A zinc oxide-modified hydroxyapatite-based cement favored sealing ability in endodontically treated teeth.

OBJECTIVES: To evaluate the effectiveness of different endodontic canal sealers for dentin permeability reduction and to determine the viscoelastic performance of root dentin after their application. METHODS: Cervical, medial and apical root dentin surfaces were treated with two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite); an epoxy resin- based canal sealer, AH Plus; and gutta-percha. Root dentin was evaluated for fluid filtration. Field emission scanning electron microscopy, energy dispersive analysis, AFM, Young's modulus and Nano-DMA analysis were also performed, at the inner and outer zones of dentin. RESULTS: Dentin treated with oxipatite showed the lowest microleakage among groups with hermetically sealed tubules and zinc-based salt formations. Samples treated with oxipatite showed the highest Ei at the cervical dentin third among groups, at 6 m of storage. Oxipatite promoted the highest complex modulus and tan delta values at the inner zone of both cervical and medial root dentin. Calcypatite favored the lowest tan delta outcomes at the inner zone of apical dentin at 6 m. CONCLUSIONS: Specimens treated with oxipatite showed the highest sealing ability, based on the highest Young's modulus and dentin mineralization, achieved by closing dentinal tubules, voids and pores that reinforced the inner zone of root dentin. The homogeneity of viscoelastic properties among the different root dentin thirds favored the energy dissipation without creating zones of stress concentration and micro-cracking which would have challenge micropermeability. Thereby, among the tested materials oxipatite is proposed as canal filling material and sealer in endodontics. CLINICAL SIGNIFICANCE: Oxipatite could be considered a good candidate for root canal filling material and sealer due to its improved long-term sealing ability and to the advanced remineralization, and so to the enhanced energy dissipation achieved at the inner zone of the radicular dentin.

Measurement of dental implant stability by resonance frequency analysis: A review of the literature

Dental implant treatment is an excellent option for prosthetic restoration that is associated with high successrates. Implant stability is essential for a good outcome. The clinical assessment of osseointegration is based onmechanical stability rather than histological criteria, considering primary stability (absence of mobility in bonebed after implant insertion) and secondary stability (bone formation and remodelling at implant-bone interface).The aim of this study was to review the literature on Resonance Frequency Analysis (RFA) as a methodfor measuring dental implant stability. An online search of various databases was conducted on experimentaland clinical research published between 1996 and 2008. The studies reviewed demonstrate the usefulness ofRFA as a non-invasive method to assess implant stability. Further research is required to determine whetherthis system is also capable of measuring the degree of dental implant osseointegration (AU)

Effect of chlorhexidine-thymol varnish on root caries in a geriatric population: a randomized double-blind clinical trial.

OBJECTIVES: Little is known about the effect of Cervitec, a chlorhexidine-thymol varnish, on root caries. Our objective was to determine whether a 3-monthly application of Cervitec over 1 year would limit the progress of existing root caries lesions and reduce the incidence of dental root caries in a group of dentate institutionalized elderly, as a complement to their usual oral hygiene practices. METHODS: A double-blind randomized clinical trial was conducted in 68 subjects (34 per group) in two residences in Almería (Spain). Twenty-one subjects with 60 root caries lesions and 25 with 65 lesions, in the Cervitec and placebo groups, respectively, completed the study. Varnishes were applied twice in the first week, 1 month later, and every 3 months until the end of the study. Clinical parameters associated with established lesions were determined at baseline and after 6 and 12 months, as was the incidence of root caries lesions. RESULTS: The clinical evolution of lesions was significantly better in the Cervitec group as opposed to the placebo group in terms of width, height, color, and texture. The increase in root caries was significantly lower (p=0.039) in the Cervitec group. CONCLUSION: According to these results, Cervitec may help to control established root lesions and reduce the incidence of root caries lesion among institutionalized elderly.

Estudio de microfiltración con nuevos materiales alternativos para el sector posterior / Microlakeage study of new posterior filling materials

Fundamento: recientemente, se han comercializado una serie de materiales como los composites condensables, ormoceras y los denominados materiales inteligentes con la finalidad disminuir algunos de los inconvenientes más graves que presentan los composites convencionales. Material y Método: el propósito de nuestro estudio ha sido comparar la filtración marginal de restauraciones de clase II MOD, obturadas con materiales representativos de cada grupo. Grupo 1: Prime & Bond NT.- SureFil, Grupo 2: Ariston Liner- Ariston pHc, Grupo 3: One Coat Bond- Synergy, Grupo 4: One-Step- Pyramid y Grupo 5: Etch & Prime3.0- Definite. Las muestras se termociclaron, y se almacenaron en azul de metileno al 2 por ciento, durante 7 días a 37º C. Después de ser seccionados longitudinalmente, se evaluó la microfiltración mediante observación con lupa estereoscópica a 10x. Resultados: El análisis estadístico indica que no existen diferencias significativas en la filtración entre los grupos 3, 4 y 5, pero estos tres grupos sí presentan diferencias significativas respecto a los dos restantes: 1 y 2, que muestran mayores tasas de filtración. Conclusiones: la filtración en los grupos obturados con Prime & Bond- SureFil y Ariston Liner- Ariston pHc es significativamente mayor que en los grupos en que se utilizó One Coat Bond- Synergy, One-Step- Pyramid y Etch & Prime3.0- Definite. (AU)

Influencia de programas públicos de salud oral en los esolares sobre la demanda privada de Odontología Restauradora / Influence of public oral health schoolchildren programmes on private restorative dentistry demand

lntroducción:(fundamento y objetivo): El objetivo es analizar la influencia de algunos programas públicos odontológicos sobre la demanda de odontología restauradora privada. Métodos: En el curso 96/97 se inició un ensayo de campo en Granada, con cuatro grupos ce escolares de 6-7 anos de edad Sellador (aplicados en el Centro de Salud, n=121), Sellador+Flúor (+ barniz de flúor en los colegios, n=119), Flúor (n=137) y Con-trol (n-95). Todos fueron explorados al inicio, y a los 6 meses. Se analiza el incremento de odontología restauradora privada, a través del índice cie restauración (dientes obturados del total de dientes cariados + obturados). Resultados y conclusiones El índice de restauración aumentó significativamente en los cuatro grupos. El incremento medio (- desviación estándar) de obturaciones 2s mayor en los grupos Sellador (0.54-1 1 57) y Sellador+Flúor (0.55+-1.27), que en los grupos Flúor (0.23 0.99) y Control (0.19ñ0 80), no habiendo diferencias significativas de incremento entre los grupos Sellador +Flúor y Sellador, ni entre Flúor y Control. Se concluye que un programa de selladores desde un centro de salud produce un incremento de la demanda de odontología restauradora, pero no un programa de flúor tópico profesional (barniz) realizado en el colegio (AU)