Assessing microleakage of different class V restorations after Er:YAG laser and bur preparation

Abstract

This study assessed in vitro marginal leakage of class V cavities prepared by turbine and Er:YAG laser and restored with different materials. Sixty cavities with enamel and dentine margins were prepared and assigned to six groups: I, II, III by turbine and IV, V, VI by Er:YAG laser. The following restorative systems were used: groups I and IV: Bond 1 + Alert; II and V: Fuji II LC; III and VI: SBMP + Dispersalloy. After finishing, specimens were thermocycled for 8 h and 45 min (500 cycles), isolated, immersed in a 0.2% Rhodamine B solution, sectioned oro-facially and analysed for leakage. The dye penetration means (%) were: occlusal I: 10.09 (+/- 21.28), II: 3.25 (+/- 10.27), III: 0, IV: 41.77 (+/- 42.48), V: 23.37 (+/- 33.79), VI: 12.66 (+/- 24.06); cervical I: 16.49 (+/- 26.67), II: 4.34 (+/- 13.71), III: 0, IV: 37.71 (+/- 30.47), V: 39.56 (+/- 43.35) and VI: 72.53 (+/- 37.79). The use of Er:YAG laser for cavity preparation yielded higher degree of marginal leakage, as compared with the use of conventional air-turbine. The enamel interface provided better marginal sealing, comparing with dentine/cementum margin. As to the cavity preparation device (i.e. laser or bur), the analysis of the results showed that bonded amalgam and Fuji II LC provided less infiltration, than Alert. On the other hand, for lased cavities, Alert provided the best results, similar to those of Fuji II LC and superior to those reached by bonded amalgam.

In vitro microleakage of class v composite restorations prepared by Er,Cr:YSGG laser and carbide bur

“…When comparing microleakage between enamel and dentin margins for all groups and each one of the samples individually, dentinal margins demonstrate vastly larger amounts of dye penetration. In agreement with this observation is a summation of the published literature 1,3,8,10,12,23,[27][28][29][30]32,37,38,44,45 . This agreement can be attributed to the more difficult and technically sensitive procedure involving adhesion to dentin 8 , as well as to the more complex and reduced inorganic content of the dentin compared to enamel 1 .…”

“…The more acidic nature (pH=2) and the dual hydrophobic primer-hydrophilic resin nature of the two-step adhesive improve marginal sealing and restrict micropenetration. Despite acidic modification of dentin improves marginal sealing, microleakage remains higher for laser ablation compared to diamond bur preparation even when a separate acid-etching step is added 29 .…”

Effects of different types of adhesive systems on the microleakage of compomer restorations in Class V cavities prepared by Er,Cr:YSGG laser in primary teeth

“…Studies have shown that microleakage was greater on the gingival wall localized in dentin or cementum than on the occlusal wall 15,29) . Sidhu and McCabe 30) performed a study to compare the marginal adaptation of compomers in cervical cavities when applied with different bonding agents.…”

“…Many studies have examined the effects of erbium laser and diamond bur preparation on microleakage 14,15,29,[52][53][54][55] . Some studies found that laser irradiation exhibited same or even better microleakage outcome than did the conventional bur method [53][54][55] , but other studies had contradictory results 29,52) .…”

“…In recent years, there has been growing interest in the use of lasers for routine cavity preparation and for conditioning enamel and dentin surfaces, the latter as an alternative to conventional acid-etch methods 14) . While not a panacea for all restorative dentistry procedures, caries removal and cavity preparation with middle infrared lasers (Er:YAG and Er,Cr:YSGG) has replaced conventional high-and low-speed dental drills in many situations, providing the same clinical effectiveness with freedom from pain and discomfort by eliminating pressure, intense vibration, noise, and in most cases, the need for injected local anesthetic 15) . However, studies on surface alterations of enamel and dentin after Er,Cr:YSGG laser irradiation demonstrated microirregularities on both tissues and lack of a smear layer.…”