Effect of different root caries treatments on the sealing ability of conventional glass ionomer cement restorations

Abstract

In this study we compared the microleakage of conventional glass ionomer cement (GIC) restorations following the use of different methods of root caries removal. In vitro root caries were induced in 75 human root dentin samples that were divided in five groups of 15 each according to the method used for caries removal: in group 1 spherical carbide burs at low speed were used, in group 2 a hand-held excavator was used, and in groups 3 to 5 an Er,Cr:YSGG laser was used at 2.25 W, 40.18 J/cm 2 (group 3), 2.50 W, 44.64 J/cm 2 (group 4) and 2.75 W, 49.11 J/cm 2 (group 5). The air/water cooling during irradiation was set to 55%/65% respectively. All cavities were filled with GIC. Five samples from each group were evaluated by scanning electron microscopy (SEM) and the other ten samples were thermocycled and submitted to a microleakage test. The data obtained were compared by ANOVA followed by Fisher's test (p≤0.05). Group 4 showed the lowest microleakage index (56.65 6.30; p<0.05). There were no significant differences among the other groups. On SEM images samples of groups 1 and 2 showed a more regular interface than the irradiated samples. Demineralized dentin below the restoration was observed, that was probably affected dentin. Group 4 showed the lowest microleakage values compared to the other experimental groups, so under the conditions of the present study the method that provided the lowest microleakage was the Er,Cr:YSGG laser with a power output of 2.5 W yielding an energy density of 44.64 J/cm 2 .

Glass Ionomer Cements for the Restoration of Non-Carious Cervical Lesions in the Geriatric Patient

“…The conditioner should be applied and removed with attention so the dentin is not over-dried [ 6 ]. Although conditioning is unnecessary when the sclerotic dentin is removed with laser irradiation, this alternative method of preparation should be avoided because RMGI interacts very superficially with laser-irradiated dentin, adversely influencing the bonding efficacy of RMGI [ 4 , 26 ]. Besides the elimination of the smear layer, some studies suggest that enamel should be edge beveled in order to allow the glass ionomer to have adequate thickness at the margins, which compensate for its low fracture strength [ 7 , 10 ].…”

“…Diminished function of the salivary gland and reduced unstimulated salivary flow is another important issue leading to dryness of the mouth and xerostomia. All these conditions combined with a chronic disease background, medication and the inability to perform adequate oral hygiene could lead patients to experience severe oral problems, including high levels of dental caries, and difficulties in chewing, eating and communicating [ 3 , 4 , 12 , 24 ].…”

“…Nowadays, the number of people regarded as older adults or as elderly is rapidly increasing [ 3 ]. Due to preventative dentistry and higher life-span, the maintenance of teeth of the elderly has seen significant growth [ 4 ]. This fact, along with changes in the human diet, has multiplied the prevalence of non-carious cervical lesions in older people [ 5 ].…”

The combined use of Er,Cr:YSGG laser and fluoride to prevent root dentin demineralization

“…For the acid challenge, samples were submitted to a pHcycling procedure, modified from previously described protocols 13 , 14 . The demineralization solution (pH=4.3) consisted of 2 mmol/L of Ca and 2 mmol/L of phosphate in buffer solution of acetate 0.075 mol/L, and the remineralization solution (pH=7.0) consisted of 1.5 mmol/L of Ca, 0.9 mmol/L of phosphate and 150 mmol/L of potassium chloride.…”