Claudia Trindade Mattos

Bone mineral density

OBJECTIVE To verify whether bone mineral density (BMD) of cortical bone, trabecular bone, and total bone influence the primary stability of orthodontic miniscrews and to verify whether there is a correlation between the measurement of BMD by cone-beam computed tomography (CBCT) and central dual-energy x-ray absorptiometry (DEXA). MATERIALS AND METHODS Twenty bovine bone sections were extracted from the pubic and iliac bones from regions with cortical thicknesses of approximately 1 mm. The BMD of the total bone block was evaluated using two methods: CBCT and DEXA. The BMD of cortical, trabecular, and total bone in the region of interest (ROI) were also evaluated by CBCT. After scanning the bone blocks, 20 self-drilling miniscrews (INP®) 1.4 mm in diameter and 6 mm long were inserted into them. The peak implant insertion torque (IT) was registered. After this, the pull-out test (PS) was performed and the maximum force registered. The Pearson correlation test was applied to verify the correlations between variables. RESULTS The BMD of the total bone block verified by CBCT and DEXA showed a positive and strong correlation (r  =  0.866, P  =  .000). The BMD of the ROI for cortical bone influenced the IT (r  =  0.518, P  =  .40) and the PS of miniscrews (r  =  0.713, P  =  .001, Table 2). However, the total bone BMD (verified by CBCT and DEXA) and trabecular bone BMD presented weak and not statistically significant correlations with primary stability. CONCLUSIONS There was a positive correlation between total bone block BMD measured by DEXA and CBCT. The cortical BMD influenced the IT and PS.

Effects of orthognathic surgery on oropharyngeal airway: a meta-analysis.

Oropharyngeal changes caused by orthognathic surgery have been a concern because the sleep quality of patients may be enhanced or worsened by these changes. The purpose of this meta-analysis was to identify, review and compare scientific literature about changes in airway in adult patients undergoing orthognathic surgery to correct anteroposterior osseous discrepancies. An electronic search of four databases was carried out up to July 2010, with supplemental hand searching of the references of the retrieved articles. Quality assessment of the included articles was carried out. Data were extracted and a meta-analysis was performed. Heterogeneity was assessed amongst the studies and results were presented in forest plots. 49 studies met the inclusion criteria. Only studies with moderate or high methodological soundness were included in the review. Moderate evidence was found to support a significant decrease in the oropharyngeal airway in mandibular setback surgery, a milder decrease in bimaxillary surgery to correct Class III and an increase in maxillomandibular advancement surgery. Evidence is lacking on airway volume changes after orthognathic surgery.

Is the airway volume being correctly analyzed

INTRODUCTION The aim of the study was to determine the most accurate threshold value for airway volume quantification based on specific experimental conditions. METHODS Ten scans from the airway prototype were obtained by using cone-beam computed tomography. The volume from each scan was measured with 8 values (25, 50, 70, 71, 72, 73, 74, and 75) of the threshold tool from the Dolphin software (Dolphin Imaging and Management Solutions, Chatsworth, Calif). The gold standard method used was the actual volume of the airway prototype, which was compared with the different threshold values. An intraclass correlation coefficient test was applied to evaluate the intraexaminer calibration and verify differences among the airway volumes measured in all cone-beam computed tomography scans. Analysis of variance with the Tukey post-hoc test was used to compare differences among the measurements with different threshold values with the gold standard. RESULTS The intraexaminer reliability was confirmed by the intraclass correlation coefficient, which was ≥0.99. The intraclass correlation coefficient used to verify the differences among the airway volume measurements in all cone-beam computed tomography scans was ≥0.98, showing that they were comparable. Analysis of variance and the Tukey post-hoc test showed that the volumes measured with the threshold values of the 25 and 50 filters had statistically significant differences from the gold standard. However, volumes measured with the threshold values of the 70, 71, 72, 73, 74, and 75 showed no statistically significant differences from the gold standard and among them. CONCLUSIONS In our study for the cone-beam machine and the acquisition parameters used, the threshold value of the 73 used in Dolphin 3D software was the most accurate to measure airway volume, but the threshold values of the 70, 71, 72, 74, and 75 had no statistically significant differences compared with the gold standard, showing they are also reliable.

Reliability of upper airway linear, area, and volumetric measurements in cone-beam computed tomography.

INTRODUCTION Our objective was to assess the intraexaminer and interexaminer reliabilities of upper airway linear, area, and volumetric measurements in cone-beam computed tomography. METHODS Cone-beam computed tomography scans of 12 subjects were randomly selected from a pool of 132 orthodontic patients. An undergraduate student, an orthodontist, and a dental radiologist independently made linear, area, and volumetric measurements. Linear anteroposterior and transversal measurements, cross-sectional area, sagittal area, minimum axial area, and volume measurements were made. The intraclass correlation coefficient (ICC) was used to assess intraexaminer and interexaminer reliabilities, and measurement errors were assessed. Agreement was further assessed with the Bland-Altman method and 95% limits of agreement. RESULTS Overall, the ICC values indicated good reliability for the measurements assessed. The ICC values were greater than 0.9 (excellent) for 93% of intraexaminer and 73% of interexaminer assessments. Transversal width measurements and cross-sectional area at the level of the vallecula, however, had only moderate reliability (minimum ICC, 0.63), large 95% limits of agreement, and the greatest mean measurement errors (as high as 16% and 13% of the mean measurements, respectively). Linear anteroposterior measurements; cross-sectional areas at the levels of the palatal plane, soft palate, and tongue; and sagittal area and volume were reliable measurements, with a minimum ICC of 0.93 and more restricted limits of agreement. CONCLUSIONS Based on these results, airway assessments by examiners with different backgrounds might have reliable anteroposterior linear measurements; cross-sectional areas at the levels of the palatal plane, soft palate, and tongue; and sagittal area and volume. The unreliable measurements were linear width, cross-sectional area at the level of the vallecula, and minimum axial area.

Mother-to-child transmission of Streptococcus mutans: A systematic review and meta-analysis

OBJECTIVES A systematic review was performed with the aim of determining whether there is scientific evidence of the transmission of Streptococcus mutans from mother to child. DATA The eligibility criteria, based on the PECO strategy, were the following: observational human studies whose subjects were mother and child pairs (P) contaminated by S. mutans (E); comparison according to the presence or absence of S. mutans (C); and whether there is transmission (O). The qualitative analysis was performed by assessing the risk of bias of the included studies, while quantitative synthesis was performed through comprehensive Meta-Analysis software (p<0.05). SOURCES Two reviewers performed the database search of studies published between January 1950 and May 2014. The strategy included observational studies that assessed the vertical transmission of S. mutans from mothers to children through analyzing genetic strains. STUDY SELECTION It was found 166 non-duplicated studies. However, after reviewing the articles in full and applying the eligibility criteria, 36 papers were selected for qualitative analysis and 19 for quantitative analysis. The cumulative meta-analysis demonstrated vertical transmission of S. mutans from mother to child (p<0.001). CONCLUSIONS The present systematic review and meta-analysis demonstrated evidence of vertical transmission of S. mutans from mother to child because there was an association between S. mutans n mothers and their respective children. CLINICAL SIGNIFICANCE The knowledge of the S. mutans strains is important because the virulence of the microorganisms is varied; also, the virulence affects the dental caries evolution rate, being more or less aggressive.

Coating stability and surface characteristics of esthetic orthodontic coated archwires

OBJECTIVE To evaluate the coating thickness of four brands of as-received esthetic coated rectangular archwires and their surface characteristics and coating stability after 21 days of oral exposure compared to those of conventional stainless steel (SS) and nickel titanium (NiTi) ones. MATERIALS AND METHODS The labial surface of the selected archwires was observed with a stereoscope and in a scanning electron microscope, and surface roughness was assessed with an atomic force microscope. The coating thickness of as-received wires and the percentage of coating lost on the labial surface of retrieved wires were measured using Image Pro Plus 4.5 software. RESULTS All groups showed an average coating thickness of less than 0.002 inches. After oral exposure, archwires from two groups lost all coating on the labial surface. On average, 28.71% and 72.90% of the coating was lost in each of the other two groups, and the surface roughness of the remaining coating was higher than postclinical control wires. CONCLUSION Coated archwires had a low esthetic value as they presented a nondurable coating. The remaining coating showed a severe deterioration and a greater surface roughness than postclinical control counterparts (conventional SS and NiTi wires).

Does cortical thickness influence the primary stability of miniscrews? A systematic review and meta-analysis

OBJECTIVE To investigate whether there is evidence to support the association between cortical thickness (CtTh) and the primary stability of mini-implants (MI). MATERIALS AND METHODS A search was performed including articles published until September 2013. The inclusion criteria comprised observational clinical studies conducted in patients who received monocortical MI for orthodontic anchorage and in vivo or ex vivo experimental studies performed to evaluate the primary stability of MI, studies that evaluated the association between CtTh and MI primary stability, CtTh measurement performed numerically, and MI primary stability evaluated by implant stability quotient value, Periotest value , pull-out strength, or insertion torque. Studies conducted exclusively in artificial bone or finite elements were excluded. RESULTS Abstract and title reading identified 15 possible articles to be included. After reading the complete text, three were excluded. One article was found by hand searching and another excluded for an overlapping sample. Finally, 12 articles were selected. A positive correlation was found between primary stability and CtTh when studies that evaluated primary stability through PS were grouped (r  =  .409) and when studies that evaluated stability in humans were grouped (r  =  .338). CONCLUSIONS There is a positive association between MI primary stability and CtTh of the receptor site. However, there is still a lack of well-designed clinical trials.

Long-term prognosis of tooth autotransplantation: a systematic review and meta-analysis

The aim of this study was to systematically review the prognosis of autotransplanted teeth followed up for a period of 6 years or more. A literature search was conducted in five databases and the eligibility criteria were established. The outcomes evaluated were the survival rate, percentage of abnormal mobility, pulpal conditions, and percentage of root resorption. The searches identified 1848 articles, and after evaluation against the eligibility criteria, six were included. Data related to outcome measures were extracted from the studies and a meta-analysis was performed. Survival rates ranged from 75.3% to 91% and the meta-analysis showed an effect size of 81% (P<0.0001). The percentage ankylosis ranged from 4.2% to 18.2% and the effect size was 4.8% (P<0.0001). Root resorption percentages ranged from 3% to 10% and the effect size was equal to 4% (P<0.0001). It was not possible to perform a meta-analysis of data on pulpal conditions and percentage of teeth with abnormal mobility. The results of this study showed the survival rate to be excellent, considering the observation period. The rates of ankylosis and root resorption, despite their low values, influence the prognosis of transplanted teeth.

Long-term dental and skeletal changes in patients submitted to surgically assisted rapid maxillary expansion: A meta-analysis

OBJECTIVE This meta-analysis evaluated long-term dental and skeletal changes in patients submitted to surgically assisted rapid maxillary expansion. METHODS A search was performed in electronic databases. Human clinical trials with patients submitted to surgically assisted rapid maxillary expansion with a follow-up of at least 1 year after expansion were selected. A methodological quality scoring process was used. A meta-analysis was performed to compare measurements of skeletal and dental structures. RESULTS Three hundred sixty-five titles and abstracts were read. Ultimately 10 studies met the inclusion criteria. The 3 articles ranked as presenting low methodological quality were excluded. Three measurements could be compared and 3 time periods were used to assess changes. CONCLUSIONS There is moderate evidence to conclude that maxillary alveolar width and intercanine and intermolar width have a long-term significant increase as a result of surgically assisted rapid maxillary expansion. A significant relapse is expected in the intercanine width after expansion.

Upper airway dimensions in patients undergoing orthognathic surgery: a systematic review and meta-analysis.

The objective of this systematic review was to evaluate the effect of different types of orthognathic surgery on the dimensions of the upper airways assessed using three-dimensional images. An electronic search was performed in Cochrane Library, Medline, Scopus, VHL, Web of Science, and the System for Information on Grey Literature in Europe, ending January 2015. Inclusion criteria encompassed clinical studies in humans, patient age >15 years, patients submitted to maxillary or mandibular advancement or setback surgery, isolated or in combination, and presentation of airway measures, specifically volume and/or minimum cross-sectional area (CSA), obtained from computed tomography or magnetic resonance imaging. Additional searches were conducted on the references of included articles and in the NLM catalogue. An assessment of the risk of bias was performed. A total of 1180 studies were retrieved, of which 28 met the eligibility criteria; one was later excluded as it presented a high risk of bias. A meta-analysis was performed. There is moderate evidence to conclude that the upper airway minimum CSA increases significantly (124.13 mm(2)) after maxillomandibular advancement (MMA); the total volume increases significantly after MMA (7416.10mm(3)) and decreases significantly after maxillary advancement+mandibular setback (-1552.90 mm(3)) and isolated mandibular setback (-1894.65 mm(3)).