stability. However, patients with an increased face height prior to surgery and more retrusive jaw position postoperatively were more prone to condylar resorption. Surgical changes remained stable 4-5 years after surgery. In conclusion, condylar position changed insignificantly following surgical correction in Class III patients provided that the correct surgical technique was employed.

Associations between skeletal discrepancies, breathing pattern, and upper airway obstruction in Class III malocclusions.

OBJECTIVE: To verify the associations between sagittal and vertical skeletal discrepancies, changes in upper airways, and breathing pattern in children and adolescents with Angle Class III and Class III subdivision malocclusions. METHODS: Eighty-five children and adolescents with a mean age of 9.5 ± 1.74 years were selected. Cephalometry assessed the sagittal relationship (AO-BO measurement), facial types (Ricketts VERT index), nasopharynx, and oropharynx. An otorhinolaryngologist analyzed the breathing pattern and upper airway obstruction during anamnesis, physical examination, anterior rhinoscopy, and nasofibroscopy. Medical records were also reviewed. For statistical analysis, ordinary one-way ANOVA, Kruskal-Wallis (Tukey's post-hoc), unpaired t-test, Pearson's correlation, chi-square, and Fisher's exact tests (p < 0.05) were used. RESULTS: The nasopharyngeal cephalometric dimension and pharyngeal tonsil hypertrophy were associated, whereas the oropharyngeal cephalometric dimension and palatine tonsils hypertrophy were not. Sagittal discrepancies were associated with septum deviation, while facial type was associated with inferior turbinate and palatine tonsils hypertrophy. However, facial type was not associated with breathing pattern, septum deviation, and pharyngeal tonsils hypertrophy. CONCLUSIONS: Sagittal discrepancies and type of malocclusion were not associated with breathing pattern and changes in upper airways, except for the severity of septum deviation and Class III malocclusions, which were associated with large sagittal discrepancies. Although the facial types analyzed presented signs of airway obstruction, the highest prevalence of inferior turbinate and palatine tonsils hypertrophy were found in patients with dolichofacial type.

[Effects of orthopedic treatment on temporomandibular joint in class III patients with anterior crossbite: a literature review]. / Efectos del tratamiento ortopédico en la articulación temporomandibular en pacientes clase III con mordida cruzada anterior: una revisión de literatura.

Objective: The study aimed to evaluate the effects of orthopedic treatment on the temporomandibular joint (TMJ) in class III patients with anterior crossbite. Materials and Method: Four databases were reviewed until December 2022 (Scopus, PubMed, Embase, and Science Direct). Two independent reviewers selected studies reporting TMJ changes and the presence of TMJ dysfunction in Class III patients with anterior crossbite who received orthopedic treatment. The methodological quality of the studies was analyzed using the PRISMA checklist. Results: Twelve articles were selected for the study after a detailed search according to the selection criteria. Post-treatment studies demonstrated a low prevalence of TMJ pain after using the Delaire face mask, chin rest, modified Jasper Jumper, and fixed reverse Twin block. After treatment with reverse Twin block, an increase in condylar volume and joint spaces (p<0.001) was observed, followed by a significant decrease in posterosuperior joint spaces (p<0.001). Conclusions: Not enough evidence has been found to determine the presence of TMD or TMJ changes after using orthopedic devices for anterior crossbite correction.

Effects of maxillary expansion and protraction on pharyngeal airway dimensions in relation to changes in head posture and hyoid position : A retrospective cohort study.

PURPOSE: To assess changes in pharyngeal airway dimensions, head posture and hyoid position after maxillary expansion and face mask (FM) treatment compared to untreated class III patients. METHODS: This study examined 24 class III patients (10 girls, 14 boys, mean age: 10.97 ± 0.88 years) treated with expansion and a petit-type FM appliance and 24 untreated class III patients (16 girls, 8 boys, mean age: 10.50 ± 1.06 years). Pre- and posttreatment cephalometric radiographs were digitally analysed. Parametric data were analysed with paired and independent-samples t­tests, nonparametric data were analysed with Wilcoxon signed-rank and Mann-Whitney U tests. Spearman's correlation analysis was used to examine the relationship between dental/skeletal treatment changes and those of craniocervical postural position, pharyngeal airway dimension and hyoid position. RESULTS: With respect to the hypopharyngeal airway dimension, the hypopharyngeal sagittal length (CV3'-LPW), velar angle (HRL/U-PNS) and velar length (U-PNS) significantly increased in the treatment group. All the parameters describing head posture and those describing the distances of the hyoid bone to the HRL changed significantly after treatment, but these changes were not significantly different from the control group. In the treatment group, there also occurred a significant increase in the sagittal growth of the maxilla (SNA, Co­A, Na-Perp A, Wits), vertical growth of the maxillomandibular complex (SN-GoGN, N­ANS, N­Me), counterclockwise rotation of the maxilla (SN-PP) and overjet, while a clockwise rotation (y-axis) and a nonsignificant inhibition of the sagittal growth (Co-Gn) of the mandible were observed. The treatment induced increases of hypopharyngeal sagittal length (CV3'-LPW), soft palate thickness and anteroposterior movement of hyoid bone (H-CV3) demonstrated a positive correlation with changes of craniocervical angles (NSL/OPT, NSL/CVT) and a negative correlation with craniohorizontal angles (OPT/HOR, CVT/HOR). The change of the anteroposterior movement of hyoid bone (H-CV3) was also positively correlated with oropharyngeal sagittal length (CV2'-MPW), the hypopharyngeal sagittal length (CV3'-LPW) and the minimal dimension of the pharyngeal airway space (PASmin). CONCLUSION: While expansion and FM treatment did not affect the head posture and hyoid bone position, positive effects were observed in the hypopharyngeal airway region.

Influence of facial components in class III malocclusion esthetic perception of orthodontists, patients, and laypersons.

PURPOSE: The aim of the present study was to investigate the influence of different facial components (face length, lip volume, nose size, and cheekbone contour) on the perception of facial attractiveness of patients with Angle class III malocclusion in different categories of responders (orthodontists, laypersons, patients) with two-dimensional (2D) and three-dimensional (3D) simulations. METHODS: An ideal standard 3D face was manipulated to create a class III facial malocclusion. Four facial components were modified (face length, lip volume, nose size and cheekbone contour) and the resulting simulations were used to obtain 2D figures and 3D videos, which were evaluated in a survey by orthodontists, patients, and laypersons. RESULTS: No significant differences were detected between the 2D figures and 3D video simulations. Good correspondence was shown between the three categories of responders for the most and the least attractive faces. Smaller lips and bigger nose, regardless to the vertical dimension (short or long face), were found to be the least attractive features with agreement of all respondents. CONCLUSION: Regarding class III facial attractiveness perception, the sum of all facial features and not the alteration of a single component alone seems to play a key role in the perception of facial attractiveness. The 2D or 3D perspective did not play a significant role in perception and the analyzed categories of responders did not show significant differences when perceiving facial attractiveness of the utilized simulations.

Bimaxillary Distalization with Skeletal Anchorage for Management of Severe Skeletal Class III Open Bite Malocclusion.

Adult patients with severe vertical growth pattern, skeletal class III malocclusion and open bite anteriorly are difficult orthodontic cases to treat. An orthognathic surgical treatment plan may benefit adult patients with such types of complex malocclusions, however in certain cases, the patient's medical history may contraindicate the surgical treatment plan. A male patient aged 17 years presented with a prognathic mandible, Angle's class III malocclusion on a class III skeletal base with proclination in upper incisors, retroclination of lower incisors, and reduced facial convexity. Patient gave history of asthma and complex cardiac diseases including arrhythmia, irregular heartbeat, and pacemaker. This case report describes a non-surgical approach of distalization of mandibular and maxillary arches performed with the help of miniplates to achieve an improvement in the facial balance without surgery.

Relapse patterns of two-jaw surgical correction in patients with skeletal Class III malocclusion and different vertical facial types.

The aim of this study was to evaluate postoperative relapse after the surgical correction of skeletal Class III deformities of various facial patterns as a guide to surgical planning. A retrospective cohort study of 90 consecutive patients with skeletal Class III malocclusion who underwent bimaxillary surgery was performed. The surgical outcomes and postoperative stability were compared. The primary predictor variable was vertical facial type, which was classified into three groups according to the Frankfort mandibular plane angle (FMA). The primary outcome of angular and linear measurements was obtained using serial cone beam computed tomography scans obtained at time points of preoperative, 1 week after surgery, and orthodontic debonding. No significant difference in skeletal relapse was observed in patients with the different vertical facial types. The mandible displayed a forward and upward relapse in all three groups postoperatively. The patients with a low FMA exhibited a more consistent mandibular relapse pattern than those with a normal or high FMA. These findings suggest that bimaxillary surgery is clinically stable for mandibular prognathism regardless of the vertical facial pattern. However, 1-1.5 mm of overcorrection in the mandible setback should be considered in patients with a low FMA, because of the greater facial depth and consistent forward and upward mandibular relapse pattern.

Three-dimensional changes in the location of soft tissue landmarks following bimaxillary orthognathic surgery.

OBJECTIVES: We sought to determine the amount of three-dimensional (3D) movement of soft tissue landmarks in patients who underwent bimaxillary orthognathic surgery. MATERIALS AND METHODS: We recruited 28 patients (11 women and 17 men), who had received one-piece Le Fort I osteotomy with maxillary advancement and impaction, and bilateral sagittal split ramus osteotomy for mandibular setback. The 3D images were acquired 1-7 days before surgery and at least 6 months after surgery using stereophotogrammetry. We recorded 50 coordinate measurements and correlated the movements between soft and hard tissues. Paired samples t­test, independent samples t­test, and Pearson's correlation analysis were used for statistical analysis. RESULTS: Patients' ages ranged from 17-31 years (mean 20.4 ± 3.0 years). The mean advancement and impaction of the maxilla was 4.7 ± 1.2 and 2.2 ± 1.0 mm, respectively. The mean setback of the mandible was 4.2 ± 1.6 mm. Menton (Me) moved significantly closer to the midsagittal plane, and the bilateral alare (Al) and alar curvature (Ac) moved laterally. In addition, pronasale (Prn), bilateral Al, Ac, subnasale (Sn), subspinale (Ss), labiale superior (Ls), sublabiale (Sl), pogonion (Pog), and Me moved upwards. The bilateral cheek bone (Cbp), Al, Ac, Prn, Sn, Ss, Ls, and stomion (Sto) moved forward. Li, Sl, Pog, and Me moved backward. Interestingly, poor correlation was found between soft tissue landmarks and hard tissue movements. CONCLUSION: We observed 3D coordinate changes in several soft tissue landmarks in the middle and lower thirds of the face. The results of this study may be useful for estimating postoperative changes in similar patients.

Orthopaedic and orthodontic treatment with hyrax, Class III elastics on mandibular miniplates, maxillary mini-implants in a Class III adolescent: A case report.

BACKGROUND: The treatment of Skeletal Class III malocclusion continues to be considered as one of the biggest challenges in orthodontics as the success of its correction is largely unpredictable. Early diagnosis and treatment are highly recommended to eliminate primary etiological factors and prevent an increase in severity of the existing malocclusion. However, if the diagnosis is delayed until adulthood, treatment becomes restricted to orthognathic surgery due to limited or no remaining growth potential left. The inherent risks involved with the surgical procedures often preclude the patients from opting for it, thus leaving the orthodontist with no option but to perform possible compensatory treatments to improve facial aesthetics and restore functional occlusion. OBJECTIVE: To report the case of a 15-year old boy (adolescent) with Skeletal Class III malocclusion, a concave facial profile with an anterior crossbite and no incisor visibility during smile. METHODS: Intra-oral skeletally anchored maxillary protraction (I-SAMP) and mini-implants associated with fixed appliance to aid in the correction of the skeletal bases and subsequently relieve the dental crowding. RESULTS: After 36 months of treatment, functional normal occlusion with a Class I molar and canine relation was achieved. The consequential increase in upper lip thickness and decrease in lower lip fullness alongwith an increased exposure of maxillary incisors during smile resulted in a significant improvement of the patient's facial profile and an aesthetically pleasing smile.

Maxillary protraction in patients with unilateral cleft lip and palate : Evaluation of soft and hard tissues using the Alt-RAMEC protocol.

PURPOSE: The aim of this study was to evaluate the hard and soft tissue effects and differences of the Alt-RAMEC protocol to the facemask and conventional facemask protocols in patients with unilateral cleft lip and palate. METHODS: This prospective study was carried out with 30 patients with unilateral cleft lip and palate with skeletal and dental class III malocclusions who were referred to a university department of orthodontics. The patients were evaluated with the cervical vertebral maturation method and divided into two groups, each consisting of 15 patients. The patients in group I (mean age 10.00 ± 0.73 years) were treated according to conventional facemask protocol, and the patients in group II (mean age 10.07 ± 2.43 years) were treated according to the Alt-RAMEC protocol before facemask application. Lateral cephalometric radiographs were evaluated by using the Dolphin Imaging Software version 11.7. The skeletal, dentoalveolar and soft tissue differences and treatment times were evaluated. RESULTS: Group II demonstrated a 5.73° increase in SNA, which was statistically significant, while this increase was 3.13° in group I (p < 0.001). Results for Co­A and A­PTV showed a significant increase for group II only (group I: 1.02 mm, 1.06 mm, group II: 3.02 mm, 2.21 mm; p < 0.05 and p < 0.01, respectively). In addition, group II presented significant increase for the values of ANB, N­A-Pg, SN/MP, Wits, U1-SN, U1-L1, U1-PTV, U1-FHP, U6-PTV, U6-FHP, overjet, Ss-PTV, UL-PTV and UL­S line (p < 0.001). The treatment mean times were 7.3 months in group I and 4.7 months in group II (p < 0.01). CONCLUSION: Applying the facemask after having followed the Alt-RAMEC protocol induced more skeletal, dentoalveolar and soft tissue changes in comparison to the conventional facemask protocol in patients with unilateral cleft lip and palate.

Effectiveness of Tongue Crib Combination Treating Severe Skeletal Angle Class III Malocclusion in Mixed Dentition.

OBJECTIVE: To evaluate the treatment effects of tongue crib combination for treating severe skeletal Angle class III malocclusion in mixed dentition by X-ray cephalometric analysis. MATERIALS AND METHODS: A sample of 22 patients with severe skeletal Angle class III malocclusion of deficiency maxilla and overgrown mandible in mixed dentition was prospectively collected and equally divided into two groups. The patients (males 6 and females 5; mean age 8.35 ± 1.6 years) in the study group were treated with tongue crib combination, and the untreated patients (females 5, males 6; mean age 8.12 ± 1.3 years) served as the control group. X-ray cephalometric films were measured before and after treatment for comparing the change of occlusion, maxilla, mandible, and soft tissue. A paired t-test was used by SPSS 21.0 statistical software. The intragroup data were compared by using the Wilcoxon test, and intergroup data were compared by using the Mann-Whitney U test (p < 0.05). RESULTS: In the study group, all patients got a favorable facial profile. Anterior and posterior teeth crossbite and upper and lower first molars relationships were improved. In cephalometric measurement, significant changes were noted in the maxillary skeletal component. The significant forward growth of the maxilla exhibited in a statistical increase of SNA, ANS-PNS, Wits appraisal, p < 0.05. The mandible revealed slightly posterior rotation by no significant decrease in SNB and no change Co-Gn. After 1-year of retention, the changes of the teeth showed self-correction and facial profile improved further. Regarding vertical changes, maintenance of growth was shown a small non-significant increase of FMA, N-Me, and ANS-Me. There is a significant difference from those in the control group (p < 0.05). CONCLUSION: Tongue crib combination is an effective device for the patients in the growing period with skeletal Angle class III malocclusion by improving the maxillary growth and limiting the mandibular growth. HOW TO CITE THIS ARTICLE: Zhao W, Chen Y, Kyung H-M, et al. Effectiveness of Tongue Crib Combination Treating Severe Skeletal Angle Class III Malocclusion in Mixed Dentition. Int J Clin Pediatr Dent 2020;13(6):668-676.

Periodontal soft- and hard-tissue changes after augmented corticotomy in Chinese adult patients with skeletal Angle Class III malocclusion: A non-randomized controlled trial.

BACKGROUND: To investigate soft- and hard-tissue changes after augmented corticotomy in Chinese adult patients with skeletal Angle Class III malocclusion. METHODS: This non-randomized controlled trial included 357 anterior teeth from 30 Chinese adult patients with skeletal Angle Class III malocclusion for whom the proposed treatment was augmented corticotomy. Jaws receiving surgery were allocated to a test group (S, surgical group, n = 47) and jaws not receiving surgery were allocated to a control group (NS, non-surgical group, n = 13). Changes in the periodontal biotype, width of the keratinized gingiva (WKG), and labial and lingual horizontal bone thicknesses (BTs) were compared 6 months after surgery by univariate and multivariate analyses. RESULTS: After adjustment for confounding variables, average gains of 0.473 mm in the WKG and 0.649 mm in the labial BT were found in the S group relative to the NS group (P <0.05). The odds of transition from a thin periodontal biotype to a thick biotype in the S group were about 230 times those in the NS group, and the odds of the reverse biotype transition in the NS group were about 83 times those in the S group (P <0.05). CONCLUSIONS: Within the limitations of the present study, augmented corticotomy is a promising approach to improve insufficient periodontal soft and hard tissues in Chinese adult patients with skeletal Angle Class III malocclusion.

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.

Premaxillary-maxillary suture development in the first trimester : An ultrasound study.

PURPOSE: Our study was designed to investigate premaxillary-maxillary suture growth in fetuses from the first trimester of pregnancy using the B­ultrasound technique in order to determine the suture fusion time. METHODS: We selected 169 healthy Han singleton pregnancies as subjects. All subjects received routine pregnancy tests and were divided into three groups based on the gestational age of the fetus: group 1, the 11th gestational week; group 2, the 12th gestational week; and group 3, the 13th gestational week. Fetal biometric measurements were recorded during consecutive prenatal ultrasonographic examinations. These measurements included nuchal translucency thickness, crown-rump length, and premaxillary-maxillary length. Intergroup comparisons were performed using analysis of variance (ANOVA). RESULTS: The premaxillary-maxillary suture grows gradually and its measured length at the 11th, 12th and 13th week was 0.54 cm, 0.65 cm, and 0.74 cm, respectively. We observed a significant linear correlation between the premaxillary-maxillary length and the week of gestation in the first trimester. The growth rate of the maxilla at the 11th, the 12th and the 13th week are significantly different with a descending order of growth rates being week 12, week 11 and week 13, with the 12th week rate being the most rapid. CONCLUSION: The premaxillary and maxillary growth at 11 and 12 gestational weeks in the first trimester steadily accelerated, peaking at the 12th week. The rate of growth slows down after week 12 which may be associated with the fusion of the premaxillary-maxillary suture.

Tratamento da classe III com disjunção maxilar e tração reversa da maxila: relato de caso clínico / Class III treatment weth maxillary disjunction and reverse maxillary traction: clinical case report

Objetivo: A má oclusão classe III de Angle se caracteriza por protrusão mandibular, retrusão maxilar ou pela combinação de ambas. Além de prejudicar a estética facial do paciente, essa má oclusão pode causar alterações funcionais e respiratórias. Uma das alternativas de tratamento para esses casos é o uso da máscara de Petit e do aparelho disjuntor de Hyrax. Este estudo tem como objetivo avaliar por meio da cefalometria ortodôntica se o tratamento com expansão maxilar em conjunto com a tração reversa da maxila diminuem os agravos estéticos e funcionais do paciente Classe III. Relato de caso: o relato de caso descrito no presente trabalho é sobre uma paciente que foi submetida a esse tratamento, sendo descrito por meio de análises cefalométricas, exames radiográficos, fotos intrabucais e achados clínicos. Considerações finais: A verificação dos resultados obtidos após o término do tratamento mostrou que a paciente teve uma boa adesão ao uso desses aparelhos e obteve resultados satisfatórios na sua função mastigatória, na sua oclusão e na sua estética facial e dentária.(AU)

Objective: Angle class III malocclusion is characterized by mandibular protrusion, maxillary retrusion or a combination of both. In addition to impairing the patient's facial aesthetics, this malocclusion can cause functional and respiratory changes. One of the treatment alternatives for these cases is the use of the Petit mask and the Hyrax breaker device. This study aims to evaluate, through orthodontic cephalometry, whether the treatment with maxillary expansion in conjunction with the reverse traction of the maxilla reduces the aesthetic and functional problems of Class III patients. Case report: the case report described in the present work is about a patient who underwent this treatment, being described through cephalometric analysis, radiographic examinations, intraoral photos and clinical findings. Final considerations: The verification of the results obtained after the end of the treatment showed that the patient had a good adherence to the use of these devices and obtained satisfactory results in her masticatory function, in her occlusion and in her facial and dental aesthetics.(AU)

Compensation in Class III Malocclusions: Analysis of Tooth Crown Inclination on Digital Dental Casts / Compensação da Má Oclusão de Classe III: Análise da Inclinação das Coroas dos Dentes em Modelos Digitais

The objective of this study was to evaluate the tooth crown inclination in maxillary and mandibular arches in Class III malocclusion individuals, to identify the presence and magnitude of compensation. The study was conducted on 46 plaster casts of individuals with Class III malocclusion, of both genders (25 males and 21 females), with mean age 21 years and 1 month, with indication for compensatory orthodontic treatment. The dental casts models were scanned and the tooth crown inclinations were measured and compared with standard values by the independent t test. All tests considered a significance level of 5% (p<0.05). According to the results there was extensive variation in tooth inclination in Class III malocclusions. Values distribution for incisors highlighted the significant concentration of maxillary incisors in the area of positive values, compared with a very expressive concentration of mandibular incisors in the area of negative values. Compared with normal standards, in Class III malocclusions, the maxillary posterior teeth exhibited smaller palatal inclination than normal, while the mandibular incisors and second molars presented greater lingual inclination. It was concluded that the analysis of inclinations of all crowns of both dental arches in Class III malocclusions, compared with normal standards, evidenced the presence of natural compensation for maxillary posterior teeth, with reduced palatal inclination, as well as increased lingual inclination in mandibular incisors. The parameters of compensation naturally present in Class III malocclusions described, especially in lower incisors, would help clinicians when compensatory treatment is considered. (AU)

O objetivo deste estudo foi avaliar a inclinação das coroas dentárias nas arcadas superior e inferior em indivíduos com má oclusão de Classe III, para identificar a presença e a magnitude da compensação. O estudo foi realizado em 46 modelos de gesso de indivíduos com má oclusão de Classe III, de ambos os sexos (25 homens e 21 mulheres), com média de idade de 21 anos e 1 mês, com indicação de tratamento ortodôntico compensatório. Os modelos de gesso foram digitalizados e as inclinações da coroa dos dentes foram medidas e comparadas com os valores de normalidade pelo teste t independente. Todos os testes estatísticos adotaram um nível de significância de 5% (p <0,05). De acordo com os resultados, houve grande variação na inclinação dentária nas más oclusões de Classe III. A distribuição dos valores para os incisivos destacou a concentração significativa de incisivos superiores na área de valores positivos, em comparação com uma concentração muito expressiva de incisivos inferiores na área de valores negativos. Comparados aos padrões de normalidade, nas más oclusões de Classe III, os dentes posteriores superiores exibiram inclinação palatina menor que o normal, enquanto os incisivos e segundos molares inferiores apresentaram inclinação lingual maior. Concluiu-se que a análise das inclinações de todas as coroas de ambas as arcadas dentárias nas más oclusões de Classe III, comparadas aos padrões de normalidade, evidenciou a presença de compensação natural para os dentes posteriores superiores, com diminuição da inclinação palatina, bem como aumento da inclinação lingual dos incisivos inferiores. Os parâmetros de compensação naturalmente presentes nas más oclusões de Classe III descritos, especialmente nos incisivos inferiores, podem auxiliar o clínico quando o tratamento compensatório é considerado. (AU)

Two-phase treatment of patients with crossbite and tendency toward skeletal Class III malocclusion.

Angle Class III malocclusion is characterized by an inadequate anteroposterior dental relationship which may or may not be accompanied by skeletal changes. In general, patients are distressed by a significantly compromised facial aspect which, when associated with a deficient middle third, encourages patients to seek treatment. This article reports a two-phase treatment carried out in a female patient aged six years and six months with a tendency towards a Class III skeletal pattern. This case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO). It is representative of the category with Discrepancy Index (DI) equal or greater than 10, and fulfills part of the requirements for obtaining BBO Diploma.

From conventional to self-ligating bracket systems: is it possible to aggregate the experience with the former to the use of the latter?

INTRODUCTION: Orthodontics, just as any other science, has undergone advances in technology that aim at improving treatment efficacy with a view to reducing treatment time, providing patients with comfort, and achieving the expected, yet hardly attained long-term stability. The current advances in orthodontic technology seem to represent a period of transition between conventional brackets (with elastic modules) and self-ligating brackets systems. Scientific evidence does not always confirm the clear clinical advantages of the self-ligating system, particularly with regard to reduced time required for alignment and leveling (a relatively simple protocol), greater comfort for patients, and higher chances of performing treatment without extractions - even though the number of extractions is more closely related to patient's facial morphological pattern, regardless of the technique of choice. Orthodontics has recently and brilliantly used bracket individualization in compensatory treatment with a view to improving treatment efficacy with lower biological costs and reduced treatment time. OBJECTIVE: This paper aims at presenting a well-defined protocol employed to produce a better treatment performance during this period of technological transition. It explores the advantages of each system, particularly with regards to reduced treatment time and increased compensatory tooth movement in adult patients. It particularly addresses compensable Class III malocclusions, comparing the self-ligating brackets system, in which greater expansive and protrusive tooth movement (maxillary arch) is expected, with Capelozza Prescription III conventional brackets, in which maintaining the original form of the arch (mandibular arch) with as little changes as possible is key to yield the desired results.