Study on the inhibition and remineralization of enamel demineralization by polydopamine in vitro / 口腔疾病防治

Objective@#To investigate the inhibitory effect of polydopamine (PDA) on enamel demineralization in isolated teeth and the induction of hydroxyapatite (HA) production on the surface of demineralized enamel to provide a novel protocol for the prevention and treatment of enamel demineralization. @*Methods@#Twenty isolated bovine teeth were cut into 20 enamel slices and randomly divided into an experimental group and a control group, with 10 slices in each group. The enamel slices in the experimental group were immersed in 2 mg/mL freshly prepared dopamine solution and incubated for 24 hours at room temperature in the dark to prepare the PDA coating, while the control group was left untreated. Then, the isolated bovine teeth, with and without PDA coating, were immersed in artificial demineralization solution at 37 °C for 3 days, followed by 7 days in simulated body fluid (SBF), and the immersion solution was changed daily. The surface morphology of enamel was observed by scanning electron microscopy (SEM), the calcium/phosphorus ratio of the enamel surface was analyzed by energy dispersive spectroscopy (EDS), and the characteristic functional groups in enamel deposits were analyzed by Fourier transform infrared spectroscopy (FTIR).@* Results@#Compared with the control group, the number of demineralized pores produced after 3 d of enamel demineralization with polydopamine coating was less, and the diameter was smaller. EDS elemental analysis showed that the Ca/P ratio after enamel demineralization was 2.37 in the experimental group, which was smaller than the 2.53 ratio in the control group. In the remineralization experiment, after 7 days of remineralization of PDA coated enamel in the experimental group, lamellar grains were produced on the enamel surface, and the growth showed obvious directionality, growth regularity and uniform arrangement. In the control group, the surface of enamel was flocculent mineral deposit, and the crystallinity was poor. The FTIR results proved that the enamel surface deposit of PDA-coated enamel was HA after 7 d of remineralization. @*Conclusion @#PDA can affect the nucleation process of HA and promote the production of HA on the surface of demineralized enamel.

Photo Catalytic Silver Modified Orthodontic Brackets - An Innovative Method for Prevention of White Spot Lesions

Association between fixed orthodontic therapy and enamel decalcification causing periodontal disease and enamel decalcification is a known problem of orthodontic treatment. The root cause of this is the fact that brackets provide an ideal environment for bacteria to accumulate and multiply. Hence modifying the surface of brackets with some photocatalytic antibacterial substance could help in prevention of this side-effect. The current study was thus planned to evaluate the anti-adherence of bacteria to photocatalytic silver coated brackets for the prevention of white spot lesions. METHODSAfter obtaining ethical clearance from the institutional ethics committee, 40 metal brackets of upper central incisor were taken. These brackets were divided into group 1 & group 2 each containing twenty brackets. Group 1 (control group) consisted of plain metal brackets while group 2 (experimental group) consisted of silver coated brackets. Both the groups were subjected to laboratory bacterial tests to assess the bacterial adhesion to brackets and then statistical analysis was done to obtain results. RESULTSSilver modified brackets showed around 25 % less adhesion of bacteria as compared with plain brackets. CONCLUSIONSModifying orthodontic brackets by coating them with photocatalytic silver could prove to be an innovative and effective method in prevention of white spot lesions after fixed orthodontic therapy.

The in vitro remineralizing effect of CPP-ACP and CPP-ACPF after 6 and 12 weeks on initial caries lesion

Abstract Objective: The aim of this in vitro study was to determine the effects of remineralization promoting agents containing casein phosphopeptide-stabilized amorphous calcium phosphate (CPP-ACP), or CPP-ACP in combination with fluoride (CPP-ACPF) on artificial white spot lesions (WSLs) after 6 and 12 weeks. Methodology: White spot lesions were created on 123 sectioned premolars (246 specimens) with a demineralization solution during a 96 hours pH-cycling regime. Two experimental groups were created: a CPP-ACP group (Tooth Mousse™), and a CPP-ACPF group (Mi Paste Plus™). Additionally, two control groups were created, one using only a conventional toothpaste (1450 ppm fluoride) and another one without any working agents. All teeth were also daily brushed with the conventional toothpaste except the second control group. Tooth Mousse™ and Mi Paste Plus™ were applied for 180 seconds every day. The volume of demineralization was measured with transverse microradiography. Six lesion characteristics regarding the lesion depth and mineral content of WSLs were also determined. Results: The application of CPP-ACP and CPP-ACPF had a significant regenerative effect on the WSLs. Compared to Control group 1 and 2 the volume of demineralization after 6 weeks decreased significantly for CPP-ACP (respectively p<0.001 and p<0.001) and CPP-ACPF (respectively p=0.001 and p=0.003). The same trend was observed after 12 weeks. For the CPP-ACPF group, WSL dimensions decreased significantly between 6 and 12 weeks follow-up (p=0.012). The lesion depth reduced significantly after application of CPP-ACP and CPP-ACPF but increased significantly in the Control groups. Mineral content increased for CPP-ACP and CPP-ACPF after an application period of 12 weeks, but this was only significant for CPP-ACP. Conclusions: Long-term use of CPP-ACP and CPP-ACPF in combination with a conventional tooth paste shows beneficial effects in the recovery of in vitro subsurface caries lesions.

Ação da própolis de apis mellifera associada ao fluoreto de sódio sobre o biofilme dental: ensaio clínico duplo cego randomizado / The effect of apis mellifera propolis associated with sodium fluoride on dental biofilm: randomized double-blind clinical trial

Objetivo: Avaliar a ação do Extrato Etanólico de Própolis 5% isoladamente e combinado ao fluoreto de sódio sobre o acúmulo do biofilme dental, e conseqüentemente, sobre a atividade de cárie. Material e Método: Nesse ensaio clínico duplo cego randomizado, participaram 97 escolares, os quais foram aleatoriamente divididos em Grupo I e Grupo II, sendo submetidos, respectivamente, à aplicação tópica do Gel A (Própolis 5% + NaF 0,05%) e do Gel B (Própolis 5%). A contagem dos níveis salivares de Streptococcus mutans, o acúmulo de biofilme (IHO-S) e a quantificação das manchas brancas ativas foram analisados antes e após a aplicação dos géis experimentais. Resultados: Ambos os géis suprimiram as contagens salivares de Streptococcus mutans e o acúmulo do biofilme dental, sem diferenças estatisticamente significantes entre os grupos, enquanto somente o Gel A fora capaz de inativar significativamente as manchas brancas. Conclusão: A própolis associada ao fluoreto de sódio foi eficiente na redução do acúmulo de biofilme e dos níveis salivares de Streptococcus mutans, tendo destacada ação na remineralização de manchas brancas.

Purpose: the aim of this study was to evaluate the effect of this substance both individually and combined with sodium fluoride on dental biofilm accumulation and consequently on caries activity. Material and Method: Ninety seven pupils participated in this randomized double-blind clinical trial. Subjects were randomly divided into Group I and Group II and submitted to topical applications of Gel A (5% Propolis + 0.05% NaF) and Gel B (5% Propolis), respectively. The salivary count of Streptococcus mutans, biofilm accumulation (OHI-S) and the quantification of active white spots were analyzed before and after the applications of both gels. Results: The two gels suppressed the salivary count of Streptococcus mutans and accumulation of dental biofilm, where no statistically significant difference between the groups was observed. However, only Gel A was able to significantly inactivate white spots. Conclusion: Propolis associated with sodium fluoride was efficient in reducing the accumulation of biofilm and the salivary levels of Streptococcus mutans, while demonstrating a notable effect on the remineralization of white spots.

Lesiones incipientes de caries dental y su relación con la higiene bucal en niños venezolanos / Incipient lesions of dental caries and its relation to oral hygiene in Venezuelan children

Se realizó un estudio observacional descriptivo de corte transversal con la finalidad de identificar la prevalencia de lesiones incipientes de caries dental (LIC) y su relación con la higiene bucal en niños de 5-11 años del Área de Salud Integral Comunitaria (ASIC) Macandona, Municipio Maracaibo del Estado de Zulia en Venezuela, en el periodo de enero a diciembre de 2006. El universo fue de 220 niños, de entre ellos se seleccionaron 120 que asistieron a la consulta en el periodo establecido y cumplieron con los criterios de inclusión. Las LIC se detectaron por el método clínico visual-tàctil sin presión, el nivel de higiene bucal por índice de higiene bucal revisado y el antecedente de cepillado con flúor se obtuvo al interrogar a los padres. La medida resumen de datos fue el porcentaje y se empleó la prueba de diferencia de proporciones. El 33,3 por ciento de los niños presentó dos LIC, de ellos el 60,7 por ciento correspondió al sexo femenino; el 42,9 por ciento de los niños con 2 LIC mostró higiene bucal inadecuada y los que utilizaron dentífricos fluorados diariamente estaban menos afectados. Ello permite concluir que más de la mitad de los niños presentaron LIC, y que las lesiones incipientes fueron màs frecuentes en el sexo femenino, en los niños con deficiente higiene bucal, y en los que no utilizaban dentífricos fluorados diariamente(AU)

A cross-sectional, descriptive and observational study was conducted to identify the prevalence of dental caries incipient lesions (CIL) and its relation to oral hygiene in children aged 5-11 of Community Integral Health Area (CIHA) in Macandona municipality, Zulia State, Venezuela from January to December, 2006. Sample included 220 children selecting 120 seen in consultation during the established period and fulfilling the inclusion criteria. The CILs were detected by visual/tactile clinical method without pressure, the oral hygiene level by revised oral hygiene rate and the background of fluorine brushing was achieved by asking parents. The abstract measure of data was the percentage and we used the ratio difference test. The 33,3 percent of children had two CILs, from then the 60,7 percent was a female sex; the 42,9 percent of children with two CILs showed a inappropriate oral hygiene and those used daily fluorine toothpaste were less involved. It allows us to conclude that the half of children had CIL, and that the incipient lesions were more frequent in female sex, in children with a poor oral hygiene, and in those no used fluorine toothpaste daily(AU)

White spots: manchas blancas en el esmalte asociadas a tratamiento ortodoncico con aparatologia fija: [revisión] / White spots: associated to enamel lesion after orthodontic treatment

Uno de los problemas del tratamiento ortodoncia es el mantenimiento de una adecuada higiene oral del paciente. La aparatología fija ortodóncica predispone al aumento y acumulación de la placa y la desmineralización del esmalte lo cual puede manifestarse pocas semanas después de colocada la aparatología. La evidencia clínica mas temprana es la aparición de una mancha blanca opaca en el esmalte que preocupa al ortodoncista y al paciente debido a que es una lesión potencialmente irreversible, no saludable y antiestética. La presente revisión bibliografica describe algunos de los métodos para la prevención de las manchas blancas en el esmalte sean aplicados por el ortodoncista o por el paciente.

During Orthodontics treatment one of the biggest patients´ problem is to maintain an adequate oral and dental hygiene to keep good Oral/Dental Health. Fixed orthodontics devices predispose dental plaque accumulation on oral tissues and dental surfaces. Plaque accumulation on dental surfaces can lead to enamel demineralization. This condition is frequently detected few weeks after orthodontic device fixation. Earliest clinical evidence of dental demineralization are White and Opaque spots on dental enamel that always worries both: the Orthodontics and the patient. White spots could be irreversible, and non-aesthetic lesions that need to be prevented or treated.

Clinical and Endoscopic Analysis of Juvenile Polyps / 대한소화기내시경학회지

BACKGROUND: This study was undertaken to review cases of juvenile polyps with respect to clinical and endoscopic features. METHODS: Of the 544 cases of colonoseopic polypectomies performed from Jan. 1 to Jan. 1997, 14 cases(2.6%) involved juvenile poiyps. Those 14 cases were analyzed with special consideration given to colonoscopic aspects. RESULTS: The most common age groups were the fifth and the sixth decades, comprising 50%. There were two children below 10 years of age. Males were predominant in the ratio of 1.3:1. Rectal bleeding was the most common symptom, and 4 cases were asymptomatic. Mediumsized(6~10 mm) polyps were the most common, 7 eases(50%), and large(> 1 cm) polyps were the next most common, 5 cases(35.7%). The first predilection of site was the rectum, 8 cases(57.1%); the second was the sigmoid colon with 5 cases(35.7%). Grossly, pedunculated polyps were the largest in number, accountieg for 64.3% of the cases; the others were all subpedunculated. In 9 cases(64.3%), the preoperative macroscopic diagnoses were consistent with the final diagnoses; in the other cases, the polyps were initially diagnosed as being adenomatous. Adenomatous and inflammatory polyps were associated with 3 cases, who were all men. White spots were noticed around the polyp base in 4 cases (28.6%); the clinical significance of those should be investigated further. All 14 patients underwent polypectomy by endoscopic snare resection without any complications. CONCLUSIONS: Colonoscopy should be the main tool for diagnosis and treatment of juvenile polyps. Juveoile polyps should be taken into account in cases of rectal bleeding and need to be differentiated from adenomatous polyps. Endoscopic polypectomy is an adequate procedure for the treatment of a solitary juvenile paiyp.