Complications in endodontic therapy

Pravilno izvedena endodontska terapija omogućava očuvanje i održavanje funkcije zu-ba koji bi inače bio izgubljen. Preduvjeti za uspješnu endodontsku terapiju su: postav-ljanje dobre dijagnoze, kvalitetna i jasna rendgenska snimka, bez koje se ne bi smjelo početi sa endodontskom terapijom, pravilan trepanacijski otvor i pravocrtan pristup ka-nalima, pravilan odabir instrumenata te tehnike rada, kako bi se spriječile komplikacije kao što su formiranje stube i stvaranje umjetnog kanala. Proceduralne nezgode koje se nisu dale predvidjeti ili spriječiti javljaju se u malom postotku i kod pravilnog rada, što dovodi do neuspjeha terapije. Potrebno ih je pravovremeno uočiti i adekvatno sanirati. Zalomljeni instrumenti u korijenskom kanalu predstavljaju veliki izazov za kliničara. Za-lomljeni instrument se može pokušati ukloniti, zaobići (bypass) ili se kanal može obraditi i napuniti do mjesta zalomljenog instrumenta. Postupak je sličan onom pri nastanku stube u kanalu. Čeličnim instrumentima #6, #8 i #10 premosti se zalomljeni instrument i pokuša se postići prvobitna radna duljina. Prije vađenja zalomljenog fragmenta, kanal treba biti pripremljen te osiguran pravilan koronarni pristup zalomljenom instrumentu, što se postiže upotrebom dijamantnih svrdala različitih duljina i promjera.(27) Zatim se pristupa vađenju ultrazvučnim kanalnim instrumentima, ekstirpatorima ili Hedstrom pilicama, ultrasoničnim instrumentima ili raznim specijaliziranim setovima za vađenje instrumenata (Masseran set). Ukoliko nijedna od prethodno navedenih tehnika nije uspjela, kanal koronarno od zalomljenog fragmenta se instrumentira i puni. Kako bi se spriječilo lomljenje instrumenata u kanalu nužno je poznavanje fizičkomeha-ničkih svojstava, kontrolirana uporaba sile i redovito pregledavanje korištenih instrume-nata uz odbacivanje oštećenih. Također je potrebno korijenski kanal stalno podmazivati tijekom čišćenja i obrade radi smanjenja trenja zagrijavanja i opterećenja instrumenata. Prognoza liječenja kod ovakvih proceduralnih nezgoda ovisi o vremenu kada je došlo do loma instrumenta i stupnju infekcije kanala.(27)Properly conducted endodontic therapy ensures that the tooth function is preserved and kept which would otherwise be lost. Pre-conditions for a successful endodontic therapy are: to make a good diagnosis , good quality and clear x-ray without which no endodontic thera-py should be started, correct trepanation hole and linear access to canals, correct choice of instruments and work techniques in order to prevent complications such as ledge forming or creating an artificial canal. Procedural accidents that could not be predicted or prevented occur in a small percentage even when you work properly, leading to the failure of a thera-py. It is necessary to spot them on time and repair adequately. Fractured instruments in the root canal are a real challenge for the clinician. They can be removed, bypassed or the canal can be processed and filled up to the position of the fractured instrument. The procedure is similar to the one which is applied when a ledge appears in the canal. The fractured instru-ment is bridged with steel instruments #6, #8 and #10 and one should try to achieve the original working length. Before the fractured instrument is extracted the canal has to be prepared and the proper coronal access to the fractured instrument ensured. This can be achieved using diamond drills of various lengths and diameters.(26) After that ultrasonic canal instruments, extirpators or Hedstrom files, ultrasonic instruments or various specialized sets for extraction of instruments are used (Masseran set). If none of the mentioned techniques has given results, the canal coronary to the fractured fragment is instrumented and filled. In order to prevent fracture of instruments in the root canal it is necessary to knnow physical and mechanical properties and to limit the use of force. One should also check the used in-struments regularly and discard the damaged ones. It is also necessary to lubricate the root canal constantly during cleaning and treatment in order to prevent friction, heating and the overload of instruments. The treatment prognosis with such procedural accidents depends on the time when the frac-ture happened and the grade of canal infection