RO0111

06 I I special _ laser _The main goals of endodontic treatment are theeffectivecleaningoftheroot-canalsystem.Tradi- tional endodontic techniques use mechanical instru- ments,aswellasultrasoundandchemicalirrigationto shape,cleanandcompletelydecontaminatetheendo- dontic system. The complexity of the root-canal system is well known. Numerous lateral canals, of various dimen- sionsandwithmultiplemorphologies,branchofffrom the principal canals. A recent study found complex anatomical structures in 75% of the teeth analysed. The study also found residual infected pulp after the completion of chemo-mechanical preparation, both in the lateral canals and in the apical structures of vitalandnecroticteethassociatedwithperi-radicular inflammation.1 The effectiveness of the debridement, cleaning and decontamination of the intra-radicular space is limited, given the anatomical complexity and the inability of common irrigants to penetrate into the lateral canals and the apical ramifications. Therefore, itappearsadvisabletosearchfornewmaterials,tech- niques and technologies that can improve the clean- ing and decontamination of these anatomical areas. The use of lasers in endodontics has been studied since the early 1970s, and lasers have been more widely used since the 1990s.2–7 In this regard, Part I of this article will describe the evolution of laser techniques and technologies. The second part, which will be published in roots 2/2011, will present the state-of-the-art effectiveness of these instruments in the cleaning and decontamination of the endo- dontic system and take a look at the future, present- ing recent preliminary studies on new methods of utilising laser energy. _Lasers in endodontics Laser technology was introduced to endodontics with the goal of improving the results obtained with traditional procedures through the use of light energybyincreasingcleaningabilityandtheremoval ofdebrisandthesmearlayerfromtherootcanalsand also improving the decontamination of the endo- dontic system. Different wavelengths have been shown to be effectiveinsignificantlyreducingbacteriaininfected canals and studies have confirmed these results in vitro.8 Further studies have demonstrated the Fig. 1_Lasers and the electro- magnetic spectrum of light. roots1_2011 Laser in endodontics (Part I) Authors_ Prof Giovanni Olivi, Prof Rolando Crippa, Prof Giuseppe Iaria, Prof Vasilios Kaitsas, Dr Enrico DiVito & Prof Stefano Benedicenti, Italy & USA Fig. 1