Analysis of maxillary arch expansion in growing patients treated with early Class III protocol versus RME.

Aim: To evaluate and compare the maxillary arch expansion obtained in growing patients treated with Class III early treatment protocol (the modified SEC III protocol), or rapid maxillary expansion (RME). Methods: This retrospective observational study included patients in the mixed dentition with maxillary constriction and/ or dental crowding. The first group consisted of 30 patients (11 males and 19 females, mean age 9.4 ±1.7 years) with dentoskeletal Class III malocclusion treated with the modified SEC III protocol. The second group of 30 patients (14 males and 16 females, mean age 9.3 ±1.5 years) with Class I or II malocclusion was treated with a Hyrax-type expander applied to bands on the first upper molars. For each subject, initial (T0) and post expansion (T1) digital dental casts were collected. The intermolar and intercanine widths, the arch lengths at both cusp and gingival levels, the anteroposterior length and the palatal depth were measured at T0 and T1. Results: At T1 there were statistically significant differences for 3-3 occlusal (OC) (P < 0.009), arch-length OC (P <0.030), anteroposterior arch-length (AP) (P <0.003), Depth (P <0.030) and Ap (P <0.000). No statistically significant T0-T1 changes were found between the modified SEC III and Hyrax groups except for Depth (P <0.011) with a mean difference of 2.3 mm between the two groups. Conclusions: Both bonded and banded expanders, used in the modified SEC III protocol and RME treatment respectively, produced similar changes in the upper arch. The different initial dentoskeletal malocclusions of the two sample groups were not relevant to the post-expansion arch changes.

Paediatric Orthodontics. Part 4: SEC III protocol in Class III malocclusion.

SEC III protocol: Early treatment of dentoskeletal Class III malocclusions. The early treatment of dentoskeletal Class III malocclusion is one of the more challenging situations for orthodontists, mainly for the uncertainty of stable long-term results due to the interaction of both environmental and genetic aetiological factors. Several interceptive protocols have been proposed during the past decades. The SEC III protocol includes two occlusal acrylic Splints combined with Class III elastics and chin cup. The protocol was proposed to facilitate Class III dentoskeletal correction by eliminating the intercuspation and the tongue thrust with clockwise mandibular rotation and minimal dentoalveolar compensation. The main difference with all the other appliances is the vertical control, which is crucial in difficult cases such as hyperdivergent Class III malocclusions.

Secondary alveolar bone grafting using autologous versus alloplastic material in the treatment of cleft lip and palate patients: systematic review and meta-analysis.

BACKGROUND: A systematic review assessing autologous versus alloplastic bone for secondary alveolar bone grafting in patients with cleft lip and palate was published in 2011 and included only one randomized controlled trial comparing traditional iliac bone graft to recombinant human bone morphogenetic protein-2 (rh-BMP2). OBJECTIVES: To perform a systematic review with meta-analysis on the use of secondary alveolar bone grafting (autologous bone and rh-BMP2 graft) in order to improve bone volume and height in patients with cleft lip and palate. DATA SOURCES: An electronic search was conducted via PubMed/MEDLINE, Cochrane Central Register of Controlled Trials (CONTROL) via Cochrane Library, EMBASE via Ovid, and LILAC for studies published between January 2008 and September 2018. The systematic review registration number at PROSPERO was 42018085858. ELIGIBILITY CRITERIA: Only RCTs were included. Inclusion criteria were patients with the diagnosis of unilateral cleft lip and palate older than 5 years of age, radiographic evaluation (CT and/or CBCT) of the cleft area, and at least a 6-month follow-up. MAIN OUTCOME MEASURES: Bone formation and bone height by radiographic CT evaluation (preoperatively, after 6 months and after 1 year of follow-up) and length of hospital stay were assessed. RESULTS: Four studies met strict inclusion criteria. Autologous bone graft showed statistically significant higher bone formation after 6-month follow-up (MD - 14.410; 95% CI - 22.392 to - 6.428; p = 0.000). No statistically significant difference was noted after a 1-year follow-up (MD 6.227; 95% CI - 15.967 to 28.422; p = 0.582). No statistically significant difference in bone height was noted after 6-month (MD - 18.737; 95% CI - 43.560 to 6.087; p = 0.139) and 1-year follow-up (MD - 4.401; 95% CI - 30.636 to 21.834; p = 0.742). Patients who underwent rh-BMP2 graft had a statistically significant reduced hospital stay (MD - 1.146; 95% CI - 2.147 to - 0.145; p = 0.025). LIMITATIONS: The main limitation is the high risk of bias among included studies. CONCLUSION: Autologous bone and rh-BMP2 graft showed a similar effectiveness in maxillary alveolar reconstruction in patients with unilateral cleft lip and palate assessing bone graft volume and height although rh-BMP2 graft showed a relative shorter length of hospital stay (high uncertainty level).

Influence of occlusal characteristics, food intake and oral hygiene habits on dental caries in adolescents: a cross-sectional study.

AIM: Dental caries is one of the most common oral diseases affecting children. The complex multifactorial aetiology of caries involves host (saliva composition and tooth enamel characteristics), oral microflora and substrate (oral hygiene quality and dietary habits composition). Occlusal characteristics may be also a factor in dental caries development. The aim of this aepidemiologic study was to verify the association between DMFT (Decayed, Missed, Filled Teeth) index and occlusal characteristics, dietary habits, oral hygiene habits and parents' education level in a sample of 12-year-old schoolchildren from Southern Italy. MATERIALS AND METHODS: A sample of 536 children was examined to detect dental caries status and several occlusal variables (i.e. molar relationship, overjet and overbite, presence of crossbite, scissor bite, crowding, diastemas and/or midline deviation). A questionnaire to retrieve parents' educational level, patient's dietary and oral hygiene habits was administered. The associations among these variables were assessed statistically through the ?2 test. RESULTS: A positive association was found between caries, parents' social status and some occlusal disorders. va specificato, l'abstract non può essere una caccia al tesoro. In relation to occlusal variables, crossbite (?2=3.96, P=0.04) was significantly associated to caries. A significant association was also found between the education level of mothers (?2=7.74, P<0.01) and fathers (?2=6.35, P=0.01) and the presence of caries. Dietary habits, oral hygiene and remaining occlusal characteristics were not associated with caries presence (all P>0.05). CONCLUSIONS: Of the evaluated occlusal characteristics only posterior crossbite was associated with caries prevalence. Education level of the parents was the other factor significantly associated with caries. Dietary habits, oral hygiene frequency and the remaining occlusal characteristics were not associated with dental caries.

Dentoskeletal features in mixed dentition children with displaced maxillary canines in a southern Italian population.

AIM: To analyse the prevalence and the distribution of displaced, buccal/palatal maxillary canines, and the association with sagittal and vertical skeletal relationships in a southern Italian population. MATERIALS AND METHODS: Consecutive records of patients were examined. Inclusion criteria were: age 7-12 years, 1-2 cervical vertebral maturation (CVM) stage, initial dental casts, intraoral photographs, panoramic, lateral and periapical radiographs. Subjects with at least one canine in Lindauer II, III or IV sector and/or α angle >31° were included in displaced maxillary canine (DMC) group, whereas those with both canines in sector I and α angle ≤31° were used as control group (CTR). According to canine bulges and/or x-ray examinations, DMC were then divided in palatal and buccal displaced canines (PDC/BDC). Sagittal and vertical skeletal relationships were evaluated using ANB and SN/GoMe angles. Chi-square tests were performed to compare the prevalence rates of skeletal features. RESULTS: The sample consisted of 123 children, 40 DMC and 83 CTR. The DMC group included 11 PDC and 29 BDC subjects. The M:F ratio was 1:3 in PDC and BDC, 1:1 in CTR group. The unilateral-to-bilateral ratio was 1:1 and 3:1 in PDC and BDC subjects. The most common sector combination regarding unilateral and bilateral displacements was "II" and "II,II". PDC occurred more in Class I and in hyperdivergents, whereas BDC in Class I or II and in normodivergents. CONCLUSIONS: DMC occurred more often in females than in males. BDC was more common than PDC and unilateral displacements occurred more frequently than bilateral ones. No significant correlation with skeletal features was observed.

Terahertz plasmonic excitations in Bi2Se3 topological insulator.

After the discovery of Dirac electrons in condensed matter physics, more specifically in graphene and its derivatives, their potentialities in the fields of plasmonics and photonics have been readily recognized, leading to a plethora of applications in active and tunable optical devices. Massless Dirac carriers have been further found in three-dimensional topological insulators. These exotic quantum systems have an insulating gap in the bulk and intrinsic Dirac metallic states at any surface, sustaining not only single-particle excitations but also plasmonic collective modes. In this paper we will review the plasmon excitations in different microstructures patterned on Bi2Se3 topological insulator thin films as measured by terahertz spectroscopy. We discuss the dependence of the plasmon absorption versus the microstructure shape, wavevector, and magnetic field. Finally we will discuss the topological protection of both the Dirac single-particle and plasmon excitations.

Interaction and dynamics of ionic liquids based on choline and amino acid anions.

The combination of amino acid anions with the choline cation gives origin to a new and potentially important class of organic ionic liquids that might represent a viable and bio-compatible alternative with respect to the traditional ones. We present here a detailed study of the bulk phase of the prototype system composed of the simplest amino acid (alanine) anion and the choline cation, based on ab initio and classical molecular dynamics. Theoretical findings have been validated by comparing with accurate experimental X-ray diffraction data and infrared spectra. We find that hydrogen bonding (HB) features in these systems are crucial in establishing their local geometric structure. We have also found that these HBs once formed are persistent and that the proton resides exclusively on the choline cation. In addition, we show that a classical force field description for this particular ionic liquid can be accurately performed by using a slightly modified version of the generalized AMBER force field.

Upper and lower arch changes after Mixed Palatal Expansion protocol.

AIM: The aim of this study was to evaluate upper and lower dental changes after Mixed Palatal Expansion (MPE) treatment in growing patients with posterior single or bilateral crossbite and mild-to-moderate crowding, as compared to untreated growing subjects by dental cast analysis. MATERIALS AND METHODS: A group of 24 patients (18 girls, 6 boys) was treated with Hyrax-type device and compared with an untreated matched control group at T0 (8.6 yrs. ± 2) and at T1 (10 yrs. ± 2) using dental casts. The dental cast analysis was performed on four dental bilateral landmarks, on upper and lower casts; also upper and lower arch depths were measured. The groups were compared using independent sample t-test to estimate dental changes in upper and lower arches. RESULTS: The MPE group showed significant upper and lower arch changes when compared with the control group. Upper intermolar, interpremolar-2nd, interpremolar-1st (P<0.001) and intercanine widths (P<0.05) showed considerable changes in the treated group, while mandibular intermolar (P<0.001), interpremolar-1st (P<0.05) and intercanine widths (P<0.01) were slightly greater in the MPE group when compared with the control group. CONCLUSION: The changes in transverse upper and lower arch dimensions were significant, when compared with those seen in the control group.

Dento-skeletal effects of mixed palatal expansion evaluated by postero-anterior cephalometric analysis.

AIM: The aim of this study was to evaluate the dento-skeletal effects of mixed palatal expansion (MPE) on growing patients with a uni- or bilateral posterior crossbite and mild-to-moderate crowding as compared to untreated growing individuals using postero- anterior (PA) cephalometric analysis. MATERIALS AND METHODS: A group of 24 patients (18 girls and 6 boys) treated with a Hyrax- type device was compared to an untreated matched control group at T0 (8.6 yrs ± 2.01) and T1 (10 yrs ± 2.00) using PA cephalograms. The cephalometric analysis included eight bilateral skeletal and dental landmarks. The groups were compared using independent sample t-test to estimate dento-skeletal effects on PA cephalograms. RESULTS: The treated group showed significant changes for the maxillary width (P<0.001) and upper molar width (P<0.001) when compared to those of the control group. CONCLUSION: MPE may effectively increase transverse dimensions and correct posterior crossbites.

Cytokines and VEGF induction in orthodontic movement in animal models.

Orthodontics is a branch of dentistry that aims at the resolution of dental malocclusions. The specialist carries out the treatment using intraoral or extraoral orthodontic appliances that require forces of a given load level to obtain a tooth movement in a certain direction in dental arches. Orthodontic tooth movement is dependent on efficient remodeling of periodontal ligament and alveolar bone, correlated with several biological and mechanical responses of the tissues surrounding the teeth. A periodontal ligament placed under pressure will result in bone resorption whereas a periodontal ligament under tension results in bone formation. In the primary stage of the application of orthodontic forces, an acute inflammation occurs in periodontium. Several proinflammatory cytokines are produced by immune-competent cells migrating by means of dilated capillaries. In this paper we summarize, also through the utilization of animal models, the role of some of these molecules, namely, interleukin-1ß and vascular endothelial growth factor, that are some proliferation markers of osteoclasts and osteoblasts, and the macrophage colony stimulating factor.