Intentional replantation and Biodentine root reconstruction. A case report with 10-year follow-up.

AIM: To describe the innovative use of intentional replantation for Biodentine root reconstruction of a previously treated immature maxillary central incisor with vertically extended crown root fracture and root detachment. SUMMARY: In the present case, the intentional replantation of a failing, previously treated maxillary central incisor with a vertical crown/root fracture in a 12-year-old male patient is reported. The gross extrusion of gutta-percha points beyond the apex and the pre-existing extensive, trauma related, distal cervical dentinal detachment justified the intentional replantation treatment plan as an option for tooth retention. After controlling the infection by oral administration of antibiotics, the immature tooth was extracted atraumatically and kept in gauze embedded with tooth replantation medium. The apical third of the immature fractured tooth was treated with ultrasonics and an MTA plug (MTA Angelus White, Londrina, Brazil). The distal cervical dentinal root defect was reconstructed with Biodentine (Septodont, St. Maur-des-Fosses, France). The tooth was reinserted and stabilized to the adjacent teeth for 2 weeks. The total extraoral time before replantation was 25 min. In the 10 years since the initial trauma (9 years after the intervention) radiographic and clinical evaluation revealed uneventful healing of the periapical lesion, normal mobility and no detectable signs of external replacement resorption. KEY LEARNING POINTS: Intentional replantation may provide a viable treatment alternative in cases of severe complicated crown/ root fractures Biodentine may be useful in the reconstruction of external root defects in crown root fractured traumatic dental injuries.

Root canal treatment of a dilacerated mandibular premolar using a novel instrumentation approach. A case report.

AIM: To report on a novel method to instrument a dilacerated double-curved mandibular premolar. SUMMARY: A 45-year-old female was referred suffering from diffuse pain emanating from the mandibular right quadrant. The second premolar (tooth 45) was diagnosed with symptomatic irreversible pulpitis. The radiographic examination revealed a dilacerated S-shaped root configuration, with 2 severe curvatures of <2 mm radius. Under local anaesthesia and rubber dam isolation, a glide path was created until a size 10 K-file reached working length. Instrumentation to larger size was achieved with a novel approach using controlled memory files. The controlled memory files were pre-curved and passively inserted below the curvature until maximum frictional resistance. The motor was activated by maintaining light apical pressure, and the files were withdrawn from the canal. This procedure was repeated until each file could reach the working length. Chemical disinfection was achieved with positive syringe irrigation of 6% NaOCl, followed by 17% EDTA rinsing and manual dynamic gutta-percha activation of the irrigants. Canal filling was achieved using the continuous wave of condensation technique and thermoplasticized injectable gutta-percha backfill. The postoperative radiography revealed that the initial canal anatomy of the dilacerated double-curved root canal was preserved.

The use of a single-step regenerative approach for the treatment of a replanted mandibular central incisor with severe resorption.

AIM: To report the clinical and radiographic treatment outcome of an immature replanted mandibular incisor with severe inflammatory external root resorption following a single-step regenerative approach. SUMMARY: A 7-year-old female patient was referred 1 week following an extrusion injury to her mandibular central incisor (tooth 31). There was a history of a 6 months previous avulsion injury to the same tooth, which had been replanted after 20 min of extra-oral time. On clinical examination, all teeth were asymptomatic and there was an arch wire splint placed on the mandibular incisors. Radiographic examination revealed severe inflammatory external root resorption of tooth 31. A diagnosis of necrotic pulp and asymptomatic apical periodontitis was made. Under local anaesthesia and rubber dam isolation, an access cavity was prepared. The canal was irrigated using 6% NaOCl solution delivered through the EndoVac negative pressure irrigation system (Endo Vac, Axis/SybronEndo, Coppell, TX, USA). A 17% EDTA solution was used for 5 min followed by a final rinse of sterile water. The periapical tissues were probed using a K-file, and bleeding was induced. A blood clot was allowed to form filling the entire canal. A thick plug of MTA was placed in direct contact with the blood clot. The tooth was restored with composite resin. All procedures were performed in a single visit. The splint was removed 2 weeks later. Recall examination after 24 months revealed healthy soft tissues with normal periodontal probing and mobility. The 24 months radiographic evaluation revealed healing of the severe inflammatory external root resorption and continuous root development/dentine wall thickening of the apical third. No signs of ankylosis or significant discoloration was present.

The use of MTA/blood mixture to induce hard tissue healing in a root fractured maxillary central incisor. Case report and treatment considerations.

AIM: To report the use of MTA/blood mixture for the induction of hard tissue healing of multiple horizontal root fractures in a maxillary incisor. SUMMARY: An 18-year-old male patient was referred after suffering trauma to the anterior maxilla. Radiographic evaluation revealed multiple horizontal fractures in the middle and cervical third of his maxillary right central incisor. Clinical evaluation revealed third grade mobility of the coronal segment. The patient's accompanying radiographs revealed that root canal treatment of all segments had been previously initiated and both segments had been rendered pulpless. The coronal segment was repositioned and stabilized. A bi-antibiotic mixture, containing equal parts of ciprofloxacin and metronidazole, was used for the disinfection of the root canal segments. A blood clot was induced from the periapical area and MTA powder was mixed with the blood creating a bioceramic mixture covering all the fractures. Thick MTA was placed as a coronal barrier and the tooth was restored. Recall examination after 24 months revealed healing of the horizontal fractures. The MTA mixed with the blood lost its radio-opacity over time. Tooth mobility returned to normal limits. KEY LEARNING POINTS: A low range of 5-25% of all horizontally root fractured cases develop pulp necrosis, confined in the coronal segment, leaving the apical segment with vital tissue. In the unfortunate situation that the pulp of both segments becomes necrotic or the entire pulp tissue is removed, the use of MTA/blood mixture may be beneficial for the induction of hard tissue healing. MTA when mixed with blood seems to lose its radio-opacity over time.

Computational study of pulsatile blood flow in prototype vessel geometries of coronary segments.

The spatial and temporal distributions of wall shear stress (WSS) in prototype vessel geometries of coronary segments are investigated via numerical simulation, and the potential association with vascular disease and specifically atherosclerosis and plaque rupture is discussed. In particular, simulation results of WSS spatio-temporal distributions are presented for pulsatile, non-Newtonian blood flow conditions for: (a) curved pipes with different curvatures, and (b) bifurcating pipes with different branching angles and flow division. The effects of non-Newtonian flow on WSS (compared to Newtonian flow) are found to be small at Reynolds numbers representative of blood flow in coronary arteries. Specific preferential sites of average low WSS (and likely atherogenesis) were found at the outer regions of the bifurcating branches just after the bifurcation, and at the outer-entry and inner-exit flow regions of the curved vessel segment. The drop in WSS was more dramatic at the bifurcating vessel sites (less than 5% of the pre-bifurcation value). These sites were also near rapid gradients of WSS changes in space and time - a fact that increases the risk of rupture of plaque likely to develop at these sites. The time variation of the WSS spatial distributions was very rapid around the start and end of the systolic phase of the cardiac cycle, when strong fluctuations of intravascular pressure were also observed. These rapid and strong changes of WSS and pressure coincide temporally with the greatest flexion and mechanical stresses induced in the vessel wall by myocardial motion (ventricular contraction). The combination of these factors may increase the risk of plaque rupture and thrombus formation at these sites.

Illness and cures in the Greek propitiatory inscriptions and dedications of Lydia and Phrygia.

The propitiatory inscriptions of Lydia and Phrygia (of the second and third centuries AD) manifest the belief that illness is a divine punishment for a sin (usually for a religious offence); cure can thus be achieved through expiation. Although scientific medicine was not unknown, the high costs of doctors, the belief in the omnipotence of gods, and the attribution of illness to divine intervention led the villagers to the local sanctuaries, where they received instructions by means of dreams and oracles. Some priests had medical experience, but they usually practised a 'religious healing' (incantations, purifications, sacrifices, the ritual transfer of the sin and the illness to animals).