Correlation between pulp sensibility and magnetic resonance signal intensity following regenerative endodontic procedures in mature necrotic teeth- a retrospective cohort study.

BACKGROUND: With increasing studies being published on regenerative endodontic procedures (REPs) as a treatment modality for mature necrotic teeth, the assessment of outcomes following regenerative endodontic procedures has become more challenging and the demand for a better understanding of the regenerated tissues following this treatment is rising. The study aimed to correlate cold, electric pulp testing (EPT), and magnetic resonance imaging (MRI) signal intensity (SI) in mature necrotic teeth treated with regenerative endodontic procedures. METHODOLOGY: This retrospective cohort study included eighteen adult patients who experienced tooth necrosis in mature maxillary anterior teeth recruited from the outpatient clinic, Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt from July 2017 until December 2018 with 12 months of follow-up. regenerative endodontic procedures via blood clot were performed. The canals were instrumented by ProTaper Next (PTN) files until final sizes X3 or X5. Biodentine was used as cervical plug material. Pre and post-operative clinical follow-up was done where the patients' responses to cold and electric pulp testing were given a scoring system and were compared to the normal contralateral tooth. Pre and post-operative magnetic resonance imaging signal intensity of both the involved tooth and its contralateral at the middle and the apical thirds of the root canals were assessed after 3, 6, and 12 months. Data was analyzed using the ANOVA, Friedman and Bonferroni tests. Significance was set at a p-value < 0.05. RESULTS: All 18 teeth scored a baseline score of "2" for cold and electric pulp testing. There was a significant difference between scores of the cold test at baseline and 12-month follow-up (p < 0.001). There was a significant difference between scores of the electric pulp testing of baseline and 12-month follow-up (p < 0.001). There was a moderately significant indirect (inverse) correlation between magnetic resonance imaging signal intensity and cold test in both the middle and apical thirds at 12 months. No significant correlations were detected between magnetic resonance imaging signal intensity and electric pulp testingat any of the time intervals (p > 0.05). CONCLUSION: Magnetic resonance imaging is a successful non-invasive method to assess outcomes of regenerative endodontic procedures and correlating it with another reliable method of assessing pulpal responses, cold test, could validate these outcomes. CLINICAL TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov (ID: NCT03804450).

Multimodal Imaging of Dental Pulp Healing Patterns Following Tooth Autotransplantation and Regenerative Endodontic Treatment.

INTRODUCTION: Understanding the healing process of dental pulp after tooth autotransplantation (TAT) and regenerative endodontic treatment (RET) of immature teeth is important both clinically and scientifically. This study aimed to characterize the pattern of dental pulp healing in human teeth that underwent TAT and RET using state-of-the-art imaging techniques. MATERIALS AND METHODS: This study examined 4 human teeth, 2 premolars that underwent TAT, and 2 central incisors that received RET. The premolars were extracted after 1 year (case 1) and 2 years (case 2) due to ankylosis, while the central incisors were extracted after 3 years (cases 3 and 4) for orthodontic reasons. Nanofocus x-ray computed tomography was used to image the samples before being processed for histological and immunohistochemical analysis. Laser scanning confocal second harmonic generation imaging (SHG) was used to examine the patterns of collagen deposition. A maturity-matched premolar was included as a negative control for the histological and SHG analysis. RESULTS: Analysis of the 4 cases revealed different patterns of dental pulp healing. Similarities were observed in the progressive obliteration of the root canal space. However, a striking loss of typical pulpal architecture was observed in the TAT cases, while a pulp-like tissue was observed in one of the RET cases. Odontoblast-like cells were observed in cases 1 and 3. CONCLUSIONS: This study provided insights into the patterns of dental pulp healing after TAT and RET. The SHG imaging sheds light on the patterns of collagen deposition during reparative dentin formation.

Clinical and radiographic outcomes of regenerative endodontic procedures for traumatized permanent necrotic teeth with apical periodontitis and external root resorption.

AIM: This clinical study was undertaken to assess the effect of treatment with regenerative endodontic procedures (REPs) on 20 teeth with pulp necrosis, apical periodontitis, and external root resorption (ERR). METHODOLOGY: Teeth were treated with REPS utilizing the American Association of Endodontists (AAE) protocol. Quantitative assessment of changes in radiographic root area (RRA) were statistically analysed to assess changes in root dimensions after an average follow-up period of 3 years. RESULTS: All 20 teeth survived, 14 teeth (70%) were classified successful, and only 1 tooth (5%) failed throughout the study period. Based on the radiographic examination, all 20 teeth showed complete repair of the periapical lesions and arrested ERR. However, 5 teeth (25%) subsequently developed replacement resorption. The RRA between baseline and 3-year follow-up showed a significant difference for the total 20 teeth (p = .009). An analysis according to the trauma type and the extra-oral time showed the RRA increase was significantly different in the non-avulsion group (p = .015) and for the avulsion group with an extra-oral time less than 60 min (p = .029). The RRA increase was not statistically significant in the avulsion group of extra-oral time more than 60 min (p = .405). Nine teeth (45%) and 10 teeth (50%) responded to cold and electric pulp testing, respectively. CONCLUSIONS: Within the limitations of this study, the favourable outcomes of REPs were further confirmed for traumatized permanent necrotic teeth with ERR in terms of periapical lesion healed and a significant increase in RRA. The study contributes further evidence of the role of REPs in arresting ERR.

Radiographic outcomes and prognostic factors in nonvital immature permanent teeth after apexification with modified calcium hydroxide paste: a retrospective study.

OBJECTIVE: To assess the radiographic outcomes and prognostic factors in nonvital immature permanent teeth after apexification with modified calcium hydroxide paste. MATERIALS AND METHODS: Clinical and radiographic data were collected from 115 necrotic immature permanent teeth (71 caused by trauma and 44 caused by dens evaginatus) treated with apexification using a modified calcium hydroxide. Postoperative root morphology and changes in radiographic root area (RRA) on periapical radiographs were determined and statistically evaluated. Regression analysis was performed to identify factors associated with the outcomes of apexification. RESULTS: The average time for a calcified barrier formation was 10.66 ± 6.37 months. The root morphology after apexification with calcium hydroxide + iodoform paste was similar to that previously described after calcium hydroxide apexification. Compared with the trauma cases, the dens evaginatus cases revealed more type I (40.91% vs 16.9%) and less type II morphology (45.45% vs 67.61%). Although the changes in RRA were limited, the dens evaginatus cases showed greater increment of RRA than the trauma cases (4.12% ± 5.58% vs 0.70% ± 5.21%, P < 0.001). A significant association was found between the preoperative stage of root development and postoperative percentage change in RRA (P < 0.001). CONCLUSIONS: Teeth caused by dens evaginatus had better outcomes after apexification than teeth caused by trauma. Early stages of root development were associated with superior radiographic outcomes. CLINICAL RELEVANCE: Apexification provided reliable outcomes in the treatment of immature teeth with pulp necrosis and apical periodontitis, even though the root development is limited. Treatment decision should be made with comprehensive evaluation of prognostic factors.

Endodontic pulp revitalization in traumatized necrotic immature permanent incisors: Early failures and long-term outcomes-A longitudinal cohort study.

AIM: This prospective cohort study evaluates clinical and radiographical outcomes of endodontic pulp revitalization (PR) of traumatized necrotic incisors. METHODOLOGY: Pulp revitalization was performed in 75 traumatized necrotic immature incisors from 71 patients. The radiographic outcome measures were continued root formation (width and length), root resorption, apex closure, periapical index, and root development stage. The clinical outcome measures were percussion pain, palpation pain, pathological tooth mobility, swelling, sinus tract, ankylosis, crown discolouration, response to pulp sensitivity test, and subjective pain. Treatment outcomes were categorized as a success based on the absence of clinical symptoms and when radiographic evidence was present for apical healing and continued root development. The performed statistical tests were repeated measures anova, pairwise comparisons of interactions (t-test), McNemar's test, and linear regression model. RESULTS: In 45 of 75 teeth (60%), PR was successful with the resolution of clinical and radiographic signs and continued root development. PR failed due to the absence of bleeding (n = 19) and persistent infection (n = 11). PR showed statistically significant increases in root length (11%), and dentinal wall thickness (30%), root maturation (pre-operative 3.38 [CI 1.88; 4.88]; post-operative 4.04, [CI 2.56; 5.52]) apical closure (71.4%), healing of pre-operative apical periodontitis (100%), and healing of pre-operative inflammatory root resorptions (100%). Three predictive variables for continued root maturation were identified - root development stage at entry (p = .0001, ß 0.649), [CI 0.431; 0.867], trauma to the soft tissues (p = .026, ß -0.012), [CI -0.0225; -0.015], and pre-operative dentinal wall thickness (p = .009, ß -0.001); [CI -0.001; 0.0001]. CONCLUSIONS: Our findings indicate that PR provides satisfactory clinical and radiographical outcomes in traumatized necrotic incisors. The failed cases were related to lack of bleeding and persistent infections, indicating that new techniques are needed to improve the predictability of PR.

Combined conventional and regenerative treatment in molars with coexistent closed and open apices: A case series.

Regenerative endodontic treatment (RET) may not be suitable in some necrotic young permanent molars due to coexistent roots with closed and open apices, and/or inadequate apical bleeding in one or more roots. Here, we present a combined treatment approach utilising conventional root canal treatment in the closed-apex roots and RET on the open-apex roots of necrotic young molars. The closed-apex roots of 8 molars received root fillings, and their open-apex roots were treated with a regenerative endodontic procedure. In another molar, the failed RET on one root was retreated by conventional root canal filling, preserving other revitalised roots. After 4-6 years, all teeth showed periapical healing in the absence of clinical symptoms. The combined conventional and regenerative treatment approach can yield favourable healing outcomes in necrotic, young molar roots with different levels of apical closure. Likewise, failed revitalised roots can be retreated separately with conventional root filling.

Radiographic differences observed following apexification vs revascularization in necrotic immature molars and incisors: a follow-up study of 18 teeth.

PURPOSE: To evaluate the effectiveness of apexification versus revascularization in the treatment of necrotic immature teeth and determine which strategy affords the greatest radiological success rate. METHODS: An analysis was made of 18 teeth subjected to mineral trioxide aggregate (MTA) apical plugging and regenerative endodontic treatment, assessing healing of the apical lesions and the changes in root dimensions. RESULTS: Significantly greater root growth was observed with revascularization in terms of the percentage change in length (12.75% at 6 months) and dentin thickness (34.57% at 6 months) (p < 0.05). There were no significant differences between the two treatments in terms of the apical healing scores after 6 months of follow-up (p > 0.05). CONCLUSION: Apexification with an MTA apical plug and pulp regeneration are reliable treatments for non-vital immature teeth. The radiographic outcomes are comparable between the immature teeth subjected to MTA apexification versus those subjected to revascularization. The results of the present study indicate a greater increase in root length and width with regenerative endodontic treatment.

Regenerative endodontic procedures for the treatment of necrotic mature teeth: A preliminary randomized clinical trial.

AIM: This preliminary randomized, prospective, controlled trial aimed to compare the clinical and radiographic outcomes of two regenerative endodontic procedures (REPs), revitalization and a platelet-rich fibrin (PRF)-based technique, in the treatment of mature permanent teeth with necrotic pulps. METHODOLOGY: The trial has been reported according to the Preferred Reporting Items for Randomized Trials in Endodontics 2020 guidelines. The study protocol was registered at the clinical trial registry (ClinicalTrials.gov) with identifier number NCT04158232. Twenty patients with mature necrotic anterior teeth with large periapical lesions were randomly allocated into two groups (n = 10): group I, treated with revitalization with the blood clot (BC) technique and group II, treated with a PRF-based technique. The follow-up was for 12 months. Periradicular healing was assessed using standardized radiographs taken at baseline, and at 6 and 12 months after treatment. An electric pulp tester was used to assess whether pulp sensibility had been regained during the follow-up period. Statistical analysis was conducted using Mann-Whitney test and Wilcoxon test for non-parametric data. For parametric data, repeated measures analysis of variance was used. The significance level was set at p ≤ .05. RESULTS: There was a significant increase in periradicular healing in both groups at 6 and 12 months, compared to that at baseline, with no significant difference between the studied groups after 12 months (p = .143). There was a significant difference between the tooth sensibility readings at baseline, 6-month and 12-month follow-up timepoints (p < .001). CONCLUSIONS: The findings of this preliminary trial indicate the potential for using REPs, such as revitalization or PRF-based techniques, as treatment options for mature teeth with necrotic pulps. A higher level of evidence obtained through adequately powered clinical trials and longer follow-up periods are required to conclusively validate the different outcomes of REPs.

Herpes Zoster and association with pulp necrosis and development of apical periodontitis - a review and presentation of two case reports.

The varicella zoster virus as an aetiological agent for endodontic disease is not a well-recognised entity despite several published case reports. While advances in DNA molecular analysis techniques (PCR) have contributed to the current understanding of the potential role of the varicella zoster virus in the initiation and progression of endodontic disease, a review indicates a need for ongoing research. Case reports are presented of two female patients with a history of herpes zoster who developed pulp necrosis, with one patient progressing to apical periodontitis. Both patients received non-surgical endodontic therapy, followed by intra-coronal bleaching in one of the patients due to tooth discolouration which developed during the prodromal and acute phases of the herpes zoster infection. Clinical and radiographic examinations at 23 and 22 years, respectively, showed the affected teeth to be retained in an asymptomatic and aesthetically satisfactory state with no radiographic evidence of apical pathosis.

Long-Term Follow-up for Immature Teeth Treated with Regenerative Endodontic Procedures That Underwent Orthodontic Treatment.

Although regenerative endodontic procedures (REPs) have become one of the widely accepted treatment modalities for necrotic immature teeth with apical periodontitis, little is known about the long-term outcomes and the effect of orthodontic tooth movement on this procedure. This report presents a case that underwent two REPs and orthodontic treatment over a period of seven years. A 9-year-old male was referred for evaluation of traumatized maxillary central incisors. Based on clinical and radiographic examinations, a diagnosis of pulp necrosis with acute apical abscess was established. REP was performed for both teeth, and the patient was brought in for follow-up annually. Orthodontic treatment was performed during the follow-up period. Annual follow-up visits demonstrated complete resolution of signs and symptoms of disease with the thickening of the roots. At the six-year follow-up visit, the patient presented with a sinus tract and periapical radiolucency. A second REP was performed for both teeth. The one-year recall visit after the second REP revealed complete resolution of clinical symptoms and radiographic signs of healing of apical pathology with further development of the roots. In conclusion, the effect of orthodontic treatment on teeth undergoing REP should be investigated and yearly follow-up visits should be recommended for patients undergoing REP as this case showed signs of deterioration six years after the treatment.

Regenerative Endodontic Procedure of Immature Permanent Teeth with Leukocyte and Platelet-rich Fibrin: A Multicenter Controlled Clinical Trial.

INTRODUCTION: The aim of this nonrandomized, multicenter controlled clinical trial was to evaluate the impact of leukocyte-platelet-rich fibrin (LPRF) on regenerative endodontic procedures (REPs) of immature permanent teeth in terms of periapical bone healing (PBH) and further root development (RD). METHODS: Healthy patients between 6-25 years with an inflamed or necrotic immature permanent tooth were included and divided between the test (= REP + LPRF) and control (= REP-LPRF) group depending on their compliance and the clinical setting (university hospital or private practice). After receiving REP ± LPRF, the patients were recalled after 3, 6, 12, 24, and 36 months. At each recall session, the teeth were clinically and radiographically (by means of a periapical radiograph [PR]) evaluated. A cone-beam computed tomographic (CBCT) imaging was taken preoperatively and 2 and 3 years postoperatively. PBH and RD were quantitatively and qualitatively assessed. RESULTS: Twenty-nine teeth with a necrotic pulp were included, from which 23 (9 test and 14 control) were analyzed. Three teeth in the test group had a flare-up reaction in the first year after REP. Except for 2 no shows, all the analyzed teeth survived up to 3 years after REP, and, in case of failure, apexification preserved them. Complete PBH was obtained in 91.3% and 87% of the cases based on PR qualitative and quantitative evaluation, respectively, with no significant difference between the groups with respect to the baseline. The PR quantitative change in RD at the last recall session with respect to the baseline was not significant (all P values > .05) in both groups. The qualitative assessment of the type of REP root healing was nonuniform. In the test group, 55.6% of the teeth presented no RD and no apical closure. Only 50% of the 14 teeth assessed with CBCT imaging presented complete PBH. Regarding volumetric measurements on RD 3 years after REP for the change with respect to the baseline in root hard tissue volume, mean root hard tissue thickness, and apical area, the control group performed significantly in favor of RD than the test group (P = .03, .003, and 0.05 respectively). For the volumetric change 3 years after REP with respect to the baseline in root length and maximum root hard tissue thickness, no significant difference (P = .72 and .4, respectively) was found between the groups. The correlation between the PR and CBCT variables assessing RD was weak (root lengthening) to very weak (root thickening). CONCLUSIONS: REP-LPRF seems to be a viable treatment option to obtain PBH and aid further RD of necrotic immature permanent teeth. Caution is needed when evaluating REP with PR.

Efficacy of i-PRF in regenerative endodontics therapy for mature permanent teeth with pulp necrosis: study protocol for a multicentre randomised controlled trial.

BACKGROUND: Dental pulp necrosis, a common health problem, is traditionally treated with root canal therapy; however, it fails in restoring the vitality of damaged pulp. Most studies regarding regenerative endodontic therapy (RET) are limited to the treatment of immature necrotic teeth. Given that injectable platelet-rich fibrin (i-PRF) has shown great potential in regenerative medicine as a novel platelet concentration, this study is designed to explore whether i-PRF can serve as a biological scaffold, extending the indications for RET and improving the clinical feasibility of RET in mature permanent teeth with pulp necrosis. METHODS: This is a randomised, double-blind, controlled, multicentre clinical trial designed to evaluate the clinical feasibility of RET for mature permanent teeth with pulp necrosis and to compare the efficacy of i-PRF and blood clots as scaffolds in RET. A total of 346 patients will be recruited from three centres and randomised at an allocation ratio of 1:1 to receive RET with either a blood clot or i-PRF. The changes in subjective symptoms, clinical examinations, and imaging examinations will be tracked longitudinally for a period of 24 months. The primary outcome is the success rate of RET after 24 months. The secondary outcome is the change in pulp vitality measured via thermal and electric pulp tests. In addition, the incidence of adverse events such as discolouration, reinfection, and root resorption will be recorded for a safety evaluation. DISCUSSION: This study will evaluate the clinical feasibility of RET in mature permanent teeth with pulp necrosis, providing information regarding the efficacy, benefits, and safety of RET with i-PRF. These results may contribute to changes in the treatment of pulp necrosis in mature permanent teeth and reveal the potential of i-PRF as a novel biological scaffold for RET. TRIAL REGISTRATION: ClinicalTrials.gov NCT04313010 . Registered on 19 March 2020.

Clinical and Radiographic Outcomes of Regenerative Endodontic Procedures in Traumatized Immature Permanent Teeth: Interappointment Dressing or Single-Visit?

INTRODUCTION: More data are needed before affirming that single-visit approaches are effective and safe for regenerative endodontic procedures (REPs). This study compared clinical and radiographic outcomes of REPs between interappointment dressing or single-visit protocols. METHODS: Twenty young patients presenting traumatized immature teeth with pulp necrosis were divided into 2 groups. Teeth were submitted to 6% sodium hypochlorite and 2% chlorhexidine irrigation and to 17% EDTA use before blood clot induction. In the interappointment dressing group (n = 11), calcium hydroxide was used with 2% chlorhexidine gel for 21 days before scaffold induction. In the single-visit group (n = 9), the scaffold was induced during the only appointment. Patients were followed up for 24 months. Primary, secondary, and tertiary outcomes were assessed by 3 independent evaluators. Preoperative and follow-up radiographs were assessed for quantitative measurements of the apical diameter, root width, root length, and cervical barrier placement and compared between groups using the t test or Mann-Whitney U test. Categoric variables were assessed with the G test and the Fisher exact test and continuous variables with the Mann-Whitney U test. Statistical significance was set at 5%. RESULTS: One tooth showed persistence of infection. No difference was observed in cervical barrier placement (P > .05); between groups regarding primary, secondary, and tertiary outcomes (P > .05); and in parameters of quantitative radiographic outcomes (P > .05). CONCLUSIONS: Completing REPs with an interappointment dressing or a single-visit protocol presented similar clinical and radiographic outcomes. A single-visit protocol of REPs using 6% sodium hypochlorite, 2% chlorhexidine, and 17% EDTA permitted satisfactory outcomes in necrotic immature permanent teeth.

CBCT influences endodontic therapeutic decision-making in immature traumatized teeth with suspected pulp necrosis: a before-after study.

OBJECTIVE: To evaluate the impact of cone-beam computed tomography (CBCT) in endodontic therapeutic decision-making of immature traumatized teeth with suspected pulp necrosis. METHODS: Over two years, consecutive patients with a dental trauma in their front teeth (apex >0.5 mm) and with suspected pulp necrosis based on clinical and radiographic findings were referred to a specialist clinic in Sweden. Fifteen patients aged 6-13 (18 teeth) were included and clinically examined by an endodontist. Intraoral radiographs and CBCT examinations were obtained. Five practitioners, three endodontists and two residents in endodontics, used these examinations to determine the most appropriate treatment for the 18 cases (all central incisors) on two occasions scheduled 19 weeks apart. On the first occasion, the practitioners had access to clinical information and the intraoral radiographs ('before' CBCT); on the second occasion, the practitioners had also access to a radiologist report and the CBCT images ('after' CBCT). Their treatment plans - no treatment, watchful waiting, endodontic orthograde treatment, or extraction - were made anonymously and independently. Results were analysed using descriptive statistics and Wilcoxon signed-rank test. RESULTS: 'After' CBCT, practitioners changed treatment plans in 30% of the 90 assessments, 74% of which were more aggressive (p = 0.028). In 49% of the assessments, practitioners who chose the watchful and waiting treatment plan 'before' CBCT changed to a more aggressive therapy such as endodontic orthograde treatment and extraction 'after' CBCT (p = 0.005). CONCLUSION: This study provides evidence that CBCT influences endodontic therapeutic decision-making regarding immature traumatised teeth with suspected pulp necrosis, chiefly when expectant management (i.e., watchful and waiting) was selected before access to CBCT.

Presentation and non-surgical endodontic treatment of two patients with X-linked hypophosphatemia: a case report.

AIM: To describe two patients with X-linked hypophosphatemia presenting with spontaneous signs of pulpal necrosis in multiple intact teeth. The presentation and management are discussed, along with the diagnostic and endodontic treatment challenges. SUMMARY: Two young male patients with X-linked hypophosphatemia were referred to the Department of Restorative Dentistry at the Edinburgh Dental Institute, UK for management of dental infection. Both patients were referred due to their unusual clinical presentation and abnormal root canal morphology. They subsequently presented on multiple occasions with pain or sinus tracts over a 3- and 5-year period whilst under care. Clinical examination revealed intact teeth with buccal swellings, draining buccal sinuses and negative responses to pulp sensibility testing. Radiographic examination, generally consisting of periapical radiographs, revealed intact teeth with a range of unusual morphological features including large pulp chambers, wide canals, short roots and open apices, all with associated periapical radiolucencies. Due to the unusual morphology, some teeth required apexification with a mineral trioxide aggregate plug. Patient 1 underwent root canal treatment on teeth 21 and 43 over a 3-year period. Patient 2 underwent root canal treatment on 10 permanent teeth over a 5-year period. At follow-up, both patients were asymptomatic and clinically the teeth had no signs of infection or periapical inflammation. Radiographic examination confirmed complete resolution of the apical radiolucencies on 11 out of 12 teeth. Favourable outcomes have been demonstrated up to a follow-up of 4.5 years. KEY LEARNING POINTS: Patients with X-linked hypophosphatemia may present with 'spontaneous' signs of pulp necrosis in multiple teeth in the absence of caries and trauma posing a diagnostic challenge. Abnormal morphological features, including wide canals and open apices, may present challenges during root canal treatment. Outcomes demonstrate that an appropriate root canal treatment protocol, including the application of apexification procedures, may be implemented to successfully manage such cases.

Regenerative endodontic therapy: a follow-up of 47 anterior traumatised teeth.

PURPOSE: To collect long-term survival data in anterior traumatised teeth on the outcome of Regenerative Endodontic Treatments (RET) with a network of dentists working in different clinics to overcome the problem of anecdotical evidence. METHODS: The seven dentists from Paediatric REsearch Project (PREP) performed RET treatments following the same protocol in five different secondary dental care clinics in the Netherlands. Treatment resulting in pain, apical problems, sinus tracts, resorption or fracture were considered as failure of treatment. RESULTS: 47 teeth in 38 children were treated between January 2009 and September 2017 and had at least 6 month follow-up (mean 35 months). Apical closure was seen in 27 teeth (25 cases) and root length growth in 6 teeth (6 cases). Thickening of the root walls was seen in 20 teeth (20 cases) and obliteration of the root canal in 30 teeth (25 cases). Of 38 teeth with apical inflammation at the start of treatment, no radiographic sign of apical inflammation was visible at 3 months in 13 of 28 teeth; taking up to 42 months for radiographic signs of apical inflammation to be not visible. Nineteen of 35 teeth showed discoloration at the beginning of treatment. After 18 months two teeth showed signs of ankylosis, but were still functional. After 36 months one more tooth showed signs of new apical inflammation and 2 months later it was extracted. CONCLUSIONS: With three failures in 47 treated teeth, RET seems to be a promising treatment for difficult to treat anterior traumatised teeth with an open apex.

Regenerative endodontics: a promising tool to promote periapical healing and root maturation of necrotic immature permanent molars with apical periodontitis using platelet-rich fibrin (PRF).

PURPOSE: Currently, mineral trioxide aggregate (MTA) apexification is recommended as the preferred treatment for permanent anterior immature necrotic teeth. Apexification treatment does not enable further development and maturation of the teeth, resulting in short roots with thin root canal walls, that often are prone to cervical fractures. This study presents the regenerative endodontic procedure (REP) as an alternative treatment for immature necrotic molars with apical periodontitis or a chronic apical abscess. REP enables periapical healing as well as root lengthening and widening of the dentinal root canal walls. CASE SERIES RESULTS: Six immature first molars teeth (five mandibular, one maxillary) with apical periodontitis or chronic apical abscess were treated with REP. Patients underwent periodic follow-up visits every 3 months the first year and twice a year thereafter. The final clinical examination revealed no symptoms, no gingival pockets, and no sensitivity to percussion. Cold sensitivity tests were negative. Radiographs revealed full periapical healing in all the treated molars, remarkable root lengthening, and dentinal wall thickening. CONCLUSION: REP with PRF is feasible and may have some advantages over MTA apexification since it facilitates root elongation, dentinal thickening of the root canals walls, and narrowing of the apical foramen.

Three-dimensional qualitative and quantitative analyses of the effect of periradicular lesions on the outcome of regenerative endodontic procedures: A prospective clinical study.

OBJECTIVES: Qualitative and quantitative evaluation of the outcomes of regenerative endodontic procedure (REP) on human immature necrotic teeth with apical periodontitis using cone-beam computed tomography (CBCT) MATERIALS AND METHODS: Immature permanent teeth (n = 50) with necrotic pulp and periradicular pathosis were treated with a cell-homing concept-based REP. Following the procedure, a limited field-of-view CBCT scan was obtained. At each recall session (6, 12, 18 months), clinical tests were performed, and a digital periapical radiograph was taken. When significant radiographic changes were evident in the follow-up, a final CBCT scan was taken for qualitative and quantitative assessment. These initial and follow-up CBCT scans were assessed for quantification of changes in root length, pulp space diameter and periradicular lesion size. The data were statistically analysed using t test, one-way ANOVA, post hoc test and paired t test (P = 0.05). RESULTS: Of the teeth, 94.6% were clinically successful based on the lack or regression of signs and symptoms after 48 months follow-up. REP resulted in a statistically significant increase in root length, decrease in pulp space diameter and periradicular radiolucency (P < 0.05). CBCT images illustrated various patterns of root maturation including an increased thickening of the canal walls and continued root maturation (37.1%), continued root development with the apical foramen remaining open (57.1%), severe calcification (obliteration) of the canal space (2.9%) and hard tissue barrier formation in the canal space between the coronal plug and the root apex (2.9%). CONCLUSION: This study highlighted that the expected outcome of radiographic root development was less predictable when immature permanent teeth with periradicular pathosis were treated with REP. CLINICAL RELEVANCE: The size and extent (expansion/destruction of the cortical plate) of periradicular lesions and abscesses influence the outcome of REP. These factors must be taken into consideration during treatment planning.

Regenerative endodontic therapy of immature permanent molars with pulp necrosis: a cases series and a literature review.

AIM: To present the application and the outcome of the regenerative endodontic therapy (RET) in a series of symptomatic immature mandibular molars with pulp necrosis and apical periodontitis and to review the relevant literature for the documentation of the procedure as a potential treatment option. METHODS: Three young male patients were referred with pain in the left mandibular region resulting from pulp necrosis and apical periodontitis of the first permanent molar. Regenerative endodontic approach was performed for the complete resolution of the lesions and the thickening of the apical root canal walls. The databases of Medline, Pubmed and Google Scholar were also searched for articles in which a regenerative approach has been undertaken for the endodontic management of immature permanent molars with pulp necrosis and apical periodontitis. RESULTS: Follow-up examinations showed that the teeth remained functional without any signs or symptoms. Final radiographic examination at 12, 18 and 36 months, respectively, revealed complete resolution of the lesions and complete apical closure in the two out of three cases. The search of the literature revealed the existence of only 25 clinical articles in which necrotic immature molars were treated by the regenerative approach. The total number of the treated teeth were 46. CONCLUSIONS: Regenerative endodontic approach may be applied in posterior non-vital molar teeth with a possible favorable outcome. However, the literature support for the documentation of the procedure as a predictable and reproducible treatment option in posterior immature molar teeth is at present limited.

Radiographic evaluation of immature traumatized incisors following different endodontic treatments.

BACKGROUND/AIMS: Indirect pulp capping, pulpotomy, and apexification are three common endodontic treatments for immature traumatized incisors. They all affect tooth root development to some extent. The aim of this retrospective study was to compare the influence of these treatments on root development of immature permanent incisors following dental trauma. MATERIALS AND METHODS: Twenty-one indirect pulp capping, 48 pulpotomy, and 58 apexification cases with a mean age of 8.4 ± 1.0 years and median follow up of 12 months were included. NIH ImageJ with TurboReg plug-in was used to correct angular differences between the pre-operative and recall periapical radiographs, and to calculate variations of root length, dentin wall thickness, and apical closure. Kruskal-Wallis ANOVA followed by pairwise comparisons was applied to compare the radiographic variations. The type of apical closure was assessed qualitatively and analyzed using Fisher's exact test. RESULTS: The apexification group had a lower trend toward apical closure than the other two groups (P < .05). It also showed thinner dentin wall thickness compared with the pulpotomy group (P = .001). There was no significant difference between pulpotomy and indirect pulp capping in the trend to apical closure (P > .05) or dentin wall thickness (P = .775). There was no significant difference in the variation of root length among the three groups (P = .06). There was a moderate correlation between the treatment and the type of apical closure (Cramer's V Coefficient = .375). Pulpotomy tended to form a normal apical constriction rather than a calcific barrier while apexification showed the opposite inclination. Indirect pulp capping had no specific inclination toward any type of apical closure. CONCLUSIONS: Apexification resulted in an abnormal root development mostly by affecting the dentin wall thickness and apical closure. Pulpotomy was beneficial for normal root development of immature traumatized teeth.