Discoloration after revascularization using calcium phosphosilicate-based bioceramic versus mineral trioxide aggregate in necrotic immature permanent anterior teeth: A Randomized clinical trial.

Aim: The aim of the current study is to evaluate the effect of calcium phophosilicate-based bioceramic "Totalfill bioceramic putty" and white mineral trioxide aggregate (WMTA) as the coronal plug on discoloration after revascularization of necrotic immature permanent anterior teeth. Materials and Methods: This study was conducted on (48) necrotic young permanent central incisors in children ranging from 8 to 14 years old, that were randomly allocated to either Totalfill bioceramic (Group I = 24) or WMTA (Group II = 24) as the coronal plug. Two visits revascularization protocol was adopted in this study using 1.5% sodium hypochlorite, followed by 17% ethylenediaminetetraacetic acid, and ending with a saline flush as irrigation solution. The double antibiotic paste was used as intracanal medication. The blood clot was used as scaffold followed by the application of collagen membrane followed by coronal plud malterial. Finally, the access was sealed using resin composite restoration and composite restoration. Clinical assessment was conducted at 1, 3, 6, 9, and 12 months, while radiographic assessment was conducted at 6 and 12 months. Data were statistically analyzed using the Chi-squared test for intergroup comparisons and Cochran's Q test for intragroup comparison. Results: Clinically, Group I exhibited a success rate of 100%, whereas Group II exhibited a success rate of 85.7%. Radiographically, both materials showed a 90.5% success rate. There was no statistically significant difference between both materials for all assessed clinical and radiographic parameters at different follow-up periods. Conclusions: Both Totalfill bioceramic putty and WMTA can be used successfully as coronal plug in esthetic areas.

Treatment outcomes of regenerative endodontic therapy in immature permanent teeth with pulpal necrosis: A systematic review and network meta-analysis.

AIM: The aim of this study was to assess which treatment modality regarding scaffold selection for immature permanent teeth with pulpal necrosis will be the most successful for regenerative endodontic treatment (RET). METHODOLOGY: PubMed, Cochrane, Web of Science and Embase, and additional records until August 2022 were searched providing a total of 3021 articles, and nine of these articles were included for quantitative synthesis. The reviewers selected eligible randomized controlled trials and extracted pertinent data. Network meta-analysis was conducted to estimate treatment effects for primary outcomes (clinical and radiographic healing) and secondary outcomes (apical closure, root length and root wall thickness increase) following RET [mean difference (MD); 95% credible interval (CrI) and surface under the cumulative ranking curve (SUCRA)]. The quality of the included studies was appraised by the revised Cochrane risk of bias tool, and the quality of evidence was assessed using the GRADE approach. RESULTS: Six interventions from nine included studies were identified: blood clot scaffold (BC), blood clot scaffold with basic fibroblast growth factor, blood clot scaffold with collagen, platelet pellet, platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). The PRP scaffold showed the greatest increase in root lengthening at 6-12 months (MD = 4.2; 95% CrI, 1.2 to 6.8; SUCRA = 89.0%, very low confidence). PRP or PRF achieved the highest level of success for primary and secondary outcomes at 1-6 and 6-12 months. Blood clot scaffold (with collagen or combined with basic fibroblast growth factor (bFGF)) achieved the highest level of success for secondary outcomes beyond 12 months follow-up. A very low to low quality of evidence suggests that both PRP and PRF exhibit the greatest success evaluating primary and secondary outcomes within 12 months postoperatively compared to the traditional blood clot scaffold protocol. CONCLUSION: Limited evidence suggests both PRP and PRF exhibit success in the short-term, not long-term. The value of this information stems in its recommendation for future randomized trials prioritizing both of these materials in their protocol.

The applications of the plasma matrix in the treatments of dental pulp and periapical diseases / 口腔疾病防治

@#The plasma matrix is a kind of autologous blood conduct. It has been widely used in maxillofacial tissue regeneration, skin cosmetology and some other fields. Recently, to preserve the dental pulp as well as the teeth, pulp regeneration therapy and apical surgery have become increasingly important as well as the applications of bioactive materials. As a kind of autologous bioactive material, the plasma matrix has some natural advantages as it is easy to obtain and malleable. The plasma matrix can be used in the following cases: ①pulp revascularization of young permanent teeth with open apical foramina that cannot stimulate apical bleeding; ② apical barrier surgery with bone defects and large area perforation repair with bone defects or root sidewall repair surgery; ③ apical surgeries of teeth with large area of apical lesions, with or without periodontal diseases. The plasma matrix is a product derived from our blood, and there are no obvious contraindications for its use. Several systematic reviews have shown that the plasma matrix can effectively promote the regenerative repair of dental pulp in patients with periapical diseases. However, the applications of plasma matrix are different because its characteristics are affected by different preparation methods. In addition, there is still a lack of long-term clinical researches on the plasma matrix, and the histological evidences are difficult to obtain, so a large number of in vitro and in vivo experimental studies are still needed. This article will describe the applications of different kinds of plasma matrix for dental pulp regeneration and bone tissue regeneration in apical surgeries to provide references for clinicians in indication selection and prognosis evaluation.

Evaluation of removal efficiency of capping materials used in pulp revascularization in vitro.

BACKGROUND: This study aimed to evaluate the removal efficiency of different capping materials used in pulp revascularization (PR) in a failure scenario. METHODS: The apices of freshly extracted 30 maxillary incisors were cut to mimic the immature teeth; then, root canals were shaped up to #6 Peeso reamers. The regeneration steps of the American Association of Endodontists (AAE) were followed to simulate PR treatment in vitro. The canals were dressed with the Ciprofloxacin and Metronidazole medicament mixture for 2 weeks. Then capping material groups were created: BioDentine (BD), ProRootMTA (PMTA), and RetroMTA (RMTA) (n = 10). The sealed specimens were stored for 2 weeks at 37 ºC in phosphate-buffered saline then the samples were examined by micro-computed tomography (µ-CT) analysis. Set capping materials were retrieved using a specific cement removal kit by a single blind operator. The residue materials were examined again by µCT. Kruskal-Wallis and Mann-Whitney U tests sought the significance for residue volumes. One-way ANOVA and Tukey post hoc tests with the Bonferroni corrections sought significance for the duration (p = 0.05). RESULTS: In the first examined µCT data, the mean (SD) capping material volumes of the PMTA, BD, and RMTA were 6.447 µm3 (1.086), 8.771 µm3 (0.491), and 8.114 µm3 (2.447), respectively. In the last examined µCT data, the median (IQR) residual volumes of the PMTA, BD, and RMTA were 0.051 µm3 (0.1), 0.313 µm3 (0.5), and 0.124 µm3 (0.1), respectively. A significant difference was found between BD and PMTA in the residual volumes (p < 0.05). The mean (SD) durations of the retrieving procedures of PMTA, BD, and RMTA were 19.83 min (2.34), 19.24 (3.60), and 22.04 (1.68), respectively (p = 0.063). CONCLUSIONS: Within the limitations of the presented study, it was concluded that the capping materials were largely removed from the root canals using a non-invasive approach. Nevertheless, this duration of the retrieving could be described as long.

Different endodontic treatments induced root development of two nonvital immature teeth in the same patient: A case report.

BACKGROUND: Pulp revascularization is a novel way to treat immature teeth with periapical disease, and the technique has become increasingly well established in recent years. By puncturing the periapical tissue, bleeding is induced, and a blood clot is formed in the root canal. The blood clot acts as a natural bioscaffold onto which mesenchymal stem cells from periapical tissue can be seeded and restore pulp vascularity, thus promoting root development as well as apical closure. Although the effect of pulp revascularization is ideal, there are certain requirements for the apical condition of the teeth. The apical barrier technique and apexification are still indispensable for teeth that cannot achieve ideal blood clot formation. In addition, a meta-analysis of several clinical studies concluded that pulp revascularization has no significant advantages over other treatments. CASE SUMMARY: A 10-year-old girl complained of pain in the right upper and lower posterior teeth for 2 d. Clinical and radiological examinations revealed that both the right maxillary and mandibular second premolars were immature with periapical radiolucency. The right maxillary second premolar was treated by pulp revascularization, while the right mandibular second premolar was treated by conventional apical barrier surgery after revascularization failed. The purpose of this report is to compare the different root maturation processes induced by the pulp revascularization and apical barrier techniques in the same patient in homonymous teeth from different jaws. Twelve months of follow-up showed that the apical foramen of both teeth presented a clear tendency to close; however, the tooth treated with pulp revascularization showed a significant increase in root length as well as root canal wall thickness. CONCLUSION: For the treatment of nonvital immature teeth, pulp revascularization showed a superior therapeutic effect in comparison with the apical barrier technique.

Pulp Revascularization After Autotransplantation of the Mandibular Canines With Partially Resected Roots: Report of 5 Cases With Follow-ups Between 26 and 80 Months.

INTRODUCTION: Transmigrated (migrated through the midline) mandibular canines constitute a treatment challenge. Advanced transmigration can be successfully treated by autotransplantation. In developing canines, pulp revascularization is typical after transplantation. On the contrary, the pulp of teeth with completed apex formation does not undergo revascularization. In this case, root canal treatment becomes compulsory and decreases the success of autotransplantation. The aim of this observational retrospective study was to evaluate whether partial resection of the root (performed during the autotransplantation of mature canines) would enable revascularization of the pulp after the surgery. METHODS: Five transmigrated mandibular canines with complete apex formation before the surgery were evaluated. During the autotransplantation surgery, the resection of 2 to 4 mm of the root apex was performed to open the path for revascularization of the pulp after surgery. The transplanted teeth were observed during healing after the surgery for the presence of pulp obliteration. Clinical and radiographic examinations were performed. RESULTS: All treated canines survived the minimum observation period of 2 years (ranging from 26 to 80 months, mean: 55 months) without pulp healing complications. The survival was 100%, and the success was 80%. In one canine, the external cervical root resorption was diagnosed and treated 1 year after the surgery. At the final examination, transplanted canines presented radiographic features of pulp obliteration, normal mobility, and healthy periodontal tissues. CONCLUSIONS: The surgical protocol proved to be successful in promoting revascularization to maintain pulp vitality, in all cases. The outcomes confirm that autotransplantation, combined with the resection of the root, constitutes a valid treatment for mature ectopic canines.

Pulp revascularization on an adult mandibular right second premolar: A case report.

BACKGROUND: Pulp revascularization has become a new method for the treatment of periapical diseases in young permanent teeth in recent years. Through root canal flushing and disinfection, avoiding mechanical preparation, guiding apical stem cells into the root canal and promoting the continuous development of tooth roots, it has achieved good clinical curative effects. But in adult patients with chronic periapical periodontitis with immature roots and open apices, apical barrier technology is often used to treat these teeth. CASE SUMMARY: Pulp revascularization of a 26-year-old patient's tooth was performed using cefaclor instead of minocycline and iRoot BP instead of mineral trioxide aggregate as intracanal medication. The case was followed up for 36 mo. Observations showed evidence of regression of clinical signs and symptoms, resolution of apical periodontitis and no discolouration of affected teeth. CONCLUSION: For adult patients with chronic periapical periodontitis with immature roots and open apices, pulp revascularisation showed favourable results in treating these teeth.

Efficacy of Ciprofloxacin, Metronidazole and Minocycline in Ordered Mesoporous Silica against Enterococcus faecalis for Dental Pulp Revascularization: An In-Vitro Study.

Pulp revascularization of teeth with necrotic pulp has become an alternative treatment in cases with immature apex. Microbial control is essential to achieve a successful outcome and continued root development. Enterococcus faecalis (E. faecalis) is the most frequently isolated bacterial species in root canals of endodontically failed teeth. Our main goal was to compare the in-vitro antimicrobial efficacy of different antibiotic formulations delivered by ordered mesoporous silica (OMS) against E. faecalis. To determine antibiotic susceptibility, we tested OMS and triple antibiotic paste (TAP; ciprofloxacin:metronidazole:minocycline) with different reagents in different concentrations, using the Kirby−Bauer disk diffusion method. OMS and metronidazole showed no antibacterial activity against E. faecalis. Mixtures of OMS and antibiotics in proportions of 2:2:14 and 4:1:7 (mg/L of ciprofloxacin:metronidazole:minocycline, respectively) showed the lowest antibacterial activity. The antibacterial activity of the combined solutions of ciprofloxacin and metronidazole was significantly higher (p < 0.005). Combinations in different concentrations of minocycline, ciprofloxacin, and metronidazole in OMS have shown activity against E. faecalis, although the combined use of ciprofloxacin and metronidazole has shown the most effective results. This study demonstrates the efficacy of intracanal antibiotic combination paste activity against E. faecalis, avoiding the use of minocycline, whose undesirable effect of teeth staining is a common problem for patients and professionals in dental clinic.

Management of internal inflammatory root resorption using injectable platelet-rich fibrin revascularization technique: a clinical study with cone-beam computed tomography evaluation.

OBJECTIVES: The current study evaluated clinically and radiographically the management of internal inflammatory root resorption (IIRR) in permanent anterior teeth with or without periapical lesions using injectable platelet-rich fibrin (i-PRF) regenerative approach. METHODS: Ten systemically healthy patients, with thirteen anterior mature teeth diagnosed with IIRR were selected for the study. At the first visit, the tooth was anesthetized, access cavity opened, root canals were mechanically prepared then medicated with calcium hydroxide and temporarily sealed. After 2-4 weeks, regenerative endodontic procedures were performed by preparing and applying i-PRF inside the canal, then a freshly prepared PRF membrane was placed over it. White mineral trioxide aggregate was placed over the PRF matrix, and the tooth was restored with a glass ionomer cement base and resin composite restoration. The patients were recalled for clinical and radiographic evaluation and follow-up every 3 months for 12 months. Cone-beam computed tomography (CBCT) imaging was performed preoperatively and after 12 months. RESULTS: Clinical evaluation results showed resolution of signs and symptoms through the follow-up period in all of the cases. Both CBCT imaging readings of IIRR lesions and periapical lesions revealed a volumetric significant difference (p = 0.00) between the preoperative and the 12-month follow-up period. CONCLUSIONS: Usage of i-PRF could arrest and allow for healing of IIRR in permanent mature teeth and allow for periapical healing with successful clinical results. CLINICAL RELEVANCE: i-PRF revascularization technique proved to be a successful REP in the treatment of the IIRR, reducing the number of appointments and increasing patient compliance.

Aplicación de Biodentine en Endodoncia Regenerativa: Presentación de Tres Casos Clínicos / Application of Biodentine in Regenerative Endodontics: Presentation of Three Clinical Cases

El Biodentine es un material biocerámico y bioacti-vo que puede emplearse como sustituto activo de la dentina. Entre sus numerosos usos se incorpora su utilización como sellador del coágulo en los procedi-mientos endodónticos regenerativos, logrando me-jores propiedades con respecto al Gold standard. Se presenta la resolución clínica y radiográfica de tres situaciones clínicas, mediante la aplicación del proto-colo de los procedimientos endodónticos regenerati-vos, en los que se utilizó Biodentine como alternativa para el sellado del coágulo a nivel cérvico-radicular, en la obturación a nivel del límite amelocementario (AU)

Biodentine is a bio-ceramic and bioactive material that can be used as an active substitute for dentin. Its many uses include its use as a clot sealer in regenerative endodontic procedures, achieving better properties compared to the Gold standard. The clinical and radiographic resolution of three clinical situations is presented, by applying the protocol of regenerative endodontic procedures, where Biodentine was used as an alternative for sealing the clot at the cervical-radicular level in the obturation at the level of the cementoenamel limit (AU)

Antimicrobial and immunomodulatory in vitro profile of double antibiotic paste.

AIM: To evaluate the antimicrobial and immunomodulatory activity of double antibiotic paste (DAP) in an in vitro infection model. METHODOLOGY: The minimum inhibitory and bactericidal concentrations (MIC and MBC) and the antibiofilm activities (TTC assay) of DAP and its components (ciprofloxacin and metronidazole) were evaluated against Staphylococcus aureus and Enterococcus faecalis compared with triple antibiotic paste (TAP). The cellular viability of RAW 264.7 macrophages (24 and 72 h) and L929 fibroblasts (48 and 72 h) was evaluated by MTT. Furthermore, the production of TNF-α, IL-12, IL-6, IL-1α, IL-10 and NO (on RAW 264.7), besides IL-6, TGF-ß and NO (on L929), stimulated with DAP in baseline and associated with heat-killed microbial-antigen conditions was measured by ELISA and Griess reaction. Data were analysed using the one-way ANOVA test with Bonferroni's corrections. RESULTS: The MBC of pharmacopoeia DAP was similar to TAP for E. faecalis (0.25 µg.  mL-1 ) and lower for S. aureus (DAP 1 µg. mL-1 and TAP 2 µg. mL-1 ; p < .001). Ciprofloxacin was the most effective antibiofilm drug from the pastes (35% of reduction for E. faecalis and S. aureus; p < .0001), and both pastes had a similar antibiofilm eradication against both biofilm species (29% and 35% for S. aureus and 76% and 85% for E. faecalis; p < .0001). DAP was cytotoxic against the tested cells. DAP significantly upregulated IL-1α (p < .001), IL-6 (p < .0001), TNF-α (p < .01) and IL-12 (p < .05; in the absence of antigens) and significantly reduced IL-6 (p < .0001; in the presence of HK-S. aureus) and IL-10 (p < .05; in the presence of both antigens) on macrophages. Furthermore, DAP upregulated IL-6 (p < .001) and NO (p < .05; in the absence of antigens), IL-6 (p < .001; in the presence of HK-S. aureus) and reduced NO (p < .001; in the presence of HK-S. aureus). CONCLUSIONS: Double antibiotic paste and TAP had similar antimicrobial activity against S. aureus and E. faecalis. DAP upregulated pro-inflammatory cytokines mainly in the absence of antigens and had pro- and anti-inflammatory activity in RAW 264.7 macrophages and L929 fibroblasts in the presence of antigens involved in pulp infections.

Angiogenic hydrogels for dental pulp revascularization.

Angiogenesis is critical for tissue healing and regeneration. Promoting angiogenesis in materials implanted within dental pulp after pulpectomy is a major clinical challenge in endodontics. We demonstrate the ability of acellular self-assembling peptide hydrogels to create extracellular matrix mimetic architectures that guide in vivo development of neovasculature and tissue deposition. The hydrogels possess facile injectability, as well as sequence-level functionalizability. We explore the therapeutic utility of an angiogenic hydrogel to regenerate vascularized pulp-like soft tissue in a large animal (canine) orthotopic model. The regenerated soft tissue recapitulates key features of native pulp, such as blood vessels, neural filaments, and an odontoblast-like layer next to dentinal tubules. Our study establishes angiogenic peptide hydrogels as potent scaffolds for promoting soft tissue regeneration in vivo. STATEMENT OF SIGNIFICANCE: A major challenge to endodontic tissue engineering is the lack of in situ angiogenesis within intracanal implants, especially after complete removal of the dental pulp. The lack of a robust vasculature in implants limit integration of matrices with the host tissue and regeneration of soft tissue. We demonstrate the development of an acellular material that promotes tissue revascularization in vivo without added growth factors, in a preclinical canine model of pulp-like soft-tissue regeneration. Such acellular biomaterials would facilitate pulp revascularization approaches in large animal models, and translation into human clinical trials.

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.

Host defense peptide IDR-1002 associated with ciprofloxacin as a new antimicrobial and immunomodulatory strategy for dental pulp revascularization therapy.

Regenerative therapies such as dental pulpal revascularization appear as an option for traumatized immature permanent teeth. However, the triple antibiotic paste - TAP (metronidazole, minocycline, and ciprofloxacin), used for these therapies, can generate cytotoxicity and dentin discoloration. In contrast, host defense peptides (HDPs) are promising antimicrobial and immunomodulatory biomolecules for dentistry. This study aimed to evaluate in vitro the antimicrobial activity (against Staphylococcus aureus and Enterococcus faecalis) and the immunomodulatory potential (by the evaluation of IL-1α, IL-6, IL-12, IL-10, TNF-α and NO, in RAW 264.7 macrophages and IL-6, TGF-ß and NO, in L929 fibroblast) of synthetic peptides (DJK-6, IDR-1018, and IDR-1002), compared to TAP in an in vitro infection model containing heat-killed antigens from E. faecalis and S. aureus. Furthermore, the synergistic potential of ciprofloxacin and IDR-1002 was evaluated by checkerboard. Ciprofloxacin was the best antimicrobial of TAP, besides acting in synergism with IDR-1002. TAP was pro-inflammatory (p < 0.05), while the association of ciprofloxacin and IDR-1002 presented an anti-inflammatory profile mainly in the presence of both heat-killed antigens (p < 0.05). Based on these results, ciprofloxacin associated with IDR-1002 may demonstrate an efficient antimicrobial and immunomodulatory action in this in vitro model. Further in vivo studies may determine the real potential of this combination.

Research on the color stability of Biodentine and MTA within the blood environment / 口腔疾病防治

Objective@#To compare the color stability of Biodentine and mineral trioxide aggregate (MTA) within the blood environment in vitro and to further investigate the underlying reasons for such color instability. @*Methods @#We first generated Biodentine and MTA discs with a diameter of 5 mm and a height of 3 mm. 24 discs of each material were randomly divided into two groups: the deionized water group and the defibrinated sheep blood group. Discs of each group were immersed for 1 day or 7 days before assessments. First, all discs were photographed to directly compare the discoloration of Biodentine and MTA. The color degree of the two materials was tested by a spectrophotometer. Then, the high-resolution morphological characteristics were observed by scanning electron microscopy. Finally, the chemical contents of each element in the material were measured by energy-dispersive spectroscopy.@*Results @#Compared to immediately after stripping, a change in the brightness of discs after immersion in defibrinated sheep blood for 1 day was observed only in MTA. On the 7th day after being immersed in blood, the colors of both the Biodentine and MTA discs darkened and turned deep red, but the darkness of the MTA discs increased significantly. The color change of MTA immersed in blood was measured on a spectrophotometer with a greater 7-day ∆E (21.257 ± 0.955) than the Biodentine 7-day ∆E (5.833 ± 0.501) (t=24.781, P < 0.001). MTA exhibits more discoloration as the immersion time goes on. A significant difference was noted between the 1-day ∆E(6.233 ± 0.888) and the 7-day ∆E(t=19.956, P < 0.001) of MTA immersed in blood. However, there was no statistically significant difference between the 1-day ∆E (6.790 ± 0.831) and the 7-day ∆E(t=1.707, P=0.163) of Biodentine immersed in blood. It was observed by scanning electron microscopy that after 7 days of immersion in the defibrinated sheep ablood, the surface porosity of MTA was larger than that of Biodentine, and the crystal edge of MTA became rounded and blunt. The analysis by energy-dispersive X-ray spectroscopy showed that the oxygen content decreased and the bismuth content increased in MTA after immersion in defibrinated sheep blood for 7 days. Zirconium was not detected in Biodentine due to its low radiodensity, but the contents of other elements were stable in Biodentine after immersion in defibrinated sheep blood for 7 days. @* Conclusion@#The color stability of Biodentine within the blood environment is better than that of MTA in vitro, which is mainly related to the low surface porosity and stable composition of the anti-radiation agent of Biodentine.

Quantitative Assessment of Root Development after Regenerative Endodontic Therapy: A Systematic Review and Meta-Analysis.

INTRODUCTION: The purposes of this review were to appraise the level of evidence of the existing regenerative endodontic therapy (RET) publications, perform a meta-analysis on the survival and healing rates of necrotic immature permanent teeth treated with RET, and run a meta-analysis on the quantitative assessment of the root development of those teeth. METHODS: Electronic searches were performed in Web of Science, PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane Library databases. Two authors independently screened the titles and abstracts for eligibility. The analyses were performed on the clinical outcomes (ie, survival, healing, and root development) of the procedure. RESULTS: Eleven articles were included in the qualitative and quantitative syntheses. Three studies were randomized controlled trials, 6 were prospective cohort studies, and 2 were retrospective cohort studies. The pooled survival and healing rates were 97.3% and 93.0%, respectively. The pooled rates of root lengthening, root thickening, and apical closure were 77.3%, 90.6%, and 79.1%, respectively. However, if 20% radiographic changes were used as a cutoff point, there were only 16.1% root lengthening and 39.8% root thickening. CONCLUSIONS: Within the limitations of the present study, it can be concluded that RET yielded high survival and healing rates with a good root development rate. However, clinical meaningful root development after RET was unpredictable.

Successful pulp revascularization of an autotransplantated mature premolar with fragile fracture apicoectomy and plasma rich in growth factors: a 3-year follow-up.

AIM: This case report demonstrates a positive outcome of the adjuvant use of fragile fracture (FF), which is a technique used to harvest dental pulp stem cells (DPSCs), and platelet-rich plasma (PRP) in a mandibular premolar (tooth 44) with a completely formed root that was transplanted into a surgically created socket and which maintained pulp vitality and function. SUMMARY: After virtual surgical planning, a 3D tooth replica of tooth 44 was fabricated. A surgical socket was created in the position of tooth 14; then, tooth 44 was extracted and the root dentine was abraded using a turbine diamond bur 3 mm from the apex until a circular groove was prepared around the outer circumference of the root; and then, an FF was performed without damaging the pulp tissue. PRP was placed in the socket, after which the donor tooth was inserted in the recipient area. At 2 weeks post-treatment, orthodontic traction was applied. At 3-year follow-up, the tooth had adequate alignment and was asymptomatic. Response to pulp testing was positive, and the presence of pulp canal obliteration was observed as a sign of pulpal healing. KEY LEARNING POINTS: Autotransplantation is a good alternative for replacing missing teeth, with repair of tissues and pulp revascularization. Revascularization of an autotransplanted mature tooth using the fragile fracture technique and PRP scaffold is a feasible option and might have positive effects on the long-term outcome of the procedure. Including completely formed teeth as donors in autotransplantation, maintaining vitality and their functions is an option that warrants further study.

A comparison of two pulp revascularization techniques using platelet-rich plasma and whole blood clot.

AIM: The aim of this preliminary study was to compare outcomes of two regenerative endodontic protocols in necrotic teeth with open apices. METHODOLOGY: Forty teeth with open apices in patients with an age range of 15-54 were randomly distributed in two groups: group 1, with whole blood clot in the canal (n=20) and group 2, whole blood with Platelet rich plasma (PRP) in the canal (n=20). Clinical and radiological follow up assessments were undertaken over a period ranging from 6 months to one year. Radiographic Root Area (RRA) was measured using the freeware ImageJ. Statistical analysis was performed using the independent samples t test and the Chi-squared test, the significance level was set at p=0.05. RESULTS: There was no difference in the percentage change in RRA between the PRP group and whole blood-clot + PRP group. CONCLUSION: Whole blood clot and PRP are comparable on the grounds of percentage change in RRA and there is no statistically significant difference between the two in a follow-up period of up to one year.

Promotion effect of erythropoietin on immediate revascularization of replanted teeth in rats / 吉林大学学报(医学版)

Objective: To investigate the expression of vascular endothelial cell growth factor (VEGF) in the immediate replantation of pulp healing in the rats, and to clarify the effect and its mechanism of erythropoietin (EPO) on immediate pulp reconstruction in the rats. Methods: Eighty 4-week-old healthy male Wistar rats were randomly divided into non-tooth extraction group, negative control (normal saline) group, positive control (gentamicin) group and EPO group; there were twenty rats in each group. The teeth in each group were immersed in its corresponding solution for 4 min before replantation. Four rats were killed on the days 3, 7, 14, 21 and 28, respectively, and the specimens were made in the operation area. HE staining was used to observe the pulp revascularization in different time periods. Immunohistochemical staining was used to observe the protein expression levels of VEGF in odontal tissue of the rats in each group in different time periods. Results: The HE staining results showed that compared with non-tooth extraction group, the pulp tissue of replanted teeth of the rats in normal saline group had more inflammation, less root development, less restorative dentin and cementum deposition, and wider apical pores; the inflammation of pulp tissue of replanted teeth of the rats in gentamicin group and EPO group was mild, and the root development was relatively good; there were more deposits of restorative dentin and cementum, and the apical pores were narrowed. The immunohistochemical results showed that compared with non-tooth extraction group, the positive expressions of VEGF in odontal tissue of the rats at the days 3, 7 and 14 in the other groups were strong. Afterwards, the positive expression levels of VEGF were decreased gradually with the prolongation of time. The average optical density (AOD) of VEGF positive area indicated that EPO group > gentamycin group > normal saline group > non-tooth extraction group. Compared with non-tooth extraction group, the protein expression levels of VEGF in odontal tissue of the rats in normal saline group, gentamicin group and EPO group at 3, 7, 14 and 21 d after operation were significanty increased (P0.05). Compared with normal saline group, the protein expression levels of VEGF in odontal tissue of the rats in gentamicin group and EPO group at 3, 7, 14 and 21 d after operation were significantly increased (P0.05). Compared with gentamicin group, the protein expression levels of VEGF in odontal tissue of the rats in EPO group at every time points had no significant differences (P>0.05). Conclusion: EPO can increase the expression of VEGF, induce angiogenesis in pulp tissue, and provide the rich vascular bed for replantated teeth, so as to exert the potential of dental pulp defense and repair, and promote the healing of replanted teeth.

Regenerative endodontics: clinical application status and future perspective / 中华口腔医学杂志

Regenerative endodontic therapy aiming at restoring dentin-pulp complex has been a hot research topic in recent years. Currently, only pulp revascularization has been applied clinically, while stem cell transplantation and cell homing have not been applied in clinical practice. After many years of basic research and clinical practice, regenerative endodontic therapy has made progress. However, it also exposed some problems including confusion of concepts, improper selection of indications, incomplete evaluation criteria. This article summarizes and discusses the current situation, problems and future clinical practice of regenerative endodontic therapy.