This article describes a novel three‐dimensional classification for external cervical resorption (ECR). The European Society of Endodontology and American Association of Endodontists & American ...Academy of Oral & Maxillofacial Radiology position statements advise that Cone beam computed tomography should be considered for the assessment and/or management of root resorption if it appears to be clinically amenable to treatment following clinical and conventional radiographic examination. The new classification takes into account the ECR lesion height (1: at CEJ level or coronal to the bone crest (supracrestal), 2: extends into the coronal third of the root and apical to the bone crest (subcrestal), 3: extends into the mid‐third of the root, 4: extends into the apical third of the root), circumferential spread (A: ≤90° B: ≤180° C: ≤270° D: >270°) and proximity to the root canal (d: lesion confined to dentine, p: probable pulpal involvement), thus classifying ECR in three dimensions. At present, there is no classification to accurately describe ECR. This novel and clinically relevant three‐dimensional classification should allow effective and accurate communication of ECR lesions between colleagues. It will also allow the effect of the nature of ECR on the outcome of treatment to be assessed objectively.
Effective management of external cervical resorption (ECR) depends on accurate assessment of the true nature and accessibility of ECR; this has been discussed in part 1 of this 2 part article. This ...aim of this article was firstly, to review the literature in relation to the management of ECR and secondly, based on the available evidence, describe different strategies for the management of ECR. In cases where ECR is supracrestal, superficial and with limited circumferential spread, a surgical repair without root canal treatment is the preferred approach. With more extensive ECR lesions, vital pulp therapy or root canal treatment may also be indicated. Internal repair is indicated where there is limited resorptive damage to the external aspect of the tooth and/or where an external (surgical) approach is not possible due to the inaccessible nature of subcrestal ECR. In these cases, root canal treatment will also need to be carried out. Intentional reimplantation is indicated in cases where a surgical or internal approach is not practical. An atraumatic extraction technique and short extraoral period followed by 2‐week splinting are important prognostic factors. Periodic reviews may be indicated in cases where active management is not pragmatic. Finally, extraction of the affected tooth may be the only option in untreatable cases where there are aesthetic, functional and/or symptomatic issues.
Patel S, Wilson R, Dawood A, Foschi F, Mannocci F. The detection of periapical pathosis using digital periapical radiography and cone beam computed tomography – Part 2: a 1‐year post‐treatment ...follow‐up. International Endodontic Journal, 45, 711–723, 2012.
Aim Part 2 of this clinical study aims to compare the radiographic change in periapical status of individual roots determined using digital periapical radiographs versus cone beam computed tomography (CBCT) 1 year after primary root canal treatment and to determine the radiological outcome of treatment for each tooth.
Methodology Periapical radiographs and CBCT scans of 123 teeth in 99 patients assessed 1 year after completion of primary root canal treatment by a single operator were compared with their respective pre‐treatment (diagnostic) periapical radiographs and CBCT scans. The presence or absence as well as the increase or decrease in size of existing periapical radiolucency was assessed by a consensus panel consisting of two calibrated examiners. The panel viewed the images under standardized conditions. Paired comparison of the outcome diagnosis of individual roots and teeth was performed using generalized McNemar’s or Stuart–Maxwell test of symmetry analysis.
Results The ‘healed’ rate (absence of periapical radiolucency) for all roots combined was 92.7% using periapical radiographs and 73.9% for CBCT (P < 0.001). This rate increased to 97.2% and 89.4%, respectively, when the ‘healing’ group (reduced size of periapical radiolucency) was included (P < 0.001). A statistically significant difference in outcome diagnosis of single roots was observed between DPA and CBCT in single‐rooted teeth and the buccal or mesio‐buccal roots of multi‐rooted teeth (P < 0.05). Analysis by tooth revealed that the ‘healed’ rate (absence of periapical radiolucency) was 87% using periapical radiographs and 62.5% using CBCT (P < 0.001). This increased to 95.1% and 84.7%, respectively, when the ‘healing’ group (reduced size of periapical radiolucency) was included (P < 0.002). Outcome diagnosis of teeth showed a statistically significant difference between systems (P < 0.001). Reconstructed CBCT images revealed more failures (17.6%) in teeth with no pre‐operative periapical radiolucencies compared with periapical radiographs (1.3%) (P = 0.031). In teeth with existing pre‐operative periapical radiolucencies, reconstructed CBCT images also showed more failures (13.9%) compared with periapical radiographs (10.4%).
Conclusion Diagnosis using CBCT revealed a lower healed and healing rate for primary root canal treatment than periapical radiographs, particularly in roots of molars. There was a 14 times increase in failure rate when teeth with no pre‐operative periapical radiolucencies were assessed with CBCT compared with periapical radiographs at 1 year.
Aim
Part 2 of this prospective clinical study aimed to compare the 1‐year outcome of root canal retreatments, when individual roots and teeth were assessed by periapical radiographs and cone beam ...computed tomography (CBCT).
Methodology
Subjects participating in this study had been referred for management of an endodontic problem associated with one or more root filled teeth. Root canal retreatment was performed by Specialists or postgraduate students under the direct supervision of Specialist endodontic staff. A total of 98 teeth (84 patients) were reassessed clinically and radiographically 1 year after completion of root canal retreatment. The postoperative periapical radiographs and CBCT scans were compared with their respective pre‐treatment (diagnostic) periapical radiographs and CBCT scans. The increase or decrease in size of existing periapical radiolucencies and development of new radiolucencies were assessed by a consensus panel consisting of two calibrated examiners. They also determined an appropriate management plan for each case based on the radiographical findings. Comparison of the outcome diagnosis of individual roots and teeth and case management, when assessed by periapical radiographs and CBCT scans, was performed using chi‐squared and McNemar's tests.
Results
An overall favourable result of 93% success for teeth (96% roots) was recorded when the assessment was undertaken by periapicals compared with 77% success for teeth (87% roots) when assessed by CBCT. A significant difference in outcome diagnosis of single paired roots (P < 0.0001) and teeth (P = 0.0001) was observed when comparing periapicals to CBCT for the cohort of teeth as a whole. When comparing the future management plan on the basis of radiographic information alone, there was a significant difference between periapicals and CBCT‐based management (P = 0.01).
Conclusion
Diagnosis using CBCT revealed a significantly lower number of favourable outcomes than periapicals in root canal retreatment. This significantly affected the future management of cases attending for a review.
A single-blind randomized controlled clinical trial in patients with deep caries and symptoms of reversible pulpitis compared outcomes from a self-limiting excavation protocol using chemomechanical ...Carisolv gel/operating microscope (self-limiting) versus selective removal to leathery dentin using rotary burs (control). This was followed by pulp protection with mineral trioxide aggregate (MTA) and restoration with glass ionomer cement and resin composite, all in a single visit. The pulp sensibility and periapical health of teeth were assessed after 12 mo, in addition to the differences in bacterial tissue concentration postexcavation. Apical radiolucencies were assessed using cone beam computed tomography/periapical radiographs (CBCT/PAs) taken at baseline 0 mo (M0) and 12 mo (M12). In total, 101 restorations in 86 patients were placed and paired subsurface, and deep (postexcavation) dentin samples were obtained. DNA was extracted and bacteria-specific 16S ribosomal RNA gene quantitative polymerase chain reaction was performed. No significant difference was found in bacterial copy numbers normalized to mass of dentin (“bacterial tissue concentration”) between the self-limiting (96.3% reduction) and control protocols (97.1%, P = 0.33). The probability of 12-mo success was 4 times (odds ratio OR = 4.33; confidence interval CI, 1.2–15.6; P = 0.025) higher in the self-limiting protocol compared to the control (conventional excavation technique), with pulp survival rates of 73.3% and 90%, respectively (P = 0.049). Molars had a 4 times higher probability of success compared to premolars (OR, 4.17; CI, 1.17–14.9; P = 0.028), and symptom severity did not statistically predict outcome (OR, 0.41; CI, 0.12–13.9, P = 0.153). CBCT detected significantly more periapical (PA) lesions than PA radiographs at the baseline visit (P < 0.001). In conclusion, the self-limiting caries excavation protocol under magnification increased pulp survival rate compared to rotary bur excavation (ClinicalTrials.gov NCT03071588).
Stern S, Patel S, Foschi F, Sherriff M, Mannocci F. Changes in centring and shaping ability using three nickel–titanium instrumentation techniques analysed by micro‐computed tomography (μCT). ...International Endodontic Journal, 45, 514–523, 2012.
Aim To compare the centring ability and the shaping ability of ProTaper (PT) files used in reciprocating motion and PT and Twisted Files (TF) used in continuous rotary motion, and to compare the volume changes obtained with the different instrumentation techniques using micro‐computed tomography.
Methodology Sixty mesial canals of thirty mandibular molars were randomly assigned to three instrumentation techniques: group 1, canals prepared with the PT series (up to F2) (n = 20); group 2, canals prepared with the F2 PT in reciprocating motion (n = 20); group 3 canals prepared with the TF series (size 25) (n = 20). Teeth were scanned pre‐ and post‐operatively using micro‐computed tomography to measure volume and shaping changes, and the obtained results were statistically analysed using parametric tests.
Results The increase in canal volume obtained with the three instrumentation techniques was not significantly different. Canals were transported mostly towards the mesial aspect in the apical‐ and mid‐third of the roots, and towards the furcal aspect coronally. No difference in the transportation and centring ratio was found between the techniques. There was no significant difference between the times of instrumentation (TF: 62.5 ± 5.4 s; PT: 60.6 ± 3.9 s; and F2 PT file in reciprocating motion: 51.0 ± 3.3 s).
Conclusions ProTaper files used in reciprocating motion and PT and TF used in continuous rotary motion were capable of producing centred preparations with no substantial procedural errors.
Lennon S, Patel S, Foschi F, Wilson R, Davies J, Mannocci F. Diagnostic accuracy of limited‐volume cone‐beam computed tomography in the detection of periapical bone loss: 360° scans versus 180° ...scans. International Endodontic Journal, 44, 1118–1127, 2011.
Aim To investigate the effect of reducing limited‐volume cone‐beam computed tomographs arc of rotation from 360° to 180° on the ability to diagnose small, artificially created apical lesions.
Methodology Small, artificial apical bone lesions were prepared with a bur in the apical region of the distal root of ten mandibular first molars, in human dry mandibles. The jaws were scanned in a fixed position with limited‐volume CBCT making a 360° and 180° arc of rotation, before and after each periapical lesion had been created. A 4 × 4 cm field of view was used at 90 kV, with a current of 4 mA. Ten examiners blinded to the scan parameters and controls scored the presence/absence of bone lesions. Intra‐examiner reliability was determined after 2 weeks, reviewing half the data set. Statistical analyses with paired t‐tests determined the diagnostic accuracy of the two modalities (360° vs. 180°) in terms of sensitivity, specificity, receiver operating characteristic area under the curve, positive predictive values and negative predictive values.
Results The mean values for sensitivity of the 360° and 180° scans were 0.91 and 0.89, respectively; their mean specificities were 0.73. No significant differences were reflected in the statistical analyses.
Conclusions Both 360° and 180° cone‐beam computed tomography scans yielded similar accuracy in the detection of artificial bone lesions. The use of 180° scans might be advisable to reduce the radiation dose to the patient in line with the ICRP guidance to use as low a dosage as reasonably achievable.
Aim
To establish a nutrient‐stressed multispecies model biofilm and investigate the dynamics of biofilm killing and disruption by 1% trypsin and 1% proteinase K with or without ultrasonic activation.
...Methodology
Nutrient‐stressed biofilms (Propionibacterium acnes, Staphylococcus epidermidis, Actinomyces radicidentis, Streptococcus mitis and Enterococcus faecalis OMGS 3202) were grown on hydroxyapatite discs and in prepared root canals of single‐rooted teeth in modified fluid universal medium. The treatment groups included trypsin, proteinase K, 0.2% chlorhexidine gluconate and 1% sodium hypochlorite (NaOCl) (with and without ultrasonics). NaOCl and chlorhexidine were the positive controls and untreated group, and sterile saline was the negative control. The biofilms were investigated using confocal laser scanning microscopy (CLSM) with live/dead staining and quantitative microbial culture.
Results
Nutrient stress in the multispecies biofilm was apparent as the medium pH became alkaline, glucose was absent, and serum proteins were degraded in the supernatant. The CLSM showed the percentage reduction in viable bacteria at the biofilm surface level due to nutrient starvation. On the disc model, trypsin and proteinase K were effective in killing bacteria; their aerobic viable counts were significantly lower (P < 0.01) than the negative control and chlorhexidine. NaOCl was the most effective agent (P < 0.001). In the tooth model, when compared to saline, trypsin with ultrasonics caused significant killing both aerobically and anaerobically (P < 0.05). Chlorhexidine (1.46 ± 0.42), trypsin (3.56 ± 1.18) and proteinase K (4.2 ± 1.01) with ultrasonics were significantly effective (P < 0.05) in reducing the substratum coverage as compared to saline with ultrasonics (12% ± 4.9).
Conclusion
Trypsin with ultrasonic activation has a biofilm killing and disrupting potential.
A growing body of evidence suggests that non-viral hepatocellular carcinoma (HCC) might benefit less from immunotherapy.
We carried out a retrospective analysis of prospectively collected data from ...consecutive patients with non-viral advanced HCC, treated with atezolizumab plus bevacizumab, lenvatinib, or sorafenib, in 36 centers in 4 countries (Italy, Japan, Republic of Korea, and UK). The primary endpoint was overall survival (OS) with atezolizumab plus bevacizumab versus lenvatinib. Secondary endpoints were progression-free survival (PFS) with atezolizumab plus bevacizumab versus lenvatinib, and OS and PFS with atezolizumab plus bevacizumab versus sorafenib. For the primary and secondary endpoints, we carried out the analysis on the whole population first, and then we divided the cohort into two groups: non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) population and non-NAFLD/NASH population.
One hundred and ninety patients received atezolizumab plus bevacizumab, 569 patients received lenvatinib, and 210 patients received sorafenib. In the whole population, multivariate analysis showed that treatment with lenvatinib was associated with a longer OS hazard ratio (HR) 0.65; 95% confidence interval (CI) 0.44-0.95; P = 0.0268 and PFS (HR 0.67; 95% CI 0.51-0.86; P = 0.002) compared to atezolizumab plus bevacizumab. In the NAFLD/NASH population, multivariate analysis confirmed that lenvatinib treatment was associated with a longer OS (HR 0.46; 95% CI 0.26-0.84; P = 0.0110) and PFS (HR 0.55; 95% CI 0.38-0.82; P = 0.031) compared to atezolizumab plus bevacizumab. In the subgroup of non-NAFLD/NASH patients, no difference in OS or PFS was observed between patients treated with lenvatinib and those treated with atezolizumab plus bevacizumab. All these results were confirmed following propensity score matching analysis. By comparing patients receiving atezolizumab plus bevacizumab versus sorafenib, no statistically significant difference in survival was observed.
The present analysis conducted on a large number of advanced non-viral HCC patients showed for the first time that treatment with lenvatinib is associated with a significant survival benefit compared to atezolizumab plus bevacizumab, in particular in patients with NAFLD/NASH-related HCC.
•Recent evidences suggest that non-viral HCCs could be less responsive to immunotherapy.•Lenvatinib performs better compared to atezolizumab plus bevacizumab in non-viral HCC.•Sorafenib performs similarly to atezolizumab plus bevacizumab in non-viral HCC.
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