Clinical and microbiologycal analysis of endodontic treatment failure

Abstract

The aim of endodontic treatment is to eliminate the infection from the root canal, to prevent reinfection and to prevent the possible occurrence of periapical periodontal inflammation by three-dimensional hermetic obturation. After appropriate completion of the treatment, it is expected periapical lesions healing and the reduction or disappearance of the radiolucency over time. The most common reasons that lead to the failure of endodontic treatment are complicated anatomy of the root canal system, inadequate control of infection, complications during endodontic treatment in the form of perforation or fracture of the root canal instruments , inadequate instrumentation and obturation, and microleakage of temporary or definitive coronal restoration. Sometimes failure can occur when the endodontic treatment correctly conducted and all procedures are fully satisfied. The reason for this is the complex anatomy of the canal system and the numerous ramifications and anastomoses between the main and accessory canals that can not be adequately treated nor obturated by contemporary instruments, materials and techniques as well. Region of endodontic space that couldn’t be reached can contain bacteria and necrotic tissue even when it seems that the canal obturation is correct on intraoral X-ray. The microbiological status of endodontically treated teeth is significantly different compared to untreated infected root canal. Only a few bacterial species was found in the canals of teeth with adequate endodontic treatment and persistent asymptomatic apical periodontal inflammation. These are mainly Grampositive cocci, bacilli and filaments with an equal distribution of facultative and obligate anaerobes. Techniques of cultivation of bacteria and PCR analysis identified Enterococcus, and Streptococcus, Actinomyces then, Peptostreptococus, Propionibacterium (previously Arachnia) and Lactobacillus. There are some extraradicular factors that could adversely affect the postoperative healing of periapical lesions...

Cilj endodontskog tretmana je da eliminise infekciju iz kanala korena, da prevenira reinfekciju i trodimenzionalnom hermetičkom obturacijom spreči eventualnu pojavu zapaljenja apikalnog parodoncijuma. Nakon adekvatno sprovedenog tretmana, očekuje se zalečenje odnosno zarastanje periapikalne lezije i smanjenje ili iščezavanje rasvetljenja tokom vremena. Najčešći razlozi koji vode neuspehu endodontskog lečenja su komplikovana anatomija kanalnog sistema, neadekvatna kontrola infekcije, komplikacije tokom endodontskog tretmana u vidu perforacije korena ili frakture kanalnih instrumenata, neadekvatna instrumentacija i obturacija kanala, odnosno mikrocurenje privremenih ili definitivnih koronarnih restauracija. Ponekad se neuspeh može javiti i onda kada je endodontska terapija korektno vodjena i sve procedure u potpunosti ispoštovane. Razlog za to je kompleksna anatomija kanalnog sistema i brojne ramifikacije i anastomoze izmedju glavnog i akcesornih kanala koje se ne mogu adekvatno obraditi niti obturisati postijećim instrumentima, materijalima i tahnikama. Neinstrumentirane regije endodontskog prostora mogu sadržati bakterije i nekrotično tkivo čak i onda kada se čini da je opturacija kanala radiografski korektna. Mikrobiološki status endodontski lečenih zuba se značajno razlikuje u odnosu na netretirani inficirani kanal korena. Pronađeno je svega nekoliko bakterijskih vrsta u kanalima zuba sa adekvatnim endodontskim tretmanom i perzistirajućim asimptomatskim zapaljenjem apeksnog parodoncijuma. To su uglavnom Gram-pozitivne koke, bacili i filamenti sa jednakom distribucijom fakultativnih i obligatnim anaeroba. Tehnikama kultivisanja bakterija i PCR-analizom identifikovani su Enterococcus i Streptococus, zatim Actinomyces, Peptostreptococus, Propionibacterium (ranije Arachnia) i Lactobacillus...