Electrical stimulation therapy and rotary jet-spinning scaffold to treat bone defects.

The combination of electrical stimulation (ES) and bone tissue engineering (BTE) has been successful in treatments of bone regeneration. This study evaluated the effects of ES combined with PCL + ß-TCP 5% scaffolds obtained by rotary jet spinning (RJS) in the regeneration of bone defects in the calvaria of Wistar rats. We used 120 animals with induced bone defects divided into 4 groups (n = 30): (C) without treatment; (S) with PCL+ ß-TCP 5% scaffold; (ES) treated with ES (10 µA/5 min); (ES + S) with PCL + ß-TCP 5% scaffold. The ES occurred twice a week during the entire experimental period. Cell viability (in vitro: Days 3 and 7) and histomorphometric, histochemical, and immunohistochemical (in vivo; Days 30, 60, and 90) analysis were performed. In vitro, ES + S increased cell viability after Day 7 of incubation. In vivo, it was observed modulation of inflammatory cells in ES therapy, which also promoted blood vessels proliferation, and increase of collagen. Moreover, ES therapy played a role in osteogenesis by decreasing ligand kappa B nuclear factor-TNFSF11 (RANKL), increasing alkaline phosphatase (ALP), and decreasing the tartarate-resistant acid phosphatase. The combination of ES with RJS scaffolds may be a promising strategy for bone defects regeneration, since the therapy controlled inflammation, favored blood vessels proliferation, and osteogenesis, which are important processes in bone remodeling.

Impact of Dental Aesthetic Index characteristics on the severity levels of malocclusion in a non-White population.

INTRODUCTION: This study evaluated the impact of the esthetic and occlusal characteristics of the Dental Aesthetic Index (DAI) on the need for orthodontic treatment in a non-White population. METHODS: A cross-sectional study was conducted with 1296 non-White adolescents aged 12 years. DAI was the outcome variable (DAI 1 and 2 and DAI 3 and 4). The independent variables were categorized on the basis of the occlusal esthetic characteristics evaluated by DAI (tooth absence, crowding, spacing, midline diastema, maxillary misalignment, mandibular misalignment, maxillary anterior overjet, mandibular overjet, anterior open bite, and anteroposterior molar relationship). Simple logistic regression models were adjusted for the outcome, and the raw odds ratios were estimated. Variables with a P value of <0.20 for individual analyses were tested in a multiple logistic regression model, with P ≤0.05 remaining. RESULTS: A total of 1296 adolescents (764 girls and 532 boys) were evaluated; 1067 (82.3%) had DAI 1 or 2 (minor to a moderate need for orthodontic treatment), and 229 (17.7%) had DAI 3 or 4 (defined need for orthodontic treatment). The results showed that adolescents with diastema, maxillary irregularity, mandibular irregularity, mandibular overjet, anterior open bite, and the altered molar relationship had 5.34, 2.36, 2.63, 3.56, 8.73, and 5.16 times more likelihood to have DAI 3 or 4 (P ≤0.05), respectively. CONCLUSIONS: Diastema, maxillary and mandibular misalignment, mandibular overjet, anterior open bite, and anteroposterior molar relationship were the characteristics that influenced the determination of the need for orthodontic treatment in a non-White population using the DAI index.

Can text messages encourage flossing among orthodontic patients?

OBJECTIVES: To assess the extent to which text messages on WhatsApp play a role in patient awareness of the importance of proper oral hygiene and flossing on a daily basis and to test the null hypothesis that daily text messages do not influence the flossing habits of orthodontics patients. MATERIALS AND METHODS: Forty-four patients wearing fixed orthodontic appliances with a mean age of 14.3 years participated in the study. Patients (male and female) were randomly assigned to two groups (n = 22): group 1, text messages sent via WhatsApp daily during the study period, and group 2 (control), no text messages received. Plaque index, gingival bleeding index, and halitosis were assessed at baseline and after 30 days. The results were analyzed and subjected to normality test, McNemar test, Fisher exact test, Mann-Whitney test, and Wilcoxon signed-rank test. RESULTS: There was a significant influence on flossing habits (P < .05) and a significant reduction in plaque and gingival bleeding indices in group 1 (P < .05). Group 1 had a significant reduction in halitosis (P < .05). CONCLUSIONS: Daily text messages seem to influence patient awareness of the importance of proper oral hygiene and flossing. The null hypothesis was rejected because those patients who received text messages every day changed their flossing habits.

Oral and maxillofacial outcomes in children with microcephaly associated with the congenital Zika syndrome.

INTRODUCTION: The objective of this study is to assess the oral and maxillofacial characteristics of microcephalic children associated with congenital Zika syndrome (CZS). METHODS: A cross-sectional, observational study was carried out with 61 patients with microcephaly/CZS born between June 2015 and September 2017 (29 boys and 32 girls, average age of 22.8 months) and a control group with 58 non-CZS children born in the same period (25 boys and 33 girls, average age of 23.8 months). The functional clinical analysis considered the labial and lingual frena, tongue anterior projection, oral escape, palate form, and first tooth eruption. For the craniofacial analysis, facial anthropometric points and the cephalic perimeter at the time were measured. Demographic data were collected from medical records, and a clinical exam was performed in order to register the intrabuccal characteristics and craniofacial measures. The chi-square test and Student's t-test were used with a significance level of 0.05. RESULTS: The narrow palate form, tongue anterior projection, oral escape, and late first tooth eruption were significantly more present in the group with microcephaly/CZS. As for the craniofacial analysis, face width (Bi-Zi), mandible width (Go-Go), height of face upper third (Tr-G), and monthly growth of cephalic perimeter were significantly smaller, whereas height of face lower third (Sn-Gn) was significantly bigger in the group with microcephaly/CZS (P < 0.05). CONCLUSION: Children with microcephaly resulting from a congenital Zika infection showed functional, oral, and maxillofacial changes and smaller facial development in comparison with non-CZS children in the same age group.

Gestational protein restriction alters the RANKL/OPG system in the dental germ of offsprings.

Evaluate the dentinogenesis in the offspring of rats submitted to gestational protein restriction (GPR). DESIGN: The offspring were evaluated at the 21st day of gestation (21 dG). Assessments were made of morphological parameters and the RANKL/OPG system - bone tissue maturation markers - in the upper incisor tooth germ. Pregnant 10-week-old female Wistar rats were divided into normal protein (NP, 17% casein, n = 5) and low protein (LP, 6% casein, n = 5) diet groups. At 21 dG, the offspring maxillae were collected for histomorphometric and immunohistochemical analyses. RESULTS: The LP group showed decreased thickness of the dentin and odontoblast cell layers on the tooth germ. GPR led to decreased OPG expression and increased RANKL expression in the incisor germ. CONCLUSION: The results suggested that gestational protein restriction altered odontoblast RANKL/OPG expression and decreased dentin matrix deposition and thickness in tooth development.

How is orthodontic treatment need associated with perceived esthetic impact of malocclusion in adolescents?

INTRODUCTION: The purpose of this research was to evaluate the esthetic impact of orthodontic treatment need in adolescents. METHODS: This cross-sectional study was performed with 1172 adolescents aged 12 (n = 638) years and 15 (n = 534) years from Salvador, Bahia, Brazil. The esthetic impact was the following outcome variables: Aesthetic Component of the Index of Orthodontic Treatment Need and the Oral Aesthetic Subjective Impact Scale. The normative orthodontic treatment need was assessed by the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC) and by the Dental Aesthetic Index (DAI). Logistic regression models were adjusted, estimating crude odds ratio with the respective 95% confidence intervals. The variables with P ≤0.20 in the individual analyses were tested in multiple logistic regression models, remaining the variables with P ≤0.05. RESULTS: The results showed a statistically significant association for the esthetic impact (Aesthetic Component of the Index of Orthodontic Treatment Need and the Oral Aesthetic Subjective Impact Scale) when assessing the normative orthodontic treatment need by the DAI (P <0.05). However, there was no significant association between subjective esthetic impact and normative needs when using the IOTN-DHC (P >0.05). CONCLUSIONS: DAI was more associated with the adolescents' esthetic concern than IOTN-DHC and should be the Index of Orthodontic Treatment Need to be selected to complement the patient's self-perception.

Effect of two corticotomy protocols on periodontal tissue and orthodontic movement.

Objective To compare two corticotomy surgical protocols in rats to verify whether they alter conventional orthodontic movement. Methodology Sixty Wistar rats were divided into three groups - orthodontic movement (CG), orthodontic movement and corticotomy (G1) and orthodontic movement with corticotomy and decortication (G2) - and euthanized after 7 and 14 days. Tooth movement (mm), bone volume fraction and bone volume ratio to total volume (BV/TV), and bone mineral density (BMD) were evaluated by micro-CT. The total amount of bone was measured in square millimeters and expressed as the percentage of bone area in the histomorphometry. The number of positive TRAP cells and RANK/RANKL/OPG interaction were also investigated. Results Day 14 showed a statistically significant difference in orthodontic tooth movement in CG compared with G1 (7.52 mm; p=0.009) and G2 (7.36 mm; p=0.016). A micro-CT analysis revealed a difference between CG, G1 and G2 regarding BV/TV, with G1 and G2 presenting a lower BV/TV ratio at 14 days (0.77 and 0.73 respectively); we found no statistically significant differences regarding BMD. There was a difference in the total amount of bone in the CG group between 7 and 14 days. At 14 days, CG presented a significantly higher bone percentage than G1 and G2. Regarding TRAP, G2 had more positive cells at 7 and 14 days compared with CG and G1. Conclusion Corticotomy accelerates orthodontic movement. Decortication does not improve corticotomy efficiency.

Photobiomodulation for the treatment of periodontal pockets in patients with type 2 diabetes: 1-year results of a randomized clinical trial.

This study investigated the local effect of photobiomodulation (PBM) for the treatment of periodontal pockets in patients with periodontitis and type 2 diabetes. Thirty-eight periodontal pockets presenting probing depth (PD) and clinical attachment level (CAL) ≥ 5 mm were selected from 19 patients (two pockets/patient). The selected periodontal pockets were randomly assigned to receive mechanical debridement only (control group) or mechanical debridement with PBM (PBM group). Clinical measures, such as PD, CAL, bleeding on probing (BoP), and presence of supragingival biofilm (PI), were collected and compared at baseline, 3, 6, and 12 months. After 12 months, no statistically difference was observed for mean PD and mean CAL when control and PBM groups were compared. The frequency of pockets with PD 5-6 mm was significantly lower for the PBM group at 6 months when compared to the control group. Pockets with PD ≥ 7 mm changed significantly between baseline and 3, 6, and 12 months for the PBM group, while for the control group, statistical significance was only observed between baseline and 6 months. The PBM protocol used in this study did not provide significant changes for PD and CAL in periodontal pockets when compared to mechanical therapy only. However, PBM was more effective in reducing the percentage of moderate periodontal pockets at 6 months in patients with type 2 DM.

Do electrical current and laser therapies improve bone remodeling during an orthodontic treatment with corticotomy?

OBJECTIVES: Evaluate the bone remodeling during orthodontic movement with corticotomy when submitted to low-intensity electrical stimulation application (microcurrent-MC) and low-level laser therapy (LLLT). MATERIAL AND METHODS: One hundred and fifty Wistar rats were divided into the following 5 groups: (C) submitted to tooth movement; (Cort) tooth movement/corticotomy; (Cort-L) tooth movement/corticotomy/laser AsGaAl 808 nm (4.96J/50s); (Cort-Mc) tooth movement/corticotomy/microcurrent (10 µA/5 min); (Cort-L-Mc) tooth movement/corticotomy and laser/microcurrent alternated. Inflammation, angiogenesis, and osteogenesis were evaluated in the periodontal ligament (PDL) and alveolar bone on the 7th, 14th, and 21st days of orthodontic movement. RESULTS: The quantification of inflammatory infiltrate, angiogenesis and expression of TGF-ß1, VEGF, and collagen type I were favorably modulated by the application of therapies such as low-level laser therapy (LLLT), MC, or both combined. However, electrical stimulation increased fibroblasts, osteoclasts and RANK numbers, birefringent collagen fiber organization, and BMP-7 and IL-6 expression. CONCLUSIONS: Low-level laser therapy (LLLT) and MC application both improved the process of bone remodeling during orthodontic treatment with corticotomy. Still, electrical current therapy promoted a more effective tooth displacement but presented expected root resorption similar to all experimental treatments. CLINICAL RELEVANCE: It is important to know the effects of minimally invasive therapies on cellular and molecular elements involved in the bone remodeling of orthodontic treatment associated with corticotomy surgery, in order to reduce the adverse effects in the use of this technique and to establish a safer clinical routine.

Macroscopic and radiographic aspects of orthodontic movement associated with corticotomy: animal study.

INTRODUCTION: To quantify the rate of tooth movement in two corticotomy protocols in an experimental model in rats through macroscopic and radiographic analysis. METHODS: The animals were divided into three groups: orthodontic movement (CO), orthodontic movement plus corticotomy surgery (G2), and orthodontic movement and corticotomy surgery with decorticalization (G3).The euthanasia occurred in 7 and 14 days. The data were statistically analyzed (p < 0.05). RESULTS: The CO presented lower distance between the mesial surface of the first molar and the distal surface of the third molar when compared to the G2 (6.96 ± 0.24, p = 0.009) and G3 (6.93 ± 0.18, p = 0.016) in the macroscopic analysis. In the 7 days, there was no statistically significant radiographic difference between the three groups: CO(0.94 ± 0.21 mm2), G2(1.05 ± 0,27 mm2), and G3(1.08 ± 0.27 mm2).There was a statistically significant difference between CO (0.87 ± 0.12 mm2), G2 (1.00 ± 0.12 mm2), and G3 (1.11 ± 0.14 mm2) at 14 days. There was a statistically significant linear difference between the groups in all periods. CONCLUSION: Tooth movement and the region of interest were influenced by corticotomy, regardless of the surgical technique in the 14 days.

Electrical stimulation: Complementary therapy to improve the performance of grafts in bone defects?

The limitations of bone reconstruction techniques have stimulated the tissue engineering for the repair of large bone defects using osteoconductive materials and osteoinductive agents. This study evaluated the effects of low intensity electric current on the inorganic bovine graft in calvaria defects. Bone defects were performed with piezoelectric system in the calvaria of Wistar rats divided into four groups (n = 24): (C) without grafting and without electrical stimulation; (E) with grafting; (MC) without grafting and submitted to electrical stimulation; (MC + E) with grafting and submitted to electrical stimulation. Inflammatory, angiogenic and osteogenic events during bone repair at the 10th, 30th, 60th, and 90th days were considered. Several inflammatory markers demonstrated the efficacy of grafting in reducing inflammation, particularly when subjected to electrical stimulation. Angiogenesis and collagen organization were more evident by electrical stimulation application on the grafts. Moreover, the osteogenic cell differentiation process indicated that the application of microcurrent on grafting modulated the homeostasis of bone remodeling. It is concluded that microcurrent favored the performance of grafts in calvarial rat model. Low-intensity electrical current might improve the osteoconductive property of grafting in bone defects. Therefore, electrical current becomes an option as complementary therapy in clinical trials involving bone surgeries and injuries. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 924-932, 2019.

Evaluation of the local effect of nonsurgical periodontal treatment with and without systemic antibiotic and photodynamic therapy in generalized aggressive periodontitis. A randomized clinical trial.

BACKGROUND: This study's aim was to evaluate the local effect of clarithromycin associated with antimicrobial photodynamic therapy (aPDT) in the treatment of generalized aggressive periodontitis. MATERIALS AND METHODS: The study sample comprised 72 periodontal pockets on single-rooted teeth in multiple quadrants, with both probing depth and clinical attachment level ≥5 mm, and with bleeding on probing. The pockets were randomly distributed into four groups (n = 18 each) that received ultrasonic periodontal debridement in addition to placebo (the UPD group), systemic clarithromycin (the UPD + CLM group), aPDT (the UPD + aPDT group), or both systemic clarithromycin and aPDT (the UPD + CLM + aPDT group). The measurements were performed prior to treatment (baseline) and at 3 and 6 months postoperatively. The following parameters were evaluated: plaque index, bleeding on probing, probing depth, gingival recession, and clinical attachment level. A 5% significance level was used in the statistical analysis. RESULTS: At 3 months, UPD + aPDT, UPD + CLM, and UPD + CLM + aPDT groups all exhibited reduced probing depths relative to the UPD group (p < 0.05). However, at 6 months, the reduction in mean probing depth was greater in the antibiotic groups (UPD+CLM and UPD+CLM+aPDT) than in the UPD and UPD+aPDT groups (p < 0.05). Regarding clinical attachment level, only the UPD+CLM+aPDT group presented a significant gain relative to the UPD and UPD + PDT groups (p < 0.05). CONCLUSIONS: Ultrasonic periodontal debridement has greater clinical advantages when associated with clarithromycin than with associated with aPDT. However, the joint application of aPDT and clarithromycin did not present additional benefits.

Periodontal response to orthodontic tooth movement in diabetes-induced rats with or without periodontal disease.

BACKGROUND: Systemic conditions can influence orthodontic tooth movement. This study evaluates histologic periodontal responses to orthodontic tooth movement in diabetes-induced rats with or without periodontal disease. METHODS: Forty Wistar rats were divided according their systemic condition (SC) into diabetic (D) and non-diabetic (ND) groups. Each group was subdivided into control (C), orthodontic tooth movement (OM), ligature-induced periodontitis (P) and ligature-induced periodontitis with orthodontic movement (P+OM) groups. Diabetes mellitus (DM) was induced with alloxan monohydrate, and after 30 days, the P group received a cotton ligature around their first lower molar crown. An orthodontic device was placed in OM and P+OM groups for 7 days, and the animals were then euthanized. RESULTS: Differences in OM between D and ND groups were not significant (6.87± 3.55 mm and 6.81 ± 3.28 mm, respectively), but intragroup analysis revealed statistically significant differences between the P+OM groups for both SCs. Bone loss was greater in the D group (0.16 ± 0.07 mm2 ) than in the ND group (0.10 ± 0.03 mm2 ). In intragroup analysis of the D condition, the P+OM group differed statistically from the other groups, while in the ND condition, the P+OM group was different from the C and OM groups. There was a statistically significant difference in bone density between D and ND conditions (18.03 ± 8.09% and 22.53 ± 7.72%) in the C, P, and P+OM groups. CONCLUSION: DM has deleterious effects on bone density and bone loss in the furcation region. These effects are maximized when associated with ligature-induced periodontitis with orthodontic movement.

Evolution of Periodontal Disease: Immune Response and RANK/RANKL/OPG System.

The aim of this study was to evaluate markers of bone loss and immune response present in evolution of periodontal disease. One hundred and two Wistar rats were divided into three animals groups: PD0, without ligation and PD15 days and PD60 days, submitted to ligation placement with a sterile 3-0 silk cord in the cervical region of the upper first molar on both sides. Samples were obtained from the gingival tissue for histomorphometric analysis, immunohistochemical analysis of RANK, RANKL, OPG, characterization of the inflammatory infiltrate, quantification of nitric oxide, MCP-1, RANTES, IP10 chemokines, and expression of the TGF-b1, VEG, and bFGF. The number of inflammatory cells in gingival tissue was higher in PD60 samples. The collagen content and the area occupied by birefringent collagen fibers were lower for PD60. Differential leukocyte counting showed that there was a significantly higher polymorphonuclear influx in group PD15, while PD60 showed a greater number of lymphocytes. PD60 showed higher RANTES, IP-10, MCP-1 gene transcripts, as well as a higher nitric oxide concentration. Clinical evaluation revealed that the PD60 group presented an increase in furcal area. In conclusion, in this animal model the increase of RANK/RANKL and HGF markers is related to a specific immune response, and probably contributed to the evolution of periodontal disease. Investigating the effect of these biomarkers can help in targeted therapy for bone resorption, since blocking these can inhibit bone loss.

Debonding forces of different pads in a lingual bracket system.

OBJECTIVE:: To evaluate the shear bond strength of lingual orthodontic brackets with resin or metal pads, the location of bond failure and the adhesive remnant index (ARI). METHODS:: A total of 40 extracted upper premolars were randomly divided into two groups of 20 each: bonding with brackets having (1) pads with extended resin directly on the lingual surface of teeth, and (2) pads with metal custom base on the lingual surface of teeth. The debonding force was measured with an Instron universal testing machine. A Student's t-test was used to assess the difference between groups (α = 0.05). RESULTS:: The results showed a significant difference between the groups (p < 0.001). The shear bond strength of metal pads was significantly higher than resin pads. CONCLUSIONS:: Within the limitations of this in vitro study, it was concluded that the bond strength of lingual brackets with metal pads was higher than that of brackets with composite resin pads, due to the metal part being a single unit and welded. The failure location in the region between the bracket and the resin pad affected a higher percentage of the resin pads than the metal pads.

Salud cardiovascular en habitantes de Atahualpa: características y correlatos / Cardiovascular health status in Atahualpa residents: characteristics and correlates

RESUMEN Las enfermedades vasculares son consideradas como las nuevas epidemias de salud en América Latina debido al aumento en la expectativa de vida y a cambios en el estilo de vida de sus habitantes. El conocimiento del estado de salud cardiovascular (SCV) de estas poblaciones es mandatorio para implementar estrategias costo-efectivas dirigidas a reducir la prevalencia de estas enfermedades en la región. En el Proyecto Atahualpa se ha valorado el estado de SCV de los participantes, utilizando los marcadores de salud propuestos por la Asociación Americana del Corazón. El estudio basal incluyó 616 sujetos libres de enfermedad cerebrovascular y cardiopatía isquémica, con edad ≥40 años. De estos, el 2.1% tuvieron un estado de salud ideal, el 28.1% intermedio y el 69.8% pobre. Los peores marcadores incluyeron presión arterial, glucosa en ayunas e índice de masa corporal. La posibilidad de tener un estado de SCV pobre estuvo aumentada en sujetos ≥60 años y en aquellos con escolaridad primaria. Luego, comparamos el estado de SCV de nuestra población con la de hispanos enrolados en el NOMAS, y encontramos que los residentes de Atahualpa tuvieron mejores marcadores de salud, con excepción de los niveles de glucosa en ayunas. La posibilidad de tener 5-7 marcadores en rango ideal fue más elevada en los residentes de Atahualpa, independientemente de la edad. También realizamos un estudio para valorar la SCV dependiendo del aislamiento social y encontramos que el vivir solo se asoció con un peor estado de SCV. Otros estudios mostraron relación entre ciertas patologías del sueño y un peor estado de SCV. Finalmente, hemos empezado el programa "conoce tus números", el cual sumado a charlas comunitarias, se encuentra dirigido a mejorar la SCV de los residentes de Atahualpa y reducir la incidencia de eventos vasculares en la región.

ABSTRACT Stroke and cardiovascular diseases will be the next epidemics in Latin America due to changes in lifestyle and increased life expectancy. Knowledge of cardiovascular health (CVH) status of the population is mandatory to implement cost-effective strategies directed to reduce the burden of vascular diseases in the region. In the Atahualpa Project, we assessed the CVH status of participants using the metrics proposed by the American Heart Association. The basal study included 616 subjects free of stroke and ischemic heart disease aged ≥40 years. Of these, 2.1% had ideal, 28.1% had intermediate and 69.8% had poor CVH status. Poorest metrics were blood pressure, fasting glucose, and BMI. The odds for having a poor CVH status were increased in persons aged ≥ 60 years and in those with only primary school education. Then, we compared our results with the Hispanic population of the Northern Manhattan Stroke Study (NOMAS), and found that Atahualpa residents had significantly better metrics than those enrolled in the NOMAS, with the exception of fasting glucose levels. Likewise, the odds for having 5 to 7 ideal metrics were also better in Atahualpa residents, irrespective of age. We also conducted a case-control study to assess the CVH status of Atahualpa residents according to their living arrangements, and found that social isolation was associated with a worse CVH status in this population. A couple of studies showed correlation between some sleep related disorders and poor CVH status. We have also started an ongoing program called "known your numbers", which, together with community talks, is directed to improve the CVH status and to reduce the burden of vascular diseases in the region.

Deflection and Flexural Strength Effects on the Roughness of Aesthetic-Coated Orthodontic Wires.

The aim was to evaluate the flexural strength and the effects of deflection on the surface roughness of esthetic orthodontic wires. The sample consisted of 70 archwire 0.014-inch: polytetrafluorethylene (PTFE)-coated Nickel-Titanium (Niti) archwires (Titanol Cosmetic-TC, Flexy Super Elastic Esthetic-FSE, esthetic Nickel Titanium Wire-ANT); epoxy resin-coated Niti archwires (Spectra-S, Niticosmetic-TEC); gold and rhodium coated Niti (Sentalloy-STC) and a control group (superelastic Niti (Nitinol-NS). The initial roughness was evaluated with a rugosimeter. After that, the wires were submitted to flexural test in an universal testing machine. Each wire was deflected up to 2 mm at a speed of 1 mm/min. After flexural test, the roughness of the wires was evaluted on the same surface as that used for the initial evaluation. The data of roughness and flexural strength were analyzed by one-way ANOVA and Tukey's test (a=0.05). Student t-test compared roughness before and after deflection (a =0.05). The roughness of S and ANT (epoxy resin and PTFE-coated wires, respectively), before and after deflection, was significantly higher than the other groups (p<0.05). Wire deflection significantly increased the roughness of the wires S and STC (p<0.05). The flexural strength of groups FSE and NS (PTFE and uncoated) was higher compared with that of the other groups (p<0.05). We concluded that the roughness and flexural strength of the orthodontic wires does not depend on the type of the esthetic coating, but it is influenced by the method of application of this coating. The deflection can increase the roughness of the esthetic orthodontic wires.

Electrical stimulation enhances tissue reorganization during orthodontic tooth movement in rats.

OBJECTIVE: This study evaluated the effects of a low-intensity electric current on tissue reorganization during experimental orthodontic tooth movement. MATERIALS AND METHODS: Thirty-two animals were divided into two groups evaluated on days 3 and 7: OTM-orthodontic tooth movement and OTM + MC-orthodontic tooth movement and microcurrent application (10 µA/5 min). The samples were processed for histological, morphometric, and Western blotting analysis. RESULTS: Analysis of the periodontal ligament (PL) showed a significantly smaller number of granulocytes in the OTM + MC group on day 7.The number of fibroblasts was significantly higher in the OTM + MC group on days 3 and 7. The area of birefringent collagen fibers was more organized in the OTM + MC group on days 3 and 7. The number of blood vessels was significantly higher in the OTM + MC group on day 7. Microcurrent application significantly increased the number of osteoclasts in the compression region of the PL. In the OTM + MC group on day 7 of tooth movement, the expression of TGF-ß1 and VEGF was significantly reduced whereas the expression of bFGF was increased in PL. CONCLUSIONS: Electrical stimulation enhances tissue responses, reducing the number of granulocytes and increasing the number of fibroblasts, blood vessels, and osteoclasts and modulates the expression of TGF-ß1, VEFG, and bFGF. CLINICAL RELEVANCE: This technique is used in many areas of medicine, but poorly explored in dentistry and orthodontics. This treatment is cheap and non-invasive and can be applied by own orthodontist, and it can improve the treatment with a faster and safe tooth movement, without pain.

Effect of Acid Etching, Silane and Thermal Cycling on the Bond Strength of Metallic Brackets to Ceramic.

The aim of this study was to evaluate the effect of silanes, thermal cycling and acid etching on the shear bond strength (SBS) of metallic brackets to feldspathic ceramic. Feldspathic ceramic cylinders (Groups 1, 2, 5 and 6) were etched for 60 s with 10% hydrofluoric acid and Groups 3, 4, 7 and 8, without acid etching. Two layers of silane Clearfil Ceramic Primer (CCP, Groups 1 to 4) and two layers of RelyX Ceramic Primer (RCP, groups 5 to 8) were applied and dried for 60 s. Brackets were bonded to the cylinders with Transbond XT and light-activated for 40 s with Bluephase G2. All specimens were stored in deionized water at 37 °C for 24 h, and the specimens of groups 1, 3, 5 and 7 were submitted to 7,000 thermal cycles (5 °C/55 °C). After storage, the SBS test was performed at a crosshead speed of 1 mm/min. Data were subjected to three-way ANOVA and Tukey's post hoc test (α=0.05). The adhesive remnant index (ARI) was evaluated at 8x magnification. The SBS of CCP was significantly greater than of RCP (p<0.05), with or without thermal cycling. Thermal cycling significantly reduced the SBS (p<0.05). The groups submitted to acid etching showed significantly higher SBS than those without acid etching (p<0.05). In conclusion, thermal cycling reduced SBS for all groups. The best ceramic surface treatment for bracket bonding was achieved by acid etching and CCP silane. The ARI results showed predominance of score 0 for all groups.

Connective tissue graft associated or not with low laser therapy to treat gingival recession: randomized clinical trial.

BACKGROUND: To evaluate the treatment of gingival recession with a connective tissue graft (CTG) alone or in combination with low-level laser therapy (CTG + L). METHODS: Forty patients presenting 40 Miller Class I and II gingival recessions were included. The defects were randomly assigned to receive either CTG (n = 20) or CTG + L (n = 20). A diode laser (660 nm) was applied to the test sites immediately after surgery and every other day for 7 days (eight applications). RESULTS: The mean percentage of root coverage was 91.9% for the test group and 89.48% for the control group after 6 months (p > 0.05). The test group presented more complete root coverage (n = 13, 65%) than the control group (n = 7, 35%) (p = 0.04). Dentine sensitivity decreased significantly after 6 months in both groups (p < 0.001). The two groups showed improvement in aesthetics at the end of treatment. CONCLUSIONS: Low-level laser therapy may increase the percentage of complete root coverage when associated with CTG.