Heat treatment following surface silanization in rebonded tribochemical silica-coated ceramic brackets: shear bond strength analysis.

OBJECTIVE: This study aimed to evaluate the effects of heat treatment on the tribochemical silica coating and silane surface conditioning and the bond strength of rebonded alumina monocrystalline brackets. MATERIAL AND METHODS: Sixty alumina monocrystalline brackets were randomly divided according to adhesive base surface treatments (n=20): Gc, no treatment (control); Gt, tribochemical silica coating + silane application; Gh, as per Gt + post-heat treatment (air flux at 100ºC for 60 s). Brackets were bonded to the enamel premolars surface with a light-polymerized resin and stored in distilled water at 37ºC for 100 days. Additionally, half the specimens of each group were thermocycled (6,000 cycles between 5-55ºC) (TC). The specimens were submitted to the shear bond strength (SBS) test using a universal testing machine (1 mm/min). Failure mode was assessed using optical and scanning electron microscopy (SEM), together with the surface roughness (Ra) of the resin cement in the bracket using interference microscopy (IM). 2-way ANOVA and the Tukey test were used to compare the data (p>0.05). RESULTS: The strategies used to treat the bracket surface had an effect on the SBS results (p=0.0), but thermocycling did not (p=0.6974). Considering the SBS results (MPa), Gh-TC and Gc showed the highest values (27.59±6.4 and 27.18±2.9) and Gt-TC showed the lowest (8.45±6.7). For the Ra parameter, ANOVA revealed that the aging method had an effect (p=0.0157) but the surface treatments did not (p=0.458). For the thermocycled and non-thermocycled groups, Ra (µm) was 0.69±0.16 and 1.12±0.52, respectively. The most frequent failure mode exhibited was mixed failure involving the enamel-resin-bracket interfaces. CONCLUSION: Regardless of the aging method, Gh promoted similar SBS results to Gc, suggesting that rebonded ceramic brackets are a more effective strategy.

Heat treatment following surface silanization in rebonded tribochemical silica-coated ceramic brackets: shear bond strength analysis

OBJECTIVE: This study aimed to evaluate the effects of heat treatment on the tribochemical silica coating and silane surface conditioning and the bond strength of rebonded alumina monocrystalline brackets. MATERIAL AND METHODS: Sixty alumina monocrystalline brackets were randomly divided according to adhesive base surface treatments (n=20): Gc, no treatment (control); Gt, tribochemical silica coating + silane application; Gh, as per Gt + post-heat treatment (air flux at 100ºC for 60 s). Brackets were bonded to the enamel premolars surface with a light-polymerized resin and stored in distilled water at 37ºC for 100 days. Additionally, half the specimens of each group were thermocycled (6,000 cycles between 5-55ºC) (TC). The specimens were submitted to the shear bond strength (SBS) test using a universal testing machine (1 mm/min). Failure mode was assessed using optical and scanning electron microscopy (SEM), together with the surface roughness (Ra) of the resin cement in the bracket using interference microscopy (IM). 2-way ANOVA and the Tukey test were used to compare the data (p>0.05). RESULTS: The strategies used to treat the bracket surface had an effect on the SBS results (p=0.0), but thermocycling did not (p=0.6974). Considering the SBS results (MPa), Gh-TC and Gc showed the highest values (27.59±6.4 and 27.18±2.9) and Gt-TC showed the lowest (8.45±6.7). For the Ra parameter, ANOVA revealed that the aging method had an effect (p=0.0157) but the surface treatments did not (p=0.458). For the thermocycled and non-thermocycled groups, Ra (µm) was 0.69±0.16 and 1.12±0.52, respectively. The most frequent failure mode exhibited was mixed failure involving the enamel-resin-bracket interfaces. CONCLUSION: Regardless of the aging method, Gh promoted similar SBS results to Gc, suggesting that rebonded ceramic brackets are ...

Efeito Cluster em implantes dentários / Cluster effect on dental implants

O objetivo desta revisão fundamentou-se em pesquisar o efeito do efeito cluster em implantes dentários osseointegráveis visando obter informações clínicas e científicas sobre este fenômeno. Implantes dentais osseointegráveis têm demonstrado uma ascensão em sua utilização clínica nos últimos anos. Trata-se de uma opção para reabilitar pacientes que apresentam dentes ausentes, considerando os aspectos funcionais e estéticos. Altos índices de falha de implantes dentais parecem estar concentrados em grupos específicos de indivíduos, sugerindo que a resposta do hospedeiro pode modular o sucesso dos implantes. A concentração das perdas de implantes, denominada clusterização, pode indicar uma resposta imunoinflamatória do hospedeiro. Falhas relacionadas aos implantes dentais é um traço complexo que pode envolver vários fatores etiológicos. O conhecimento da etiologia e de fatores associados à falha de implantes pode ajudar no reconhecimento nos pacientes de risco e auxiliar o desenvolvimento de um tratamento adequado em conjunto com estratégias de prevenção

This review was based on research the effect of cluster effects in osseointegrated dental implants in order to obtain clinical and scientific information about this phenomenon. Osseointegrated dental implants have shown a rise in its clinical use in recent years. This is an option to rehabilitate patients with missing teeth, considering the functional and aesthetic aspects. High rates of failures of dental implants seem to be concentrated in specific groups of individuals, suggesting that the host response may modulate the success of implants. The concentration of lost implants, called clustering, may indicate a host immunoinflammatory response. A failure related to dental implants is a complex trait that can involve multiple etiological factors. The knowledge of the etiology and factors associated with implant failure can help us in recognizing patients at risk and help develop an appropriate treatment in conjunction with strategic prevention