Shaping of the Root Canal System: A Multistep Technique.

AIM: The aim of this scientific work is to illustrate the technique of shaping the root canal system using the multistep technique. BACKGROUND: Over time, various endodontic instrumentation techniques have been put forward, from the "step-back" technique (apical-coronal) to the "crown-down" technique (coronal-apical), the "double-flared" technique, and the most recent "single-length" technique. TECHNIQUE: The multistep technique involves six steps, one of the main objectives of these being the safety of the use of mechanical instruments with a reduction in the risk that they fracture. This technique ("mixed") provides for the use of both manual instruments in stainless steel and mechanical instruments in nickel titanium (Ni-Ti). CONCLUSION: The multistep technique is based on a standardized, flexible, and clinical protocol, which can provide for a reduction in the number of endodontic passages and instruments used and, therefore, a simplification of the operating procedure depending on both the difficulty of the root canals and the competence of the operator. CLINICAL SIGNIFICANCE: This technique is a technique for shaping the endodontic space that allows the set objectives of endodontic therapy to be reached in a predictable way with a reduced risk of iatrogenic complications.

Root canal obturation: experimental study on the thermafil system related to different irrigation protocols.

AIM: The aim of this study was to stress the ability of a specific obturation technique (thermafil technique) to seal root canal system in presence or absence of smear layer. METHODOLOGY: Sixteen monoradicular teeth, extracted for periodontal reasons, were collected for this study. All specimens were prepared with nickel-titanium rotary files, and then divided into two groups: for each group was applied a different kind of irrigation method, verifying the effectiveness in removing the smear layer, thus rendering the dentinal tubules more permeable for penetration of softened gutta-percha. Thermafil system was used to fill the root canals, and then all the specimens were observed under scanning electron microscope (SEM). RESULTS: The results showed that the Group which followed irrigation only with sodium hypochlorite exhibited significantly less gutta-percha tags when compared to the second Group, which was irrigated with sodium hypochlorite and EDTA. CONCLUSION: The thermafil systems have a very good quality of compression and fluency that permit to gain a good seal of endodontic space; furthermore it allows the penetration of gutta-percha with the formation of numerous of gutta-percha tags inside the dentinal tubules above all when smear layer is reduced or eliminated.

Resolution of endodontic issues linked to complex anatomy.

Anatomical abnormalities of the root canal system are frequently seen in specialist endodontic practice, and represent a challenge to be faced with skill and thoroughness, beginning with an accurate diagnostic phase and devising the most appropriate treatment plan. Fortunately, much progress has been made in endodontic research thanks to technological advances and the evolution of higher performance instruments, which now consent even very complex cases to be resolved with relative ease. Below are described the salient features of recent progress in endodontics, along with a description of several clinical cases in which the operator has encountered numerous difficulties due to peculiar tooth morphology, overcome successfully thanks to the application of modern tools and consolidated clinical experience in the field.

Innovations in endodontic filling materials: guttapercha vs Resilon.

One of the goals of endodontic treatment is to achieve a complete, tridimensional, hermetic sealing of the root canal system to prevent the entry of microorganisms or their products through both the coronal and apical pathways. Gutta-percha is the most widely used material for root canal filling and despite its numerous properties, such as biocompatibility and thermoplasticity, it has however an important limit: the lack of adhesion to the canal walls. Attempts to address this problem have been made over the years by using endodontic cements capable of bonding to canal dentine but their tendency to resorption in time can compromise the quality of treatment. The first step towards a real adhesive endodontic filling(4) is rather recent; in fact, it goes back to 2003 when, on the occasion of the American Dental Association (ADA) Annual Session, Resilon Research LLC introduced a new canal filling adhesive system based on a thermoplastic synthetic resin material called Resilon™. The real innovation of this system is its capacity of creating a core made of Resilon™ bonded to the cement which adheres to dentine walls previously conditioned with a self-etching primer(4) so no changes in the techniques of canal preparation are required. The aim of this study was to evaluate the capacity of two filling materials (gutta-percha and Resilon) to adapt to the canal anatomy, especially on the apical third, using the continuous wave of condensation technique. Our data suggest that in the third apical the gutta-percha best shows rheological properties that are as important as the bond capability.

Mozart: the toothache of a genius.

The medical history of Wolfgang Amadeus Mozart (1756-1791) has been pieced together from his letters and from anecdotes, but his dental health is one aspect which has been somewhat overlooked. It is known that, from an early age, he suffered from toothache and tooth abscesses, problems that may even have had other medical repercussions. In this paper, the authors explore and consider whether these negative experiences might have influenced Mozart's work and his attitude to teeth and dental pathologies. Two pieces of evidence from the life and work of this great composer provide clues: the aria entitled "A tooth decayed and sensitive to cold" (KV 209 a) (1772), containing the lament of a "sick man" suffering from toothache; and the first of the "Zoroastrian Riddles," which Mozart proposed during a masked ball in 1786, and whose solution is "teeth." Close examination of these two creative feats demonstrate that Mozart's attitude toward dental pathologies was calm and rational, so much so that he even managed to use the topic as a source of inspiration for a small jewel of a composition.

Not just two million teeth: Giovanni Battista Orsenigo, monk dentist.

Brother Giovanni Battista Orsenigo, a monk of the "Ospitalieri di San Giovanni di Dio--Fatebenefratelli" holy order, was the most famous dental surgeon in Rome from 1870 to the start of the 20th century, but it was his nomination in 1972 by the Guinness Book of Records as the "most dedicated dentist", having kept more than 2 million extracted teeth, that brought him international reknown. Orsenigo was not merely a tooth-drawer, but a truly great dentist, and one who honored the code of his monastic order. It is important that this distinguished colleague, who is not mentioned in international dental literature, be restored to dental history and that his memory be preserved.