Er:YAG Laser and Fractured Incisor Restorations: An In Vitro

Introduction. The aim of this study was to analyse the effects of an Er:YAG laser on enamel and dentine in cases of dental restorations involving fractured teeth, utilizing the dental fragment. Materials and Methods. Seventy-two freshly extracted bovine incisors were fractured at the coronal level by using a hammer applied with a standardized method, and the fragment was reattached by using three different methods: Er:YAG laser, orthophosphoric acid, and laser plus acid. The different groups were evaluated by a test realized with the dynamometer to know the force required to successfully detach the reattached fragment and by a microinfiltration test by using a 0.5% methylene blue solution followed by the optic microscope observation. Results. The compression test showed only a slight difference between the three groups, without any statistical significance. The infiltration test used to evaluate the marginal seal between the fracture fragment and the tooth demonstrated that etching with Er:YAG laser alone or in combination with orthophosphoric acid gives better results than orthophosphoric acid alone, with a highly significant statistical result. Discussion. Reattaching a tooth fragment represents a clinically proven methodology, in terms of achieving resistance to detachment, and the aim of this work was to demonstrate the advantages of Er:YAG laser on this procedure. Conclusion. This “in vitro” study confirms that Er:YAG laser can be employed in dental traumatology to restore frontal teeth after coronal fracture

Radiation absorption in different kinds of tissue analysis: ex vivo study with supercontinuum laser source

With the introduction of more and more new wavelengths, one of the main problems of medical laser users was centered on the study of laser-tissue interactions with the aim of determining the ideal wavelength for their treatments. The aim of this ex vivo study was to determine, by means of the utilization of a supercontinuum source, the amount of transmitted energy of different wavelengths in different organ samples obtained by Sprague Dawley rats. Supercontinuum light is generated by exploiting high optical non-linearity in a material and it combines the broadband attributes of a lamp with the spatial coherence and high brightness of laser. Even if the single transmission measurement does not allow us to separate out the respective contribution of scattering and absorption, it gives us an evaluation of the wavelengths not interacting with the tissue. In this way, being possible to determine what of the laser wavelengths are not useful or active in the different kinds of tissue, physicians may choose the proper device for his clinical treatments

Welding in the dental office by fiber delivered laser: a new technique.

OBJECTIVE: The aim of this study is to demonstrate the ability of dentists to weld different metals during daily practice using a fiber-delivered laser normally used for dental surgery, and to evaluate the possibilities offered by this new technique. BACKGROUND DATA: Laser welding is a common technique that has long been used in dental technician laboratories. It has many advantages over conventional techniques: it may be applied directly to master casts, and it avoids damage to the acrylic or ceramic portions close to the welded area. In addition, it may be applied on different types of metallic alloys, and it may provide a stronger attachment than other more traditional techniques. The cost, size, and limited flexibility of laser transmission systems using fixed lenses have restricted their use to dental technician laboratories. MATERIALS AND METHODS: The authors detail their experience with welding using an Nd:YAG fiberoptic-delivered laser that is normally used for dental therapy. RESULTS: This work describes some clinical cases that demonstrate the ease of use of this technique to weld broken appliances for both prosthetic and orthodontic therapy. CONCLUSION: Dentists using this technique can carry out immediate restoration of metallic fixed, removable, and orthodontic broken prostheses in their own offices, thus reducing the time needed for such repairs

Er:YAG Laser: A New Technical Approach to Remove Torus Palatinus and Torus Mandibularis.

Objective. The aim of this study was to assess the ability of Er:YAG laser to remove by excision torus mandibularis and to smooth torus palatinus exostosis. Materials and Methods. Torus mandibularis (TM) and torus palatinus (TP) were surgically eliminated via the Er:YAG laser using the following parameters: TM: output power ranging from 500 to 1000 mJ, frequency from 20 to 30 Hz, sapphire tips (diameter 0.8 mm), air-water spray (ratio 5/5), pulse duration 150 μsec, fluence ranging from 99592 J/cm(2) to 199044,586 J/cm(2). TP: a peeling technique was used to eliminate TP, as excision by slicing being impossible here. Results. TM: excision was obtained after 12730 pulses. TP: smoothing technique took more time compared with excision. Once peeling was considered to be accomplished, the use of a surgical rasp was necessary to eliminate bone spicules that could delay the wound to heal in good conditions. Conclusion. Er:YAG excision (TM) or Er:YAG peeling (TP) are safe clinical techniques easy to practice even if the time required for excision or surface smoothing is more than the time required with bony burs and high speed instruments

Laser welding and syncristallization techniques comparison: in vitro study.

Introduction. The aim of this study was to analyse the effects of an Er:YAG laser on enamel and dentine in cases of dental restorations involving fractured teeth, utilizing the dental fragment. Materials and Methods. Seventy-two freshly extracted bovine incisors were fractured at the coronal level by using a hammer applied with a standardized method, and the fragment was reattached by using three different methods: Er:YAG laser, orthophosphoric acid, and laser plus acid. The different groups were evaluated by a test realized with the dynamometer to know the force required to successfully detach the reattached fragment and by a microinfiltration test by using a 0.5% methylene blue solution followed by the optic microscope observation. Results. The compression test showed only a slight difference between the three groups, without any statistical significance. The infiltration test used to evaluate the marginal seal between the fracture fragment and the tooth demonstrated that etching with Er:YAG laser alone or in combination with orthophosphoric acid gives better results than orthophosphoric acid alone, with a highly significant statistical result. Discussion. Reattaching a tooth fragment represents a clinically proven methodology, in terms of achieving resistance to detachment, and the aim of this work was to demonstrate the advantages of Er:YAG laser on this procedure. Conclusion. This "in vitro" study confirms that Er:YAG laser can be employed in dental traumatology to restore frontal teeth after coronal fracture