BMP2 rs1005464 is associated with mandibular condyle size variation.

This study aimed to evaluate the association between single nucleotide polymorphisms (SNPs) in endochondral development-related genes and mandibular condyle shape, size, volume, and symmetry traits. Cone-beam Computed Tomographies and genomic DNA from 118 individuals were evaluated (age range: 15-66 years). Data from twelve 3D landmarks on mandibular condyles were submitted to morphometric analyses including Procrustes fit, principal component analysis, and estimation of centroid sizes and fluctuating asymmetry scores. Condylar volumes were additionally measured. Seven SNPs across BMP2, BMP4, RUNX2 and SMAD6 were genotyped. Linear models were fit to evaluate the effect of the SNPs on the mandibular condyles' quantitative traits. Only the association between BMP2 rs1005464 and centroid size remained significant after adjusting to account for the false discovery rate due to multiple testing. Individuals carrying at least one A allele for this SNP showed larger condylar size than common homozygotes GG (ß = 0.043; 95% CI: 0.014-0.071; P value = 0.028). The model including BMP2 rs1005464, age and sex of the participants explained 17% of the variation in condylar size. Shape, volume, and symmetry were not associated with the evaluated SNPs. These results suggest that BMP2 rs1005464 might be associated with variation in the mandibular condyles size.

Influence of nasal septum deviation on fluctuating asymmetries of the nasomaxillary complex: A cross-sectional study.

An important parameter in diagnostic analysis and treatment planning of different biological areas is facial symmetry, and several etiological factors have been attributed to skeletal facial asymmetry. Although causality cannot be determined, previous studies have reported a relationship between the anatomical deviation of the nasal septum and facial development. Diagnosis is critical for patients in growth stages due to the association between nasal septum deviation (NSD) and abnormal growth of the nasomaxillary complex. To understand this relationship, this study aimed to investigate the influence of nasal septum deviation on fluctuating asymmetries (FA) of the nasomaxillary complex at different stages of skeletal maturation. Another goal was to determine whether an association exists between the degrees of septal deviation severity and asymmetry of the nasomaxillary complex. This was a retrospective, cross-sectional observational study comprising 60 selected cone-beam computed tomography (CBCT) scans that were divided into four groups (n = 15) according to the degree of septal deviation and skeletal maturation: mild deviation (MD; <10°), moderate to severe deviation (MSD; ≥10°), early group (EG), and late group (LG). The angle and area of deviation were measured for the greatest NSD, and a geometric morphometric approach was used to evaluate the nasal septum (NS) shape. The morphology of the nasomaxillary complex and the presence of fluctuating asymmetries were evaluated using 23 two-dimensional landmarks on the nasomaxillary complex (nasal, lateral, and palatal regions) with Procrustes ANOVA and Mann-Whitney test. Additionally, Spearman's correlation and multivariate regression were used to correlate the NSD with asymmetries in these regions. No significant differences were observed in the Procrustes FA scores of the nasomaxillary complex between the MD-EG × MSD-EG and MD-LG × MSD-LG (p > 0.05). However, the results of the multivariate regression revealed more specific aspects of asymmetry (asymmetry component), there was a positive correlation between the NSD angle and the palatal regions (p = 0.035 and p = 0.047, middle and posterior, respectively), and the nasal septum shape and anterior palatal regions (p = 0.039). The nasal and lateral regions did not correlate with the NSD angle in the multivariate regression analysis (p > 0.05). The results of this study indicate that there were no significant differences in the fluctuating asymmetry of the nasomaxillary complex between the mild and moderate to severe nasal septum deviation groups, in both early and late skeletal maturation stages. However, a positive correlation was observed in the degree of nasal septum deviation angle and asymmetry components of the middle and posterior palatal regions, likewise between the nasal septum shape and asymmetry components of the anterior palatal region. The diagnosis of nasal septum deviation by both physicians and dentists is important, as a relationship was observed with fluctuating asymmetry component of the palatal region. This information can guide the decision of the treatment planning for these individuals, and should be considered, especially in cases of severe septum deviation, due to the great anatomical proximity of these structures.

Superimposition of maxillary digital models using the palatal rugae: Does ageing affect the reliability?

OBJECTIVES: The aim of this study was to evaluate the reliability of 3-dimensional maxillary dental changes using two methods of digital model superimposition. SETTING AND SAMPLE POPULATION: The Department of Orthodontics of Bauru Dental School, University of São Paulo and University of Michigan Craniofacial Growth Center. Fifteen subjects with normal occlusion. MATERIAL & METHODS: The sample was composed of digital study models of 15 normal occlusion subjects taken at 13 (T1), 18 (T2) and 60 years of age (T3). Using the software SlicerCMF 3.1, superimposition (registration) was conducted using 9 landmarks placed on the incisive papilla, second and third palatal rugae and 10 mm distal to the third palatal rugae. Two registration methods were compared: landmarks (LA) and regions of interest (ROI). Three-dimensional changes of landmarks on the buccal cusp tip of posterior teeth bilaterally and the incisal edge of the right central incisor were measured by three examiners. Intraclass correlation coefficients and Bland-Altman method evaluated intra- and inter-examiner agreements. RESULTS: Good or excellent intra-examiner agreement was found for T1-T2 and T2-T3 measurements using both registration methods. Inter-examiner agreements were good to excellent for T1-T2 measurements and poor to fair for most T2-T3 measurements. Mean T1-T2 differences were less than 0.5 mm for most measurements. CONCLUSION: Maxillary digital dental models of patients with normal occlusion superimposed on palatal rugae showed an adequate reliability for a 5-year interval comparison using landmarks or regions of interest. Lower than acceptable reproducibility using both superimposition methods was found for a 40-year interval comparison.

Three-dimensional dental and craniofacial manifestations in patients with late diagnosis of mucopolysaccharidosis type II: report of 2 cases.

The objective of this study was to report the clinical evaluation results and 3-dimensional (3-D) dental and craniofacial characteristics observed in 2 male patients with mucopolysaccharidosis type II. The patients were evaluated clinically (soft tissue evaluation, evaluation of occlusion, periodontal and dental examinations) and by using craniofacial computed tomography, with evaluation of 3-D images in ITK-Snap v. 2.2 (Penn Image Computing and Science Laboratory, Philadelphia, PA; http://www.itksnap.org/) and 3-D Slicer (http://www.slicer.org/) software. Mandibular 3-D volumetric label maps were built from computed tomography scans of both patients and compared through superimposition on a healthy patient's mandibular images. Clinically, the patients presented the following oral manifestations: macroglossia, total open bite and generalized diastemas, and absence of caries. Patient 1 showed dental calculus and bleeding at the gingival margin. Patient 2 showed bleeding at the gingival margin, a permanent maxillary left central incisor missing as a result of trauma, and impacted permanent mandibular left and right second molars. 3-D images showed wide arches, prominent antegonial notches, a narrow mandibular body in the region of the antegonial notches, bilateral severe condylar hypoplasia, and enlarged coronoid processes. 3-D imaging and superimpositions revealed oral and skeletal displacements, contributing to the identification of changes in the course of mucopolysaccharidosis type II in patients with a late diagnosis.

Displacement of the Mandibular Condyles Immediately after Herbst Appliance Insertion - 3D Assessment.

OBJECTIVE: To test the following two hypotheses regarding the consequences of Herbst appliance (HA) insertion: 1) a significant clockwise mandibular rotation will occur and 2) the displacement of the condyles will follow the same magnitude of the changes of overjet (OJ) and overbite (OB). METHODS: Virtual 3D surface models of 25 patients were generated from cone-beam computed tomographs taken before treatment and immediately after HA insertion. Scans were registered on the cranial base and were analyzed using point-to-point measurements, color-coded maps, and semitransparent overlays. Statistical tests included correlation and simple regression analysis. RESULTS: Pitch rotation, ranging from -2.2° to 2.2° (mean, 0.2°), was observed in clockwise and counterclockwise directions. Condylar sagittal displacement presented a positive correlation with OJ changes. Each millimeter of OJ correction resulted in an anterior condylar displacement of approximately 0.95 mm. Vertical condylar displacement correlated with OB changes and varied mostly between 2 mm and 4.5 mm. CONCLUSION: Immediately after HA insertion, no significant clockwise mandibular rotation was observed. The condyles were displaced anteriorly and inferiorly. Condylar anterior displacement and OJ correction presented a ratio close to 1:1. The vertical displacement of the condyles did not follow the same magnitude of OB changes.

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).

Color stability and fluorescence of different orthodontic esthetic archwires.

OBJECTIVE: To evaluate the color stability of six esthetic archwires at different time periods and their fluorescence. MATERIALS AND METHODS: Samples were evaluated after 7, 14, and 21 days of immersion in staining solution. Color measurements were performed by means of a spectrophotometer according to the Commission Internationale de I'Eclairage L*a*b* system, and color changes (ΔE*) and National Bureau of Standards units were computed. The fluorescence of as-received samples was evaluated by two observers and compared with that of a bovine central incisor. Statistical differences were investigated using analysis of variance and Tukey's post hoc test. RESULTS: All brands showed statistically significant color change after 21 days (ΔE* from 1.88 to 12.06). The Optis archwire (fiber-reinforced composite) presented the highest color alteration, although staining was observed only near its ends. The Trianeiro archwire (coated nickel-titanium) and the Ortho Organizers archwire (coated stainless steel) presented with less color change. The Optis archwire was the only one that presented with fluorescence similar to that of bovine teeth. CONCLUSIONS: All esthetic archwires assessed showed clinically noticeable color change after 21 days in staining solution. The optical properties of currently available esthetic archwires may not yet be ideal.

Orthodontic implants: concepts for the orthodontic practitioner.

Orthodontic implants have become a reliable method in orthodontic practice for providing temporary additional anchorage. These devices are useful to control skeletal anchorage in less compliant patients or in cases where absolute anchorage is necessary. There are a great number of advantages in this new approach which include easy insertion, decreased patient discomfort, low price, immediate loading, reduced diameter, versatility in the forces to be used, ease of cleaning, and ease of removal. However, a proper management of the screws by the practitioner is necessary in order to increase the success rate of the technique. The purpose of this paper is to update practitioners on the current concepts of orthodontic implants and orthodontic mechanics.

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.

Multidisciplinary approach to a traumatized unerupted dilacerated maxillary central incisor.

A patient with an impacted dilacerated maxillary left central incisor is presented. The 8-year-old girl also presented with protrusion of teeth and lips, posterior crossbite, anterior open bite, thumb-sucking habit, and transposition of the maxillary left lateral incisor and canine. The treatment consisted of a multidisciplinary approach, including surgery, orthodontics, endodontics, and prosthodontics. The dilacerated incisor was surgically exposed, tractioned, endodontically treated, and restored. Four premolars were extracted to correct the protrusion. The outcome was the accomplishment of a balanced and functional occlusion, resulting in a pleasant smile.

In vitro evaluation of fluoride release of orthodontic bonding adhesives.

AIM: To assess the fluoride release from adhesives used for bonding in orthodontics. METHODS: Six bonding agents were evaluated: five adhesives (Biofix, Fill Magic Orthodontic, EagleBond, Orthobond, and Transbond XT) and one resin-reinforced glass-ionomer cement (Fuji Ortho LC), the latter serving as a control. Ten samples of each adhesive were stored in containers with 5 mL of deionized distilled water at 37°C. Fluoride release was measured with an ion-specific electrode. Readings were taken periodically for a total of 33 days. On day 28, all samples were immersed in a 0.221% sodium fluoride solution for 5 minutes to assess their recharge potential. Descriptive statistics were calculated for the fluoride release rates of each material. ANOVA with multiple comparisons and the Kruskal-Wallis tests (P < .05) were used to assess differences between the groups. RESULTS: All adhesives released significant amounts of fluoride (P < .05). During the first day, Biofix released the highest amount of fluoride, followed by Fuji Ortho LC, which also showed the highest fluoride release from day 7 to day 33. The fluoride release from Biofix and Fuji Ortho LC decreased by the third day to 40% of its original value. All other adhesives maintained their fluoride release with only small fluctuations. CONCLUSION: All the materials released significant amounts of fluoride, with Biofix having the highest release in the first 3 days and Fuji Ortho LC over the total length of the experiment.

Natural changes of the maxillary first molars in adolescents with skeletal Class II malocclusion.

INTRODUCTION: The objective of this study was to evaluate natural changes in maxillary posterior alveolar height (MPAH) and axial inclination of the maxillary first molars (AIMFM) in subjects with Class II malocclusion to determine the validity of predictive equations. METHODS: Longitudinal records of 30 untreated white subjects (13 girls, 17 boys) with skeletal Class II malocclusion were collected at ages 9, 12, 14, and 16 years. They had participated in the Burlington Growth Centre study, and cephalograms were analyzed with Dentofacial Planner Plus software (version 2.0, Dentofacial Planner, Toronto, Ontario, Canada). Serial means were compared with the Bonferroni post-hoc test (P <0.05). Predictive equations were obtained and studied with the analysis of agreement. RESULTS: Gradually, means of MPAH had statistical increments with sexual dimorphism from 14 to 16 years of age. A distal mean of AIMFM was found at 9 years of age that decreased significantly during growth, with sexual dimorphism between the ages of 9 and 12 years. Changes in AIMFM varied among subjects in distinct stages. Values of MPAH were predicted with high validity at intervals of 3 years or longer, whereas estimations for AIMFM were unreliable. CONCLUSIONS: In this study group, there was significant alveolar growth, with a natural tendency to upright the distal inclination at the maxillary first molars.

Cytotoxicity of intermaxillary orthodontic elastics of different colors: an in vitro study.

OBJECTIVES: Natural latex does not fall into the category of materials known to be entirely inoffensive. The purpose of this in vitro study was to test the hypothesis that there is no difference in the cytotoxicity between elastics of different colors and those from different manufacturers. MATERIAL AND METHODS: Different latex intraoral elastics of different colors (5/16 = 7.9 mm, mean load) were compared. The sample was divided into 7 groups of 24 elastics each: Group T (TP Orthodontics, natural latex elastics, control); Groups U1, U2, U3, U4, U5 and U6 (Uniden, natural latex elastics and colored elastics, namely, green, pink, yellow, red and purple, respectively). Cytotoxicity assays were performed by using cell culture medium containing epithelioid-type cells (Hep-2 line) derived from human laryngeal carcinoma. The cytotoxicity was evaluated by using the 'dye-uptake' test, which was employed at two different moments (0 and 24 h). Data were compared by analysis of variance (ANOVA) and Tukey's test (p<0.05). RESULTS: There was statistically significant difference (p<0.05) between Group T and all other groups (U1, U2, U3, U4, U5 and U6) at 0 and 24 h. No statistically significant difference (p<0.05) was found between Groups U1 and U5, U1 and U6, U2 and U3, U2 and U4, U2 and U5, U2 and U6, U3 and U4, U3 and U5, U3 and U6, U4 and U5, U4 and U6, and U5 and U6 at 0 and 24 h. CONCLUSIONS: The TP Orthodontics elastics promoted less cell lysis compared to the Uniden elastics regardless of their color.

Transposition of a canine to the extraction site of a dilacerated maxillary central incisor.

This article describes the treatment of a girl in whom anterior trauma during the deciduous dentition had caused a dilacerated maxillary central incisor in the mixed dentition. The dilacerated central incisor was extracted, and a canine was transposed to the extraction site. Canine transposition was performed so that the lateral incisor could be maintained in its normal position. This article discusses the clinical implications of dental dilacerations on orthodontic treatment and the treatment possibilities.

Shear bond strength of brackets bonded to enamel with a self-etching primer. Effects of increasing storage time after activation.

OBJECTIVE: To evaluate bonding efficacy of activated Transbond Plus Self-Etching Primer (TPSEP) used at different time points with Transbond XT to bond metallic orthodontic brackets to bovine incisors. MATERIALS AND METHODS: The inferior incisors of 210 bovines were randomly divided into seven groups (n = 30). TPSEPs were mixed, activated, and kept activated for 30 (group 30), 21 (group 21), 15 (group 15), 7 (group 7), 3 (group 3), or 1 (group 1) days before bonding, and in one group (group 0) TPSEP was used immediately after mixed. At day zero, incisors in each group were bonded in exactly the same way. After applying TPSEP, brackets were bonded with Transbond XT, according to the manufacturer's instructions. After 24 hours, shear bond strength (SBS) tests were performed for all samples at a crosshead speed of 0.5 mm/min, and the Adhesive Remnant Index was scored. RESULTS: There were no significant differences between the SBS of groups 0, 1, 3, 7, and 15 (P > .05) However, those groups had higher SBS (P < .05) compared with groups 21 and 30. No significant difference (P > .05) was observed between groups 21 and 30. Despite the decrease in SBS for groups 21 and 30, bond strength values were still satisfactory. CONCLUSION: After activation, the TPSEP mix can be stored for a period of 15 days without losing its adhesive properties.

Mandibular permanent first molar and incisor width as predictor of mandibular canine and premolar width.

INTRODUCTION: Estimating the mesiodistal widths of unerupted permanent canines and premolars is an essential aspect of mixed dentition analysis. Several methods are used to predict tooth width. The best methods demonstrate high values of correlation and determination coefficients. In this study, we aimed to determine a linear regression equation that would predict the sum of the mesiodistal widths of mandibular permanent canines and premolars based on the sum of the widths of the 4 mandibular permanent incisors and first permanent molars. METHODS: The sample consisted of 500 dental casts, obtained from white Brazilian patients (250 male, 250 female; average ages, 13.8 and 14.4 years, respectively). Mesiodistal tooth widths were measured with an electronic digital caliper. Intraclass correlation coefficients were used to determine measurement consistencies. Paired and unpaired Student t tests were used to determine right/left side and sex differences, respectively. A paired Student t test was also used to compare the predicted and actual sums of the mandibular permanent canines and premolars. RESULTS: We found high values of correlation (r) and determination (r2) coefficients, varying from r = 0.795 to r = 0.81, and r2 = 0.599 to r2 = 0.656. These values are among the highest described in the literature for nonradiographic prediction methods. On average, there was no difference between predicted and actual widths of the mandibular permanent canines and premolars, and the standard errors of estimation were 1.49 mm for males, 1.36 mm for females, and 1.44 mm for the total sample (considering right and left sides of the mandibular arch together). CONCLUSIONS: The proposed method showed good accuracy and was easy to use, but it must be tested in other populations.

Microbiological evaluation of elastomeric chains.

OBJECTIVES: To evaluate in vitro the surface of elastomeric chains of different manufacturers to verify the presence of pathogenic microorganisms at the moment of unpacking and analyze a possible inhibitory effect of the elastomeric chain when exposed to microorganisms of the oral cavity, for example, Streptococcus mutans, Lactobacillus casei, and Candida albicans. MATERIALS AND METHODS: Elastomeric chains from Ortho-Organizers Inc, 3M Unitek, and Dental Morelli were placed in petri plates with brain heart infusion agar medium and in sterile test tubes with brain heart infusion broth. The samples were incubated at 37 degrees C and analyzed at 24 hours, 48 hours, 3 days, and 7 days. In addition, elastomeric chains from the three manufacturers were placed in dishes, inoculated with microorganisms, incubated at 37 degrees C, and analyzed after 24 and 72 hours. RESULTS: No microorganism growth was detected after all incubation periods. No inhibition zones were identified surrounding the elastomeric chain. CONCLUSIONS: The results suggest that the fabrication of elastomeric chain is in accordance with biohazard concepts. However, careful manipulation is necessary to avoid colonization of pathogenic microorganisms since the composition of the elastomeric chains analyzed do not include antimicrobial agents.

Dentofacial morphology of mouth breathing children.

The relationship between dentofacial morphology and respiration has been debated and investigated from various approaches. The aim of this study was to verify the skeletal and dental relationship of mouth and nose breathing children. Thirty-five children, 7 to 10 years of age, were submitted to orthodontic and otorhinolaryngologic evaluations and were separated into 2 groups: 15 nose breathers and 20 mouth breathers. Each subject underwent a cephalometric radiograph analysis. Statistical analysis (Mann-Whitney U test) indicated that changed mode of breathing was associated with 1) maxillo-mandibular retrusion in relation to the cranial base in the mouth breathers; 2) the SNGoGn and NSGn angles were greater in the mouth breathing group; 3) incisor inclination in both jaws and the interincisal angle were not different between groups. There was no statistically significant difference in the maxillary and mandibular molar heights between the nose breathers and mouth breathers.