| True | False |
| Risk for perforations is greater in teeth with calcified (obliterated) pulp chamber and canals than in normal |
| Improper use of instruments is a common cause for perforations |
| Flexible files with non-cutting tip cannot cause apical perforations |
| Presence of an infection may reduce prognosis of perforation treatment |
| Above (coronally to) marginal bone level, composite materials must be considered in perforation treatment |
| As MTA is mixed with water, it is sensitive to additional moisture at the perforation site |
| Composite materials are sensitive to moisture |
| Instrument fracture is a potential problem only with NiTi instruments |
| Instrument fracture is a potential problem only with steel instruments |
| Instrument fracture is usually a result of faults in the manufacturing process |
| Hedstroem files fracture easier in filing than in rotary motion |
| Both small and large diameter instruments may fracture |
| Instrument fracture always reduces the prognosis of the treatment |
| It is not always necessary to remove the fractured instrument |
| Instrument fracture is potentially more harmful in pulpitis than in a necrotic tooth with apical periodontitis |
| The patient must always be informed about the fracture and its possible consequences |
| Specially designed, titan or steel ultrasound tips are useful for removal of fractured instruments |
| If the fractured instrument cannot be removed, surgery is always indicated |
| True | False |
| Pulp space becomes gradually smaller during ageing |
| Calcification of the root canal is an indication for endodontic treatment |
| Canal obliteration always results in apical periodontitis |
| Only necrotic teeth may get calcified canals |
| Formation of secondary dentine is the only possible cause for disappearance of the pulp space |
| Revascularization often results in the development of osteoid tissue in the root canal |
| Chronic pulpitis typically speeds up calcification process |
| When the pulp cannot be detected in the radiograph, it cannot be found and instrumented clinically |
| Secondary dentine filling the previous canal space has a darker color than surrounding dentine. |
| Small K-files must be used only with a filing (up-down) motion |
| Small K-files must be used only with a balanced force technique |
| Only very light force needs to be used with small K-files |
| Small K-files in calcified canals must be used with a combination of balanced force and filing |
| Fiber optic light can be very useful to help to locate calcified canals |
| Operative microscope is an invaluable tool to locate difficult cases of calcified canals |
| True | False |
| Overinstrumentation may result in bleeding into the canal |
| Overinstrumentation of ca 1 mm may sometimes help drainage of pus through the root canal in acute apical periodontitis |
| Multifrequency apex locators are not reliable for determining WL |
| Overinstrumentation never increases risk for overfilling |
| Overinstrumentation always increases risk for overfilling |
| Use of silicone stoppers may help to prevent overinstrumentation |
| WL radiograph is important in preventing overinstrumentation |
| Overinstrumentation may result in destruction of the natural apical foramen |
| True | False |
| Overfilling with sealer is a typical cause of severe, post-treatment pain |
| Sealer surplus will always be resorbed from the periapical tissues by host cells |
| Too small master GP cone may be one reason for overfilling |
| In cases of open apex, apexification may be advisable to secure against overfilling |
| Overfilling with gutta percha is statistically not related to poorer prognosis according to epidemiological studies |
| True | False |
| Apical abscess is a result of imbalance between root canal microorganisms and host's defense |
| Systemic antibiotics should be routinely used with abscesses |
| Fluctuating abscesses should be incised when no sinus tract is present |
| No drainage establishment is required after abscess incision |
| Chemomechanical preparation should be optimally finished at the first appointment in cases with an abscess |
| Instrumentation techniques can effect the risk of abscess formation (flare-up) |
| True | False |
| Spreading endodontic infections are common in endodontics |
| Spreading endodontic infections occur only after beginning of the treatment |
| Spreading endodontic infections are caused by aerobic bacteria |
| Spreading endodontic infections are often caused by Fusobacteria and (pepto)streptococci |
| Spreading endodontic infections are more difficult to detect than local abscesses |
| Spreading endodontic infections may require treatment in hospital |
| Spreading endodontic infections may require antibiotics in high doses, sometimes i.v. |
| True | False |
| The cause of persistent infection may be residual microbes in the root canal system |
| The cause of persistent infection may be surviving microbes in the periapical area |
| In periapical actinomycosis the microbes are primarily surviving in the root canal |
| Persisting infections are always symptomatic |
| Completing chemomechanical preparation at the first appointment is important for preventing persistent infections |
| Periapical surgery is always the first choice in persistent infections |
| True | False |
| Coronal leakage is a typical microbiological complication in endodontics |
| Inability to use rubber dam is a common cause for microbiological complications |
| Rubber dam is not important for successful endodontic treatment |
| Apical preparation is not important for infection control |
| Canal should be completely filled with calcium hydroxide for best effect |
| From an antibacterial point of view it is enough to have calcium hydroxide in the pulp chamber and coronal canal |
| Cotton pellet under temporary filling increases risk for leakage |
| Part of the pulp chamber in multirooted teeth can be filled with gutta percha and sealer |
| Aseptic complications always lead to periapical surgery to save the tooth |
| True | False |
| Tooth discoloration after endodontic treatment is typically caused by residual pulp tissue in pulp horns |
| Paraformaldehyde containing sealers may cause tooth discoloration |
| Silver containing sealers may cause tooth discoloration |
| 30% hydrogen peroxide is an etiologic factor in cervical resorption |
| Necrotic tooth without endodontic treatment cannot become discolored |
| "Walking bleaching" is often effective treatment for discolored endodontically treated teeth |