Books

Rotary root canal instruments manufactured from nickel-titanium alloy have proved to be a valuable adjunct for root canal therapy. Over the past two decades, instrument design has been considerably modified; progress has been made in manufacturing, as well as alloy processing. Clinical procedures and ideal working parameters are still being refined as new instruments continue to be introduced to the market. This review is intended to summarize clinical and laboratory findings for several current instruments. Some guidelines and usage parameters are also detailed. Keywords: nickel-titanium, root canal anatomy, root canal preparation, shaping

Prior to root canal therapy, the pulp chamber needs to be accessed to allow mechanical preparation and chemical disinfection of the root canal system. An optimised access facilitates safe and effective endodontic therapy; however, errors during access, in particular over-preparation and under-preparation, may cause problems in subsequent procedures. Detailed understanding of normal anatomy and its variations is imperative and needs to be supplemented with a thorough analysis of the particular case being treated. Odontogenesis and the deposition of tertiary dentine play an important role in determining the location and extent of the penetration into the pulp chamber, as well as the location and trajectory of the coronal root canal portion. High- and slow-speed handpieces with a set of burs along with dedicated hand instruments have been used for endodontic access for decades. More recently, the increasingly widespread addition of the operating microscope and ultrasonically powered instruments has improved the chances of locating orifices, removing mineralisation and optimising access cavities. Locating all present orifices is crucial to the preparation of all canals, and straight-line access, including removal of restrictive coronal dentine and shaping of the coronal third of the root canal, is important for the successful use of nickeltitanium rotary instruments. This review presents the knowledge base and clinical guidelines for safe and efficient access cavity preparation. Keywords: anatomy, endodontic access, instruments, procedural errors

Aim: To review relevant ethical principles in dentistry and relate them to endodontic practice. Summary: In dentistry, as in other areas of healthcare, the clinician has to deal with various legal and ethical issues. Whilst legal issues are often discussed, comparatively little is known about the ethical issues that govern a clinician's actions. In this article, an attempt is made to clarify the distinctions between ethical principles and legal rules, and to highlight their relationship. In general, five main ethical principles in dentistry have been outlined: autonomy, non-maleficence, beneficence, veracity and justice. Since there are specific ethical issues in daily endodontic practice (such as informed consent to endodontic treatment, the increasing use of implants instead of root canal treatment and the relationship between oral and general health), an attempt is made to co-relate these general principles to endodontics. Additional discussion and examples are suggested including guidelines on decision-making based on ethical principles. Key learning points: • Endodontic treatment is governed by ethical and legal principles. • The foundations for both law and ethics were laid out in ancient times but are constantly modified by society. Keywords: endodontics, ethics, principles

Unbehandelte endodontische Infektionen führen sehr oft zur Entwicklung von apikalen Läsionen. Die zahnerhaltende Therapie der Wahl ist dann eine Wurzelkanalbehandlung. Auch ein dentales Trauma kann eine Wurzelkanalbehandlung notwendig werden lassen; bei beiden Diagnosen wird über hohe Erfolgsraten berichtet. Dieses Ergebnis kann aber durch ungünstige Folge- oder Begleiterscheinungen wie Zahnverfärbung zunichte gemacht werden, was von den Patienten zunehmend weniger toleriert wird. Im vorliegenden Beitrag wird der Verlauf zweier Fälle mit Zahnverfärbungen und intrakoronalem Bleichen geschildert. In einem Fall steht der ästhetische Anspruch im Vordergrund, während im zweiten Fall eine weitergehende chirurgische Behandlung erforderlich war. Es werden Behandlungsabläufe und mögliche Komplikationen des internen Bleichens diskutiert, insbesondere das Auftreten externer Resorptionen. Im zweiten vorgestellten Fall wurde eine solche externe Resorption mit einem mikrochirurgischen Eingriff behandelt. Abschließend wird ein klinisches Konzept für das interne Bleichen vorgestellt. Keywords: Internes Bleichen, Trauma, zervikale Resorption