Therapeutic dosage of isotretinoin in rats may influence orthodontic tooth movement.

Objective Isotretinoin, also known as 13-cis-retinoic acid, is an isomer of tretinoin, the oxidized form of Vitamin A. Orthodontic tooth movement (OTM) is the result of a cascade of inflammatory responses stimulated by a physical element that is the force generated by orthodontic appliances. Isotretinoin is mainly used among adolescents and young adults, and coincidentally it is this age group that also undergoes orthodontic treatment. Materials and Methods Fifty-five animals were used, and they were randomly divided into 11 groups, containing 5 animals in each group. Group 1: Control; Group 2: OTM for 7 days; Group 3: OTM for 14 days; Group 4: Treated with isotretinoin for 14 days with a dosage of 7.5 mg/kg/day; Group 5: Treated with isotretinoin for 14 days with a dosage of 1.0 mg/kg/day; Group 6: Treated with isotretinoin for 21 days with a dosage of 7.5 mg/kg/day; Group 7: Treated with isotretinoin for 21 days with a dosage of 1.0 mg/kg/day; Group 8: Treated with isotretinoin for 14 days with a dosage of 7.5 mg/kg/day and undergoing OTM for 7 days; Group 9: Treated with isotretinoin for 14 days with a dosage of 1.0 mg/kg/day and undergoing OTM for 7 days; Group 10: Treated with isotretinoin for 21 days with a dosage of 7.5 mg/kg/day and undergoing OTM for 14 days; Group 11: Treated with isotretinoin for 21 days with a dosage of 1.0 mg/kg/day and undergoing OTM for 14 days. In Groups 8, 9, 10 and 11, the animals were treated with isotretinoin for 7 days before OTM and maintained during the movement period in the respective groups. Results There was a significant difference in microtomographic parameters, including Trabecular Volume (BV/TV), Trabecular Thickness (Tb.Th), Number of Trabeculae (Tb.N), and Trabecular Separation (Tb.Sp), between the groups. The group that received orthodontic force in conjunction with isotretinoin treatment at a dosage of 7.5 mg/kg/day exhibited lower tooth displacement over a period of 21 days and 14 days. Conclusion Isotretinoin caused a reduction in tooth displacement during OTM when administered at a dose of 7.5 mg/kg/day and isotretinoin did change the microtomographic parameters of treated animals.

Corrosion-induced changes in surface properties and roughness of orthodontic wires.

INTRODUCTION: This study aimed to investigate the surface free energy and surface roughness (SR) of metallic alloys under the influence of acid solutions. METHODS: The experiment involved the use of 270 rectangular wire samples measuring 0.019 × 0.025-in. These samples were sourced from 3 different commercial brands: Dentsply GAC, American Orthodontics, and Orthoclassic. This in vitro study categorized the samples into 3 groups based on the solutions employed: deionized water, citric acid, and phosphoric acid. Each group consisted of 90 samples, with 30 samples representing each type of alloy-stainless steel, nickel-titanium, and titanium molybdenum alloy (TMA). The wire segments were immersed in their respective solutions for 72 hours at a controlled temperature of 37°C, with continuous orbital agitation at 130 rpm. After the immersion period, the study analyzed both surface free energy and SR. The mean values obtained were subjected to an analysis of variance at a significance level of 5%. RESULTS: All alloys displayed hydrophobic behavior, as indicated by interaction free energy values <0. In acidic environments (phosphoric acid and citric acid), significant differences were observed among different brands and alloys, affecting surface energy and interaction free energy. Variations in SR among metallic alloys included steel with the lowest SR variations, followed by nickel-titanium and TMA. Notably, the TMA alloy stood out with significantly higher surface energy compared with that of the other alloys (P <0.001). CONCLUSIONS: In this study, all examined alloys demonstrated a hydrophobic nature, suggesting a limited attraction to water. Notably, TMA exhibited the least hydrophobic behavior among the alloys studied. However, when exposed to citric acid, TMA displayed the most substantial alterations in its surface properties. These results underscored the significance of accounting for the distinctive properties of each alloy and their responses to diverse challenges, such as exposure to acidic solutions, during the selection of orthodontic wires for orthodontics treatment.

Effects of nano-sized sodium hexametaphosphate on the viability, metabolism, matrix composition, and structure of dual-species biofilms of Streptococcus mutans and Candida albicans.

This study evaluated the effects of micrometric or nano-sized sodium hexametaphosphate (HMPnano), combined or not with fluoride (NaF, 1100 ppm), on dual-species biofilms of Streptococcus mutans and Candida albicans. Biofilms were treated with solutions containing the polyphosphates at 0.5% or 1.0%, with/without fluoride (F), in addition to positive and negative controls. Biofilms were analysed by colony-forming units (CFU) counting, metabolic activity, production of biomass, composition of extracellular matrix, and structure. 1% HMPnano + F led to the lowest S. mutans CFU, while C. albicans CFU counts were not affected by any solution. 1% HMPnano led to the lowest metabolic activity, except for 1% HMPnano + F. All solutions promoted reductions in biofilm biomass compared to controls. Also, 1% HMPnano + F promoted the lowest concentrations of carbohydrates in the biofilm matrix, besides substantially affecting biofilms' structure. In conclusion, HMPnano and F promoted higher antibiofilm effects compared with its micrometric counterpart for most of the parameters assessed.

Effect of sodium hexametaphosphate and fluoride on dual-species biofilms of Candida albicans and Streptococcus mutans.

This study evaluated the effect of sodium hexametaphosphate (HMP), administered alone or in combination with fluoride (F), on dual-species biofilms of Streptococcus mutans and Candida albicans. Biofilms were treated with HMP solutions at 0.25%, 0.5% and 1%, alone or combined with F (0.05%), and compared by evaluating their structure and quantifying the colony-forming units (CFUs), metabolic activity, production of biomass and extracellular matrix components. All HMP-containing solutions were capable of reducing metabolic activity, the biofilm biomass, and the extracellular matrix components. Furthermore, the treatment with 1% HMP/F significantly reduced the CFUs of S. mutans, although it showed no effect on the CFUs of C. albicans, in the dual-species biofilms. In general, the combination of HMP and F influenced all the parameters analyzed from dual-species biofilms, except the CFUs of C. albicans.

Evaluation of the aesthetic effect, enamel microhardness and trans-amelodentinal cytotoxicity of a new bleaching agent for professional use containing trimetaphosphate and fluoride.

This study evaluated the effects of calcium gluconate (CaGlu), sodium fluoride (NaF), sodium trimetaphosphate (TMP), and NaF/TMP when added to a 35% hydrogen peroxide (H2O2) bleaching gel on the color change, enamel hardness, penetration and cytotoxicity trans-amelodentinal. Bovine enamel/dentin disks (n = 288) were divided according to the bleaching gel: 35% H2O2; 35% H2O2 + 0.05% NaF; 35% H2O2 + 0.25% TMP; 35% H2O2 + 0.05% NaF + 0.25% TMP; 35% H2O2 + 0.1% NaF + 1% TMP and 35% H2O2 + 2% CaGlu. The bleaching gels were applied thrice (40 min/session) at 7-day intervals between each application. Then, the color change, percentage of surface hardness loss (%SH), cross-sectional hardness (ΔKHN), trans-amelodentinal penetration of H2O2, cell viability and morphology (MDPC-23 odontoblast-like cells), alkaline phosphatase activity (ALP) and deposition of mineralization nodules were determined. The data were submitted to ANOVA, followed by the Student-Newman-Keuls test (p < 0.05). All bleaching gels showed significant color changes after treatment (p < 0.001). Mineral loss (%SH and ΔKHN) and H2O2 penetration were lower for 35% H2O2/0.1% NaF/1% TMP; 35% H2O2/2% CaGlu, meanwhile, showed higher values, compared to the other groups (p < 0.001). Cell viability was around 9%, except for the bleaching gel containing 35% H2O2/0.1% NaF/1% TMP with 12.8% (p < 0.05). ALP was higher for groups containing TMP compared to other whitening gels (p < 0.05). The formation of mineralization nodules was greater for gels containing NaF/TMP or CaGlu (p < 0.05). The alterations of cell morphology were intense for all bleaching gels. It was concluded that the addition of NaF/TMP in-office bleaching did not interfere in bleaching efficacy, reduced enamel demineralization, H2O2 penetration and cytotoxicity.

Incorporation of chlorhexidine and nano-sized sodium trimetaphosphate into a glass-ionomer cement: Effect on mechanical and microbiological properties and inhibition of enamel demineralization.

OBJECTIVE: To evaluate the antimicrobial/antibiofilm and mechanical properties, and the effect on enamel demineralization of a resin-modified GIC (RMGIC) containing CHX and nano-sized sodium trimetaphosphate (TMP). METHODS: RMGIC was associated with CHX (1.25 or 2.5%) and/or TMP (7 or 14%). Antimicrobial and antibiofilm activity were assessed using agar diffusion test and evaluation of biofilm metabolism, respectively. In addition, fluoride (F) and TMP releases as well as the diametral tensile (DTS) and compressive (CS) strength were determined. The percentage of mineral loss (%SH), integrated loss of subsurface hardness (ΔKHN) and enamel F concentrations were also evaluated. RESULTS: RMGICs containing CHX associated or not with TMP presented higher inhibition zones and effect on S. mutans biofilm. A reduction on CS was observed only for RMGIC + 2.5%CHX and on DTS for RMGIC + 2.5%CHX + 14%TMP. The highest F and TMP releases and lowest %SH and ΔKHN values were detected for RMGIC + 1.25%CHX + 14%TMP and RMGIC + 2.5%CHX + 14%TMP. Higher enamel F concentrations were observed for TMP groups. CONCLUSION: 1.25%CHX and 14%TMP increased antimicrobial/antibiofilm action and the ability to prevent enamel demineralization, with minimal effect on the mechanical properties of RMGIC. CLINICAL SIGNIFICANCE: RMGIC containing CHX and TMP is an alternative material for patients at high risk for dental caries and can be indicated for low-stress regions or provisional restorations.

In situ effect of fluoride toothpaste supplemented with nano-sized sodium trimetaphosphate on enamel demineralization prevention and biofilm composition.

OBJECTIVE: To evaluate the effect of a fluoride toothpaste containing nano-sized sodium trimetaphosphate (TMPnano) on enamel demineralization in situ and composition of the biofilm. DESIGN: This crossover double-blind study consisted of four phases (seven days each) and 12 volunteers who wore oral appliances containing four enamel bovine blocks. The cariogenic challenge was performed by 30% sucrose solution (6x/day). The toothpaste treatments (3x/day) were as follows: no F/TMP/TMPnano (Placebo), 1100 ppm F (1100F), 1100F plus 3% micrometric or nano-sized TMP (1100F/TMP; 1100F/TMPnano). Percentage of surface hardness loss (%SH), and integrated loss of subsurface hardness (ΔKHN), as well as enamel calcium (Ca), phosphorus (P), and fluoride (F) were determined. Moreover, biofilm formed on the blocks were analyzed for F, Ca, P, and insoluble extracellular polysaccharide (EPS) concentrations. Data were analyzed using one-way ANOVA, repeated measures followed by Fisher LSD test (p < 0.001). RESULTS: 1100F/TMPnano promoted the lowest %SH and ΔKHN among all groups (p < 0.001). Regarding the F concentrations in the enamel and in the biofilm, there were no significant differences between 1100 F and 1100 F/TMPnano, but significantly increased enamel Ca concentrations (p < 0.001). 1100F/TMPnano showed lower values of EPS concentration when compared with 1100F (∼80%) (p < 0.001). CONCLUSION: 1100F/TMPnano promoted a greater protective effect against enamel demineralization and significantly affected the composition of biofilm formed in situ when compared to 1100F toothpaste.

Mouthwash containing Croton doctoris essential oil: in vitro study using a validated model of caries induction.

AIM: To validate an in vitro caries model and to evaluate an experimental mouthwash containing Croton doctoris essential oil.  Materials & methods: To validate the experimental model, we used McBain medium and polymicrobial biofilms. The EOM (essential oil mouthwash) was tested using the validated model. Microbial composition (colony-forming unit/ml), acidogenicity, enamel demineralization (percentage of surface enamel hardness loss), cytotoxicity and essential oil composition were evaluated. RESULTS: The model was validated with 0.5% sucrose, duration of 4 days and treatments twice per day. There were statistically significant differences between the EOM, the negative control and chlorhexidine mouthwash in colony-forming unit/ml and percentage of surface enamel hardness loss. Cytotoxicity was similar to that of chlorhexidine mouthwash.  A total of 66.11% of the essential oil consists of sesquiterpenes. CONCLUSION: The experimental mouthwash showed antimicrobial activity against polymicrobial biofilms and reduced enamel demineralization.

pH changes of mixed biofilms of Streptococcus mutans and Candida albicans after exposure to sucrose solutions in vitro.

OBJECTIVE: This study aimed to standardize an in vitro experimental model able to reproduce the pH changes that occur in dental biofilm under in vivo conditions, using a mixed biofilm of Streptococcus mutans and Candida albicans. DESIGN: Biofilms were developed for 96 h, and exposed to three different concentrations of sucrose (10, 20 or 30%) during 1, 3 or 5 min. The pH was measured before exposure to sucrose, immediately after its removal from the biofilms, and at 1, 3, 5 and 10 min after removal. RESULTS: Sucrose solutions at 10 and 20% required 1 min to significantly reduce the biofilm pH, while for 30% sucrose a significant reduction was already seen immediately after its removal, even for the shortest exposure time. For an exposure of 3 min to 20% sucrose, the biofilm pH attained the critical value for hydroxyapatite dissolution when measured 1 min after sucrose removal, followed by a recovery phase. CONCLUSIONS: A mixed biofilm of S. mutans and C. albicans exposed to a 20% sucrose solution for 3 min exhibited a pattern of pH change similar to that observed in vivo, despite at a higher speed when compared to in vivo conditions.

Displasia ectodérmica en odontopediatría / Displasia ectodérmica em odontopediatria / Ectodermal dysplasia in pediatric dentistry

Ectodermal dyspasia (ED) is a hereditary disease that includes genetic and environmental changes. ED causes hypodontia, dystrophic nails, sparse hair and dental anomalies. Oral rehabilitation treatment for pediatric patients with ED is difficult because of continuous development and craniofacial growth. The aim of this study was to present a case report of oral rehabilitation in pediatric patients diagnosed with ED. A 5- year, 6-month-old girl reported to the clinic of Pediatric Dentistry in University Anhanguera UNIDERP-BR. Extraoral examination showed that the patient was an oral breather, and presented with decreased lower face height, protruding and everted lips, prominent forehead, "horse saddle" nose, lack of hair, eyelashes and eyebrows, thin and dry skin. Intraoral examination demonstrated absence of teeth: 51/52, 61/62/63, 71/72, 81/82 and tree conical teeth: 53, 73 and 83. The radiographic examination revealed agenesis of 9 primary teeth and of the buds of the following permanent teeth: 11/12/13, 21/22/23, 41/42, 31/32, we observed the presence of teeth buds of 33 and 43. Considering physical and radiographic characteristics hydrotic ectodermal was diagnosed. As clinical management, we opted for the installation of removable functional aesthetic maintainers, favoring the speech normality, swallowing, lip and lingual muscle tone and social development.

A displasia ectodérmica (DE) caracteriza-se por uma doença hereditária que consiste em alterações genéticas e ambientais, provocando hipodontia, unhas distróficas, cabelos escassos e anomalias dentárias. O tratamento reabilitador em pacientes pediátricos com DE se torna difícil devido ao contínuo desenvolvimento e crescimento crânio-facial dessas crianças. O presente trabalho tem como objetivo relatar um caso clínico de reabilitação oral em paciente pediátrico diagnosticado com DE. Paciente sexo feminino, com 5 anos e 6 meses de idade compareceu a clínica de Odontopediatria na UNIDERP. Ao exame físico, extra-oral, constatou-se que a paciente era respiradora bucal, e tinha como características a diminuição do terço inferior da face, lábios protusos e evertidos, fronte proeminente, nariz em "sela", escassez de pelos, cílios e sobrancelha, pele fina e seca. No exame intra-oral observou-se ausência dos elementos dentários, 51/52, 61/62/63, 71/72, 81/82, e os elementos 53, 73 e 83 apresentando aspecto conóide. Ao exame radiográfico constatou-se a agenesia de 9 dentes decíduos e dos germes dos seguintes dentes permanentes: 11/12/13, 21/22/23, 41/42, 31/32 e ainda observou-se a presença dos germes dos dentes 33 e 43. Baseado nas características físicas e radiográficas diagnosticou-se displasia ectodermica hidrótica. Como conduta clínica, optou-se pela instalação de mantenedores estéticos funcionais removíveis, favorecendo a normalidade da fala, deglutição, tonicidade muscular labial e lingual e do desenvolvimento social.

La displasia ectodérmica (DE) se caracteriza por ser una enfermedad hereditaria que consiste en alteraciones genéticas y ambientales, provocando hipodoncia, distrofia en uñas, cabello escaso y anomalías dentarias. El tratamiento de rehabilitación en pacientes pediátricos con DE es difícil debido al continuo crecimiento y desarrollo cráneo facial de estos niños. El presente trabajo tiene como objetivo relatar un caso clínico de rehabilitación oral en paciente pediátrico diagnosticado con DE. Paciente de sexo femenino, con 5 años y 6 meses de edad que compareció a la clínica de odontopediatría en la UNIDERP. Al examen físico, extra oral, se constató que la paciente era respiradora bucal, y presentaba disminución del tercio inferior de la cara, labios protruidos y evertidos, frente prominente, nariz en "silla de montar", escasez de cabello, pestañas y cejas, piel fina y seca. En el examen intraoral se observó ausencia de los siguientes dientes: 51/52, 61/62/63, 71/72, 81/82, y aspecto conoide de los dientes 53, 73 y 83. Al examen radiográfico se constató agenesia de 9 dientes primarios y de los gérmenes de los siguientes dientes permanentes: 11/12/13, 21/22/23, 41/42, 31/32, se observó la presencia de los gérmenes de los dientes 33 y 43. Con base en las características físicas y radiográficas se diagnosticó displasia ectodérmica hidrótica. Como conducta clínica, se optó por la instalación de mantenedores estéticos funcionales removibles, con el fin de favorecer la fonación, deglución, tonicidad muscular labial y lingual y el desenvolvimiento social.

Screening of plants with antimicrobial activity against enterobacteria, Pseudomonas spp. and Staphylococcus spp.

AIM: This study screened plants for antibacterial properties against bacteria of medical importance. MATERIALS & METHODS: 60 extracts were obtained from the leaves of ten plants (Jatropha weddelliana, Attalea phalerata, Buchenavia tomentosa, Croton doctoris, Mouriri elliptica, Mascagnia benthamiana, Senna aculeata, Unonopis guatterioides, Allagoptera leucocalyx and Bactris glaucescens) using different extraction methods: A) Ethanol 70°C/72 h; B) Water/5 min/100°C; C) Water/1 h/55°C; D) Water/72 h; E) Hexane/72 h and F) Ethanol 99°C/72 h. Enterobacteria/Pseudomonas and staphylococci reference strains and 201 clinical isolates were used. Primary screening was done using agar well-diffusion assay. MIC/minimum bactericidal concentration and chemical characterization were determined. RESULTS: Extracts 5F and 3A showed the best MIC/minimum bactericidal concentration against clinical isolates and showed the presence of phenols. CONCLUSION: The present study demonstrated that Mouriri elliptica and Buchenavia tomentosa were the most active plants against the studied bacteria.

Protective efficacy of Psidium cattleianum and Myracrodruon urundeuva aqueous extracts against caries development in rats.

This study evaluated the influence of Psidium cattleianum Sabine (Myrtaceae) and Myracrodruon urundeuva Allemão (Anacardiaceae) aqueous extracts on S. mutans counts and dental enamel micro-hardness of rats submitted to a cariogenic challenge. Sixty Wistar rats were distributed in three groups and received water (control) or aqueous extracts of Psidium cattleianum or Myracrodruon urundeuva as hydration solution. Initially the animals had their sublingual and submandibular salivary glands surgically removed and the parotid ducts ligated. Then the rats were inoculated with 10(6) CFU of Streptococcus mutans ATCC 35668 and were fed with a cariogenic diet. To detect and quantify the presence of S. mutans, oral biofilms were sampled and microbial DNA was extracted and submitted to amplification by means of real-time PCR (Polymerase Chain Reaction). After seven weeks the animals were sacrificed and enamel demineralization was analyzed by cross-sectional micro-hardness. Both extracts produced a significant reduction on S. mutans counts and decreased the enamel demineralization. It can be concluded that the extracts tested had a significant effect on S. mutans in oral biofilm of the rats, decreasing S. mutans accumulation and enamel demineralization.