Journal of Endodontics Research

Examination of cytotoxicity and mutagenicity of AH26 and AH Plus sealers

I. Miletic, S. Jukic, I. Anic, D. Z_eljezic, V. Garaj-Vrhovac, M. Osmak.School of Dentistry, University of Zagreb, Croatia.Institute for Medical Research and Occupational Health, Croatia. Aim.To study in vitro the cytotoxic and mutagenic effects of AH26 and AH Plus. Conclusion.AH26 and AH Plus were shown to be cytotoxic in larger doses, while there was no mutagenicity found in both materials on human lymphocytes in highly controlled conditions in vitro.

Review of the current status of tooth whitening with the walking bleach technique

T. Attin, F. Paque, F. Ajam & A. M. Lennon Department of Operative Dentistry, Preventive Dentistry and Periodontology, Georg-August Universitat Gottingen, Gottingen, Germany. Internal bleaching procedures such as the walking bleach technique can be used for whitening of discoloured root-filled teeth. The walking bleach technique is performed by application of a paste consisting of sodium perborate-(tetrahydrate) and distilled water (3% H2O2), respectively, in the pulp chamber. Following a critical review of the scientific literature, heating of the mixture is contra-indicated as the risk of external cervical resorption and the formation of chemical radicals is increased by application of heat. An intracoronal dressing using 30% H2O2 should not be used in order to reduce the risk of inducing cervical resorption. This review provides advice based on the current literature and discusses how the walking bleach technique can lead to successful whitening of non-vital root-filled teeth without the risks of side-effects.

Healing of apical periodontitis after endodontic treatment: a comparison between a silicone-based and a zinc-oxide-eugenol based sealer

S. Huumonen, M. Lenander-Lumikari, A. Sigurdsson & D. Orstavik NIOM, Scandinavian Institute of Dental Materials, Haslum, Norway. University of Turku, Finland.University of North Carolina at Chapel Hill, USA. Aim.To assess the treatment results up to 1 year after endodontic treatment of apical periodontitis using a silicone-based sealer in comparison with Grossmanâs sealer, and to compare the results at 3 months after treatment with the 12-month follow-up to assess the prognostic value of a 3-month control. Results and conclusions.Average PAI scores decreased from 3.43 at start to 2.21 at 12 months for Grossmanâs sealer and from 3.40 to 2.26 for the silicon based material. No significant difference between the groups at start or any of the follow ups was seen. The 3-monthcontrolwas adequate in establishing significant healing in both groups. The improvement of the periapical condition continued at the12-monthexamination.

Factors influencing the fracture of nickel-titanium rotary instruments

B. Martin, G. Zelada, P.Varela, J. G. Bahillo, F. Magaan, S. Ahn & C. RodriguezDivision of Dental Pathology and Therapeutics, Department of Stomatology, School of Dentistry, University of Santiago de Compostela, Spain.Department of Computation, Faculty of Computer Science, University of A Coruna, Spain. Aim.To evaluate the effect of rotational speed and the angle and radius of curvature of root canals on the fracture of two types of nickel-titanium rotary instruments: K3 and ProTaper. Conclusions.Instrument fracture was associated with rotational speed and the angle of curvature of the canal.

Tissue reaction initiated by different sealers

M. Bernath & J. Szabo.Department of Dentistry and Oral Surgery, Faculty of Medicine, Pecs University, Pecs, Hungary. Aim.To analyse the type and degree of inflammatory reaction initiated by four sealers. Conclusions.The present study has demonstrated that sealers with different chemical compositions initiate different types of inflammatory reactions. The study revealed a good biocompatibility of Apexit and Grossmanâs sealers and emphasized that root canal filling confined to the canal is an important factor in reducing periapical inflammation.

Apoptosis: an introduction for the endodontist

P. G. Satchell, J. L. Gutmann & D. E.Witherspoon.Private Practice Limited to Endodontics, Houston, USA.Private Practice Limited to Endodontics, Dallas, USA.Private Practice Limited to Endodontics, Plano, Texas, USA. Apoptosis plays an important role in many aspects of endodontics, yet there is a paucity of information in this regard in the endodontic literature. Apoptosis is a single deletion of scattered cells by fragmentation into membrane- bound particles that are phagocytosed by other cells. It is a key process in the embryological development of the tooth, periodontal ligament and supporting oral tissue in the progression of oral disease, bone resorption, immunological response and inflammation, and in wound healing and certain pharmacological effects. The understanding of the ability of clinical materials to induce or inhibit apoptosis and the investigation of apoptosis as it relates to the pathogenesis of pulpal and periradicular pathology may eventually lead to new treatment approaches for the endodontist. The purpose of this review is to familiarize the clinical endodontist with current knowledge on apoptosis as it relates to the pulp and periradicular tissues.