Sequencing of bimaxillary surgery in the correction of vertical maxillary excess: retrospective study.

The aim of this study was to evaluate the precision of bimaxillary surgery performed to correct vertical maxillary excess, when the procedure is sequenced with mandibular surgery first or maxillary surgery first. Thirty-two patients, divided into two groups, were included in this retrospective study. Group 1 comprised patients who received bimaxillary surgery following the classical sequence with repositioning of the maxilla first. Patients in group 2 received bimaxillary surgery, but the mandible was operated on first. The precision of the maxillomandibular repositioning was determined by comparison of the digital prediction and postoperative tracings superimposed on the cranial base. The data were tabulated and analyzed statistically. In this sample, both surgical sequences provided adequate clinical accuracy. The classical sequence, repositioning the maxilla first, resulted in greater accuracy for A-point and the upper incisor edge vertical position. Repositioning the mandible first allowed greater precision in the vertical position of pogonion. In conclusion, although both surgical sequences may be used, repositioning the mandible first will result in greater imprecision in relation to the predictive tracing than repositioning the maxilla first. The classical sequence resulted in greater accuracy in the vertical position of the maxilla, which is key for aesthetics.

Nasolabial changes after two different approaches for surgically assisted rapid maxillary expansion.

This retrospective study evaluated the nasolabial changes in patients who underwent surgically assisted rapid maxillary expansion (SARME) using two different approaches. Nineteen patients were included in the study, divided into two groups according to the kind of surgical approach performed: group 1 (n=9), SARME performed through the standard Le Fort I circumvestibular approach followed by the alar base cinch, and group 2 (n=10), SARME performed through a subtotal vestibular approach associated to a V-shaped incision at the maxillary midline in the labial frenulum region, without alar base cinch. Measurements of width, length, and nasal projection as well as upper lip length were taken from cone beam tomographic images obtained before surgery (T1) and 6 months postoperatively (T2). Both groups presented an increase in the alar base width postoperatively (P<0.05). The approach used in group 2 resulted in smaller changes in the alar base width as measured at the superior alar curvature (P<0.05). Nasal length and projection and upper lip length were not altered by SARME. The type of surgical approach influenced nasolabial changes, but did not eliminate increase in width of the alar base.

Effects of lateral osteotomy on surgically assisted rapid maxillary expansion.

This study aimed to assess the potential effects of two different osteotomy designs of the maxillary lateral wall on dental and skeletal changes after surgically assisted rapid maxillary expansion (SARME). Thirty adult patients were divided into two groups according to the lateral osteotomy design: group 1 (n=16) underwent lateral osteotomy performed in a horizontal straight fashion, and group 2 (n=14) underwent lateral osteotomy performed in parallel to the occlusal plane with a step at the zygomatic buttress. Cone beam computed tomography scans were obtained preoperatively (T1), immediately after expansion (T2), and 6 months after expansion (T3). Mixed analysis of variance (ANOVA) was used for the statistical analysis. The results showed no significant interaction effect between groups and time points. Therefore, maxillary expansion was effective in both groups. Statistically significant increases in all dental and skeletal measurements were observed immediately after expansion (P<0.001). Relapse of the nasal floor width, tipping of the supporting teeth, and an increase in root distance in molars occurred at T3 (P<0.05). In summary, the maxillary lateral osteotomy design did not influence the results of SARME, which occurred mainly through the inclination of maxillary segments.

Antibody response and avidity of respiratory syncytial virus-specific total IgG, IgG1, and IgG3 in young children.

Respiratory syncytial virus (RSV) is a major cause of acute respiratory disease in infants and young children. Considering that several aspects of the humoral immune response to RSV infection remain unclear, this study aimed to investigate the occurrence, levels, and avidity of total IgG, IgG1, and IgG3 antibodies against RSV in serum samples from children ≤5 years old. In addition, a possible association between antibody avidity and severity of illness was examined. The occurrence and levels of RSV-specific IgG depended on age, with infants <3 months old displaying high levels of antibodies, which were probably acquired from the mother. Children ≥24 months old also showed frequent occurrence and high levels of IgG, which was produced actively during infection. In addition, the avidity assay showed that the avidity of RSV-specific total IgG and IgG1 was lower in infants <3 months old who had acute respiratory disease than in age-matched controls. The avidity of RSV-specific IgG detected in children ≥24 months old with lower respiratory infection was lower than that in children with upper respiratory infection. These results indicate that the presence of high avidity RSV-specific IgG antibodies may lead to better protection against RSV infection in children <3 months old, who may have a lower probability of developing disease of increased severity. In addition, children ≥24 months old with RSV-specific IgG antibodies of low avidity tended to develop more severe RSV illness. These findings may be helpful in establishing vaccination schedules when a vaccine becomes available.

Prevalence and clinical aspects of respiratory syncytial virus A and B groups in children seen at Hospital de Clínicas of Uberlândia, MG, Brazil.

Respiratory syncytial virus (RSV) is well recognized as the most important pathogen causing acute respiratory disease in infants and young children, mainly in the form of bronchiolitis and pneumonia. Two major antigenic groups, A and B, have been identified; however, there is disagreement about the severity of the diseases caused by these two types. This study investigated a possible association between RSV groups and severity of disease. Reverse transcription-polymerase chain reaction was used to characterize 128 RSV nasopharyngeal specimens from children less than five years old experiencing acute respiratory disease. A total of 82 of 128 samples (64.1%) could be typed, and, of these, 78% were group A, and 22% were group B. Severity was measured by clinical evaluation associated with demographic factors: for RSV A-infected patients, 53.1% were hospitalized, whereas for RSV B patients, 27.8% were hospitalized (p = 0.07). Around 35.0% of the patients presented risk factors for severity (e.g., prematurity). For those without risk factors, the hospitalization occurred in 47.6% of patients infected with RSV A and in 18.2% infected with RSV B. There was a trend for RSV B infections to be milder than those of RSV A. Even though RSV A-infected patients, including cases without underlying condition and prematurity, were more likely to require hospitalization than those infected by RSV B, the disease severity could not to be attributed to the RSV groups.

Prevalence and clinical aspects of respiratory syncytial virus A and B groups in children seen at Hospital de Clínicas of Uberlândia, MG, Brazil

Respiratory syncytial virus (RSV) is well recognized as the most important pathogen causing acute respiratory disease in infants and young children, mainly in the form of bronchiolitis and pneumonia. Two major antigenic groups, A and B, have been identified; however, there is disagreement about the severity of the diseases caused by these two types. This study investigated a possible association between RSV groups and severity of disease. Reverse transcription-polymerase chain reaction was used to characterize 128 RSV nasopharyngeal specimens from children less than five years old experiencing acute respiratory disease. A total of 82 of 128 samples (64.1 percent) could be typed, and, of these, 78 percent were group A, and 22 percent were group B. Severity was measured by clinical evaluation associated with demographic factors: for RSV A-infected patients, 53.1 percent were hospitalized, whereas for RSV B patients, 27.8 percent were hospitalized (p = 0.07). Around 35.0 percent of the patients presented risk factors for severity (e.g., prematurity). For those without risk factors, the hospitalization occurred in 47.6 percent of patients infected with RSV A and in 18.2 percent infected with RSV B. There was a trend for RSV B infections to be milder than those of RSV A. Even though RSV A-infected patients, including cases without underlying condition and prematurity, were more likely to require hospitalization than those infected by RSV B, the disease severity could not to be attributed to the RSV groups.

Respiratory viruses in children younger than five years old with acute respiratory disease from 2001 to 2004 in Uberlândia, MG, Brazil.

The main viruses involved in acute respiratory diseases among children are: respiratory syncytial virus (RSV), influenzavirus (FLU), parainfluenzavirus (PIV), adenovirus (AdV), human rhinovirus (HRV), and the human metapneumovirus (hMPV). The purpose of the present study was to identify respiratory viruses that affected children younger than five years old in Uberlândia, Midwestern Brazil. Nasopharyngeal aspirates from 379 children attended at Hospital de Clínicas (HC/UFU), from 2001 to 2004, with acute respiratory disease, were collected and tested by immunofluorescence assay (IFA) to detect RSV, FLU A and B, PIV 1, 2, and 3 and AdV, and RT-PCR to detect HRV. RSV was detected in 26.4% (100/379) of samples, FLU A and B in 9.5% (36/379), PIV 1, 2 and 3 in 6.3% (24/379) and AdV in 3.7% (14/379). HRV were detected in 29.6% (112/379) of the negative and indeterminate samples tested by IFI. RSV, particularly among children less than six months of life, and HRV cases showed highest incidence. Negative samples by both IFA and RT-PCR might reflect the presence of other pathogens, such as hMPV, coronavirus, and bacteria. Laboratorial diagnosis constituted an essential instrument to determine the incidence of the most common viruses in respiratory infections among children in this region.