Knowledge of undergraduate and postgraduate dental students about managing traumatic dental injuries based on the 2020 International Association of Dental Traumatology guidelines: A online survey of 10 dental schools from 10 countries

BACKGROUND/AIM

The knowledge of dental students about managing traumatic dental injuries (TDIs) may not be uniform, depending on global location and dental education. The aim of this study was to evaluate the level of knowledge of undergraduate and postgraduate students specializing in endodontics and pediatric dentistry at 10 dental schools in 10 countries about the 2020 International Association of Dental Traumatology (IADT) guidelines regarding the management of TDIs.

MATERIALS & METHODS

A previously published questionnaire was used in the current survey. It was an online survey with 12 questions regarding the management of TDIs and some additional questions regarding sociodemographic and professional profiles of the participants were added. The survey was distributed to final-year undergraduate students and postgraduate students in pediatric dentistry and endodontics from 10 dental schools. Simple frequency distributions and descriptive statistics were predominantly used to describe the data. Differences in the median percentage scores among the student categories were assessed using the Kruskal-Wallis test followed by Dwass-Steel-Critchlow-Fligner pairwise comparisons.

RESULTS

A total of 347 undergraduates, 126 postgraduates in endodontics, and 72 postgraduates in pediatric dentistry from 10 dental schools participated in this survey. The postgraduates had a significantly higher percentage score for correct responses compared with the undergraduates. No significant difference was observed between the endodontic and pediatric dentistry postgraduates.

CONCLUSION

The knowledge possessed by undergraduate and postgraduate students concerning the IADT-recommended management of TDIs varied across the globe and some aspects were found to be deficient. This study emphasizes the critical importance of reassessing the teaching and learning activities pertaining to the management of TDIs.

Effectiveness of root resection techniques compared with root canal retreatment or apical surgery for the treatment of apical periodontitis and tooth survival: A systematic review

BACKGROUND

To manage apical periodontitis in root filled maxillary and mandibular molars, root resection techniques may be employed to avoid the loss of the tooth.

OBJECTIVES

The objectives of the study were to systematically analyse the effectiveness of root resection techniques (root resection/crown resection/root amputation) for the management of apical periodontitis with non-surgical root canal retreatment or apical surgery by the evaluation of clinical and patient-related outcomes (PROMS), in human experimental studies and longitudinal studies.

METHODS

An electronic literature search in PubMed, MEDLINE via OVID interface, EMBASE and Cochrane Central, supplemented by a manual hand search of the grey literature, was performed up to 25th September 2021. Randomized controlled trials, comparative clinical trials and observational studies reporting on the outcome (tooth survival and patient-reported outcome measures with a minimum follow-up of 1 year) of root resection techniques for treating apical periodontitis were identified. The risk of bias was evaluated using the Newcastle-Ottawa scale.

RESULTS

From a total of 2098 reports, 36 were considered for further screening. Three retrospective studies, published between 2018 and 2020, were included in this systematic review. A high heterogeneity in terms of protocols, study design and the reported outcomes were observed. The risk of bias was scored as low to moderate. These three studies consisted of data from 305 resected teeth, from 254 patients, with a follow-up period of 1-16.8 years. Overall, 151 teeth were extracted during the follow-up period. In these studies, root resection treatment was carried out on 42 teeth exclusively for endodontic reasons. One of these studies reported 12 out of 23 teeth lost at follow-up. None of the studies reported on PROMS.

DISCUSSION

Although root resection techniques may be used for treating teeth with apical periodontitis, the data are limited. Furthermore, the studies are very heterogeneous and associated with high risk of bias.

CONCLUSIONS

Given the current level of available evidence, it is not possible to recommend, or dismiss, root resection techniques for managing apical periodontitis.

REGISTRATION

PROSPERO database (CRD42021260306).

Effect of Guided Tissue Regeneration on the Success of Surgical Endodontic Treatment of Teeth with Endodontic-Periodontal Lesions: a Systematic Review

BACKGROUND

Endodontic-periodontal lesions may need surgical approach and the application of guided tissue regeneration (GTR) to be treated by a combined approach.

OBJECTIVES

The aim of the present study was to evaluate the effects of GTR on the success (clinical and radiological healing) of teeth with endodontic-periodontal lesions treated by modern surgical endodontic treatment, by means of a systematic review of the literature.

METHODS

An exhaustive electronic (Medline, Embase and Scopus searched from inception to August 2020) and manual literature search combined with strict inclusion and exclusion criteria was undertaken to identify any clinical (prospective case series or comparative trials) studies that assessed the added benefit of GTR in modern surgical endodontic treatment of teeth with endodontic-periodontal lesions. The success of the treatment was assessed based on radiographic healing and clinical evaluations. The risk of bias of the identified studies was evaluated using the Cochrane's collaboration RoB 2.0 tool and the Joanna Briggs Institute (JBI) critical appraisal tools.

RESULTS

A systematic literature search for eligible reports retrieved three randomized controlled trials (RCTs) and one prospective single arm study with a total of 125 teeth in 125 subjects. One of the RCTs has a low risk of bias, while the other two raised some concerns, using the RoB 2.0 tool. Due to the heterogeneity of the results, it was not possible to perform a comparative meta-analysis and the results are presented in a narrative manner and by calculating pooled outcomes. Pooling together the data from all the included studies, the reported outcome was of complete healing in 58.4% of all cases, of scar tissue formation / incomplete healing in 24% of cases, of uncertain healing in 12.8% of cases, and of failure in 4.8% of all analyzed teeth, with a follow-up ranging from 12 to 60 months.

CONCLUSIONS

The scientific evidence about the use of GTR in modern surgical endodontic treatment of endodontic-periodontal lesion is sparse, and the available results are derived from very heterogeneous studies, thus not permitting to clarify which is the most effective treatment option in these cases, also due to the absence of studies comparing GTR versus no GTR.

The Effect of General Anesthesia on the Outcome of Root Canal Treatment in Pediatric Patients—A Retrospective Cohort Study

This study aimed to evaluate the effect of general anesthesia (GA) on the 1-year outcome of Root Canal Treatment (RCT) performed in pediatric patients and to compare it to the outcome of RCT in pediatric patients without GA. Patients admitted for RCT in permanent dentition in a public hospital, dated 2015 to 2020, age 8–15 with a minimum of one year follow-up period, were included in the study. The sample consisted of 326 teeth from 269 patients treated by a single operator, with a recall rate of 81%. Overall, 124 teeth were treated under GA and 142 teeth were without GA. The mean follow-up time was 31.5 months. Data underwent statistical analysis and the significance threshold was set for p < 0.05. Of the total cases, 90% showed favorable outcomes. A significantly higher favorable outcome was seen in the GA group than in the non-GA group (98% and 85%, respectively, p < 0.001). The outcome was significantly affected by the type and quality of the coronal restoration, degree of root development, and lesion size (p < 0.05). According to the current study, in uncooperative pediatric patients, a more favorable outcome of root canal treatment can be obtained under GA than LA if the procedure is carried out with immediate restoration.

The effect of imaging modality on the evaluation of the outcome of endodontic surgery

OBJECTIVES

The aim of this study was to assess the effect of the imaging modality on the evaluation of the outcome of modern surgical endodontic treatments, based on a systematic review of the literature.

METHODS

Strict inclusion criteria were adopted in order to identify studies that assessed the outcome of surgical endodontic treatments. Treatment success rates were pooled. The effect of the imaging modality used for the outcome assessment, and the methodological quality of the studies (based on the risk of bias (ROB)), were evaluated.

RESULTS

Nineteen articles were included. The success rates assessed by periapical (PA) radiography were significantly higher than when cases were evaluated by cone beam computed tomography (CBCT; 90 and 35% respectively). This difference was mainly due to a significant proportion of cases that were assessed by CBCT as uncertain healing (48%) compared to only 4% using PA. The success rates ranged between 86 and 92% in low ROB studies, and between 19-100% in high ROB studies.

CONCLUSIONS

Outcome assessment based on CBCT may lead to significantly lower estimates of rate of success, and higher rates of uncertain healing, thus presenting a dilemma in the decision-making following surgical endodontic treatment. The success rates of studies with lower methodological quality are more variable than for high quality studies.

Targeting Persistent Biofilm Infections: Reconsidering the Topography of the Infection Site during Model Selection

The physiology of an organism in the environment reflects its interactions with the diverse physical, chemical, and biological properties of the surface. These principles come into consideration during model selection to study biofilm–host interactions. Biofilms are communities formed by beneficial and pathogenic bacteria, where cells are held together by a structured extracellular matrix. When biofilms are associated with a host, chemical gradients and their origins become highly relevant. Conventional biofilm laboratory models such as multiwall biofilm models and agar plate models poorly mimic these gradients. In contrast, ex vivo models possess the partial capacity to mimic the conditions of tissue-associated biofilm and a biofilm associated with a mineralized surface enriched in inorganic components, such as the human dentin. This review will highlight the progress achieved using these settings for two models of persistent infections: the infection of the lung tissue by Pseudomonas aeruginosa and the infection of the root canal by Enterococcus faecalis. For both models, we conclude that the limitations of the conventional in vitro systems necessitate a complimentary experimentation with clinically relevant ex vivo models during therapeutics development.

The Products of Probiotic Bacteria Effectively Treat Persistent Enterococcus faecalis Biofilms

Objectives: Enterococcus faecalis is a Gram-positive commensal bacterium that possesses various survival and virulence factors, including the ability to compete with other microorganisms, invade dentinal tubules, and resist nutritional deprivation. E. faecalis is associated with persistent endodontic infections where biofilms formed by this bacterium in the root canal frequently resist dental therapies. Aseptic techniques, such as the inclusion of sodium hypochlorite, are the most commonly used methods to treat E. faecalis infections within the root canal system. In this work, we assess the effectiveness of probiotic strains to prevent the regrowth of E. faecalis biofilm cells treated by sodium hypochlorite irrigation. Methods: First, methods are presented that evaluate the effects of short-term exposure to sodium-hypochlorite on established E. faecalis. Next, we evaluate the effects of the secreted products of probiotic strains on biofilm cells and planktonic cells. Results: Sodium hypochlorite, the treatment conventionally used to decontaminate infected root canal systems, was extremely toxic to planktonic bacteria but did not fully eradicate biofilm cells. Furthermore, low concentrations of sodium hypochlorite induced eDNA dependent biofilms. Strikingly, conditioned medium from the probiotic bacteria Lactobacillus plantarum and Lactobacillus casei was sufficient to fully prevent the regrowth of treated biofilms while showing reduced potency towards planktonic cells. Conclusion: Sodium hypochlorite irrigations may contribute to the persistence of biofilm cells if used at concentrations lower than 3%. Probiotic strains and their products represent a new reservoir of biofilm therapies for E. faecalis infections formed in the root canal system.

The Development of Large Radicular Cysts in Endodontically Versus Non-Endodontically Treated Maxillary Teeth

Background and Objectives: Large radicular cysts of the maxilla present a clinical challenge, as they may cause recurrent infection, severe alveolar bone loss and disruption of the nasal and maxillary sinus floors. The aim of this study was to evaluate the effect of previous root canal treatment on the clinical presentation of large maxillary radicular cysts. Materials and Methods: All cases of radicular cysts treated at the Oral and Maxillofacial Surgery Department of a tertiary public hospital over a period of six years (2012–2018) were evaluated. Histologically confirmed radicular cysts of the maxilla with a maximal dimension of over 15 mm were included. Demographic data of the patients, clinical presentation and radiographic features of the lesions were analyzed. Results: A total of 211 inflammatory cysts were treated in the study period, of these 54 histologically diagnosed radicular cysts in the maxilla were found to have a maximal dimension of over 15 mm. The mean age of patients with large maxillary radicular cysts was 43.3 years, 57.6% of which were male and 42.4% female. The lateral incisor was the most common tooth affected (46.3%). The mean size of the large radicular cysts was 25 mm. Then, 83.8% of the cysts were observed in teeth with previous endodontic treatment. Teeth without endodontic treatment presented clinically with significantly fewer acute symptoms in comparison to teeth with previous endodontic treatment. Conclusions: the vast majority (83.8%) of large maxillary radicular cysts were associated with endodontically treated teeth. Previous endodontic treatment was correlated to increased frequency of clinical symptoms.

Effect of cone beam computed tomography voxel size and dental specialty status on the agreement of observers in the detection and measurement of periapical lesions

OBJECTIVE

To compare observer agreement between endodontists and oral and maxillofacial radiologists (OMRs) in the detection and measurement of periapical lesions as depicted in cone beam computed tomography (CBCT) with 2 voxel sizes.

STUDY DESIGN

In total, 256 CBCT images of maxillary molars were evaluated by 2 endodontists and 2 OMRs. Images were obtained at voxel sizes of 0.2 and 0.4 mm. Observers evaluated 64 endodontically and 64 nonendodontically treated teeth for the presence of periapical lesions using a 5-point confidence scale. Weighted κ values were calculated to determine intra- and interobserver agreement. Intraclass correlation coefficients (ICCs) were calculated to assess intra- and interobserver agreement in width and height measurements of the lesions.

RESULTS

Intraobserver agreement ranged from fair to almost perfect, with κ values higher for the OMRs than for the endodontists. Interobserver agreement between endodontists ranged from fair to moderate at the 0.2mm voxel size and was slight at 0.4 mm. Agreement between OMRs was almost perfect at 0.2 mm and ranged from substantial to almost perfect at 0.4 mm. ICC was excellent for all observers in all conditions.

CONCLUSIONS

Intra- and interobserver reliability was affected by voxel size and specialty. Correlation for measurements exhibited no variation.

Accuracy for diagnosis of periapical cystic lesions

Clinical differentiation between cystic lesions of endodontic and non-endodontic origin is of importance because correct diagnosis may affect treatment decision making. Most radicular cysts are treated with conservative approaches and, therefore, are not surgically removed. The objective of this study was to determine the accuracy of clinical diagnosis of periapical lesions as compared to the histological findings, and to evaluate various associated factors. All biopsy specimens submitted for histological evaluation from 2002 to 2009 were assessed. Only cases of periapical lesions with complete patient data and clinical diagnosis were included. Sensitivity, specificity and accuracy of the clinical diagnosis were calculated and various patient-related factors were evaluated. Of the 4,908 cases, 183 met inclusion criteria. Histologically, there were 171 lesions of radicular cysts and 12 cases of non-endodontic cysts, including OKC and Incisive Canal Cyst. The diagnostic accuracy for clinical diagnosis for radicular cysts was 91.84% and 91.84% for non-endodontic cysts. There was a high accuracy of clinical differentiation between cystic lesions of endodontic and non-endodontic origin. However, some non-endodontic lesions may be incorrectly diagnosed clinically as lesions of endodontic origin. Histological evaluation may be necessary for the correct diagnosis. Further clinical studies are needed to evaluate clinical examination and histological diagnosis of periapical lesions.

Dental implant placement is a possible risk factor for the development of multiple cracks in non-endodontically treated teeth

The objective of this study was to evaluate potential risk factors, including the placement of dental implants, for the development of tooth cracks. A series of 212-patients, who were referred for endodontic treatment, were retrospectively screened, of which 72 (34%) patients had been diagnosed with 80-cracked teeth confirmed with an operating microscope. These patients had an average age of 53-years and were equally distributed between genders. Forty-one percent of the cracked teeth were diagnosed after the placement of dental implants, with an average of 3-implants per patient. Seventy percent of the cracks were diagnosed more than 1-year after implant loading. Implant placement was associated with higher odds of having multiple cracks (OR = 9.78, CI:2.320, 41.216)(p < 0.05). The proportion of cracked premolars was relatively high (30%), and most cracked teeth (79%) were vital and with a normal periapical diagnosis (86%). Most cracked teeth (71%) had an amalgam restoration, and teeth restored with amalgam were at a higher risk of having multiple cracks (p < 0.05). Clinicians should be aware of a common profile of endodontic patients with multiple cracks in a non-endodontically treated premolar, restored with an amalgam restoration, which was diagnosed with the cracks more than 1-year after reconstruction utilizing multiple implants.

Oral cancer-associated fibroblasts predict poor survival: Systematic review and meta-analysis

OBJECTIVES

To perform systematic review and meta-analysis on correlations between cancer-associated fibroblasts (CAFs) and the risk of death for patients with oral squamous cell carcinoma.

SUBJECTS AND METHODS

English literature (1966-2018) was systematically analyzed for studies that immunohistochemically assessed CAF density by alpha-smooth muscle actin and presented 5 year survival rates by Kaplan-Meier plots. Mean age of patients, proportion of male/female patients, and male/female majority (>50% male/female patients) per study were also collected. Significance level for statistical models was p < 0.05.

RESULTS

Meta-analysis comprised 11 studies/1,040 patients. Univariate Cox regressions showed that high CAF density was a negative prognostic factor in studies with female and male majority [OR 5.329 (95% CI 3.223-8.811), p < 0.001, and OR 2.208 (95% CI 1.717-2.839), p < 0.001, respectively]. High CAF density with male majority was associated with a more favorable prognosis [OR 0.996 (95% CI 0.979-1.013), p < 0.001]. Multivariate Cox regressions showed that death risk was significantly higher among patients with high CAF density compared to low CAF [OR 2.741 (95% CI 2.220-3.384) p < 0.001]. High mean age and male proportion were significantly protective [OR 0.940 (95% CI 0.925-9.955), p < 0.001, OR 0.125 (95% CI 0.018-0.867), p = 0.035), respectively].

CONCLUSIONS

CAFs increased death risk, male majority, and higher mean age were protective. A clinically validated cutoff for CAF density could serve as a reliable prognostic tool.

PRISMA for abstracts: best practice for reporting abstracts of systematic reviews in Endodontology

An abstract is a brief overview of a scientific, clinical or review manuscript as well as a stand-alone summary of a conference abstract. Scientists, clinician-scientists and clinicians rely on the summary information provided in the abstracts of systematic reviews to assist in subsequent clinical decision-making. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) for Abstracts checklist was developed to improve the quality, accuracy and completeness of abstracts associated with systematic reviews and meta-analyses. The PRISMA for Abstracts checklist provides a framework for authors to follow, which helps them provide in the abstract the key information from the systematic review that is required by stakeholders. The PRISMA for Abstracts checklist contains 12 items (title, objectives, eligibility criteria, information sources, risk of bias, included studies, synthesis of results, description of the effect, strength and limitations, interpretation, funding and systematic review registration) under six sections (title, background, methods, results, discussion, other). The current article highlights the relevance and importance of the items in the PRISMA for Abstracts checklist to the specialty of Endodontology, while offering explanations and specific examples to assist authors when writing abstracts for systematic reviews when reported in manuscripts or submitted to conferences. Strict adherence to the PRISMA for Abstracts checklist by authors, reviewers, and journal editors will result in the consistent publication of high-quality abstracts within Endodontology. This article is protected by copyright. All rights reserved.

Extended Maxillary Sinus Augmentation to the Apical Area of the Neighboring Teeth: Advantages and Limitations

The extension of sinus floor augmentation beyond the edentulous area, apical to the adjacent teeth, has many therapeutic advantages, but the reliability and safety of the procedure has not been assessed in depth. The present study compares the gain of bone anterior and posterior to the edentulous area and evaluates potential advantages and limitations in the clinical setting. The maximum vertical bone height in the edentulous and extended maxillary sinus augmentation (EMSA) areas and the thickness of the sinus membrane of 65 patients were measured. Those measurements were analyzed using the t test and Pearson correlations. The average vertical bone gain was 11.98 ± 3.53 mm in the edentulous sinus area and 8.60 ± 3.89 mm in the EMSA area (P < .05). Minor perforations of the sinus membrane occurred in 4 patients. There were no postsurgical graft contaminations or periradicular changes during follow-up. EMSA is a reliable and safe procedure with a very low complication rate. This approach is effective and safe for patients who have lost part of their posterior dentition. It enables future implant placement while avoiding the need for sinus reentry and proximal teeth extraction.

Inferior alveolar nerve block for the treatment of teeth presenting with irreversible pulpitis: A systematic review of the literature and meta-analysis

OBJECTIVE

The objective of the present systematic review was to evaluate, in patients with irreversible pulpitis affecting mandibular posterior teeth, if premedication with nonsteroidal anti-inflammatory drugs can increase the efficacy of inferior alveolar nerve block (IANB) if compared to placebo administration; if one anesthetic agent is more effective than another; if 1.8 mL injection is more effective than 3.6 mL injection to increase the efficacy of IANB; and if supplementary buccal injection is able to increase the efficacy of IANB as compared to a negative control/placebo group.

DATA SOURCES

Randomized controlled clinical trials investigating different aspects (technique, premedication with anti-inflammatory drugs, different anesthetic agents) were searched. Success of IANB, as defined in the studies, was considered as the primary outcome. A meta-analysis was performed evaluating relative risks (RRs). Electronic databases (Medline, Embase, Cochrane Central) were searched after preparation of an appropriate search string. After application of selection criteria, a total of 37 studies were included; 19 of them were considered in the meta-analysis. There was evidence of a difference in favor of the use of premedication with anti-inflammatory drugs (RR, 1.80; CI 95%, 1.50-2.14; P < .0001). There was no evidence of a difference between articaine and lidocaine (RR, 1.05; CI 95%, 0.91-1.21; P = .94). With regard to the volume of anesthetic infiltrated, the computed RR was 1.17 (CI, 0.73-1.88) without any significant difference between the use of one or two cartridges (P = .52). The estimated RR for a supplementary buccal infiltration was 1.56 (CI, 1.00-2.42; P = .05).

CONCLUSION

The use of premedication with anti-inflammatory drugs before IANB can increase the efficacy of the IANB. The type of anesthetic agent, the volume of anesthetic, and the use of a supplemental buccal infiltration do not seem to affect the efficacy of anesthesia.

Modern surgical endodontic treatment of altered sensation following extrusion of endodontic filling materials

AIM

This study presents the use of a modern surgical endodontic technique for the treatment of altered sensation following extrusion of endodontic filling materials.

CASE PRESENTATION

A patient presented with an altered sensation following a root canal treatment and extrusion of root filling material at the mandibular canine and lateral incisor. She was treated using a modern surgical technique that included removal of the extruded filling materials followed by root-end management and obturation. The treatment resulted in complete periapical and neurosensory healing.

CONCLUSIONS

Modern endodontic surgery may be beneficial for patients with nerve injury due to extruded endodontic filling materials, since it enables a relatively safe removal of the irritating extruded endodontic materials, proper root-end management and preservation of the natural tooth.

Eradication of Enterococcus faecalis Biofilms on Human Dentin

Objectives: This work assesses different methods to interfere with Enterococcus faecalis biofilms formed on human dentin slabs.

Methods: First, methods are presented that select for small molecule inhibitors of biofilm targets using multi-well polystyrene biofilm plates. Next, we establish methodologies to study and interfere with biofilm formation on a medically relevant model, whereby biofilms are grown on human root dentin slabs.

Results: Non-conventional D-amino acid (D-Leucine) can efficiently disperse biofilms formed on dentin slabs without disturbing planktonic growth. Cation chelators interfere with biofilm formation on dentin slabs and polystyrene surfaces, and modestly impact planktonic growth. Strikingly, sodium hypochlorite, the treatment conventionally used to decontaminate infected root canal systems, was extremely toxic to planktonic bacteria, but did not eradicate biofilm cells. Instead, it induced a viable but non-culturable state in biofilm cells when grown on dentin slabs.

Conclusion: Sodium hypochlorite may contribute to bacterial persistence. A combination of the methods described here can greatly contribute to the development of biofilm inhibitors and therapies to treat Enterococcus faecalis infections formed in the root canal system.

Metaplastic changes in the epithelium of radicular cysts: A series of 711 cases

Background

This study was aimed to evaluate the prevalence of metaplastic changes in the epithelium of radicular cysts and to investigate how they relate to the clinical and radiographic characteristics of the cysts, based on a large series of radicular cysts.

Material and Methods

Biopsies of cysts of endodontic origin that were examined at the Department of Oral Pathology between 2004 and 2011 have been re-evaluated for this study. Only cases that were re-confirmed with clinical and histological diagnoses of a radicular or residual radicular cyst were included. The included cases were evaluated for the prevalence of metaplastic changes in the form of mucous secreting cells (MSC) or ciliated cells (CC). The relations between the metaplastic changes and the cyst type (radicular or residual radicular), as well as demographic, clinical and radiographic parameters, were statistically evaluated using Fischer and chi-square tests. Significance was set at p<0.05.

Results

A total of 711 cysts were included: 677 were radicular cysts (95%) and 34 (5%) were residual radicular cysts. 23 cases had histopathological diagnoses other than radicular or residual radicular cysts and were excluded from the study. MSC were present in 47 (6.6%) cysts. MSC were significantly more common in residual radicular cysts than in radicular cysts [8 (23.5%) and 39 (5.8%), respectively; p<0.001]. MSC-containing cysts were commonly found in asymptomatic patients (10.5%, p<0.001), and usually presented with well-defined radiographic borders (7.2%, p<0.05). CC were present in 34 (4.8%) cysts, with a markedly high prevalence in the maxillary molar sextant (15%, p<0.001).

Conclusions

In the epithelium of radicular and residual radicular cysts the presence of specific metaplastic changes may be related to cyst type, symptomatology, radiographic findings and tooth location.

Key words:Radicular cyst, metaplasia, mucous secreting cells, ciliated cells.

Endodontic procedures for retreatment of periapical lesions

BACKGROUND

When primary root canal therapy fails, periapical lesions can be retreated with or without surgery. Root canal retreatment is a non-surgical procedure that involves removal of root canal filling materials from the tooth, followed by cleaning, shaping and obturating of the canals. Root-end resection is a surgical procedure that involves exposure of the periapical lesion through an osteotomy, surgical removal of the lesion, removal of part of the root-end tip, disinfection and, commonly, retrograde sealing or filling of the apical portion of the remaining root canal. This review updates one published in 2008.

OBJECTIVES

To assess effects of surgical and non-surgical therapy for retreatment of teeth with apical periodontitis.To assess effects of surgical root-end resection under various conditions, for example, when different materials, devices or techniques are used.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Trials Register (to 10 February 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 1), MEDLINE Ovid (1946 to 10 February 2016) and Embase Ovid (1980 to 10 February 2016). We searched the US National Registry of Clinical Trials (ClinicalTrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials (to 10 February 2016). We placed no restrictions regarding language and publication date. We handsearched the reference lists of the studies retrieved and key journals in the field of endodontics.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) involving people with periapical pathosis. Studies could compare surgery versus non-surgical treatment or could compare different types of surgery. Outcome measures were healing of the periapical lesion assessed after one-year follow-up or longer; postoperative pain and discomfort; and adverse effects such as tooth loss, mobility, soft tissue recession, abscess, infection, neurological damage or loss of root sealing material evaluated through radiographs.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from included studies and assessed their risk of bias. We contacted study authors to obtain missing information. We combined results of trials assessing comparable outcomes using the fixed-effect model, with risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, and 95% confidence intervals (CIs). We used generic inverse variance for split-mouth studies.

MAIN RESULTS

We included 20 RCTs. Two trials at high risk of bias assessed surgery versus a non-surgical approach: root-end resection with root-end filling versus root canal retreatment. The other 18 trials evaluated different surgical protocols: cone beam computed tomography (CBCT) versus periapical radiography for preoperative assessment (one study at high risk of bias); antibiotic prophylaxis versus placebo (one study at unclear risk); different magnification devices (loupes, surgical microscope, endoscope) (two studies at high risk); types of incision (papilla base incision, sulcular incision) (one study at high risk and one at unclear risk); ultrasonic devices versus handpiece burs (one study at high risk); types of root-end filling material (glass ionomer cement, amalgam, intermediate restorative material (IRM), mineral trioxide aggregate (MTA), gutta-percha (GP), super-ethoxy benzoic acid (EBA)) (five studies at high risk of bias, one at unclear risk and one at low risk); grafting versus no grafting (three studies at high risk and one at unclear risk); and low energy level laser therapy versus placebo (irradiation without laser activation) versus control (no use of the laser device) (one study at high risk).There was no clear evidence of superiority of the surgical or non-surgical approach for healing at one-year follow-up (RR 1.15, 95% CI 0.97 to 1.35; two RCTs, 126 participants) or at four- or 10-year follow-up (one RCT, 82 to 95 participants), although the evidence is very low quality. More participants in the surgically treated group reported pain in the first week after treatment (RR 3.34, 95% CI 2.05 to 5.43; one RCT, 87 participants; low quality evidence).In terms of surgical protocols, there was some inconclusive evidence that ultrasonic devices for root-end preparation may improve healing one year after retreatment, when compared with the traditional bur (RR 1.14, 95% CI 1.00 to 1.30; one RCT, 290 participants; low quality evidence).There was evidence of better healing when root-ends were filled with MTA than when they were treated by smoothing of orthograde GP root filling, after one-year follow-up (RR 1.60, 95% CI 1.14 to 2.24; one RCT, 46 participants; low quality evidence).There was no evidence that using CBCT rather than radiography for preoperative evaluation was advantageous for healing (RR 1.02, 95% CI 0.70 to 1.47; one RCT, 39 participants; very low quality evidence), nor that any magnification device affected healing more than any other (loupes versus endoscope at one year: RR 1.05, 95% CI 0.92 to 1.20; microscope versus endoscope at two years: RR 1.01, 95% CI 0.89 to 1.15; one RCT, 70 participants, low quality evidence).There was no evidence that antibiotic prophylaxis reduced incidence of postoperative infection (RR 0.49, 95% CI 0.09 to 2.64; one RCT, 250 participants; low quality evidence).There was some evidence that using a papilla base incision (PBI) may be beneficial for preservation of the interdental papilla compared with complete papilla mobilisation (one RCT (split-mouth), 12 participants/24 sites; very low quality evidence). There was no evidence of less pain in the PBI group at day 1 post surgery (one RCT, 38 participants; very low quality evidence).There was evidence that adjunctive use of a gel of plasma rich in growth factors reduced postoperative pain compared with no grafting (measured on visual analogue scale: one day postoperative MD -51.60 mm, 95% CI -63.43 to -39.77; one RCT, 36 participants; low quality evidence).There was no evidence that use of low energy level laser therapy (LLLT) prevented postoperative pain (very low quality evidence).

AUTHORS' CONCLUSIONS

Available evidence does not provide clinicians with reliable guidelines for treating periapical lesions. Further research is necessary to understand the effects of surgical versus non-surgical approaches, and to determine which surgical procedures provide the best results for periapical lesion healing and postoperative quality of life. Future studies should use standardised techniques and success criteria, precisely defined outcomes and the participant as the unit of analysis.

Microsurgical re-treatment of an endodontically treated tooth with an apically located incomplete vertical root fracture: a clinical case report

Although it is challenging, the early diagnosis of a vertical root fracture (VRF) is crucial in order to ensure tooth preservation. The purpose of this clinical case report was to describe reparative surgery performed to treat a tooth affected by an incomplete VRF. A 26 year old male patient was suspected to have a VRF in a maxillary left central incisor, and an exploratory flap was performed in order to confirm the diagnosis. After detecting the fracture, the lesion was surgically treated, the fracture and the infected root-end were removed, and a platelet-rich plasma membrane was used to cover the defect in order to prevent bacterial migration. A 24 month clinical and radiological follow-up examination showed that the tooth was asymptomatic and that the healing process was in progress. The surgical approach described here may be considered an effective treatment for a combined endodontic-periodontal lesion originating from an incomplete VRF and a recurrent periapical lesion.

Implant-associated Vertical Root Fracture in Adjacent Endodontically Treated Teeth: A Case Series and Systematic Review

INTRODUCTION

This study aimed to report a possible effect of the presence of an adjacent implant on the development of a vertical root fracture (VRF) in endodontically treated teeth.

METHODS

A series of 8 cases in 7 patients with teeth diagnosed with VRF after the placement of implants in the adjacent area is described and analyzed. In addition, a comprehensive literature search with strict inclusion and exclusion criteria was undertaken to identify additional clinical studies that assessed this clinical scenario.

RESULTS

The case series analysis revealed that the time from implant placement to the diagnosis of VRF was between 5 and 28 months (average = 11 months). The majority of cases occurred in female patients who received 2 or more implants. Six of the 7 patients were older than 40 years, with an average age of 54 years. The majority of teeth with VRF were premolar or mandibular molar teeth (6/8 teeth). All fractured teeth had been restored with a crown and had a post present, and the quality of the root canal filling was determined to be adequate. The systematic review revealed that implant-associated VRF has not been investigated or reported in the literature yet.

CONCLUSIONS

Based on a systematic review of the literature, this case series, although limited in its extent, is the first clinical report of a possible serious adverse event of implant-associated VRF in adjacent endodontically treated teeth. Additional clinical studies are indicated to shed light on this potential phenomenon.

Does root canal treatment in necrotic pulp or retreatment cases with periapical lesions require anaesthesia? An in vivo clinical study

AIM

To examine whether local anaesthesia is required for treating teeth with necrotic pulps (TNP) and retreatment cases (RCs) associated with periapical lesions.

METHODOLOGY

Root canal treatment was performed in TNP and RCs without the administration of local anaesthesia. Patients were assured that if they experienced pain, local anaesthesia would be provided. Eighty canals, 40 TNP and 40 RCs, were included in the study. Two length measurements were performed: one using an electronic apex locator (EAL), which was defined as the electronic length (EL), and the second, the length at which the patient first reported that a size 15 file was touching the periapical tissues, which was defined as the periodontal length (PL). The difference between these two measurements (Δ = PL - EL) was the parameter studied. Statistical analysis was conducted using two-way anova and paired t-tests. Working length (WL) was defined in this study as being 0.5 mm short of the EL.

RESULTS

EL was shorter than PL in 96% of cases. The mean difference between measurements was 0.78 (±0.11) mm in the TNP group and 0.63 (±0.15) mm in the RC group; the difference was not significant. The distances between the WL and PL were thus 1.28 and 1.13 mm, respectively. In none of the 80 canals did the patient experience any pain, either during the measurements or during the instrumentation procedures.

CONCLUSIONS

When EALs are used, local anaesthesia may not be required for root canal treatment in teeth with necrotic pulps and retreatment cases associated with periapical lesions.

[Use of Cone Beam Computed Tomography in endodontics: rational case selection criteria]

AIM

To present rational case selection criteria for the use of CBCT (Cone Beam Computed Tomography) in endodontics.

MATERIALS AND METHODS

This article reviews the literature concerning the benefits of CBCT in endodontics, alongside its radiation risks, and present case selection criteria for referral of endodontic patients to CBCT.

RESULTS

Up to date, the expected ultimate benefit of CBCT to the endodontic patient is yet uncertain, and the current literature is mainly restricted to its technical efficacy. In addition, the potential radiation risks of CBCT scan are stochastic in nature and uncertain, and are worrying especially in pediatric patients.

CONCLUSIONS

Both the efficacy of CBCT in supporting the endodontic practitioner decision making and in affecting treatment outcomes, and its long term potential radiation risks are yet uncertain. Therefore, a cautious rational decision making is essential when a CBCT scan is considered in endodontics. Risk-benefit considerations are presented.

Evaluation of Root Canal Cleaning and Shaping Efficacy of Three Engine-driven Instruments: SafeSider, ProTaper Universal and Lightspeed LSX

AIM

To compare the cleaning effectiveness and shaping ability of SafeSider, ProTaper Universal and Lightspeed rotary instruments during the preparation of curved root canals in extracted human teeth.

MATERIALS AND METHODS

A total of 63 roots with curved root canals were divided into three groups. Canals were prepared using SafeSider, ProTaper Universal or Lightspeed LSX. Using pre- and post-instrumentation radiographs, straightening of the canal curvatures and loss of working length were determined with a computer image analysis program. The amounts of debris at the apical 5 mm were quantified on the basis of a numerical evaluation scale. The data were analyzed statistically using the two-way analysis of variance (ANOVA).

RESULTS

There was significantly more transportation among the Lightspeed LSX group compared to the SafeSider and ProTaper Universal groups only at the 4 mm level (p < 0.05). The ProTaper Universal instruments performed significantly faster than other groups. No significant differences were observed between the three engine-driven instruments with regards to debris removal.

CONCLUSION

SafeSider, ProTaper Universal and Lightspeed LSX rotary instruments maintained the original canal curvature well at the apical 3 mm and were safe to use. No difference was found in cleaning efficacy and none rendered the apical part of the canal free of debris.

CLINICAL SIGNIFICANCE

SafeSider, ProTaper Universal and Lightspeed LSX rotary instruments are safe to use in curved root canals.

[U.S. Food and Drug Administration (FDA) strengthens warning that non-aspirin non steroidal anti-inflammatory drugs (NSAIDs) can cause myocardial infarctions or strokes: the dentist's perspective]

This short communication is aimed to update dental practitioners regarding the recently published warning of the U.S. Food and Drug Administration (FDA) regarding the risk for severe cardiovascular complications such as myocardial infarction or stroke following the use of non-aspirin non-steroidal anti-inflammatory drugs (NSAIDs).

[Medicolegal aspects of iatrogenic root perforations]

AIM

To retrospectively analyze the medico-legal aspects of iatrogenic root perforations (IRP) that occurred during endodontic treatments.

METHODOLOGY

A comprehensive search in a professional liability insurance database was conducted to retrospectively identify cases of IRP following root canal treatments (RCTs). The complaints were categorized as either financial risk bearing or financial nonrisk bearing, and related demographic and endodontic variables were analyzed.

RESULTS

One hundred and twenty cases of patients with IRP were identified. Twenty six cases (22%) were elective RCTs, and 94 cases (78%) were endodontic treatments performed due to pathologic processes (p < 0.05). Sixty cases (50%) were identified in mandibular molars, significantly more than other tooth locations (P < 0.05). In 102 cases (85%) the outcome was extraction, and in 18 cases (15%) the outcome was an additional treatment (p < 0.05). For both the cases with outcome of extraction and for the cases with an additional treatment, the complaints were judged as financial risk bearing in 95% of the cases.

CONCLUSIONS

latrogenic root perforation is a complication of root canal treatment and may result in tooth extraction and in legal actions against the treating practitioner. Mandibular molars are more prone to medico-legal claims related to root perforations. The patient should be informed of the risks during RCT and should get information on alternative treatments and their risks and prognosis

Postextraction implant in sites with endodontic infection as an alternative to endodontic retreatment: a review of literature

The aim of this literature review is to evaluate the outcomes of implants placed after extraction of teeth with infections of endodontic origin. An electronic search was performed through electronic databases (Medline and Embase) using the terms "immediate implant," "post-extractive implants," "endodontic infection," "infected site," and "extraction socket" combined with the use of Boolean operators ("AND" and "OR"). Only articles on human subjects were considered. At least 12 month of mean follow-up was required for inclusion. No restriction was placed regarding study design. Ten studies were included in this review. Survival rates ranged from 92% to 100%. A total of 497 implants were placed in sites with endodontic infection. In nine studies the use of bone substitutes was associated with immediate implant placement. Because of the low number of included studies and the heterogeneity of study design, more well-designed studies are required to assess the relevance of this treatment alternative.

Implant treatment choice after extraction of a vertically fractured tooth. A proposal for a clinical classification of bony defects based on a systematic review of literature

OBJECTIVES

The objectives of this study were to propose a classification for the bone defects resulting after extraction of a vertically fractured tooth and to review the existing literature about the treatment of such kind of defects by means of dental implants in combination with regenerative procedures.

MATERIALS AND METHODS

An electronic search was performed on biomedical databases using a combination of appropriated search terms combined through the use of Boolean operators. All articles concerning the treatment of peri-implant bone dehiscences and fenestrations through guided bone regeneration (GBR) with at least 6 months follow-up were eligible. Outcomes data extracted from the selected articles were summarized using descriptive tables. A classification of the bone defects associated with vertical root fracture (VRF) was also proposed.

RESULTS

A total of 33 articles were included in the review. Twenty-three articles (814 implants) were about bone dehiscence treatment, ten articles presented the treatment of fenestrations, and ten (429 implants) adopted vertical bone augmentation. The percentage of bone filling was variable among different procedures and defect classification. The use of resorbable membrane was associated with better outcomes than the use of non-resorbable ones.

CONCLUSIONS

Guided bone regeneration for the management of bone defects in the presence of a VRF of the extracted tooth is a viable treatment option. The assessment of bone defect geometry prior to a tooth extraction could be clinically relevant for evaluating the feasibility and the success of immediate implant placement as well as the need of GBR.

Impact of the use of plasma rich in growth factors (PRGF) on the quality of life of patients treated with endodontic surgery when a perforation of sinus membrane occurred. A comparative study

INTRODUCTION

The aim of this retrospective investigation was to evaluate the postoperative quality of life after endodontic surgery in maxillary molars when a sinus membrane perforation occurred and platelet concentrates were used.

MATERIALS AND METHODS

Included patients were treated by microsurgical endodontic treatment in molar and premolar maxillary regions between 2007 and 2010. Patients who fulfilled the inclusion criteria were screened. Data from the quality of life questionnaire were analyzed. The use of plasma rich in growth factors (PRGF) (test group) was compared with a control group when a Schneiderian membrane perforation occurred during endodontic surgery performed with a modern technique in maxillary molars and premolars.

RESULTS

A total of 20 patients (12 in the control group and eight in the test group) fulfilled the inclusion criteria. No differences were evaluated at baseline for clinical parameters. Significantly improved patients' quality of life was observed in the test group considering symptoms as swelling, bad breath or taste, and pain. Functional activities were less impaired in the test group and swelling was significantly higher in the control group. In the test group, pain was significantly lower than the control group during the first 6 days after surgery and also, the consumption of painkillers was lower for patients belonging to the test group even if it was not statistically significant.

DISCUSSION

In general, a small sinus membrane perforation (less than 6 mm) during endodontic surgery did not cause severe complications. The use of platelet concentrates could be effective in reducing the impact on patients' quality of life, decreasing pain and surgery side effects as well as swelling.

Osteotome-Mediated Sinus Lift without Grafting Material: A Review of Literature and a Technique Proposal

Implant rehabilitation of the edentulous posterior maxilla may be a challenging procedure in the presence of insufficient bone volume for implant placement. Maxillary sinus augmentation with or without using grafting materials aims to provide adequate bone volume. The aim of the present study was to systematically review the existing literature on transalveolar maxillary sinus augmentation without grafting materials and to propose and describe an osteotome-mediated approach in postextraction sites in combination with platelet derivative. The systematic review showed that high implant survival rate (more than 96% after 5 years) can be achieved even without grafting the site, with a low rate of complications. Available alveolar bone height before surgery was not correlated to survival rate. In the described case report, three implants were placed in posterior maxilla after extraction of two teeth. An osteotome-mediated sinus lifting technique was performed with the use of platelet derivative (PRGF); a synthetic bone substitute was used to fill the gaps between implant and socket walls. No complications occurred, and implants were successfully in site after 1 year from prosthetic loading. The presented technique might represent a viable alternative for the treatment of edentulous posterior maxilla with atrophy of the alveolar bone though it needs to be validated by studies with a large sample size.

Endoscopic minimally invasive management of a periradicular lesion invading the maxillary sinus

A referred patient presented with a lesion of endodontic origin located at the apex of tooth #27. The tooth had been endodontically treated and re-treated. A periapical radiograph revealed a close relationship between the lesion and the maxillary sinus. A cone-beam computed tomography scan confirmed that the lesion had invaded the sinus cavity. The treatment plan consisted of periapical surgery using an endoscope as a magnification device. Due to a sinus membrane perforation, a new sinus membrane repair technique was performed. Twelve months after surgery, a cone-beam computed tomography scan revealed successful healing of the lesion. The continuous preservation of the sinus physiology was also observed. The use of an endoscope as a magnification device and a tailored technique for sinus membrane management allowed us to achieve a successful treatment outcome in the case of an endodontic lesion invading the maxillary sinus.

[Immediate implant placement in endodontically infected sites: an alternative treatment for compromised teeth]

In certain clinical conditions when endodontic treatment is either impractical or unlikely to improve the previous results, tooth extraction and replacement with a dental implant becomes a viable alternative. Although the presence of active infection has long been considered a major contraindication to the insertion of implants immediately following tooth extraction, several articles assessing this treatment modality reported excellent and promising results. The aim of this literature review is to evaluate and discuss the clinical outcome of implants placed immediately following extraction in endodontically infected sockets. A Medline and EMBASE search was performed to identify articles published from 1966 to 2010 using the keywords "dental implants", "immediate implant", "extraction socket", "infected teeth", "infected site", "infected socket". No restrictions were placed regarding the study design. Only clinical articles with at least 6 months of follow-up were included. The available relevant literature concerning this topic was limited, and based on relatively low level of evidence study designs with limited follow-up periods. However, the data analysis of the selected articles showed that an immediate implant insertion in endodontically infected sites following tooth extraction and careful debridement of the socket, could be a predictable viable technique. Additional large scaled, well-designed studies are required in order to further assess the clinical applications of this treatment alternative.

Medico-legal aspects of altered sensation following endodontic treatment: a retrospective case series

OBJECTIVE

The objective of this study was to analyze cases of liability claims related to persistent altered sensation following endodontic treatments so as to characterize the medico-legal aspects of this complication.

STUDY DESIGN

A comprehensive search of an Israeli professional liability insurance database was conducted to retrospectively identify and analyze cases of persistent altered sensation following endodontic treatment.

RESULTS

Sixteen claims of persistent altered sensation following endodontic treatments were identified and analyzed. The typical profile of a claim was a female patient who underwent an endodontic treatment at a second mandibular molar, which was associated with overfilling. A significant correlation between the tooth location and the suggested cause of nerve injury was found. None of the claims were reported by the practitioners, and all cases were identified as a result of the patient's demand for financial compensation, either directly or by legal actions.

CONCLUSIONS

When a nerve injury is diagnosed, the treating practitioner should be encouraged to seek medical and legal assistance so as to prevent permanent damage and to enable a better medico-legal response.

[Clinical dilemmas concerning immediate implants in the esthetic zone]

Teeth replacement in the esthetic zone is a considerable challenge. Dental implants are usually the preferred treatment alternative for tooth replacement. The present review discusses several clinical issues concerning implant placement in the esthetic area. It is still unclear whether raising a flap at the time of implant placement enhances alveolar crest remodeling. However, a flapless surgical procedure could avoid changes in the free gingival margin and maintain the the attached gingiva width. A submarginal approach not involving the free gingival margin can be applied to treat bone defects with the GBR technique. Implants should be placed as palatal as possible while maintaining optimal restoration emergence profile and the horizontal bone defect filled with a non resorbable material such as bovine bone mineral. Thick periodontal biotype and coronally positioned free gingival margin usually lead to better results. Immediate implant placement in presence of a periapical lesion may be performed, however, sites should be thoroughly debrided prior to implant placement.

Magnification in modern endodontic practice

The use of magnification devices in endodontics is becoming more and more common, with the aim of improving the quality of treatment. The common magnification systems used in modern endodontics are the surgical operation microscope, fiber-optic endoscope, and surgical loupes. The benefits of using magnification devices for conventional endodontic treatment include the increased visualization of the treatment field, enhanced possibilities in locating canals, aid in the removal of separated instruments, diagnosis of root and tooth fractures, perforation repair, and case documentation. In endodontic surgery, the use of magnification improves the ability to locate, clean, and fill the root canal system, thus achieving a predictable outcome. Further evidence-based research might better clarify the advantages and limitations of using magnification in endodontic practice.