Bernardo Quiroga Souki

Mouth breathing children and cephalometric pattern: does the stage of dental development matter?

OBJECTIVE To test the hypothesis that there is no difference in the cephalometric pattern between mouth breathing children with primary dentition and mixed dentition. METHODS Cephalometric measurements of 126 mouth breathing children (MB) were compared to 126 nasal breathing controls (NB). Both groups were divided into deciduous dentition (mean age 4 years, 8 months) and mixed dentition (mean age 7 years, 9 months) groups. RESULTS A statistically significant difference was observed in the dentofacial patterns of MB children compared to NB children. The total length of the mandible was smaller in MB compared to NB children. However, this difference was found only in subjects with mixed dentition. The length of the mandibular corpus is similar in MB and NB children, although older MB children with mixed dentition had significantly smaller measurements. The lower anterior facial height was higher in MB compared to NB children, but this difference was evident only in younger children with primary dentition. Mandibular plane angle, Y-axis angle and lower anterior facial height to total anterior facial height ratio were greater, and posterior facial height to total anterior facial height ratio was smaller in MB than NB children, indicating that mouth breathers had a more vertical facial growth pattern. However, no differences were found in the vertical growth pattern associated with the stage of dental development. The ANB angle was not associated with the maturational status of occlusion. Linear measurements and the gonial angle were significantly different between children with primary and mixed dentition, but such differences were associated with normal vertical growth. CONCLUSIONS The present investigation rejected the null hypothesis and showed significant cephalometric differences between primary and mixed dentition MB children. Mouth breathing children in the mixed dentition have a smaller mandible (in terms of total length and corpus length) than nasal breathers. In children with primary dentition, the lower anterior facial height is higher in MB than in NB children. There was no significant association between the stage of dental development of mouth breathing children (either in the primary or mixed dentition) and the other cephalometric patterns.

3D Mandibular Superimposition: Comparison of Regions of Reference for Voxel-Based Registration.

Introduction The aim was to evaluate three regions of reference (Björk, Modified Björk and mandibular Body) for mandibular registration testing them in a patients’ CBCT sample. Methods Mandibular 3D volumetric label maps were built from CBCTs taken before (T1) and after treatment (T2) in a sample of 16 growing subjects and labeled with eight landmarks. Registrations of T1 and T2 images relative to the different regions of reference were performed, and 3D surface models were generated. Seven mandibular dimensions were measured separately for each time-point (T1 and T2) in relation to a stable reference structure (lingual cortical of symphysis), and the T2-T1 differences were calculated. These differences were compared to differences measured between the superimposed T2 (generated from different regions of reference: Björk, Modified Björk and Mandibular Body) over T1 surface models. ICC and the Bland-Altman method tested the agreement of the changes obtained by nonsuperimposition measurements from the patients’ sample, and changes between the overlapped surfaces after registration using the different regions of reference. Results The Björk region of reference (or mask) did work properly only in 2 of 16 patients. Evaluating the two other masks (Modified Björk and Mandibular body) on patients’ scans registration, the concordance and agreement of the changes obtained from superimpositions (registered T2 over T1) compared to results obtained from non superimposed T1 and T2 separately, indicated that Mandibular Body mask displayed more consistent results. Conclusions The mandibular body mask (mandible without teeth, alveolar bone, rami and condyles) is a reliable reference for 3D regional registration.

Late diagnosis of dentoalveolar ankylosis: Impact on effectiveness and efficiency of orthodontic treatment

Dentoalveolar ankylosis is a local etiologic factor of malocclusion that can have deleterious effects on normal dental development. Therefore, it is of paramount importance to diagnose the problem as early as possible so that interception can be performed at the correct time. This case report demonstrates the consequences of late diagnosis of dentoalveolar ankylosis and discusses its effects on development of the occlusion and how it can increase orthodontic biomechanical complexity and treatment time.

Dental arch dimensional changes after adenotonsillectomy in prepubertal children.

INTRODUCTION The purposes of this study were to investigate the dental arch changes after adenotonsillectomies in prepubertal children and to compare the dental arch dimensions of mouth-breathing and nasal-breathing children. METHODS The sample included 49 prepubertal severely obstructed mouth-breathing children and 46 prepubertal nasal-breathing children. Twenty-four of the 49 mouth-breathing children had an adenotonsillectomy and composed the adenotonsillectomy subgroup. The 25 children in whom the mouth-breathing pattern was unchanged during the 1-year study period composed the control subgroup. RESULTS The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. After airway clearance, the adenotonsillectomy group showed a significant maxillary transverse width gain compared with the control subgroup. The control subgroup showed a significant deepening of the palatal height when compared with the adenotonsillectomy subgroup after 1 year. CONCLUSIONS The adenotonsillectomy subgroup had a significantly different pattern of arch development compared with the untreated controls. After adenotonsillectomy, the mouth-breathing children showed greater maxillary transverse development than did the controls. The palatal vault deepened in the untreated children. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children.

Are distinct etiologies of upper airway obstruction in mouth-breathing children associated with different cephalometric patterns?

OBJECTIVE To test the null hypothesis that mouth-breathing (MB) children by distinct obstructive tissues present a similar cephalometric pattern. METHODS The sample included 226 prepubescent children (113 MB and 113 nasal breathing (NB) controls). An ENT clinical examination, including flexible nasal endoscopy, orthodontic clinical and cephalometric examinations, was performed on the MB population. MB children were grouped into three categories, according to the obstructive tissues: 1) adenoid group (AG), 2) tonsillar group (TG), and 3) adenotonsillar group (ATG). The NB controls were matched by gender, age, sagittal dental relationship and skeletal maturation status. Lateral cephalometric radiography provided the cephalometric pattern comparisons between the MB and NB groups. RESULTS MB cephalometric measurements were significantly different from those of NB children, exception in the SNB° (P=0.056). All comparisons between the three groups of MB children with the NB children showed a significant difference. Finally, even among the three groups of MB children, a significant difference was observed in the measurements of the SNB° (P<0.036), NSGn° (P<0.028) and PFH/TAFH ratio (posterior facial height/total anterior facial height) (P<0.012). CONCLUSIONS The cephalometric pattern of MB and NB children was not similar. Cephalometric measurements of the MB group differed according to the etiology of upper airway obstruction. Children with isolated hypertrophy of the palatine tonsils presented with a mandible that was positioned more forward and upward compared to children obstructed only by the enlarged adenoid.

Is the growth pattern in mouth breathers comparable with the counterclockwise mandibular rotation of nasal breathers

INTRODUCTION The aim of this longitudinal study was to investigate mandibular rotation and angular remodeling in mouth-breathing children compared with nasal-breathing children. METHODS The sample included 55 severely obstructed mouth-breathing children (mean age, 6.1 years) and 55 nasal-breathing children (mean age, 7.3 years). The cephalograms at baseline and after 1 year were traced and measured, and superimpositions were made to determine true mandibular rotation, apparent rotation, and angular remodeling. The significance level was set at 5%. RESULTS The mouth-breathing children had a longer face cephalometric pattern compared with nasal-breathing children. No cranial deflection differences were observed. No changes in the vertical growth pattern were observed during the 1-year period in either group. There were no statistically significant differences between the groups regarding apparent rotation (mouth breathing, -0.54°, vs nasal breathing, -0.41°). In comparison with the nasal breathers, the mouth breathers showed statistically significant lower yearly rates of counterclockwise true rotation (mouth breathing, -0.60°, vs nasal breathing, -1.31°) and angular remodeling (mouth breathing, 0.06°, vs nasal breathing, 0.87°). CONCLUSIONS Mouth-breathing children had a hyperdivergent cephalometric pattern, but against all expectations, counterclockwise true mandibular and apparent rotations were the average observations. Mouth-breathing children showed less true rotation and angular remodeling than did nasal breathers; however, apparent rotations were similar.

Reliability of subjective, linear, ratio and area cephalometric measurements in assessing adenoid hypertrophy among different age groups

OBJECTIVE To test the validity of four different types of lateral cephalometric radiograph (LCR) measurements as a diagnostic test of adenoid hypertrophy in different age groups of mouth-breathing children. MATERIALS AND METHODS Eighty-six mouth-breathing children (male 54.65%, mean age 7.0 ± 2.2 years) were randomly selected from a hospital population. Adenoid obstruction of the nasopharynx was evaluated by subjective, linear, ratio, and area LCR measurements. Each measurement was compared with flexible fiberoptic endoscopy diagnosis. RESULTS Kendall correlation coefficients for agreement between tests were ≥ 0.67 and kappa scores were substantial (≥ 0.64). Higher correlation coefficients and agreement values were found in older age groups. When the sample was stratified by age, the 3- to 5-year-old age group showed lower correlation coefficients and agreement strength for subjective, linear, and ratio measurements. The sensitivity of LCR varied from 71% (ratio) to 84% (linear). The specificity varied from 83% (linear) to 97% (ratio). The positive predictive value varied from 88% (linear) to 97% (ratio). The negative predictive value varied from 70% (ratio) to 78% (linear). The validity of each measure was different among the age groups. CONCLUSIONS LCR is a valid method for measuring adenoid hypertrophy in children from 6 to 12 years old. The diagnosis of adenoid hypertrophy, based on LCR measurements, in children with primary dentition (3-5 years old) should be made with caution. The combination of linear and ratio LCR measurements is a reliable screening tool to determine the need for an ear, nose, and throat evaluation.

Simplificando a obtenção e a utilização de imagens digitais: scanners e câmeras digitais

Um dos grandes beneficios que a evolucao tecnologica proporcionou a Ortodontia foi a utilizacao das imagens digitais. O uso dessa nova tecnologia em Odontologia, e especificamente em Ortodontia, aliada a introducao da Fotografia Digital, permite aos profissionais desta area utilizar recursos, antes inimaginaveis, facilitando a elaboracao do diagnostico ortodontico, auxiliando a comunicacao entre profissionais, bem como com os pacientes, alem de ilustrar comunicacoes cientificas, em conferencias, cursos e publicacoes, sendo uma excelente ferramenta para o ensino e pesquisa. Com o objetivo de lancar mao dessa nova tecnologia, o ortodontista pode obter imagens digitais por meio da digitalizacao da documentacao ortodontica convencional composta basicamente de fotografias analogicas (em papel ou em slide), modelos de estudo e radiografias ou pela obtencao de imagens digitais com câmeras fotograficas digitais. Desta forma, o objetivo desse trabalho e esclarecer alguns conceitos basicos relacionados as imagens digitais e tentar responder as perguntas mais frequentes em relacao ao tema: Como digitalizar as minhas documentacoes ortodonticas com um scanner? Como obter imagens digitais com uma câmera fotografica digital? Que tipo de resolucao em DPI (dots per inch, ou pontos por polegada) ou em Megapixel (MP), tamanho e formato de arquivo devo utilizar para as minhas necessidades ortodonticas de rotina? A obtencao de imagens com finalidade apenas de visualizacao no monitor do computador e diferenciada daquela para outros fins, como impressao de relatorios, banners ou apresentacoes com recurso de multimidia? E por fim, qual resolucao deve ser utilizada para obter imagens digitais que serao encaminhadas para publicacoes cientificas?

Two-phase orthodontic treatment of a complex malocclusion: giving up efficiency in favor of effectiveness, quality of life, and functional rehabilitation?

The interceptive orthodontic treatment of patients with complex dentofacial abnormalities is frequently inefficient and produces less than ideal outcomes. Therefore, postponing therapy to a single-phase surgical-orthodontic approach might be considered a reasonable option. However, other relevant aspects of the patients quality of life, such as possible psychosocial problems and functional impairments, should also be considered before deciding whether to intercept a severe dentofacial malocclusion while the patient is still growing, or wait and treat later. This case report describes the nonsurgical treatment of a young patient with a severe Class III open-bite malocclusion associated with a cervical cystic lymphangioma. Despite the poor interceptive therapy prognosis, a 2-phase approach was effective. A reflection about giving up efficiency in favor of effectiveness, functional rehabilitation, and the patients quality of life is included.

Mandibular and glenoid fossa changes after bone-anchored maxillary protraction therapy in patients with UCLP: A 3-D preliminary assessment

OBJECTIVE To assess mandibular and glenoid fossa (GF) changes after bone-anchored maxillary protraction (BAMP) therapy in patients with unilateral complete cleft lip and palate (UCLP). MATERIALS AND METHODS The cleft group (CG) comprised 19 patients with (mean initial age of 11.8 years). The noncleft group (NCG) comprised 24 patients without clefts (mean initial age of 11.7 years). Both groups had Class III malocclusion and were treated with BAMP therapy for 18 and 12 months, respectively. Cone-beam computed tomography (CBCT) exams were performed before and after treatment and superimposed on the anterior cranial fossa (ACF). Mandibular rotations and three-dimensional linear displacements of the mandible and GF were quantified. A t-test corrected for multiple testing (Holm-Bonferroni method) and a paired t-test were used to compare, respectively, the CG and NCG and cleft vs noncleft sides (P < .05). RESULTS Immediately after active treatment, the GF was displaced posteriorly and laterally in both groups relative to the ACF. The overall GF changes in the CG were significantly smaller than in the NCG. Condylar displacement was similar in both groups, following a posterior and lateral direction. The gonial angle was displaced similarly posteriorly, laterally, and inferiorly in both groups. The intercondylar line rotated in opposite directions in the CG and NCG groups. In the CG, most changes of the GF and mandible were symmetrical. CONCLUSIONS Overall GF and mandibular changes after BAMP therapy were similar in patients with and without clefts. The exception was the posterior remodeling of the GF that was slightly smaller in patients with UCLP.