The patient presented in this case report is a 10-year-old boy with hyperdivergent skeletal Class II associated with familial genetic agenesis of the second premolars. The treatment plan chosen was to close the spaces of agenesis using a bimaxillary appliance fixed buccally. The advantages and disadvantages of this treatment option were discussed. The result was stable and made it possible to avoid an implant-prosthetic solution, which would undoubtedly have been more restrictive over time.
This study aimed to prepare a glass ionomer (GI) cement reinforced with silver-hydroxyapatite-silica (Ag/HA/Si) hybrid nanoparticles and assess its compressive strength and fluoride release profile.
In this in vitro, experimental study, 60 cylindrical specimens were fabricated with 4 mm diameter and 6 mm height in 6 groups (n = 10) using BracePaste composite, GC Fuji II LC pure RMGI, and RMGI reinforced with 0.1wt%, 0.5wt%, 1wt%, and 2wt% Ag/HA/Si hybrid nanoparticles. The specimens were subjected to compressive force in a universal testing machine to measure their compressive strength (MPa). To assess their fluoride release profile, discs with 3 mm diameter and 2 mm thickness were fabricated from Fuji II LC pure resin-modified glass ionomer (RMGI), and RMGI with 0.1wt%, 0.5wt%, 1wt%, and 2wt% hybrid nanoparticles, and the concentration of released fluoride was measured by a digital ion-selective electrode. Data were analysed by ANOVA and Scheffe test (alpha = 0.05).
The compressive strength was 114.14 MPa for BracePaste composite, and 97.14, 97.84, 100.65, 109.5, and 89.33 MPa for GI groups with 0%, 0.1%, 0.5%, 1% and 2% hybrid nanoparticles, respectively, with no significant difference among them (P = 0.665). Addition of 1% (0.21 ± 0.07 μg/mL, P = 0.029) and 2% (0.45 ± 0.22 μg/mL, P = 0.000) hybrid nanoparticles to RMGI significantly increased the amount of released fluoride, compared with the control group (0.09 ± 0.03 μg/mL).
Addition of Ag/HA/Si hybrid nanoparticles to RMGI in the tested concentrations had no significant effect on its compressive strength but addition of 1wt% and 2wt% concentrations of Ag/HA/Si hybrid nanoparticles increased its fluoride release potential.
This systematic review aimed to assess the biological response at tissue, cellular, and molecular levels following Piezocision™ surgery, and its efficacy in accelerating orthodontic tooth movement.
A systematic review of the literature was conducted across 4 databases following the PRISMA guidelines up to May 2022. Prospective controlled animal studies involving healthy animals under active orthodontic treatment assisted by corticotomy performed with a piezotome (Piezocision™) published in the English language without time restrictions were included. The article selection, data extraction and risk of bias assessment (SYRCLE tool) were performed by two independent blinded review authors.
Out of 738 articles screened, 10 studies were included with various level of bias. Biological responses were categorized into tissue, cellular, and molecular levels. Tissue-level changes included a global decrease in bone mineral content post-Piezocision™. At the cellular level, increased bone turnover activity was noted. Molecularly, elevated RANKL and OPG expression, along with increased TRAP+ and cytokines, were observed after Piezocision™. Studies confirmed Piezocision's efficacy, reporting 1.35 to 3.26 times faster tooth movements, peaking between the 3rd and 50th day post-surgery. Biological responses were transient, reversible, and proportional to surgical insult, with reactivation possible through a second Piezocision™.
After Piezocision™ surgery, a transient and reversible biological response was described at the tissue, cellular and molecular levels, which induced faster orthodontic tooth movements. This biological response could be re-activated by an additional Piezocision™ and is proportional to the surgical injury.
Prospero CRD42022303237.
To assess the allele rs 1143634 in IL-1β and rs1800587 in IL-1α in patients for orthodontically induced external apical root resorption (EARR).
Intra-oral periapical radiograph (IOPA) of maxillary incisors of 142 Patients were evaluated for resorption at two time points; before the start of fixed mechanotherapy (T1) and after one year of treatment (T2). The individuals with root resorption < 2 mm were categorized as a control group (group 1; n = 90), and resorption > 2 mm were categorized as case group (group 2; n = 52). Buccal swabs of all patients were taken and DNA could be isolated in 95 out of 142 samples (group 1 {n = 58}, group 2 {n = 37}), which were then screened for the selected two polymorphic targets to determine the nucleotide status of these targets. Tetra-primer ARMS PCR reactions were carried out using all 4 primers for each polymorphism.
rs11800587 was not associated with risk of EARR in any inheritance model. Chi-square test for association of alleles with EARR revealed that rs1143634 was associated with the risk of EARR in an allelic model in such a way that A allele of this SNP increased the risk of EARR 4 folds [OR = 4.375; P = 0.016]. However, the adjusted level of significance using the Holm-Bonferroni method for rs1143634 was P < 0.010 for A and G comparison rendering the results non-significant.
SNP rs1143634 and SNP rs11800587 were not associated with risk of EARR in any inheritance model.
The aim of this study was to assess the interaction between a 0.019 × 0.025-inch (″) stainless steel archwire and two types of passive self-ligating brackets with the same slot height (0.022″) and different slot depths (0.028″ and 0.026″, and to measure the archwire/slot play as well as to compare the torque expression with archwire torsions of 12°, 24°, and 36°.
An experimental device was developed along with a universal testing machine to measure torque expression in two types of brackets with 0.028″ and 0.026″ slot depths. Analysis of variance (ANOVA) and Tukey's test were performed to identify the differences between groups.
The 0.026″ slot bracket presented greater archwire/slot play when compared to the 0.028″ bracket. Torque expression with torsions of 24° and 36° were significantly higher in the 0.028″ depth brackets when compared to the 0.026″ depth brackets.
The 0.022″ × 0.026″ passive self-ligating brackets attached with a 0.019″ × 0.025″ stainless steel archwire provided no greater torque control when compared to 0.022″ × 0.028″ passive self-ligating brackets.
Treatment of skeletal class II growing patients often requires the use of functional appliances, aimed at promoting mandibular advancement. Among these, Herbst appliance is recommended for its effectiveness, efficiency, and reduced need for compliance. Despite its skeletal favourable effects, well-known dental compensations can occur, especially when the appliance is not used close to the pubertal peak: upper incisors retroclination, lower incisors proclination, upper molars distalization and lower molars mesialization could reduce the overjet needed for a proper mandibular advancement. To counteract these unfavourable effects skeletal anchorage could be crucial.
The aim of this case report is to describe and evaluate the effects of using a skeletally anchored Herbst appliance in an 18-year-old (CVM5) male patient with skeletal Class II malocclusion and a convex profile.
The treatment started with a tooth-bone-borne palatal expansion, then the upper arch was bonded with pre-adjusted ceramic brackets. After 2 months, a Manni Telescopic Herbst (MTH) supported by 4 miniscrews (two in the maxilla and two in the mandible) was applied. To avoid anchorage loss, TADs were connected with elastic chains to the arches. Nine months later, the Herbst was removed, the lower teeth were bonded and the patient wore class 2 elastics to stabilise the occlusion.
After 24 months the treatment goal was achieved with a considerable improvement of the profile and a clinically significant mandibular advancement (Pogonion moved forward 7 mm). A one-year follow-up lateral X-rays showed a good stability of the result.
Fluoride-Amorphous Calcium Phosphate and Biomimetic Nano-Hydroxyapatite for Enamel Remineralization; An In-Vitro Study of Surface Microhardness and Composition.
Ninety-six extracted human premolars with sound buccal surface were divided using a randomization computer-generating software into four groups; Group I (control) sound untreated enamel, Group II (demineralized) demineralized to create white spot lesions, Group III (biom-n-HA) demineralized and then treated with biomimetic nanohydroxyapatite cream, and Group IV (F-ACP) demineralized and then treated using Fluoride-Amorphous Calcium Phosphate varnish. Each group was divided into two subgroups; subgroup “A” evaluated for mineral content using energy dispersive x-ray spectroscopy (EDX) and for surface microhardness using the Vickers microhardness test and Subgroup “B” evaluated for white spot lesion depth using a polarized light microscope (PLM).
The highest microhardness (VHN) was found in the (F-ACP) group (mean = 428.61 ± 54.43) and then in the (Biom-n-HA) group (mean = 408.11 ± 70.16) followed by the (Control) group (mean = 402.13 ± 53.40) with no significant difference between them and finally in the significantly different (Demineralized) group (mean = 256.99 ± 45.83). The weight percentage of Ca (30.29 ± 1.04 and 33.44 ± 1.07) and Ca/P ratio (1.87 ± 0.06 and 2.03 ± 0.05) were significantly different between Group III and Group IV respectively. PLM measurements in Group II (198.83 μm), Group III (60.17 μm), and Group IV (26.33 μm) were significantly different.
Both the (Biom-n-HA) cream and the (F-ACP) varnish showed promising results for enamel remineralization. The increased enamel surface microhardness was consistent with the mineral content and the changes in the birefringence.
Mandibular canine impaction is infrequent in dental eruption anomalies and treatment is very challenging. The aim of this multicenter retrospective panoramic study in Latin America was to evaluate panoramic radiographic imaging characteristics of mandibular canine impaction (impaction area, mandibular base contact, transmigration, impaction height and sex) and their associations.
This cross-sectional study evaluated 212 digital panoramic radiographs from three radiological centres in Tingo Maria (Peru), Bogota and Tunja (Colombia). The study included children of both sexes with impacted mandibular canines. Mandibular alpha angle, contact with mandibular basal bone (MBB), impacted sector according to 10 sectors with an adaptation of the Ericson and Kurol method, presence of transmigration and the impacted height were measured and the relationship among these measures was analyzed. Fisher's exact test, Chi-square and binary logistic regression were used. (P < 0.05).
The mandibular canine impaction showed contact with the MBB (32.08%), dental transmigration (36.79%), mainly located at an apical (40.09%) and sub-apical (36.79%) level. Transmigration mainly occurred in sectors 6 (33.30%) and 10 (25.60%) (P < 0.001). It was found that for each year of increase in age, the possibility of contact with the MBB decreased (β = 0.89, P = 0.010), and as the alpha angle increased by one degree the probability of contact with the MBB decreased (β = 0.97, P = 0.001) and the probability of transmigration increased (β = 1.05, P < 0.001).
One third of the impacted canines were in contact with the MBB, while another third presented dental transmigration and were mainly located apically and subapically of the incisor roots. These imaging features should be taken into account when planning orthodontic treatment.
Two-phase treatment for children with Class II malocclusion with several functional appliances is still performed by many orthodontists, while the Activator and the Bionator appliances are two of the most popular ones. Aim of this study was to compare the skeletal and dentoalveolar effects of treatment with these two appliances.
Class II children treated with Activator or Bionator in the first phase, followed by a phase of fixed appliances were included. Skeletal and dentoalveolar parameters were assessed from lateral cephalograms and analysed with linear regressions at 5%.
A total of 89 patients (mean age 10.0 years; 47% female) were included. During the first phase, Bionator increased less the SNB (difference in mean treatment-induced changes [MD] –0.7°; 95% confidence interval [CI] –1.3 to –0.2°; P = 0.01) and decreased less the ANB angle (MD 0.6°; 95% CI 0 to 1.1°; P = 0.03) compared to Activator. Activator slightly increased the facial axis and Bionator reduced it (MD –1.6°; 95% CI –2.3 to –0.8°; P < 0.001). Compared to Activator, the Bionator retroclined more the upper incisors (MD –2.4°; 95% CI –4.6 to –0.2°; P = 0.03) and increased more the interincisal angle (MD 2.9°; 95% CI 0.5 to 5.4°; P = 0.02). After the second phase (6.2 years after baseline), the only differences were a reduced facial axis (MD –1.3°; 95% CI –2.2 to –0.3°; P = 0.008) and an increased maxillary rotation (MD 0.9°; 95% CI 0 to 1.8°; P = 0.04) with Bionator compared to Activator.
Similar dentoalveolar effects were seen overall with two-phase treatment with either appliance, with Bionator being associated with more vertical increase compared to Activator.
We aimed to compare alveolar morphometry in young adults with agenesis of the upper lateral incisor versus the side without agenesis and versus matched controls.
In this observational retrospective study, cone beam computed tomography scans were obtained of 36 upper hemiarches from young adults aged 15 to 30 years. The hemiarches were distributed into three groups: group 1: 12 upper hemiarches presenting agenesis of the upper lateral incisor; group 2: 12 upper hemiarches from the opposite side without agenesis of the upper lateral incisor (control group 1); and group 3: 12 upper hemiarches without agenesis of the upper lateral incisor matched for age and sex with respect to the affected group (control group 2). A trained and calibrated investigator performed all the alveolar measurements at two different times, including sagittal, coronal and axial slices of each hemiarch. Paired Student's t-tests, Chi-square and repeated measures ANOVA with Bonferroni correction were used, (P < 0.05).
Apical mesial evaluation of group 1 (4.22 ± 1.19 mm) was significantly lower (P < 0.001) than that of groups 2 (6.72 ± 1.17 mm) and 3 (7.58 ± 1.67 mm). Apical distal evaluation also showed differences (P < 0.001) among the three groups, with the dimension being smaller in group 1 with agenesis (4.53 ± 1.14 mm), followed by group 2 without agenesis (6.23 ± 1.55 mm) and the healthy control group 3 (7.73 ± 1.71 mm).
Lateral incisor agenesis significantly reduces the alveolar dimensions of the affected area. In cases of unilateral agenesis, the unaffected side also shows sequelae, with decreased dimensions compared to cases without agenesis. This condition should be taken into account when making therapeutic decisions regarding rehabilitation with implants or canine replacement.
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