Cone-Beam Computed Tomography Assessment of Quality of Endodontic Treatment and Prevalence of Procedural Errors in Mandibular Molars

The association of endodontic prognostic factors with the presence of periapical lesion, its volume, and bone characteristics in endodontically treated molars: a cross-sectional study

BACKGROUND

This study intended to evaluate the association between several endodontic prognostic factors with the presence of periapical lesions (PLs), their volume, and bone characteristics including cortical bone destruction (CBD) and buccal plate bone height (BPBH) in root-filled molar teeth using cone-beam computed tomography.

METHODS

A collection of 143 scans of endodontically treated maxillary/mandibular first or second molars recorded over 8 years, were obtained from a specialized radiology center. Data on prognostic factors including tooth number, gender, jaw type, the status and number of missed canals, obturation length, restoration type, presence of a separated instrument, presence of a post or screw in the canals, and presence of perforation were collected. The assessed outcomes included PL presence, PL volume, CBD, and BPBH. The association between prognostic factors and outcomes was evaluated using multiple logistic regression models with adjusted covariates and multifactorial ANOVA at a significance level of 0.05.

RESULTS

A total of 282 molars from 82 women and 50 men with a mean age of 40.6 ± 12.27 were included. Among those, 139 teeth presented PL with a mean volume of 18.68 mm3. CBD was prevalent in 137 teeth and the mean BPBH appeared to be 9.45 mm. The presence of a missed canal (OR = 10.022, P < .05), underfilled canal (OR = 3.725, P < .05), overfilled canal (OR = 15.859, P = .018), and perforation (OR = 15.261, P = .013) was significantly associated with PLs. None of the prognostic factors could considerably contribute to the CBD (P > .05). The presence of a missed canal was positively associated with the PL volume (P < .05). Similarly, missed canals (P < .05), perforation (P < .05), and separated instruments (P = .004) were associated with a significantly reduced BPBH.

CONCLUSIONS

Overfillings, perforations, missed canals, and underfillings were identified as remarkable predictors of PL, arranged in descending order of their respective impact. The only factor capable of significantly increasing the PL volume was the missed canal. In brief, obturation length errors, perforations, missed canals, and separated instruments were robustly correlated with endodontic failure, which highlights the importance of mitigating the potential for errors by following the fundamentals of endodontics.

Cone-Beam Computed Tomography Assessment of Prevalence of Procedural Errors in Maxillary Posterior Teeth

A range of procedural errors can occur when performing endodontic treatment on posterior teeth. These errors may decrease the success rate in endodontic practice. This study assessed the prevalence of procedural errors and the quality of endodontic treatments in maxillary molars and premolars using cone-beam computed tomography (CBCT). CBCT scans from two private radiology centers were assessed retrospectively to ensure the same calculated sample size of 327 teeth for each of the four maxillary posterior tooth types (a total of 1,308 endodontically treated teeth). Image sets were evaluated for procedural errors categorized as follows: obturation length (overfilling or underfilling by >2 mm short of the root apex), missed canals, perforations, strip perforations (with extrusion of material into the furcation area), separated instruments in the root canal space, and root fracture. Data were analyzed with SPSS version 20 (SPSS Inc., Chicago, IL, USA), and frequency data was assessed using the Monte Carlo test at the 0.05 level of significance. The procedural errors most commonly reported in the present study were from most frequent to least frequent: underfilled canals (50.0%), missed canals (27.5%), overfilled canals (12.5%), apical perforations (5.0%), separated instruments (3.1%), and root fractures (1.9%). No strip perforations (with extrusion of material into the furcation area) were seen in the study (0%). Underfilled and missed root canals were the most frequent procedural errors identified in the present study. These findings underline the importance of more consideration of critical working length management during all stages of root canal treatment, greater awareness of root canal anatomy, and the use of imaging and diagnostic devices that enhance the ability to identify and treat root canals both safely and effectively.

Prevalence and Morphology of C-Shaped Canals in Mandibular First and Second Molars of an Iranian Population: A Cone-Beam Computed Tomography Assessment

Objectives

The complex anatomy of C-shaped canals poses challenges for clinicians compared to teeth with normal root canal anatomy. This study is aimed at evaluating the frequency and morphology of C-shaped canals in the mandibular first and second molars among an Iranian population using cone-beam computed tomography (CBCT).

Materials and Methods

This cross-sectional study evaluated 369 CBCT scans from the archives of a radiology clinic in Ardabil, Iran. The sample included 248 mandibular first molars and 478 mandibular second molars. The presence of C-shaped canals and their classification, according to Fan et al., were evaluated at four levels: orifice, coronal, middle, and apical. Prevalence based on gender and tooth type was also assessed.

Results

A total of 199 (53.9%) males and 170 (46.1%) females were evaluated. C-shaped canals were found in 11 (8 males/3 females) out of 248 (4.4%) first molars and in 20 (11 males/9 females) out of 478 (3.7%) second molars. The C2 configuration was most prevalent in the orifice, coronal, and middle levels of both molar types, while C3 and C4 morphologies were most commonly found apically in the second and first molars, respectively. A significant difference in configuration was found only at the coronal level between molar types. A significant association between gender and configuration was observed only at the orifice level of the second molars. No other significant differences were found (P > 0.05).

Conclusion

C-shaped canal configurations should be expected in 4.4% of mandibular first molars and 3.7% of the second molars in this Iranian population, with a predominance of the C2 configuration in the orifice, coronal, and middle levels.