Apical Closure Research Articles

Clinical efficacy of platelet-rich fibrin, injectable platelet-rich fibrin, and advanced platelet-rich fibrin in regenerative endodontics: A case series

Background: This series investigates the efficacy of regenerative endodontic therapy (RET) using various platelet-rich fibrin (PRF) formulations in treating apical periodontitis and necrotic pulp in immature permanent teeth. Aim: This study aims to evaluate the effectiveness of different PRF formulations in RET. Materials and Methods: Three cases involving patients aged 15–16 with immature teeth and necrotic pulp were treated with RET using PRF, injectable PRF, and advanced PRF. The procedure included inducing bleeding with a Hedstrom file, applying PRF variants, and sealing with mineral trioxide aggregate and composite resin. Patients were followed up at 1, 3, 6, 12 and 18 months. Results: Radiographic evidence showed apical closure, root maturation, and healing of periapical tissues in all cases. However, pulp sensibility tests were negative. Conclusion: RET using PRF variants promotes root development and apical healing in immature teeth. Further research with larger sample sizes is needed to understand these therapies’ potential and limitations.

Time-Dependent Morphological Changes in Traumatic Immature Teeth With Necrotic Pulps Following Regenerative Endodontic Treatment: A Retrospective Study.

Regenerative endodontic treatment is a promising approach for healing periapical lesions and continuous root maturation. Although previous studies have reported its outcomes, the dynamics of morphological changes over time remain unclear. Therefore, this study aimed to evaluate changes in the periapical status and root dimensions over a 60-month follow-up period. The follow-up duration, periapical status changes, calcific barrier formation, degree of apical closure and radiographic root area changes were compared with those of the last follow-up in this retrospective study. Radiographic root area changes were calculated as the difference between the total root and total canal areas. Fifty-eight patients (81 teeth) underwent regenerative endodontic treatment during the study period, of whom 32 patients (36 teeth, 62%) were included. The survival and success rates of the treated teeth were 100% and 94.4%, respectively. All teeth developed a calcific bridge in the cervical third of the root canal, indicating the presence of vital tissue. Apical narrowing (partial or total) was observed in 75% of the cases. The root maturation stage affected the percentage increase in the radiographic root area. Teeth in Cvek stages II-III showed a higher radiographic root area increase than more mature teeth. All tooth radiographic root areas increased significantly in the initial 20 months of the treatment and moderately thereafter. Regenerative endodontic treatment is a safe approach for traumatised immature teeth. The presence of a radiographic calcified bridge may be an early indication of treatment success. The main complete tooth morphological changes occur after approximately 20 months posttreatment. These findings may help clinicians better understand the time-dependent changes in the root morphology after treatment, improve the follow-up schedule and predict the progress of healing during follow-up visits.

Evaluation of microleakage of mineral trioxide aggregate and biodentine as apical barriers in simulated young permanent teeth

BackgroundApexification is a procedure that promotes apical closure by forming mineralized tissue in the apex region of a nonvital young permanent tooth. Calcium silicate-based cement like Mineral trioxide aggregate (MTA) and Biodentine are commonly employed as apical barriers to facilitate this process. Microleakage, defined as the leakage along the junction between the canal wall and filling material, is a crucial aspect to assess in MTA and Biodentine applications as apical barriers, as it directly impacts the prevention of bacterial seepage and maintenance of structural integrity. The current study aims to assess the microleakage of MTA and Biodentine when used as apical barriers in simulated young permanent teeth.MethodsFrom a total of 128 extracted teeth, 114 were selected for the study and randomly allocated into three groups: G1 (MTA), G2 (Biodentine), and G3 (Control), with 38 teeth per group. After excluding 5 teeth from each group due to issues such as canal calcification, breakage during sectioning, and procedural errors, 33 teeth were analyzed to ensure equal distribution. To simulate young permanent teeth, samples were instrumented using a person-reamer with a diameter of 1.7 mm. A 4 mm thick apical plug of MTA and Biodentine was placed in G1 and G2, respectively, while G3 was the control group. Apical microleakage in all experimental groups was assessed using a dye penetration method. Specimens were longitudinally sectioned and examined under a stereomicroscope with graded eyepiece.ResultsThe Kruskal-Wallis test revealed variations in mean apical microleakage among the groups: G1 recorded 0.67, G2–0.16, and G3–1.62, with G2 showing the lowest value and G3 group exhibiting the highest.ConclusionsBiodentine was found to excel in its ability to create a secure seal and function effectively as an apical barrier in simulated young permanent teeth. These results underscore its potential as a highly efficient material for dental applications, particularly in scenarios requiring reliable sealing and barrier formation in the root canal system of developing permanent teeth.

THE EFFECT OF CALCIUM HYDROXIDE PARTICLE SIZE ON DENTIN TUBULI HARDNESS

Background: Calcium hydroxide (Ca(OH)2) is an effective root canal treatment, with calcium and hydroxyl ions effectively released on day 7. However, prolonged use can diminish dentinal tubule hardness and dissolve the hydroxyapatite crystals within them. Nanoparticle Ca(OH)2 demonstrated superior antimicrobial activity compared to conventional Ca(OH)2 because of its deeper penetration into the dentinal tubules.. Purpose: This study aimed to evaluate the effect of particle size on dentinal tubule hardness. Methods: True experiment with fifteen premolars with one root canal, no caries, and apical closure were divided into three treatment groups: conventional Ca(OH)2 (group 1, n=5), Ca(OH)2 nanoparticles (group 2, n=5), and untreated (control group), n=5. All samples were incubated for 7 days, and hardness was measured using a micro-Vickers hardness tester at 1/3 of the root canal. Kruskal-Wallis test followed by Mann-whitney post hoc analysis was used to compare the mean microvickers hardness values among different groups. The level of significance was set at p<0.05. Results: The results showed that there was significant difference between conventional Ca(OH)2 (73.00 ± 2.71) and Ca(OH)2 nanoparticles (67.40 ± 0.62) p=0.01 and the control group (70.68 ± 1.70; p>0.05) and Ca(OH)2 nanoparticles p=0.03. Conclusions: The use of Ca(OH)2 nanoparticles as an intracanal medicament for 7 days reduced dentin microhardness, whereas conventional Ca(OH)2 did not result in any change in microhardness. Particle size affects the hardness of dentinal tubules.

Regenerative potential of mesoporous silica nanoparticles scaffold on dental pulp and root maturation in immature dog’s teeth: a histologic and radiographic study

ObjectiveTo evaluate histologically and radiographically the potential of dog’s immature roots with apical periodontitis to regenerate after regenerative endodontic treatment using mesoporous silica nanoparticles (MSNs) with/without bone morphogenic protein (BMP-2) as scaffolds.MethodsIn 4 mongrel dogs, 56 immature teeth with 96 roots were infected, resulting in necrotic pulps and periapical pathosis. According to the evaluation time (Group I = 30 days and Group II = 90 days), 90 roots were divided into two equal groups (45 roots each) and 6 roots used to replace any lost root during the procedure. The two main groups were further divided according to treatment protocol into 5 subgroups (9 roots each): blood clot (BC subgroup), mesoporous silica nanoparticles scaffold only (MSNs subgroup), mesoporous silica nanoparticles impregnated with BMP2 (MSNs + BMP2 subgroup), infected teeth without treatment (+ ve control subgroup) and normal untouched teeth (-ve control subgroup). All teeth surfaces were coated with Tincture iodine and calcium hydroxide was applied prior to treatment protocols. Then, teeth were restored with glass ionomer filling to seal the remaining part of the access cavity. Radiography evaluation of the increase in root length, root thickness and occurrence of apical closure were performed. Following the sacrifice of the two dogs at each time of evaluation, histopathological analysis was performed and included the inflammatory cells count, bone resorption, tissue ingrowth, deposition of hard tissue, and closure of the apical part. All data were statistically analyzed.ResultsCompared to BC subgroup, MSNs and MSNs + BMP-2 subgroups exhibited significant higher increase in root length and thickness as well as higher vital tissue in-growth and new hard tissue formation in group II (P < 0.05). MSNs + BMP-2 subgroup had significant higher increase in root length and thickness as well as significant lower inflammatory cell count than MSNs subgroup in both groups (P < 0.05). There were no significant differences between MSNs and MSNs + BMP-2 subgroups regarding new hard tissue formation in both groups and apical closure in group I (P > 0.05).ConclusionMSNs with/without BMP-2 scaffolds enabled the continuing growth of roots in immature teeth with necrotic pulps and periapical pathosis. Addition of BMP-2 to MSNs scaffold improved its outcome in regenerative endodontics.Clinical relevanceMSNs with/without BMP-2 scaffolds may alternate blood clot for regenerative endodontic treatment of immature teeth with necrotic pulps.

Regenerative endodontic treatment and traumatic dental injuries.

Pulp necrosis is the most common complication following dental trauma and is often associated with apical periodontitis. The management of these teeth is challenging in terms of large root canals, open apices, thin dentinal walls, and short roots. Over decades the conventional treatment for these teeth was calcium hydroxide apexification, a time-consuming procedure despite high success rates. Subsequently after the introduction of mineral trioxide aggregate and hydraulic calcium silicate materials single visit apical plug procedures became increasingly practiced with comparable success rates to the conventional apexification. The search continued afterward for a clinical procedure that may stimulate further root development and apical closure to avoid the long-term complication of root fracture after apexification. Regenerative procedures using stem cells derived from the apical papilla and blood clots as scaffolds were then introduced for the management of immature teeth, with variable protocols and success rates. This review will cover the evidence available and current position of regenerative endodontic procedures in traumatized immature teeth with apical periodontitis, in terms of clinical protocols, outcome, and potential prognostic factors.

Radiographic Evaluation of Regenerative Endodontic Procedures and Apexification Treatments with the Assessment of External Root Resorption

IntroductionThis multicentered cohort study evaluated the radiographic outcomes of regenerative endodontic procedures (REPs) and apexification treatments (APEX) of immature teeth with endodontic disease. Materials and MethodsThis cohort study included a retrospective record review and prospective data collection of pediatric patients with teeth treated with REPs or APEX between 2005 and 2014. Data including the presence of a periapical lesion, external root resorption, obliteration, apical hard tissue, apical closure, intracanal calcifications, and radiographic root area (RRA) change based on measurements were collected/measured from radiographic images. Univariate and multivariate analyses were conducted. ResultsThe cohort included 190 subjects (204 teeth (92 REPs; 112 APEX)). The frequency of pretreatment periapical pathology was similar between cases in which the clinical treatment failed versus successful treatment cases. However, the frequency of pretreatment external root resorption was higher in failed cases than in successful cases (P = .007). The mean RRA change was greater than twenty percent in 21% of the REPs cases. In traumatized teeth, REPs resulted in less hard tissue formation than other endodontic disease etiologies measured by RRA (P = .001). Fifty-three percent of cases with ERR (16/30) showed signs of healing/arrest and were mostly treated with REPs (11/16). ConclusionsThe presence of ERR negatively affected the treatment outcome. There was significant variability in RRA change in REPs. Signs of healing/arrest of the resorptive lesion were radiographically visible in many cases treated with REPs.

Histologic Assessment of a Fast-Set Mineral Trioxide Aggregate (MTA) and Two Novel Antibacterial-Enhanced Fast-Set MTAs for Apexification and Periapical Healing of Teeth With Incomplete Root Formation in a Rat Model: An In Vivo Animal Study.

Background Pulp necrosis in incomplete root formation halts dentine development, resulting in larger canals with fragile walls and an open apex, complicating canal instrumentation and apical stop formation. Bioactive endodontic cements such as mineral trioxide aggregate (MTA) are crucial for creating artificial apical barriers or inducing apical foramen closure, but challenges remain regarding their antimicrobial efficacy and cytotoxicity. Modifications to MTA formulations aim to address these concerns. Methods This in vivo animal study involved 80 Wistar albino rats, with incomplete root formation induced by pulp exposure. Rats were divided into four groups receiving different MTA formulations for apexification: conventional MTA, modified MTA, and MTA enhanced with metronidazole or doxycycline. Histopathological evaluations were conducted at seven and 28 days post-treatment to assess calcific barrier formation, inflammatory reactions, and antimicrobial efficacy. Results By day 7, modified MTA formulations exhibited enhanced antibacterial activity compared to conventional MTA(p = 0.000), with fewer inflammatory reactions and microorganisms. By day 28, modified formulations showed superior calcific barrier formation, particularly in the metronidazole-and doxycycline-enhanced groups compared to conventional MTA (p = 0.000). These outcomes suggest that modifications to MTA formulations improve antimicrobial efficacy and calcific barrier formation in vivo. Conclusion Novel modified MTA formulations, particularly those enhanced with metronidazole or doxycycline, exhibit superior antibacterial efficacy and calcific barrier formation compared to conventional MTA. Further long-term studies are warranted to validate these findings for potential clinical translation.

Peptide KN-17-Loaded Supramolecular Hydrogel Induces the Regeneration of the Pulp-Dentin Complex.

Regenerating the pulp-dentin complex remains a decisive factor during apexification for immature permanent teeth. Peptide KN-17, which was modified based on the structure of cecropin B, could effectively interfere with bacterial growth and induce the migration of human bone marrow stromal cells (hBMSCs). This study aimed to investigate the effect of KN-17 on the tissue regeneration. To our surprise, KN-17 can significantly stimulate angiogenesis in vitro and in vivo, which may provide a guarantee for apical closure. Herein, a novel peptide/KN-17 coassembled hydrogel is developed via a heating-cooling process. Npx-FFEY/KN-17 supramolecular hydrogel can induce vessel development, stimulate odontogenic differentiation of human dental pulp stem cells (hDPSCs), and exert an antibacterial effect on Enterococcus faecalis (E. faecalis). Furthermore, coronal pulp excised rat molars are supplied with KN-17 or KN-17-loaded hydrogel and transplanted subcutaneously in BALB/c-nu mice. After 4 weeks, the hydrogel Npx-FFEY/KN-17 stimulates the formation of multiple odontoblast-like cells and dentin-like structures. Our findings demonstrate that the KN-17-loaded hydrogel can promote the regeneration of the pulp-dentin complex for continued root development.

Investigation of root apical closure of first permanent molars with cone-beam computed tomography: A retrospective study

Background/purposeThe objective of this study was to assess the root apical closure ages of first permanent molars retrospectively among a group of western Turkish children aged between 5 and 15 years using cone-beam computed tomography (CBCT). Materials and methodsCBCT images of 202 patients were examined. The patients were divided into 7 groups according to age: ≤8 years, 8–8.99 years, 9–9.99 years, 10–10.99 years, 11–11.99 years, 12–12.99 years, and ≥13 years. Teeth with at least one open apex were considered as ‘teeth with open apex’ and teeth with all closed apices were considered as ‘teeth with closed apex’. The data was evaluated by Pearson Chi-square test and Fisher's exact test. P value of <0.05 was considered statistically significant. ResultsApical closure rate of the maxillary first molars was 4.1%, 32.2%, 55.4%, 76.2%, and 90.6% at 8–8.99 years, 9–9.99 years, 10–10.99 years, 11–11.99 years, and 12–12.99 years, respectively. Apical closure rate of the mandibular first molars was 4.4%, 41.2%, 70.7%, 80.0%, and 92.2% at 8–8.99 years, 9–9.99 years, 10–10.99 years, 11–11.99 years, and 12–12.99 years, respectively. At 12–12.99 years, females had a significantly higher rate of closed root apices of mandibular first molars than males (P < 0.05). At 9–9.99 and 12–12.99 years, females had a significantly higher rate of closed root apices of maxillary molars than males (P < 0.05). ConclusionCBCT is a useful tool for the evaluation of root development. The results of present study can provide valuable aids for clinicians during root canal treatment of permanent first molars.

Use of Endodontic Procedures in Young Permanent Teeth.

Regenerative endodontic procedures (REPs) have emerged as a promising treatment option for young permanent teeth with pulp necrosis, offering the potential for tissue repair and preservation. A retrospective analysis was conducted on a cohort of 30 patients aged 8 to 16 years with pulp necrosis in young permanent teeth. The patients underwent REPs, including disinfection, triple antibiotic paste application, and a coronal barrier. Clinical and radiographic data were collected at baseline and follow-up appointments at 6, 12, and 24 months. Radiographs were analyzed for root lengthening, apical closure, and resolution of periapical lesions. The mean increase in root length after 24 months was 3.42 mm (SD ± 1.12 mm), and 90% of cases demonstrated complete apical closure. The overall success rate, defined as the absence of clinical symptoms and radiographic evidence of pathology, was 80. REPs show promising outcomes in young permanent teeth with pulp necrosis, promoting root development, and apical closure.

Management Strategies for Immature Teeth with Pulp Necrosis: An Umbrella Review of Systematic Reviews.

This review evaluates the effectiveness of treatment modalities for immature teeth with pulp necrosis, focusing on calcium hydroxide (CH) and mineral trioxide aggregate (MTA) apexification, as well as regenerative endodontic treatments (RETs). Recent advancements and clinical outcomes are highlighted. A comprehensive search of MEDLINE (PubMed), Embase, Cochrane Library, Scopus, and grey literature was conducted from inception to July 2024. Systematic reviews and meta-analyses (SR/MAs) assessing apexification and RET outcomes in immature teeth with pulp necrosis were included. Studies were selected based on predefined criteria, and data on study design, interventions, and outcomes were extracted. Methodological quality was evaluated using the AMSTAR-2 tool. 31 SR/MAs were included. The quality ranged from critically low to low, except one rated as high. MTA apexification was more effective than CH for faster apical barrier formation, though overall success rates were similar. MTA is preferred for its efficiency, but standardized protocols are needed, and tooth discoloration was noted as a potential complication. RET generally outperforms apexification in root maturation, with platelet concentrates like platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) showing promising results; PRP was associated with greater root length, while PRF showed superior apical healing. Variability in RET outcomes was noted due to the lack of standardized protocols. Comparative studies of RET versus apexification showed no significant differences in survival or overall success rates. RET often provides better apical closure and root development, though results vary. Both approaches are viable, but more research with standardized protocols and larger samples is needed to establish definitive clinical advantages. MTA apexification and RET are viable alternatives to CH apexification, with RET showing greater potential for root development and apical healing. Future research should focus on developing standardized protocols and uniform RET guidelines, and evaluating long-term outcomes to establish efficacy and safety.

Advancements and challenges in stem/progenitor cell transplantation for dentin-pulp regeneration: a systematic review of animal studies (part I).

Dentin-pulp regeneration through stem/progenitor cell transplantation represents a promising frontier in regenerative endodontics. This systematic review meticulously evaluates animal studies to investigate the efficacy of stem cell therapy in repairing/regenerating the dentine-pulp complex in mature/immature animal teeth. Employing a comprehensive electronic search of PubMed and Scopus databases up to October 2023, relevant English studies were identified/assessed. Evaluation parameters encompassed radiographic and histological assessments of dentin-pulp complex formation. Outcome measures included pulp-like and dentin-like tissues regeneration, apical healing, dentin thickening, apical closure, and dentinal bridge formation. The risk-of-bias assessment adhered to the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) guidelines. Out of 3250 identified articles, 23 animal experiments were included, categorized into regenerative procedures in mature teeth (n=11), regenerative procedures in immature teeth (n=4), and vital pulp therapy (n=8). Despite the promising potential, the bias in the included studies was high. Notably, Various scaffolds, and growth factors were employed, highlighting the heterogeneity across the studies. Dental pulp stem cells (DPSCs) and bone marrow stem cells, especially specific subfractions, demonstrated notable regenerative potential: hypoxic conditions and extracellular vesicles from preconditioned DPSCs enhanced regeneration, with considerations of cell fate. Donor age impacted regeneration, and challenges persisted in pulpotomy and direct pulp capping. Scaffold and growth factor choices influenced outcomes, underscoring the need for standardized strategies. Despite the promise, clinical viability faces hurdles, necessitating further investigation into adverse effects, optimized scaffolds, and regulatory considerations. This systematic review illuminates the potential of stem cell transplantation for dentin-pulp complex regeneration. The overall evidence quality, influenced by study heterogeneity and biases, underscores the need for cautious interpretation of findings. Future studies should refine methodologies and establish reliable histological parameters for meaningful advancements in dentin-pulp regeneration.

Comparison between Calcium Hydroxide with Mineral Trioxide Aggregate and Regenerative Endodontics in Inducing Root Apex Closure during Apexification – A Systematic Review and Meta-analysis

Abstract This study aimed to assess better effectiveness between regenerative endodontic procedures (REP) and apexification procedures (AP) with mineral trioxide aggregate (MTA) and calcium hydroxide for inducing root end apex closure. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed and registered in PROSPERO-CRD42023398997. Electronic databases were searched for studies evaluating effectiveness of REP and AP in terms of survival rate, success rate, increase in root length, root width and decrease in apical diameter. Cochrane risk of bias (RoB) -2 tool was used for quality assesssment using RevMan 5.3. The risk ratio (RR) and standardized mean difference (SMD) was used as summary statistic measure with random effect model (P &lt; 0.05). Nine studies were included in qualitative synthesis and eight studies for meta-analysis. Quality assessment revealed moderate to low risk of bias. The pooled estimate through RR and SMD favoured REP being superior to AP for better survival rate (RR = 1.01 (0.96 – 1.06)), success rate (RR = 1.09 (0.96 – 1.24)), increase in root length (SMD = 0.25 (-0.14 – 0.63)), root width (0.66 (0.22 – 1.10)) and decrease in apical diameter (SMD =0.66 (-0.51 – 1.83)). Funnel plot did not show any heterogeneity indicating absence of publication bias. REP significantly improved apical root end closure. AP are equally effective in forming calcific barrier, however it was concluded that regeneration procedures are comparably superior to apexification procedures with greater outcomes. Clinicians should consider employing the REP in cases when root development is severely deficient and where tooth’s prognosis is hopeless even with an apexification procedure.

Stapler size independently predicts postoperative complications following stapled ileocolic anastomosis: Aretrospective cohort study.

Staplers used in ileocolic anastomosis construction differ in length and height. We assessed the impact of stapler type in creating ileocolic anastomoses on postoperative outcomes. This retrospective cohort study of an Institutional Review Board approved database included patients who underwent laparoscopic right colectomy for cancer between January 2011 and August 2021. All patients had construction of extracorporeal antiperistaltic stapled ileocolic anastomosis using a linear cutting stapler. Main outcome measures were short-term (<30 day) morbidity and mortality. In all, 270 patients (136 men; median age 70.2 years) were included. A 75 mm stapler was used in 49 (18.1%) patients, 80 mm in 97 (35.9%) and 100 mm in 124 (45.9%). Blue cartridge (stapler height 3.5 mm) was used in 175 (64.5%) and green cartridge (4.8 mm) in 18 (7%) patients; this information was unavailable in 77 (28.5%) cases. Apical enterotomy closure was performed by linear stapler in 54% and linear cutting stapler in 46%. Apical staple line reinforcement or imbrication suturing was used in 26.3%. The overall postoperative complication rate was 28.9%. The anastomotic leak rate was 2.6%. Independent predictors of complications after laparoscopic right colectomy were older age (OR 1.03, 95%CI 1-1.06; P = 0.01), extended colectomy (OR 2.76, 95%CI 1.07-7.08; P = 0.035) and emergency surgery (OR 4.5, 95%CI 1.3-14.9; P = 0.014). A 100-mm linear cutting stapler was an independent protective factor against postoperative complications (OR 0.3, 95%CI 0.18-0.85; P = 0.019). Stapler height and closure technique of apical enterotomy did not affect postoperative complications. Independent predictors of complications after laparoscopic right colectomy were older age, extended colectomy and emergency surgery. Using a 100 mm stapler was an independent protective factor against postoperative complications.

Cell-Based Regenerative Endodontics for the Treatment of Irreversible Pulpitis: AnIn VivoInvestigation

IntroductionThis study aims to investigate the ability of umbilical cord mesenchymal stem cells (UC-MSC) to enhance the regeneration of pulp-dentin complex in immature permanent teeth with irreversible pulpitis. MethodsA total of 32 mandibular premolar teeth with immature apices in 5 dogs were used in this in-vivo randomized controlled trial (RCT). Eight healthy teeth without pre-existing pathosis served as the positive control samples and received no treatment, while in another 8 teeth, the pulp was completely extirpated (negative control). Class V cavities were prepared to induce inflammation in the remaining 16 teeth (groups 3 and 4) and the pulp was extirpated 2-4 mm short of the radiographic apex. Of the 16, the 8 teeth in group 4 received 1 mL of cord blood stem cells with a hydrogel scaffold. Blood clots were covered with mineral trioxide aggregates at the cementoenamel junction in the experimental groups, and teeth were filled with RMGI and composite. Three months later, block sections were removed for histologic evaluations for the evaluation of postoperative apical closure, degree of inflammation, and presence of normal pulp tissue. The data were statistically analyzed with the chi-square test (P < .05). ResultsAll teeth with complete pulp extirpation demonstrated pulpal necrosis with no postoperative closure of their apices, while apical closure was seen in all the teeth in the remaining groups. There was a statistically significant (P < .001) difference in the presence of inflammation and normal pulp tissue between the experimental groups. The teeth in group 3 showed normal pulp tissue extending to the level of MTA, but there was inflammation within the canal space. In contrast, the teeth in the UC-MSC group demonstrated organized, normal pulp tissue with no inflammation. ConclusionBased on these results, the regeneration of the pulp-dentin complex is possible with no inflammation when UC-MSCs are used and 2-4 mm of the apical pulp remains intact in immature teeth with irreversible pulpitis.

Age of Dental Apical Closure in Domestic Cats.

Data on the age of apical closure in felines is limited. Moreover, differences in age of apical closure between male and female cats have not been studied. The aim of this study was to determine the timing of apical closure in cats and determine if sex or position in the dental arch affected closure. In this retrospective descriptive study, intraoral radiographs were obtained at monthly or multiple-monthly intervals for 18 cats. Nine were intact females and 9 were neutered males, ranging from 6 to 9.4 months of age at the start of the study which ranged over an 8-month period. Radiographs were evaluated to establish age of apical closure for all canine teeth as well as the mandibular premolar and molar teeth. Mandibular canine tooth apices closed between 10 and 12 months of age and maxillary canine tooth apices closed between 12 and 14 months of age. The mesial and distal root apices of both the mandibular third and fourth premolar teeth closed between 8 and 9 months. The mandibular first molar tooth mesial and distal root apices closed between 8 and 8.5 months. Root apices of canine teeth closed earlier in female cats than in male cats with mandibular canine tooth root apices closing significantly earlier than maxillary canine tooth roots in both sexes. These findings suggest that there are notable differences in age of apical closure between male and female cats and discernible trends in timing of apical closure among teeth in the dental arcade.

Combination of metformin and double antibiotic paste for the regeneration of non-vital immature teeth: a preliminary randomized clinical study

BackgroundThe present study aimed to investigate whether incorporating metformin in double antibiotic paste (DAP) can promote the regeneration process of non-vital immature teeth.MethodsOut of 32 pediatric patients undergoing regenerative endodontic procedures (REPs), 6 cases with a follow-up period of less than 12 months or lack of documentation were excluded then the remaining 26 were analyzed. 15 cases received DAP, and 11 cases received a DAP + metformin as the intra-canal medicament, kept for an average of 23 days. During 18 months of follow-up, clinical and radiographic examinations were performed to evaluate the treatment outcomes based on the resolution of apical periodontitis, root development, and the occurrence of intracanal calcification. The chi-square test was used for the statistical analysis (P < 0.05).ResultsAll patients demonstrated resolution of apical periodontitis; however, complete apical closure was only seen in 50% of the patients. The rate of apical closure and root length was significantly higher in the DAP + metformin group (P = 0.047), although the two groups were not significantly different in terms of root width (P = 0.184). Canal obliteration was seen in 15% of cases, all of which were in the DAP group.ConclusionsAccording to the present findings, metformin could promote root development in the regeneration process when incorporated in DAP.Trial registrationThis clinical trial was registered on the Iranian Registry of Clinical Trials (IRCT20200120046197N1) on 26.2.2021.

Management and outcomes of apexification procedures in traumatized immature teeth

The oral health of pediatric patients is a significant concern, with dental injuries being a common occurrence in this vulnerable population. Traumatic injuries to immature teeth, characterized by incomplete root development and open apices, present unique challenges that require specialized clinical management. Understanding the anatomy and developmental characteristics of immature teeth is crucial for effective management. Historically, apexification procedures relied on calcium hydroxide, but advancements in dental pulp biology led to regenerative endodontics, a transformative approach that preserves pulp vitality while promoting apical closure. Contemporary techniques include calcium hydroxide apexification, mineral trioxide aggregate (MTA) apexification, and regenerative endodontics, each with its advantages and considerations. Patient selection, radiographic assessment, choice of biocompatible materials, and post-operative care are key components of contemporary apexification protocols. Advanced imaging modalities like cone-beam computed tomography (CBCT) enhance diagnostic accuracy. Challenges in apexification procedures include infection control, the risk of root fractures, and dealing with resorption phenomena. Moreover, pediatric patients require special attention to address compliance and psychological factors. The long-term outcomes of apexification procedures extend beyond clinical and radiographic parameters and encompass growth and development as well as the quality of life of pediatric patients. Preservation of arch integrity, prevention of malocclusion, and maintaining oral health-related quality of life are vital considerations.

Regenerative endodontics: vary of scaffolds and its benefits for pediatric dentistry

Background. Regenerative Endodontic Procedures deliver a suitable environment to promote natural regeneration/repair with a functional pulp–dentin wall and apical closure. However, REPs have a number of features that can complicate their implementation, especially for children. One of them is scaffold formation.&#x0D; Objective. To describe alternative scaffold formation options for pulp revitalization and compare their effectiveness and describe possible causes of periapical tissues not bleeding during endodontic regenerative procedures.&#x0D; Materials and methods. A comprehensive search strategy was done through PubMed and Cochrane Library databases by using MESH terms equivalent to the keywords. Review articles for the last 5 years were selected according to the keywords with exclusion criteria. &#x0D; Results. According to the search criteria and keywords, 801 articles were obtained, after applying the exclusion criteria, 11 ones that met the selection requirements were left.&#x0D; Conclusions. The main method of scaffold obtaining is the blood clot formation. However, if it is not possible to make the periapical tissues bleed for clot formation, then the use of platelet-enriched autologous plasma or platelet-rich fibrin is recommended. This technique has proven to be as effective as the main one. It can prevent painfulness caused by bleeding provoking for blood clot formation.