Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2016-08-30, 09:39:09 | version 1.38.0
14 Dental Tribune United Kingdom Edition | 7/2016 TRENDS & APPLICATIONS www.dental-tribune.com The Dental Tribune International Magazines Shipping Address Name Address Zip Code, City Country E-mail Date, Signature PayPal Credit Card Credit Card Number Expiration Date Security Code CAD/CAM Clinical Masters* cosmetic dentistry** implants laser ortho** roots Journal of Oral Science & Rehabilitation*** Fax: +49 341 48474 173 E-mail: subscriptions@dental-tribune.com EUR 44 per year (4 issues per year; incl. shipping and VAT for customers in Germany) and EUR 46 per year (4 issues per year; incl. shipping for customers outside Germany). * EUR 12 per year (1 issue per year; incl. shipping and VAT for customers in Germany) and EUR 14 per year (1 issue per year; incl. shipping for customers outside Germany). ** EUR 22 per year (2 issues per year; incl. shipping and VAT for customers in Germany) and EUR 23 per year (2 issues per year; incl. shipping for customers outside Germany). *** EUR 200 per year (4 issues per year; incl. shipping and VAT). Your subscription will be renewed automatically every year until a written cancellation is sent to Dental Tribune International GmbH, Holbeinstr. 29, 04229 Leipzig, Germany, six weeks prior to the renewal date. I would like to subscribe to SUBSCRIBE NOW! AD direction. The retro-prepared canal was irrigated with 2 per cent chlor- hexidine, followed by sterile sa- line with irrigation micro-cannu- las (Angelus). The canal was dried using aspiration micro-cannulas on a vacuum pump, leaving it ready to receive the retrograde obturation material. The canal was retro-obturated with white MTA (Angelus). The placement of the MTA in the retro- grade cavity was done with the MAP System (Roydent) and ret- ro-condensed until the canal was completely filled (Fig. 12). In order to prevent the growth of the con- nective tissue inside the apical bone cavity, it was filled with sur- gical calcium sulphate (GMReis). The postoperative control radi- ographs were taken after 72 hours (Figs. 13–15), six months (Fig. 16) and 12 months (Fig. 17). On the last radiograph, it was possible to see the advanced repair of the bone in the apical region. Discussion The use of operating micros- copy in combination with ultra- sonic tips and MTA-based bioac- tive retrograde obturation materi- als has increased the success rates of endodontic microsurgery from 60 per cent to levels above 90 per cent. The enhanced visibility pro- vided by the microscope allows for evaluation of microstructures and details that are not visible to the naked eye. It allows the micro- surgeon to refine his or her motor precision.15 Trauma to the delicate periodontal and periapical tissue can be minimised, leading to bet- ter aesthetic results. The osteotomy needed for ac- cess to the apical third had tra- ditionally been performed with chisels or drills and high rotation. In the 1980s, piezo-osteotomy was finally introduced.16 In this surgi- cal method, the osteotomy is done with ultrasound, which has techni- cal and biological advantages over the use of drills at high or low rota- tion. Ultrasound is safe, as it only works on mineralised tissue. It pre- serves soft tissue, such as nerves, blood vessels and mucosa. The am- plitude of its micro-movements varies between 60 and 210 µm, al- lowing for precise cuts into hard tissue, such as bone and tooth. With the use of ultrasound, acoustic micro-currents in the op- erating field are formed that clear the surgical area by improving haemostasis.16–19 The ultrasonic en- ergy acts on cellular viability in the region operated on, accelerating the first postoperative phases of the bone repair process. The faster increase of bone morphogenetic protein, modulation of the inflam- matory reaction and the stimula- tionofthe formation ofosteoblasts are physiological benefits that con- tribute to this improved and faster healing process.17 The apicectomy must be per- formed at 3 mm from the root apex, thus maintaining the length of the dental root, as well as elimi- nating the majority of the apical ramifications and lateral canals.20 The rotational movement of drills or vibrational movement of ultra- sound during the apicectomy dislodges the remaining gutta- percha and this often leads to mis- alignment of gutta-percha with the walls of the canal. This is one of the reasons for the combination of the retrograde preparation and later retrograde obturation. In addition, during the retrograde preparation, removal of the in- fected dentine and the obturation material and cleaning of the isthmus is done, optimising the intra-canal bacterial control and shaping of the canal and leaving it prepared for the sealing material. A retrograde cavity must be at least 3 mm in depth inside the root canal along its long axis.20 If this cannot be achieved, the out- come of the proposed cleaning and disinfection, as well as the prognosis of the treatment, will be uncertain. In the microsurgical technique, the retrograde prepa- ration is always done with ultra- sonic tips because it is the only way to achieve preparations of 3 mm or more into the root canal. This is possible owing to the long neck of the ultrasonic tips in addi- tion to a sequence of three to four bends along its length. These bends allow the active tip to gain full accessibility to the root canal. The ultrasonic tips also allow for non-circular movements for better mechanical cleaning of flat areas of the root canals, known as isthmuses. It is possible to observe the elliptical preparation with greater vestibular-lingual exten- sion of the original anatomy of the microanatomy of the medial root. ” Page 16 “ Page 12 Fax: +4934148474173