Influence of chlorhexidine digluconate on biocompatibility of cements: Morphological and immunohistochemistry analysis.

In this study, the in vivo biocompatibility was evaluated by using conventional ionomer cements modified with Chlorhexidine (CHX) in different time intervals. In total, 105 male Wistar rats were randomized into seven groups: control, groups M, M10, M18 and groups RL, RL10, RL18 (M-Meron and RL-RivaLuting, and added CHX-10% and CHX-18%, respectively). Histological analyses of inflammatory infiltrate and collagen fibers, and immunohistochemistry of CD68+ for macrophages (MOs) and multinucleated giant cells (MGCs) were performed. Data were analyzed using the Kruskal-Wallis and Dunn (p < .05) tests. Intense inflammatory infiltrate was demonstrated in Group Riva CHX-18% within 7 and 15 days (p < .05), without differences after 30 days. For collagenization, healing of the groups was compatible with that of control in 15 and 30 days (p > .05). Immunomarking of CD68+ was more significant in the groups with higher concentration of CHX. There was significant difference in quantity of MGCs in groups with 18% CHX, Meron (p = .001) in 7 days, and in Riva at 30 days (p = .001). Significant difference was also found in quantities of MOs in Groups Meron and Riva in 7 days (p = .001), and only in Riva at 15 and 30 days (p = .001). The cements with addition of CHX demonstrated biocompatibility with tissues. Riva CHX-18% had the most effect on cells of the inflammatory process but showed satisfactory tissue repair. RESEARCH HIGHLIGHTS: The concentration of 18% chlorhexidine was shown to be biocompatible with tissues; the slow release of chlorhexidine by the cements could significantly prolong its antibacterial effect on the oral medium.

Effect of Yellow Propolis on Biocompatibility of Cements: Morphological and Immunohistochemistry Analysis.

OBJECTIVE: The focus of this study was to evaluate the biocompatibility of ionomer cements modified with ethanolic extracts of propolis (EEP) in different concentrations and time intervals. MATERIALS AND METHODS: In total, one hundred and thirty-five male Wistar rats were randomized into nine groups: Control, Groups Meron, and Groups Ketac (conventional, and added with 10, 25, 50% EEP, respectively). Histological analyses of inflammatory infiltrate and collagen fibers, and immunohistochemistry of CD68+ for macrophages (MOs) and multinucleated giant cells (MGCs) were performed. STATISTICAL ANALYSIS: Data were analyzed using the Kruskal-Wallis and Dunn (p < 0.05) tests. RESULTS: Intense inflammatory infiltrate was demonstrated in the cements with 10% EEP at 7 days and 15 days (p < 0.05), only Group Ketac 10% EEP (p = 0.01) at 30 days. A smaller quantity of collagen fibers was observed in the cements with 10% EEP (p = 0.01) at 7 days, and Group Meron 10% EEP (p = 0.04) at 15 days. MOs and MGCs showed significant difference for the cements with 10% EEP (p = 0.01) at 7 and 15 days. At 30 days, MOs persisted in the Groups with 10% EEP. CONCLUSIONS: The concentration of 10% EEP had the greatest influence on the inflammatory and tissue repair processes. The concentrations of 25 and 50% EEP demonstrated biocompatibility similar to that of cements that did not receive EEP.

Characteristics of patients seeking orthodontic retreatment.

BACKGROUND: The aim of this cross-sectional study was to investigate patients' experiences with previous orthodontic treatment for those seeking retreatment, and their expectations and motivation for doing so. METHODS: A total of 72 patients were invited to answer an anonymous questionnaire. Of these, 36 (13 men and 23 women, mean age 26.3 ± 5.8 years) were seeking retreatment (study group), and 36 (13 men and 23 women, mean age 25.5 ± 6.8 years) were seeking treatment for the first time (control group). Casts from both groups were assessed with the index of complexity, outcome, and need (ICON) score, to objectively determine the treatment need and complexity. Student`s t test for independent samples, and paired Student`s t test, were performed for comparisons between the retreatment and control groups, and between retreatment and previous treatment, respectively. RESULTS: There was no statistically significant difference between retreatment patients` motivation for the previous treatment and motivation for the retreatment. However, the mean visual analog scale (VAS) scores for motivation differed significantly between the retreatment and control groups (73.8 ± 23.9 and 87.5 ± 14.5, respectively). The mean ICON score of the retreatment group was lower than that for the control group (25 ± 14 and 31 ± 16, respectively). CONCLUSIONS: Patients seeking retreatment were less motivated for treatment, and tooth irregularity was the chief reason for seeking treatment in both groups. Although an objective treatment need was not observed in the 2 groups, all of them had some occlusal traits that clinically justified the orthodontic treatment.

Evaluation of resin composite staining by beverages with acid pH / Avaliação do manchamento de resinas compostas por bebidas de pH ácido

ABSTRACT Introduction: Composite resins are an extensively used esthetic material that has excellent adaptation, reproduces the characteristics of the tooth structure and is suitable for the conditions of the oral environment. However, this material is also very susceptible to staining due to pigmentation coming from the diet and habits of the patient. Objectives: To evaluate the staining of two brands of composite resin, one nanoparticle and a nanohybrid type (Filtek Z350XT® and IPS Empress Direct®), in direct contact with the acid pH of beverages. Methods: In total 40 specimens were made, 20 of each type of resin studied. After being inserted into a Teflon matrix and light activated, the samples were removed, stored in containers with 2 ml of artificial saliva and kept in the refrigerator. Every day 20 of these samples were placed in direct contact with 2 ml Gatorade, and the other 20 samples, in 2 ml of wine, each set for 30 minutes. After 30 minutes, the acid pH substances were removed, and 2 ml of artificial saliva was again placed in the container. This process was repeated every day for 10 days. Results: The results showed that the nanoparticle resin (Filtek Z350XT) was more susceptible to staining than the nanohybrid type (Empress Direct®) when in contact with the wine. When wine and Gatorade were compared, the solution with higher staining capacity was shown to be wine. Conclusion: The two resins tested were susceptible to staining in a 10-day period. Mottling and more staining was visibly detected after samples were immersed in the solution with the higher pH, and nanoparticulate resin was more susceptible to staining.

RESUMO Introdução: As resinas compostas são altamente utilizadas por serem um material estético, com excelente adaptação, reproduz as características da estrutura dental e se adequa ao meio bucal. Porém, este material é muito susceptível à pigmentação por corantes vindos da dieta e de hábitos do paciente. Objetivos: Avaliar o manchamento de duas marcas comerciais de resina composta: Nanoparticulada e Nanohíbrida, em contato direto com bebidas de pH ácido (Filtek Z350XT® e IPS Empress Direct®). Métodos: Foram confeccionados 40 corpos de prova, 20 de cada tipo de resina estudada, depois de inseridas em matriz de teflon e fotoativados, os corpos de prova foram removidos, armazenados em recipientes com 2ml de saliva artificial e mantidos na geladeira. Diariamente 20 dos mesmos eram colocados em contato direto com 20mL Gatorade e os outros 20mL de vinho durante 30 minutos cada. Passados os 30 minutos, as substâncias de pH ácido eram retiradas e novamente, 2 mL de saliva artificial eram colocadas no recipiente. Este processo foi repetido todos os dias durante 10 dias. Resultado: Os resultados mostraram que a resina nanoparticulada (Filtek Z350XT®) é mais susceptível ao manchamento que a nanohíbrida (Empress Direct®) quando em contato com o vinho. Quando comparados vinho e Gatorade, a solução com maior teor de manchamento é o vinho. Conclusão: As duas resinas testadas foram sensíveis ao manchamento num período de 10 dias, esse manchamento foi visivelmente detectado, a solução com o pH mais elevado manchou mais e a resina nanoparticulada é mais susceptível ao manchamento.

Effectiveness of Secondary Alveolar Bone Graft on Canine Eruption: Systematic Review.

There are controversies related to the effects of bone grafts on tooth eruption and impaction in patients with cleft lip and palate. The aim of this systematic review was to evaluate the effectiveness of bone grafting on eruption of canines in patients with unilateral cleft lip and palate (UCLP). An electronic search was conducted in six electronic databases and gray literature, without limitations on year of publication or language. The primary outcome was the increase in rate of canine eruption; the secondary outcomes were success of the bone graft, canine impaction due to agenesis of the lateral incisor, and effect of orthodontic treatment before and after bone grafting. The risk of bias was analyzed by means of the tool Cochrane risk of bias in nonrandomized controlled trials (NRCTs) of interventions (ROBINS-I). The certainty of the evidence was assessed for outcomes reported through a narrative synthesis using grading of recommendations, assessment, development and evaluation (GRADE) approach. Four NRCTs were included, with a total of 360 patients, 283 UCLP and 77 bilateral cleft lip and palate (BCLP). The studies reported association between the increase in the rate of tooth eruption and bone graft with very low certainty of evidence, and greater experience of surgical success, with low certainty of evidence. The majority of the studies found an association between increase in the rate of canine impaction and agenesis of the lateral incisor, with very low certainty of evidence. There was very low certainty of the efficacy of secondary alveolar bone grafting for increasing the rates of eruption and reducing impaction of the maxillary canine.

Delivering Beneficial Microorganisms for Corals: Rotifers as Carriers of Probiotic Bacteria.

The use of Beneficial Microorganisms for Corals (BMCs) to increase the resistance of corals to environmental stress has proven to be effective in laboratory trials. Because direct inoculation of BMCs in larger tanks or in the field can be challenging, a delivery mechanism is needed for efficient transmission of the BMC consortium. Packaged delivery mechanisms have been successfully used to transmit probiotics to other organisms, including humans, lobsters, and fish. Here, we tested a method for utilizing rotifers of the species Brachionus plicatilis for delivery of BMCs to corals of the species Pocillopora damicornis. Epifluorescence microscopy combined with a live/dead cell staining assay was used to evaluate the viability of the BMCs and monitor their in vivo uptake by the rotifers. The rotifers efficiently ingested BMCs, which accumulated in the digestive system and on the body surface after 10 min of interaction. Scanning electron microscopy confirmed the adherence of BMCs to the rotifer surfaces. BMC-enriched rotifers were actively ingested by P. damicornis corals, indicating that this is a promising technique for administering coral probiotics in situ. Studies to track the delivery of probiotics through carriers such as B. plicatilis, and the provision or establishment of beneficial traits in corals are the next proof-of-concept research priorities.