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rev port estomatol med dent cir maxilofac . 2019;60(3):130-136 131

Efeito do condicionamento de superfície e do uso de elixires orais
na resistência adesiva de compósito reparado

r e s u m o

Palavras-chave: Objetivos: O objetivo deste estudo foi avaliar o efeito de elixires orais na microdureza Knoop
Resistência adesiva na superfície de compósito, e avaliar a influência do contato com elixires orais e condicio-
Resina composta namento mecânico na resistência ao corte de resinas compostas reparadas.
Microdureza Métodos: Cento e vinte espécimes de resina composta (GrandioSO) foram preparados e di-
Elixires orais vididos aleatoriamente em 4 grupos experimentais, de acordo com o elixir utilizado (água
Reparação destilada; Listerine Dentes & Gengivas; Eludril Perio; Lacer Ouros). Após um período de 5
dias em água (37ºC), durante os quais foram submetidos a 12 ciclos de 2 horas de imersão
no respetivo elixir, foi determinada a microdureza Knoop. Em seguida, cada grupo foi divi-
dido em 3 subgrupos com base no condicionamento mecânico da superfície do compósito
(sem tratamento; jateamento com 50 µm Al2O3; abrasão com broca diamantada) e, após o
protocolo de reparação (Solobond M e GansdioSO), os espécimes foram submetidos a testes
de resistência a tensões de corte. Os dados foram analisados usando ANOVA seguido por
testes post-hoc segundo SKN (α=0,05).
Resultados: O grupo de espécimes envelhecidos em água destilada apresentou uma maior
dureza que os demais grupos experimentais (p<0,05). Não foram encontradas diferenças
estatisticamente significativas (p>0,05) entre os demais grupos. Nem o contacto com elixir
(p=0,214), nem o condicionamento mecânico de superfície (p=0,165) tiveram efeito signifi-
cativo sobre a resistência adesiva.
Conclusões: Apesar da dureza do compósito ter sido afetada negativamente pelo contato
com os elixires orais utilizados neste estudo, a resistência adesiva do composto reparado
não foi afetada. (Rev Port Estomatol Med Dent Cir Maxilofac. 2019;60(3):130-136)
© 2019 Sociedade Portuguesa de Estomatologia e Medicina Dentária.
Published by SPEMD. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/).

the prepared defect, allowing the preservation of part of the
Introduction
9
original restoration. This technique is more conservative, sim-
The use of composite resins in restorative dentistry has sig- ple and time-saving. 8,11,12 Several studies have demonstrated
nificantly increased over the last years, due to the rising de- the good clinical performance of repaired restorations, includ-
mand for esthetic dental restorations and the improvement ing life spans similar to new restorations, thus making the
of physical and chemical properties of these materials. 1-3 repair a valid treatment option. Nevertheless, replacement of
However, composite resins have a limited life-span due to defective restorations still is the most common treatment in
clinical variables related to patients and materials, and also general dental practice. 8,13
to the quality and technique of the operator. 3-6 In the repair approach, the material of the original resto-
The main reasons reported for restorations failure are sec- ration, which was exposed to the oral environment, may have
ondary caries, fracture of the filling or the tooth itself, margin- undergone several changes in its surface and structure that
al deterioration, loss of anatomic form, wear, discoloration and may influence the success of a subsequent repair. 14-17 Mouth-
6,7
pigmentation. After the first 7 years in function, half of the washes, which often have a high alcohol content and a low pH,
composite resin restorations are estimated to require clinical can contribute to this degradation process and consequently
intervention, and the clinician may choose to replace or repair to the reduction of the mechanical properties of the repaired
them. 2,8 composite restoration. 18,19
Replacement of defective restorations represents the ma- Knowing that the bond strength between an old compos-
jor part of restorative dentistry in general dental practice and ite and a new composite is frequently lower than the cohe-
consists in the removal of the entire restoration followed by sive strength of the material, the prior mechanical and/or
9
the placement of a new one. When a restoration is replaced, chemical conditioning of the surface of the aged composite
there is a loss of healthy dental tissue, increasing the size of has been proposed to increase the bond strength between the
the cavity to restore. 8,10 Furthermore, this technique is more two increments. 15,20-23 Nevertheless, the relationship be-
time-consuming and costly, and more likely to cause damage tween the repair bond strength and the surface changes re-
to the pulp. 7,11 sulting from aging and/or applied treatments remains un-
Repair consists in the removal of part of the restoration clear, and there is no consensus on the results obtained with
together with the localized defect, followed by repairing only different procedures.