Does Calcium Hydroxide Reduce Endotoxins in Infected Root Canals? Systematic Review and Meta-analysis

Teaching pulpectomy in paediatric dentistry: A national cross-sectional survey of dental schools in Brazil

BACKGROUND

Pulpectomy is used to treat primary teeth with irreversibly inflamed or necrotic pulp tissue. There is, however, a lack of consensus on clinical protocols for teaching pulpectomy at dental schools.

AIM

To determine what faculty members at Brazilian dental schools are teaching about pulpectomy in primary teeth.

DESIGN

A cross-sectional, observational study was conducted using a 39-question survey available via the Google Forms® platform. A snowball sampling strategy was used for recruitment. Invitations to participate were sent via e-mail, WhatsApp® and Instagram®. The data were analysed descriptively.

RESULTS

A total of 177 (58.4%) responses were obtained. Most faculty members recommended the use of Kerr hand files (66.1%), and 1% sodium hypochlorite was the most common choice for the irrigating solution (35.3%). Iodoform pastes were the first choice of faculty members (41.6%), and 60.5% of the faculty members recommended composite resin as the definitive restoration.

CONCLUSION

Similarities were found in the teaching of pulpectomy for primary teeth among faculty members at dental schools in Brazil.

Efficacy of various techniques in calcium silicate-based intracanal medicament removal: a micro-CT analysis

The purpose of this study was to evaluate the efficacy of different techniques in removing calcium silicate intracanal medicament (Bio-C Temp). Forty human single-canaled premolars were randomly distributed into five groups (n = 8). All root canals were instrumented, then filled with Bio-C Temp. Following 1-week incubation, the intra-canal medicament was removed using one of five techniques according to tooth group: conventional syringe irrigation, Endo Activator, passive ultrasonic irrigation (PUI), ProTaper Universal F3 and XP-endo Finisher (XPF). Micro-CT scanning was performed before and after removal of Bio-C Temp. All techniques significantly reduced the volume of Bio-C Temp (p < 0.001) without reaching complete elimination. The percentage of Bio-C Temp removed was significantly higher in the XPF group (98.2%) compared to conventional syringe irrigation (70.6%), the Endo Activator (75.7%), and the ProTaper Universal (76.6%). There was no significant difference between the XPF and PUI (95.1%) groups. None of the removal techniques were able to completely remove Bio-C Temp from the root canal. However, XPF was the most effective method, but was not statistically significant when compared to PUI. Clinical Relevance: This study demonstrated that both XPF and PUI outperform conventional irrigation in removing Bio-C Temp intracanal medicament.

A clinical dilemma: Performing or avoiding root instrumentation in the treatment of the acute phase of endodontic-periodontal lesions? A case report

BACKGROUND

This study presents the diagnois, management, and tissue response to an acute periodontal lesion with deep pocketing affecting a maxillary central incisor in a young patient devoid of caries or a history of periodontitis.

METHODS

Clinical and radiographic examinations facilitated the diagnosis of the pathology as an endoperiodontal lesion (EPL) with root damage, exhibiting supracrestal invasive root resorption. Orthograde endodontic therapy was employed to decontaminate and seal the endodontic space. The resorptive site was treated through the endodontic access, debrided, and sealed. No periodontal therapy (surgical or nonsurgical) was performed. No mechanical instrumentation was performed within the pocketed root surface.

RESULTS

At 6-month and 1-year follow-ups after endodontic therapy the periodontium displayed a physiologically healthy condition without pus or inflammation, exhibiting a circumferential probing depth of 2 mm, and absence of tooth mobility. These favorable outcomes persisted throughout a 4-year follow-up period.

CONCLUSIONS

The spontaneous healing of pocketing and abscess occurred without mechanical root instrumentation following endodontic therapy and treatment of external invasive root resorption in an EPL.

KEY POINTS

Accurate diagnosis and identification of relevant etiologic factors are pivotal for effectively managing endodontic-periodontal lesions. Once a diagnosis is established, the therapy focuses on eliminating the primary cause, followed by a subsequent diagnostic phase after healing. The definitive understanding of the diagnosis and etiology of endodontic-periodontal lesions often becomes clear in retrospect, based on the outcomes of the therapy. When probing acute periodontal lesions, deep probing depths may occur without permanent loss of periodontal attachment. If the acute lesion was not induced by a periodontal cause and if no periodontal etiology arises secondarily, resolving the primary cause of the endoperiodontal lesion can lead to the spontaneous resolution of the pocketing. This results in spontaneous healing of periodontium without the need for intentional periodontal therapy. A clinical dilemma arises when considering periodontal treatment during the acute inflammatory phase of endo-periodontal pathology. It is advisable to refrain from mechanical root instrumentation particularly if a clear periodontal cause is not apparent, to prevent from iatrogenic damage to periodontal fibers and the potential risk of gingival recessions. However, this does not imply avoiding periodontal therapy entirely for every case. Rather, it is recommended to delay the decision on root instrumentation until a new diagnostic phase is conducted following the healing of the endodontic etiology.

Does single-visit root canal treatment of permanent teeth provide more benefit than a multiple-visit approach?

DATA SOURCES

Cochrane Oral Health's Trials Register, Cochrane Central Register of Controlled Trials in the Cochrane Library, MEDLINE Ovid, Embase Ovid.

STUDY SELECTION

Randomised controlled trials and quasi-randomised controlled trials were included.

POPULATION

Participants aged ≥ 10 with a permanent tooth possessing a completely formed apex and without resorption; Intervention: Root canal treatment (RoCT) carried out in a single visit; Comparison: RoCT carried out over multiple visits; Outcome: Primary outcome was treatment success (retention of tooth or radiographic evidence of healing), with secondary outcomes investigating post-operative symptoms (pain, swelling, sinus tract formation).

DATA EXTRACTION AND SYNTHESIS

Standard Cochrane methods to assess internal validity were used. The Robins 1 tool (for quasi randomised controlled trials) or risk of bias (RoB) 1 tool (for randomised controlled trials) were used to assess RoB whereby a judgement was assigned as 'low', 'high' or 'unclear'. GRADE (GRADEpro GDT software) was used to assess certainty of evidence for each outcome. The certainty of evidence was defined as high, moderate, low or very low, having no downgrade, downgrade of one level, downgrade of two levels and downgrade of three or more levels, respectively. Of the various subgroups investigated to determine their relevance, only pretreatment conditions (vital teeth versus necrotic teeth) and endodontic technique (manual versus mechanical instrumentation) were available for subgroup analysis. The Cochrane's test for heterogeneity and I2 test were used to assess the variation in treatment effects. A random-effects model was used to combine risk ratio (RR) for dichotomous data and mean difference (MD) for continuous data. Sensitivity analysis was performed for each outcome, excluding studies at overall high or unclear RoB.

RESULTS

Forty-seven studies were included in the meta-analysis and internal validity assessment, with 5693 teeth analysed. Ten studies were found to have a low RoB, 17 with a high RoB and 20 with an unclear RoB. No evidence was identified suggesting a difference between treatment carried out in a single visit compared to a multiple visits approach for the primary outcome measure, but there was very low certainty about the findings (RR 0.46, 95% confidence interval (CI) 0.09 to 2.50; I 2 = 0%; 2 studies, 402 teeth). No evidence was identified suggesting a difference between treatment carried out in a single visit compared to multiple visits with regards to radiological failure (RR 0.93, 95% CI: 0.81 to 1.07; I 2 = 0%; 13 studies, 1505 teeth; moderate-certainty evidence), participants reporting pain up to 72 h post obturation (RR 0.97, 95% CI: 0.81 to 1.16; I 2 = 70%; 12 studies, 1329 teeth; low-certainty evidence), pain for 72 h post obturation (MD 0.26, 95% CI: -4.76 to 5.29; I 2 = 98%; 12 studies, 1258 teeth; low-certainty evidence) or pain at 1 week post obturation (RR 1.05, 95% CI: 0.67 to 1.67; I2 = 61%; 9 studies, 1139 teeth; very low-certainty evidence). Similarly, no evidence was identified to prove that there was a difference between treatment carried out in a single visit compared to multiple visits with regards to swelling or flare-up (RR 0.56 95% CI: 0.16-1.92; I 2 = 0%; 6 studies; 605 teeth; very low-certainty evidence), analgesic use (RR 1.25 95% CI: 0.75-2.09; I 2 = 36%; 6 studies, 540 teeth; very low-certainty evidence) and sinus tract or fistula presence (RR 1.00, 95% CI: 0.24-4.28; I 2 = 0%; 5 studies, 650 teeth; very low-certainty evidence). Interestingly, however, there was evidence to show that more participants reported pain after 1 week following RoCT completed in a single visit, compared to those in multiple visit groups (RR 1.55, 95% CI: 1.14-2.09; I 2 = 18%; 5 studies, 638 teeth; moderate-certainty evidence). Subgroup analysis showed there was an increase in post-treatment pain after 1 week for RoCT carried out in a single visit on vital teeth (RR 2.16, 95% CI: 1.39-3.36; I 2 = 0%; 2 studies, 316 teeth), and with the use of mechanical instrumentation (RR 1.80, 95% CI: 1.10-2.92; I 2 = 56%; 2 studies, 278 teeth).

CONCLUSIONS

The current evidence shows that RoCT carried out in a single visit is no more effective than RoCT carried out over multiple visits; after 12 months, there is no difference in pain or complications with either approach. However, single visit RoCT has been shown to have increased post-operative pain after 1 week compared to RoCT completed over multiple visits.

In vitro inflammatory modulation of bioceramic endodontic sealer in macrophages stimulated by bacterial lipopolysaccharide

AIM

To evaluate the effects of AH Plus (Dentsply), Sealer 26 (Dentsply), and Sealer Plus BC (Produtos Médicos e Odontológicos) on cytotoxicity and inflammation in macrophage cultures exposed to bacterial lipopolysaccharide (LPS).

METHODOLOGY

After initial setting, the sealers were conditioned with serum-free culture medium for 24 h (1 ml/cm² ). Macrophages from the RAW 264.7 strain were exposed to sealer extracts in a 1:16 ratio in a culture medium with or without LPS. Cell morphology, viability, mitochondrial activity, oxidative stress and gene expression of interleukin 1β (IL-1β) and tumour necrosis factor-alpha (TNF-α) were evaluated. Data on mitochondrial activity, oxidative stress and TNF-α were analysed using a two-way analysis of variance (anova) test, followed by the Student-Newman-Keuls post-test. IL-1β data were analysed using one-way anova, followed by SNK, and the t-test was used for intragroup comparison. The significance level was set at 5%.

RESULTS

In the absence of LPS, only AH Plus and Sealer 26 showed a reduction in cell density, while in the presence of LPS, Sealer 26 had the lowest density compared to the other groups. In terms of mitochondrial activity, at 24 and 48 h, Sealer Plus BC had significantly higher mean values than Sealer 26 and AH Plus (p < .05). Sealer 26 exhibited the lowest levels of oxidative stress and IL-1β and TNF-α expression, regardless of the presence of LPS (p < .05).

CONCLUSIONS

Although all sealers interfere with the response of macrophages to LPS, contact with epoxy resin-based sealers can impair cell activity in vitro, while bioceramic sealer seems to favour the inflammatory functions of these cells.

An overview of systematic reviews on endotoxins in endodontic infections and the effectiveness of root canal therapy in its removal

Background The objective of this overview was to synthesise the current evidence on the role of endotoxins in endodontics infections and to evaluate the effectiveness of endodontic procedures in its removal using information from published systematic reviews.Methods Electronic databases Medline, Scopus, Embase, Cochrane Library and Google Scholar were searched for reviews published up to July 2021. Systematic reviews on endotoxins based on clinical and/or observational studies were included. The quality of systematic reviews was assessed with the AMSTAR2 tool.Results A total of five systematic reviews were selected, of which two reviews were of high quality. A significantly higher level of endotoxins were found in teeth with exudation, teeth with a previous episode of pain and pain on percussion. Chemomechanical preparation of root canals significantly reduce endotoxin levels. Calcium hydroxide intracanal medication in symptomatic teeth was significantly effective in endotoxin reduction (standardised mean difference -1.051 [95% confidence interval -2.039 to -0.063]; p <0.05; I2 = 83.3%; certainty of evidence = very low). Multiple session root canal treatment in teeth with symptomatic apical periodontitis was significantly more effective in endotoxins/lipopolysaccharides removal than single-session treatment.Conclusion Limited quality of evidence showed a significant association of endotoxins in infected teeth with clinical symptoms. Conventional chemomechanical preparation of root canals and intracanal medication were unable to eliminate endotoxins from the root canal system. Future evolution of effective disinfection therapies is warranted.