Management of large class II lesions in molars: how to restore and when to perform surgical crown lengthening?

The restoration of endodontic tooth is always a challenge for the clinician, not only due to excessive loss of tooth structure but also invasion of the biological width due to large decayed lesions. In this paper, the 7 most common clinical scenarios in molars with class II lesions ever deeper were examined. This includes both the type of restoration (direct or indirect) and the management of the cavity margin, such as the need for deep margin elevation (DME) or crown lengthening. It is necessary to have the DME when the healthy tooth remnant is in the sulcus or at the epithelium level. For caries that reaches the connective tissue or the bone crest, crown lengthening is required. Endocrowns are a good treatment option in the endodontically treated tooth when the loss of structure is advanced.

Combined sodium hypochlorite and 940 nm diode laser treatment against mature e. faecalis biofilms in-vitro

Laser irradiation has been introduced in endodontic treatment due to its bactericidal effect. The aim of this study is to evaluate the bactericidal efficacy of a 940 nm diode laser alone or in combination with 5% sodium hypochlorite [NaOCl] against mature biofilms of E. Faecalis. Sixty-eight [60 for the three groups, 4 for SEM and 4 as negative controls] single-rooted human central incisors were prepared and contaminated with E. Faecalis. After two weeks of incubation, specimens were randomly divided in three groups; group 1 [n =20], the teeth were irradiated with a 940 nm diode laser; group 2 [n=20], specimens were rinsed with 5% NaOCl; group 3 [n=20], the teeth were rinsed with 5% NaOCl and then were irradiated with 940 nm diode laser. Four teeth were used to observe the biofilms by SEM. Intracanal bacteria sampling was done, and the samples were plated to determinate the CFU count. At 24 hours and 7 days, group 3 showed a significant difference [P=0,02; P=0,00] in disinfection if compared to group 1 but did not show this difference if compared to group 2 [P=1, P=0,66], although group 3 obtaining a more extensive disinfection. Groups 1 and 2 did not show difference after 24 hours [P=0,09] but showed a significant difference 7 days afterwards [P=0,04]. The combination of sodium hypochlorite and diode laser light [940 nm] has a synergistic effect, intensifying the bactericidal action.