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1.
BMC Oral Health ; 21(1): 27, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33435927

RESUMO

BACKGROUND: Lisu is an ethnic minority group and most of them are living in Yunnan, China. This study investigated the oral health status among 12-year-old Lisu children in Yunnan. METHOD: This survey employed a multistage sampling method to recruit 12-year-old Lisu children. Two calibrated dentists performed the oral examinations in the primary schools. They examined dental caries, gingival bleeding and dental fluorosis using the diagnosis criteria recommended by the World Health Organization. A self-administrated questionnaire was distributed to the children to collect their sociodemographic background information and oral health-related behaviours. A chi-square test, the Mann-Whitney U test, zero-inflated negative binomial (ZINB) regression and multivariate logistic regression were used for statistical analysis. RESULTS: This survey invited 512 children, and 482 children (48% boys) participated in the study (response rate: 94%). Their caries prevalence was 35% and their caries experience in mean (SD) DMFT scores was 0.63 (0.10). The mean (SD) DT score was 0.60 (1.10), consisting 95% of the mean DMFT scores. No dental fluorosis was observed; whereas 426 children (88%) had gingival bleeding. Results of ZINB model indicated sex and sugary-snacking habits were related to the dental caries experience (p < 0.05). The gingival-bleeding prevalence was associated with the mother's education level, the child's monthly-pocket money and daily toothbrushing frequency (p < 0.05). CONCLUSION: Dental caries and gingival bleeding were prevalent among 12-year-old Lisu children in the Yunnan province in China, and most of the decayed teeth were unrestored. Dental fluorosis was not observed in the children.

2.
Arch Oral Biol ; 122: 105022, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418434

RESUMO

The objective of this study was to perform a comprehensive review of the use of antimicrobial peptides for the prevention and treatment of dental caries. The study included publications in the English language that addressed the use of antimicrobial peptides in the prevention and treatment of caries. These publications were also searchable on PubMed, Web of Science, Embase, Scopus, the Collection of Anti-Microbial Peptides and the Antimicrobial Peptide Database. A total of 3,436 publications were identified, and 67 publications were included. Eight publications reported seven natural human antimicrobial peptides as bactericidal to Streptococcus mutans. Fifty-nine publications reported 43 synthetic antimicrobial peptides developed to mimic natural antimicrobial peptides, fusing peptides with functional sequences and implementing new designs. The 43 synthetic antimicrobial peptides were effective against Streptococcus mutans, and nine peptides specifically targeted Streptococcus mutans. Ten antimicrobial peptides had an affinity for hydroxyapatite to prevent bacterial adhesion. Six antimicrobial peptides were also antifungal. Four antimicrobial peptides promoted remineralisation or prevented the demineralisation of teeth by binding calcium to hydroxyapatite. In conclusion, this study identified 67 works in the literature that reported seven natural and 43 synthetic antimicrobial peptides for the prevention and treatment of caries. Most of the antimicrobial peptides were bactericidal, and some prevented bacterial adhesion. A few antimicrobial peptides displayed remineralising properties with hydroxyapatite.


Assuntos
Antibacterianos/uso terapêutico , Cárie Dentária , Proteínas Citotóxicas Formadoras de Poros/uso terapêutico , Aderência Bacteriana/efeitos dos fármacos , Biofilmes , Cárie Dentária/tratamento farmacológico , Cárie Dentária/prevenção & controle , Durapatita , Humanos , Streptococcus mutans/efeitos dos fármacos , Remineralização Dentária
3.
J Dent ; 105: 103581, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33434634

RESUMO

OBJECTIVES: This study investigated the effects of a new strontium-doped bioactive glass and fluoride on hydroxyapatite crystallization. METHODS: We designed an in vitro experiment with calcium phosphate (CaCl2·2H2O + K2HPO4 in buffer solution) with different concentrations of strontium-doped bioactive glass (1 mg/mL or 5 mg/mL), and different concentrations of fluoride (0 ppm, 1 ppm or 5 ppm). Tris-buffered saline served as negative control. After incubation at 37 ℃ for 48 h, the shape and organization of crystals were examined by transmission electron microscopy (TEM) and electron diffraction. Structure of the crystals was assessed by powder X-ray diffraction (P-XRD) and unit cell parameters were calculated. Characterization of the crystals were performed by Raman spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR). RESULTS: TEM and selected-area electron diffraction revealed that the precipitates in all experimental groups were crystalline apatite. There was an interaction between strontium and fluoride with different concentrations on crystal thickness (p = 0.008). P-XRD indicated the formation of strontium-substituted-fluorohydroxyapatite and strontium-substituted-hydroxyapatite in the groups with both bioactive glass and fluoride. Expansion or contraction of crystal unit cell was influenced by the concentrations of strontium and fluoride. Raman spectra showed strong phosphate band at 960 cm-1 in all experimental groups and displayed no obvious shift. FTIR results confirmed the formation of apatite. CONCLUSIONS: The results of this study suggest that strontium-doped bioactive glass and fluoride have synergistic effects on hydroxyapatite crystallization. CLINICAL SIGNIFICANCE: Strontium-doped bioactive glass and fluoride have synergistic effects on hydroxyapatite crystallization by producing strontium-substituted-hydroxyapatite and strontium-substituted-fluorohydroxyapatite with enhanced bioactivity and reduced solubility which could be beneficial for caries management.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33499023

RESUMO

Qualitative research collects non-numerical data that explores human behaviour, attitudes, beliefs and personality characteristics unamendable to quantitative research. The qualitative research questions are open-ended, evolving and non-directional. The study design is flexible and iterative. Purposive sampling is commonly used. The sample size is determined by theoretical saturation. Data collection is generally through in-depth interviews, focus groups and observations. Qualitative research commonly uses thematic analysis and framework analysis, although there is no consensus on analysing qualitative data. The reporting format can be comprehensive, a summary, developmental or selective, subject to the research question. Qualitative research's potential functions are to describe the form or nature of what exists (contextual), to examine the reasons for or associations between what exists (explanatory), to appraise the effectiveness of what exists (evaluative), and to aid the development of strategies (generative). Qualitative research can be time consuming to conduct because it explores evolving questions; difficult to generalise because it recruits limited participants; and arduous when it comes to making systematic comparisons because responses are subjective. However, qualitative research can provide depth and detail, create openness, simulate people's individual experiences and avoid pre-judgements. This concise review provides an overview and suggestions for dental researchers when conducting a qualitative study.

5.
J Biomed Mater Res A ; 109(2): 207-218, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32441418

RESUMO

Cyclic adenosine monophosphate (cAMP) is a second messenger involved in the dental regeneration. However, efficient long-lasting delivery of cAMP that is sufficient to mimic the in vivo microenvironment remains a major challenge. Here, cAMP was loaded in stem cells from apical papilla (SCAPs) using layer-by-layer self-assembly with gelatin and alginate polyelectrolytes (LBL-cAMP-SCAPs). LBL-cAMP-SCAPs expressed cAMP and increased the phosphorylation level of cAMP-response element-binding protein (CREB) which were evaluated by immunofluorescence and western blotting (WB). Enzyme-linked immunosorbent assay (ELISA) demonstrated that a sustained release of cAMP and vascular endothelial growth factor (VEGF) were present up to 14 days. Scanning electron microscopy (SEM) found LBL-coated SCAPs exhibited a spheroid-like morphology. CCK8 and live/dead staining showed that LBL treatment had no significant effect on cell proliferation and viability. LBL-cAMP-SCAPs enhanced mineralized nodule formation and up-regulated the mRNA levels of the osteogenesis-related genes, as well as related transcription factor-2 protein level which were revealed by Alizarin red staining, RT-PCR and WB, respectively. In conclusion, LBL self-assembly loaded with cAMP promoted the osteo/odontogenic differentiation of SCAPs, thereby providing a potential strategy for bioactive molecular delivery in dental regeneration.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33373541

RESUMO

Objectives: This study was intended to investigate the caries prevention potential of carbon dioxide (CO2) laser (λ = 10,600 nm) irradiation followed by application of silver diamine fluoride (SDF) to enamel. Materials and methods: Human enamel specimens were randomly allocated to four groups (n = 10 per group). Group 1 specimens were treated with SDF; Group 2 specimens were treated with a CO2 laser; Group 3 specimens were irradiated with a CO2 laser then treated with SDF, and Group 4 specimens received no treatment. All specimens were subjected to pH cycling for cariogenic challenge. Lesion depth, microhardness, surface morphology, and elemental analysis were assessed. Results: The lesion depths for Groups 1-4 were 33 ± 16, 80 ± 9, 18 ± 15, and 102 ± 9 µm, respectively (p < 0.001; Group 3 < Group 1 < Group 2 < Group 4). Knoop hardness values for Groups 1-4 were 61 ± 19, 68 ± 20, 78 ± 27, and 36 ± 8, respectively (p = 0.002; Group 4 < Groups 1, 2, and 3). The enamel in Group 4 but not in the other groups showed a roughened surface resembling an acid-etched pattern. Calcium-to-phosphorus molar ratios of Groups 1-4 were 1.68 ± 60.09, 1.61 ± 0.06, 1.69 ± 0.10, and 1.49 ± 0.10, respectively (p < 0.001; Group 4 < Groups 1, 2, and 3). Conclusions: Using the CO2 laser or SDF separately enhanced the resistance of enamel to cariogenic challenge. Moreover, there was an additional effect of the combined use of the CO2 laser and SDF for preventing enamel demineralization.

7.
J Dent ; 104: 103526, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33188846

RESUMO

OBJECTIVES: Aim of this systematic review was to summarize the factors that affect the success rate of atraumatic restorative treatment (ART) restorations in children. DATA/SOURCES: Two independent reviewers conducted a literature search in the databases PubMed, Medline and Web of Science until October 2019 with no initial time limit. Articles reporting on clinical outcomes of ART restorations placed in children were included. STUDY SELECTION: A total of 67 articles were included in this review reporting on clinical outcomes of ART restorations placed in children in 47 studies. The overall estimated success rate and 95 % confidence interval (CI) of ART restorations were 0.71 (0.65-0.77) and 0.67 (0.56-0.78) at the 12-month and the 24-month follow-up, respectively. Operator was one of the significant factors associated with the success rate of ART restorations. ART restorations placed by dental students/therapists had a significantly lower success rate compared with those placed by dentists. Besides, type of restoration (single-surface vs. multiple-surface restoration) was also associated with the success rate of ART restorations. Other factors including dentition, restorative material, clinical setting, and moisture control method had no significant influence on the success rate of ART restorations in children. CONCLUSION: It is concluded that ART approach can be used to manage cavitated caries lesions in children. Operator and type of restoration are significant factors influencing the success rate of ART restorations. CLINICAL SIGNIFICANCE: This study provides valuable information on the factors that affect success rate of ART restorations in children, which helps clinicians to make informed decisions on provision of ART restorations in children.

8.
J Dent ; 103: 103512, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33157159

RESUMO

OBJECTIVES: To investigate the remineralising and staining effects of sodium fluoride (NaF) with silver nanoparticles (AgNPs) on artificial dentine caries. METHODS: Human dentine blocks with artificial caries were divided into four groups. Group 1 received 5 % NaF (22,600 ppm fluoride) with 4000 ppm AgNPs; group 2 received 4000 ppm AgNPs; group 3 received 5 % NaF, group 4 received deionised water (negative control). All groups underwent three biochemical cycles. Each cycle included Streptococcus mutans biofilm challenge and remineralisation process. The lesion depth, mineral-organic content, surface morphology and crystal characteristics of dentine blocks were evaluated using micro-computed tomography, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction. Colour change of dentine blocks was assessed using spectrophotometry. RESULTS: The mean lesion depths of groups 1-4 were 151.13 ± 29.13 µm, 172.38 ± 23.44 µm, 190.41 ± 32.81 µm and 221.24 ± 27.91 µm, respectively. The hydrogen phosphate-to-amide I ratios of groups 1-4 were 5.98 ± 0.36, 3.86 ± 0.56, 4.00 ± 0.67 and 2.53 ± 0.40, respectively. There was no significant interaction effect between AgNPs and NaF. SEM showed less exposure of dentine collagen fibres in group 1 when compared to other groups. X-ray diffraction revealed presence of silver chloride and metallic silver in group 1 and 2. There was no significant difference in colour change among the four groups (p = 0.74). CONCLUSIONS: NaF solution with AgNPs can remineralise dentine caries without staining. CLINICAL SIGNIFICANCE: Sodium fluoride solutions that include silver nanoparticles have potential uses in the management of caries.

9.
J Dent ; 103: 103522, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33166594

RESUMO

OBJECTIVE: The aim of this randomised non-inferiority clinical trial was to compare the effectiveness of semi-annual (every six months) applications of 25 % silver nitrate (AgNO3) solution followed by 5 % sodium fluoride (NaF) varnish to semi-annual applications of 38 % silver diamine fluoride (SDF) solution in arresting early childhood caries (ECC). METHODS: Three-year-old children with active cavitated carious lesions were recruited and randomly assigned to two intervention groups. Children in Group A received semi-annual applications of 25 % AgNO3 solution followed by 5 % NaF varnish on carious lesions. Children in Group B received semi-annual applications of 38 % SDF solution followed by a placebo varnish. One trained dentist assessed ECC status at baseline and in all follow-up examinations. An independent operator performed the interventions. The dentist, the children, and their caretakers were blinded to the intervention allocation. Data were analysed using a non-inferiority test. Group A's non-inferiority would be accepted if the lower limit of the 95 % confidence interval (CI) for the difference in the mean number of arrested decayed surfaces (ds) was greater than -0.5. RESULTS: At baseline, 1,070 children were recruited, and 535 children were assigned to each group. After 30 months, the mean arrested ds in Groups A (n = 447) and B (n = 433) were 3.7 ± 3.6 and 3.6 ± 3.7, respectively (p = 0.694). The difference in the mean arrested ds between the two groups was 0.088 (95 % CI: -0.351 to 0.526). CONCLUSION: Semi-annual application of 25 % AgNO3 followed by 5 % NaF is at least as effective as the semi-annual application of 38 % SDF in arresting ECC. CLINICAL SIGNIFICANCE: Silver and fluoride products are effective in arresting caries. As a simple, non-invasive, and inexpensive strategy, it can be used in young children, elderly adults, and people with special needs.

10.
Clin Cosmet Investig Dent ; 12: 493-503, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204169

RESUMO

Replacing missing teeth distal to the last standing teeth with removable partial dentures poses considerable challenge to dentists. However, the insertion of implants turns a free-end saddle into a bounded saddle. Still, patients may not be able to accept implant insertions due to financial reasons, systemic medical conditions, local anatomical factors or complicated treatments involving surgery. Hence, patients with missing teeth often prefer to use removable partial dentures to improve their dental aesthetics and to restore their oral function. In this article, we use a clinical case to illustrate the clinical procedures required for the fabrication of a distal extension denture with good retention, support, stability, aesthetics and masticatory function. We also review the design for a clasp assembly on the abutment adjacent to the distal edentulous ridge.

11.
Clin Cosmet Investig Dent ; 12: 415-422, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116910

RESUMO

The paradigms of contemporary caries management have shifted to minimal intervention dentistry. Conservative restorative procedures are recommended to replace the complete removal of all carious tissues in the management of dental caries. This article reports two clinical cases of conservative restorations of proximal caries. Different conservative cavity designs and restorative techniques were performed in the two cases. Proximal caries in posterior teeth were prepared using the box-only preparation technique or the proximal tunnel preparation technique. The cavities were restored directly with resin composites. The advantages of using the box-only preparation with fissure sealant included the maximum conservation of tooth hard tissues and the prevention of unnecessary tissue removal in the occlusal surface. The tunnel preparation preserved the marginal ridge and protected the restored tooth from fracture. The filling of composites into the tunnel demonstrated a better marginal adaptation than other restorative materials. These two techniques allowed for the preservation of more healthy dental hard tissue compared with traditional techniques. Potential problems in the restoration included the high incidence of the inappropriate removal of dental hard tissue, damage of the vital pulp and the microleakage due to the polymerization shrinkage. The solutions to minimize the risk of these problems in the operative procedures were discussed.

12.
Clin Cosmet Investig Dent ; 12: 391-397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061651

RESUMO

A well-designed removable partial denture can replace the loss of hard and soft tissues, restore masticatory function and maintain arch integrity. It is relatively simple, non-invasive and economical compared to other treatment options. Removable partial denture is therefore a common option among various treatment replacing missing teeth. A removable partial denture replacing anterior missing teeth can improve esthetics and hence the patient's quality of life. However, metal components of a removable partial denture may be visible and affects patient satisfaction. Esthetics of a removable partial denture can often be improved with some modifications to traditional designs. This article reported the use of a cobalt-chromium-based removable partial denture to replace a missing maxillary lateral incisor and molars. Palatal retentive arms were employed as the retentive components on the premolars to avoid the metal component being seen when speaking and smiling. The indications and design of the removable partial dentures with palatal retentive arms are also discussed.

13.
Clin Cosmet Investig Dent ; 12: 437-445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33122954

RESUMO

Despite global efforts to improve individuals' oral health, a considerable proportion of patients still progress to the stage in which the extractions of all teeth in one arch or both are indicated. An immediate complete denture remains a relatively accessible treatment option, particularly for those patients who cannot afford or do not need implant treatment. It is often one of the best solutions when the complete extraction of the remaining teeth is unavoidable. The denture is fitted immediately after the surgical clearance of teeth. It acts as a splint for helping with haemostasis, preventing trauma, and promoting wound healing. More importantly, an immediate denture can copy the characteristics of the existing dentition and establishes the vertical dimension of occlusion. It offers immediate replacement of the missing teeth, thereby avoiding a period of edentulism and social embarrassment. These treatments help relieve patient anxiety and bring about patient satisfaction. This study used a case report to illustrate the clinical procedures required for the construction of an immediate complete maxillary denture with good retention, support, stability, and aesthetics.

14.
Clin Oral Investig ; 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895767

RESUMO

OBJECTIVES: To investigate the associations between dental conditions, sliver diamine fluoride (SDF) application, parental satisfaction, and oral health-related quality of life (OHRQoL) of preschool children. MATERIALS AND METHODS: In a clinical trial conducted in Hong Kong, preschool children who had carious lesions into dentine were randomly assigned to receive an application of SDF solution or placebo on their caries lesions 10 weeks before they received restorations. Additionally, a random sample of caries-free children was also recruited. Parents of the study children rated their satisfaction with their child's teeth using a 5-point scale (5 = very satisfied, 1 = very dissatisfied) 10 weeks after SDF or placebo application. Besides, the Chinese version of the Early Childhood Oral Health Impact Scale (C-ECOHIS) was used to assess the children's OHRQoL. RESULTS: There were 127, 133, and 154 children in the SDF, placebo, and caries-free groups, respectively. The parents whose child had 4 or more decayed teeth reported lower satisfaction scores (mean = 2.0 ± 0.7) with their child's dental health status compared with those of parents whose child had fewer (mean = 2.6 ± 0.9) or no (mean = 3.7 ± 0.7) decayed teeth (p < 0.001). These parents also reported higher C-ECOHIS scores. However, there was no significant difference in parental satisfaction and children's OHRQoL between the SDF and placebo groups (p > 0.05). CONCLUSIONS: In this study population, parental satisfaction and children's OHRQoL were associated with children's dental caries status but not with SDF application. CLINICAL RELEVANCE: This study provides valuable information about the factors, including SDF application, that can influence parental satisfaction and OHRQoL of preschool children.

15.
J Dent ; 102: 103479, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32950631

RESUMO

OBJECTIVE: To investigate the microbiome profile and relative abundance changes of the plaque on silver diamine fluoride (SDF)-treated caries in children with early childhood caries. METHODS: A single trained examiner assessed the caries as being arrested or active and then collected plaque samples from the caries lesions from fourteen 5-year-old children immediately before, 2 weeks after, and 12 weeks after a one-off application of 38 % SDF. We assigned 16S rRNA gene sequences to operational taxonomic units (OTUs) using a 98.5 % identity cut-off. We also used a variety of taxonomy- and phylogeny-based statistical approaches to compare the biodiversity and relative abundance among different groups. RESULTS: The caries arrest rate were 90 % and 83 % after 2 and 12 weeks, respectively. We studied 46 plaque samples and identified 388 OTUs (254 identified at the species level, 129 identified at the genus level, and 76 identified at the family level). There was no significant change in the diversity in the arrested caries before and 12 weeks after SDF treatment (p = 0.71). The diversity in active caries reduced significantly 12 weeks after SDF treatment (p = 0.006). The relative abundance of certain caries-related species (e.g., Streptococcus mutans and Lactobacillus sp.) was reduced in arrested caries but was increased in active caries after SDF treatment. CONCLUSION: There was no overall microbiome changes in the caries arrested by SDF. The relative abundance of some caries-related species is reduced in arrested caries, while increased in active caries. CLINICAL SIGNIFICANCE: This study provides information on microbiome changes on SDF-treated caries of children.

16.
Artigo em Inglês | MEDLINE | ID: mdl-32784777

RESUMO

Dementia is one of the main causes of disability among elderly people. It is a progressive neurodegenerative disease that affects elderly people's ability to perform daily living activities. Alzheimer's disease is the main subtype of dementia and causes declining memory, reasoning, and communication skills. They also have behavioural and psychological symptoms, such as depression and aggression. It is essential for them to maintain good oral health, as oral health is an important and integral part of their general health. Neglecting oral health allows dental diseases to develop, and these diseases are difficult and costly to treat. However, dental diseases can be treated with ambulatory care rather than hospitalisation and emergency care. Elderly people should establish daily oral hygiene care routines during the early stages of Alzheimer's disease. They should have regular dental examinations and early minimal interventions to prevent the need for extensive and complicated procedures. Maintaining oral health becomes challenging, however, when Alzheimer's disease progresses to the middle and late stages. Because elderly people might forget or lose interest in keeping their teeth healthy, caretakers and community health workers may need to take over this task. Dentists should provide guidance on the maintenance of oral health, as the techniques used to provide this support vary depending on the elderly people concerned. The purpose of this paper is to provide an overview of oral health and the importance of oral care for elderly people with Alzheimer's disease. The paper also discusses appropriate dental interventions and techniques for maintaining good oral health and helping people with Alzheimer's to enjoy a satisfactory quality of life.


Assuntos
Doença de Alzheimer/epidemiologia , Saúde Bucal/estatística & dados numéricos , Higiene Bucal , Idoso , Doença de Alzheimer/terapia , Humanos , Higiene Bucal/métodos , Qualidade de Vida/psicologia
17.
J Dent ; 100: 103435, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32712307

RESUMO

OBJECTIVE: To compare the success rates of restoring untreated and SDF-treated dentine caries lesions in primary teeth with atraumatic restorative treatment (ART) approach. METHOD: Cavitated dentine caries lesions in preschool children were randomly allocated to two groups to be applied with either 38% silver diamine fluoride (SDF) solution or tonic water (control) ten weeks before being restored with the ART approach. Status of the restorations were assessed every six months by a blinded independent examiner. Multilevel logistic regression and multilevel survival analyses were conducted to assess the restoration success rates. RESULTS: A total of 194 children (SDF group, 101; control group, 93) were included, with 260 and 249 ART restorations placed in the SDF and the control groups, respectively. At 24-month follow-up, 88 (87 %) and 84 (90 %) children remained in the SDF and the control groups, respectively. There was no significant difference between the ART restoration success rates of the two study groups (p > 0.05). The success rate of ART restorations was associated with the class of restorations. Class I restorations had the highest success rate (∼50 %), followed by Class V (∼35 %), Class II (∼15 %) and Class III (<10 %). Besides, the mean time used to place an ART restoration in a SDF-treated caries lesion was shorter than that in untreated lesion (4.8 vs. 5.1 min, p = 0.006). CONCLUSION: Prior SDF application does not significantly affect the success rate of ART restorations placed in primary teeth. Besides, it is faster to place ART restorations in caries lesions that have been previously treated with SDF. CLINICAL SIGNIFICANCE: Prior application of silver diamine fluoride solution on cavitated dentine caries lesions in primary teeth can shorten the average time required to place an ART restoration while not jeopardizing the success rate of the restorations.

18.
Arch Oral Biol ; 117: 104833, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32682021

RESUMO

OBJECTIVES: To investigate the antibacterial effect of a new bioactive glasses on cariogenic bacteria. METHODS AND MATERIALS: A newly developed bioactive glass named Huaxi bioactive glass-ceramic (HX-BGC) and its antibacterial effects were investigated. 3 M™ Specialty Glass 19933 (SG) was used as the positive control while deionized water was used as a negative control. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of HX-BGC and SG against four cariogenic bacteria (Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilius, Lactobacillus rhamnosus) were determined by a microdilution method. Subsequently, bacterial growth and acid production were assessed by co-culturing the four cariogenic bacteria species with HX-BGC or SG at different concentrations anaerobically at 37 °C. Optical density (at 660 nm) was assessed by a microplate reader and the acidity of the supernatant was measured by a pH electrode at 6, 12, 24, and 48 h. Microbial kinetics, morphology and viability were evaluated by counting colony forming units (CFU), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM), respectively. RESULTS: The MBC of HX-BGC againstS.mutans, S.sobrinus, L.acidophilus and L.rhamnosus were 15.63 mg/mL, 15.63 mg/mL, 7.81 mg/mL and 62.5 mg/mL, respectively. The optical density (7.8 mg/mL) value of the bacterial suspensions did not change during the 48 h of culture. The acidity of bacterial suspension kept steady at around pH 8.8. Results from counting the CFU indicated that HX-BGC had stronger antibacterial effect when compare to SG, which is consistent with the SEM and CLSM results. CONCLUSIONS: HX-BGC inhibits acid production and growth of cariogenic bacteria.


Assuntos
Antibacterianos/farmacologia , Cerâmica/farmacologia , Cárie Dentária , Vidro , Cárie Dentária/prevenção & controle , Lactobacillus acidophilus , Lactobacillus rhamnosus , Testes de Sensibilidade Microbiana , Streptococcus mutans , Streptococcus sobrinus
19.
Int J Nanomedicine ; 15: 2555-2562, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368040

RESUMO

Nanotechnology has recently emerged as a rapidly growing field with numerous biomedical science applications. At the same time, silver has been adopted as an antimicrobial material and disinfectant that is relatively free of adverse effects. Silver nanoparticles possess a broad spectrum of antibacterial, antifungal and antiviral properties. Silver nanoparticles have the ability to penetrate bacterial cell walls, changing the structure of cell membranes and even resulting in cell death. Their efficacy is due not only to their nanoscale size but also to their large ratio of surface area to volume. They can increase the permeability of cell membranes, produce reactive oxygen species, and interrupt replication of deoxyribonucleic acid by releasing silver ions. Researchers have studied silver nanoparticles as antimicrobial agents in dentistry. For instance, silver nanoparticles can be incorporated into acrylic resins for fabrication of removable dentures in prosthetic treatment, composite resin in restorative treatment, irrigating solution and obturation material in endodontic treatment, adhesive materials in orthodontic treatment, membrane for guided tissue regeneration in periodontal treatment, and titanium coating in dental implant treatment. Although not all authorities have acknowledged the safety of silver nanoparticles, no systemic toxicity of ingested silver nanoparticles has been reported. A broad concern is their potential hazard if they are released into the environment. However, the interaction of nanoparticles with toxic materials and organic compounds can either increase or reduce their toxicity. This paper provides an overview of the antibacterial use of silver nanoparticles in dentistry, highlighting their antibacterial mechanism, potential applications and safety in clinical treatment.


Assuntos
Antibacterianos/farmacologia , Odontologia , Nanopartículas Metálicas/química , Prata/farmacologia , Humanos , Nanopartículas Metálicas/efeitos adversos , Nanotecnologia , Prata/efeitos adversos
20.
Int J Nanomedicine ; 15: 2829-2839, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368057

RESUMO

Objective: To investigate the remineralizing and staining effects of sodium fluoride (NaF) solution with polyethylene glycol-coated silver nanoparticles (PEG-AgNPs) on artificial dentine caries. Materials and Methods: Demineralized human dentine blocks were allocated to three groups. The blocks in group 1 underwent a topical application of a 12% silver diamine fluoride (SDF, 14,150 ppm fluoride) solution. The blocks in group 2 received a topical application of a 2.5% NaF (11,310 ppm fluoride) with PEG-AgNPs (400 ppm silver). The blocks in group 3 received deionized water. All blocks were subjected to pH cycling for 8 days. The surface morphology and cross-sectional features were investigated using scanning electron microscopy (SEM). The color parameters, crystal characteristics, lesion depth, and collagen degradation of the blocks were assessed using digital spectrophotometry, X-ray diffraction (XRD), micro-computed tomography, and spectrophotometry with a hydroxyproline assay, respectively. Results: The SEM showed that dentine collagen was exposed in group 3 but not in groups 1 and 2. The mean lesion depths in groups 1 to 3 were 118±7 µm, 121±14 µm, and 339±20 µm, respectively (groups1,2<3; p<0.001). The data indicated that fluoridated PEG-AgNPs introduced no significant color effect on dentine, but SDF caused distinct discoloration. The XRD indicated that silver chloride was formed in group 1, and fluorapatite was detected in groups 1 and 2. The concentration of hydroxyproline liberated from collagen was significantly less in groups 1 and 2 than in group 3. Conclusion: The use of NaF solution with PEG-AgNPs can remineralize artificial dentine caries and inhibit collagen degradation without causing significant tooth staining.


Assuntos
Cárie Dentária/tratamento farmacológico , Dentina/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Fluoreto de Sódio/farmacologia , Remineralização Dentária/métodos , Colágeno , Cor , Dentina/metabolismo , Dentina/patologia , Fluoretos/farmacologia , Fluoretos Tópicos/química , Fluoretos Tópicos/farmacologia , Humanos , Hidroxiprolina/metabolismo , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura , Dente Serotino/efeitos dos fármacos , Dente Serotino/patologia , Dente Serotino/ultraestrutura , Polietilenoglicóis/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Prata , Compostos de Prata/química , Compostos de Prata/farmacologia , Fluoreto de Sódio/administração & dosagem , Difração de Raios X , Microtomografia por Raio-X
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