Effects of Doxycycline-Loaded NO-Releasing Nanomatrix Gel on Delayed Replanted of Rat Molar.

BACKGROUND/AIM: Tooth avulsion and delayed replantation may cause inflammatory responses and root resorption of the tooth. The aim of this study is to investigate the effect of a doxycycline-loaded nitric oxide-releasing nanomatrix (DN) gel on the delayed replantation of avulsed rat teeth, with a focus on assessing the gel's potential to promote regeneration and inhibit complications associated with the replantation process. MATERIALS AND METHODS: Twenty-four right maxillary first molars from male Sprague-Dawley rats were atraumatically extracted using sterile extraction forceps. The molars were dried for 1 h at room temperature (approximately 23 °C) and divided into four groups according to the root conditioning methods after extra-alveolar 60-min drying: Group 1, no root conditioning treatment prior to replantation; Group 2, soaking in 2% NaF solution for 5 min before replantation; Group 3, 5-min soaking in NO gel and injection of the gel into the alveolar socket; Group 4, 5-min soaking in DN gel and injection of the gel into the alveolar socket before replantation. The animals were euthanized four weeks after the operation and the specimens were evaluated histologically. RESULTS: The use of NO gel alone showed better anti-inflammatory and periodontal effects than the control group, but it did not show a significant effect compared to the group using NaF. When using NO gel loaded with doxycycline, it showed a significant anti-inflammatory effect compared to the control group and showed a similar inhibitory effect to the group using NaF. CONCLUSIONS: Within the limits of this study, in delayed replantation situations, the control of inflammatory resorption and replacement resorption is an important factor for achieving a better prognosis of replanted teeth. Root surface treatment with DN gel decreased root resorption after delayed replantation.

Application of oxygen saturation test after replantation of avulsed immature permanent teeth: A prospective observational study.

INTRODUCTION: The evaluation of pulp status is crucial for avulsed immature permanent teeth following replantation. In addition to commonly used clinical and radiographic examinations providing clinical evidence, oxygen saturation test may offer valuable assistance. The aim of this study was to analyze the efficacy of pulse oximeter in evaluating pulp status in avulsed and replanted immature permanent teeth. METHODS: A prospective observational study was performed including 51 avulsed and replanted immature permanent teeth. Routine clinical and radiographic examinations were performed and used as the basis for diagnosis of pulp status during the 1-year follow-up period. Meanwhile, the oxygen saturation values of these teeth were recorded using a modified pulse oximeter at each visit. RESULTS: Seven teeth completed pulp revascularization (success group), whereas 44 teeth failed to revascularize (failure group). Abnormal clinical and/or radiographic manifestations in the failure group were observed at an average period of 42.7 days, which was too late because a high incidence of inflammatory root resorption (43.18%) had occurred. For oxygen saturation tests, teeth in the success group showed an immediate post-replantation oxygen value of 70.71 ± 3.35, then an upward trend starting from the 2-week post-replantation visit, and a significantly increased final value of 81.86 ± 2.34 at the 1-year visit. In contrast, no increase trend was found for teeth in the failure group as abnormal clinical and/or radiographic manifestations emerged. CONCLUSION: An oxygen saturation test is a reliable diagnostic method by which to evaluate pulp status of avulsed teeth as early as 2 weeks after replantation.

The effect of fibroblast growth factor-2 on the outcomes of tooth replantation: A systematic review of animal studies.

Background/Aim: The ideal treatment of tooth avulsion is replantation. However, replanting teeth may lead to root resorption. Fibroblast growth factor-2 (FGF-2) is a cytokine that plays an important role in wound repair and tissue regeneration. Recently, FGF-2 has been studied a potential regenerative agent to prevent root resorption and ankylosis. The aim of this review is to analyze and summarize the currently available literature focusing on using FGF-2 based regenerative modalities to improve the outcomes of tooth replantation. Materials and Methods: An electronic search was conducted via PubMed/Medline, Google Scholar and ISI Web of Knowledge, using the Medical Subject Headings (MeSH) terms "Basic fibroblast growth factor," "Fibroblast growth factor-2," "tooth replantation," and "replantation" for studies published between January 2001 and June 2021. Data was extracted and quality assessment was carried using the ARRIVE guidelines. Results: Nine animal studies were included in this review. In six studies, FGF-2 had a favorable effect on the tissue regeneration around roots of replanted teeth when compared to other treatment groups. However, quality assessment of the studies revealed many sources of bias and deficiencies in the studies. Conclusions: Within the limitations of this study, it may be concluded that FGF-2 may improve the outcomes of delayed replantation of avulsed teeth. However, more long-term animal studies, with improved experimental designs, and clinical trials are required to determine the clinical potential of the growth factor in improving the outcomes of delayed tooth replantation.

The Apical Tooth Replantation with Surgical Intrusion Technique (ATR-SIT) for Regenerative Treatment of Hopeless Teeth: A Report of Two Cases.

The aim of the present clinical report is to introduce a novel surgical procedure, the "Apical Tooth Replantation with Surgical Intrusion Technique" (ATR-SIT) for managing teeth with hopeless prognosis compromised with a severe endodontal-periodontal lesion, pathologic tooth migration, and gingival recession. Two cases are presented managing teeth diagnosed with a hopeless prognosis. ATR-SIT involves tooth extraction, extra-oral root debridement, root surface conditioning, apicectomy, retrograde filling and the application of enamel matrix derivatives prior to reimplantation. Following reimplantation, the teeth are covered with a combination of autogenous bone chips and bone substitute materials, covered with resorbable membranes. Following ATR-SIT, the patients received either orthodontic treatment or tooth-supported fixed dental prostheses. The described ATR-SIT effectively improved the initially hopeless prognosis of the teeth and maintained periodontal health over time, evidenced by favourable clinical and radiographic outcomes. ATR-SIT might be a potential alternative to tooth extraction of hopeless teeth in patients with stage IV periodontitis.

Early revascularization activates quiescent dental pulp stem cells following tooth replantation in mice.

Introduction: The intentional perforation of the pulp chamber floor before tooth replantation promotes pulpal healing by facilitating the revascularization of the pulp cavity. This study aimed to elucidate the effects of this method on the dynamics of quiescent dental pulp stem cells (DPSCs). Methods: The right and left maxillary first molars of Crlj:CD1 mice and TetOP-histone 2B (H2B)-green fluorescent protein (GFP) mice were extracted. The left molars were immediately replanted as the control group (CG), whereas the pulp chamber floor of the right molars were perforated before the tooth was replanted as the experimental group (EG). Immunohistochemistry for Nestin and GFP, and quantitative RT-PCR for Nestin, Opn, CD11c, and Oct3/4 mRNA were performed. Results: The rate of Nestin-positive perimeter along the pulp-dentin border in the EG tended to be higher than that of the CG at days 5 and 7 and was significantly increased between days 3 and 7. The rate of GFP-positive cells in the EG was significantly higher than that of the CG at days 5 and/or 7 in the mesial and middle coronal pulp. CD11c mRNA in the EG at day 5 was significantly higher than that of the CG and tended to be higher than that of the CG during the observation period. Oct3/4 mRNA expression in the EG was significantly higher than that of the CG at day 7. Conclusions: The current experimental model demonstrated the promotion of the survival of DPSCs and their differentiation into odontoblast-like cells (OBLCs). Thus, the use of this model is expected to clarify the crosstalk mechanism between immune cells, including macrophages and dendritic cells, and DPSCs with regards to pulpal healing after tooth replantation. It also provides insight into the differentiation process of DPSCs into OBLCs.

Avulsion Injuries: Assessment and Management.

Avulsion injuries, though relatively uncommon, are one of the most serious of dentoalveolar injuries. Replantation at the scene of the incident is almost always the treatment of choice whenever possible. This paper outlines a step-by-step approach for the management of avulsion injuries, including a splinting protocol. This aims to support general dental practitioners in feeling more confident with managing these injuries.

The Top 100 Most-Cited Articles on Permanent Teeth Avulsion: A Bibliometric Analysis.

INTRODUCTION: Knowledge of bibliometric indices on the avulsion of permanent teeth can help researchers to identify gaps in the literature. The aim of this study was to analyze the bibliometric characteristics of the 100 most-cited articles on the avulsion of permanent teeth. MATERIALS AND METHODS: Two researchers conducted an unfiltered search in the Core Collection section of the Web of Science (WoS-CC) database. The following data were extracted: position in the citation list, total number and density of citations, title, authors, institution, country, year of publication, journal, keywords, study design, tooth storage medium, and other topics of interest. Bibliometric networks were generated and analyzed using the VOSviewer software. Descriptive analysis and a Poisson regression analysis were performed (P < .05). RESULTS: The number of citations per article varied between 31 and 407. The average was 70.05, and 13 articles received more than 100 citations. J.O. Andreasen (n = 13) and M. Trope (n = 15) were the authors who contributed most often to publications. The United States was the country with the highest number of articles (n = 31). Authors associated with the University of Copenhagen, Denmark (n = 9) and University of North Carolina, USA (n = 10) showed higher productivity. In vitro/animal model studies were the most frequent study designs (n = 50), and the most-discussed topic of interest was prognosis (n = 47). There was strong clustering among 13 research groups. CONCLUSION: Observational studies, published by authors from Europe and about prognosis or treatment presented more citation ratio in WoS-CC. Clinical studies on permanent tooth avulsion are needed to increase the quality of scientific evidence and provide insights for health professionals and public policy makers.

Does photobiomodulation on the root surface decrease the occurrence of root resorption in reimplanted teeth? A systematic review of animal studies.

This review aimed to answer the following question "Does photobiomodulation treatment of the root surface decrease the occurrence of root resorption in reimplanted teeth?" Electronic searches were performed in the MEDLINE/PubMed, Cochrane Library, Scopus, Web of Science, Embase, and Grey Literature Report databases. Risk of bias was evaluated using SYRCLE Risk of Bias tool. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) tool was used to assess the certainty of evidence. In total, 6 studies were included. Five studies reported a reduced occurrence of root resorption in teeth that received photobiomodulation treatment of the root surface prior to replantation. Only 1 study reported contradictory results. The photobiomodulation parameters varied widely among studies. GRADE assessment showed a low certainty of evidence. It can be inferred that photobiomodulation treatment of the root surface prior to replantation of teeth can reduce the occurrence of root resorption. Nonetheless, further clinical studies are needed. Trial Registration: PROSPERO Identifier: CRD42022349891.

Effect of intra-alveolar delivery of Frondoside A on inflammatory response of delayed tooth replantation.

BACKGROUND/AIM: Frondoside A is a sea cucumber extract which is well known for its anti-inflammatory and immunomodulatory properties. The purpose of this study was to evaluate the effect of Frondoside A application in the alveolar socket on inflammatory responses after delayed replantation in rat teeth. MATERIALS AND METHODS: Human periodontal ligament cells were cultured and exposed to Frondoside A. Cell-counting kit-8 assay was performed to evaluate the cell viability and nitric oxide assay was performed to assess the anti-inflammatory effect of Frondoside A. Molars were extracted from 32 Sprague-Dawley rats and randomly divided into control and Frondoside A groups. After 30 min of extra-oral dry time, molars were replanted. In the Frondoside A group, Frondoside A solution was applied in the alveolar socket before replantation. The animals were sacrificed after 28 days and histologically and immunohistochemically evaluated. RESULTS: 0.5 µM Frondoside A showed higher cellular viability at 6 h and lower production of nitric oxide compared with other Frondoside A solutions (p < .05). The Frondoside A group demonstrated lower inflammatory resorption scores in both middle 1/3 and apical 1/3 of root compared to the control group (p < .05). The Frondoside A group showed lower levels of expression in both cathepsin K and CD45 compared with the control group (p < .05). CONCLUSIONS: Within the limits of this study, intra-alveolar delivery of Frondoside A alleviates inflammatory root resorption in delayed replantation of rat teeth.

Parents' knowledge of emergency management of avulsed permanent teeth in children and adolescents in the State of Qatar: a questionnaire cross-sectional study.

PURPOSE: To elucidate the level of parental knowledge in Qatar regarding the management of avulsed teeth. METHODS: A self-administered questionnaire was completed by 400 parents attending their children's routine dental appointments. The questionnaire comprised of items on sociodemographics, parents' prior knowledge on management of avulsion, parents' willingness to replant avulsed teeth at the site of injury, and parents' opinion as to the best format for future parental education on the management of dental trauma. Univariate and multivariate logistic regressions were employed to assess the association between sociodemographic status and knowledge in the management of avulsion. RESULTS: The overall mean score of parents' knowledge was (23%). Only 23.3% (n = 93) of parents thought that it was possible to reinsert an avulsed permanent tooth. Out of those, only 12.9% (n = 12) indicated willingness to reinsert the tooth back into its socket, while 48.4% (n = 49) indicated that an avulsed tooth should be stored using physiological media. Less than one third (27.8%) indicated that they would seek professional help within 30 min. Males were less likely to give favourable answers when compared to females (OR = 0.43, 95% CI = 0.22-0.84). Age groups "31-40" years and "41-50" years were more likely to give favourable answers when compared to 20-30 years age group (OR = 2.8, 95% CI = 1.05-8.0and OR = 3.8, 95% CI = 1.3-11.48; respectively). CONCLUSION: This study highlights critical deficiencies in parental knowledge on the management of tooth avulsion and the need to improve parents' knowledge by developing easily accessible onsite emergency management tools.

Conhecimento de acadêmicos de Odontologia acerca da avulsão dentária / Knowledge of dental students about tooth avulsion

Objetivo: verificar o conhecimento de acadêmicos de Odontologia de uma instituição de ensino superior da Paraíba acerca da avulsão dentária. Métodos: foi realizado um estudo transversal, no qual 64 acadêmicos responderam um formulário com perguntas objetivas relativas a dados sociodemográficos, período de formação do curso e conhecimento e condutas em casos de avulsão dentária. Foi realizada análise descritiva de frequência absoluta e relativa dos dados (SPSS, v. 20.0). Resultados: a maioria dos acadêmicos recebeu informações sobre avulsão dentária em aulas ministradas no curso (86%) e indicaria a irrigação com soro fisiológico seguida de reimplante quando da ocorrência do trauma há menos de uma hora (64,1%) e há mais de uma hora (43,8%). O tratamento endodôntico foi indicado, independentemente do tempo do dente fora do alvéolo, por 34,4% da amostra. A contenção rígida foi a mais indicada para o dente reimplantado (48,4%) e seu tempo mínimo de proservação radiográfica respondido pela maioria dos pesquisados foi de 6 meses (48,4%). Conclusões: apesar de a maioria dos acadêmicos ter recebido informações acerca da temática, o conhecimento foi considerado insuficiente em relação a condutas referentes ao reimplante dentário, indicação do tratamento endodôntico, tipo de contenção e tempo de proservação.

Objective: to verify the knowledge of dental students from a Higher Education Institution of Paraíba about dental avulsion. Methods: a cross-sectional study was carried out, in which 64 students answered a form with objective questions regarding sociodemographic data, course period, knowledge and conduct in cases of tooth avulsion. Descriptive analysis of absolute and relative frequency of data was performed (SPSS, v. 20.0). Results: most students received information about dental avulsion during the graduation classes (86%) and would indicate irrigation with saline solution followed by reimplantation when the trauma occurred less than one hour (64.1%) and more than one hour (43.8%). Endodontic treatment was indicated, regardless of the time the tooth was out of the dental socket, according 34.4% of the sample. Rigid retention was the most indicated for the reimplanted tooth (48.4%) and six months was the minimum radiographic follow-up time answered by most students (48.4%). Conclusions: although most students have received information about the topic, the knowledge was considered insufficient in relation to some aspects of the protocols recommended for emergency care for dental avulsion, with emphasis on behaviors related to dental reimplantation, indication of endodontic treatment, type of containment and follow-up.

Current Trends in Intentional Replantation Treatment Among Endodontists and Postgraduate Students in India, the United States of America, and the United Kingdom: A Cross-Sectional Study.

Objective This study aimed to investigate the knowledge, attitude, and practices (KAP) of intentional replantation among postgraduate students and endodontists in India, the United States of America, and the United Kingdom. Materials and methods The sample size was estimated using G*Power. Based on the pilot study done before with 60 participants, a sample size of 928 was obtained. The survey consisted of 22 questions, which were finalized after content validation by two endodontic experts. It was circulated through multiple online social platforms such as Instagram, Facebook, WhatsApp, and other online dental communities/channels. The respondents were questioned about the case selection, extraction methods, antibiotic therapy, patient acceptance level, operator preference, prognostic indicator, and various other steps in the intentional replantation treatment modality. The data for this KAP survey were organized in an Excel sheet, and statistical analysis was done using the Chi-squared test. Analysis of descriptive and inferential statistics was conducted using SPSS version 20.0 (IBM Inc., Armonk, New York). A p-value of <0.05 was considered significant. Results A strong statistical difference was found in the KAP of the practitioners in different countries. The vast majority (72.7%) considered intentional replantation as an adjunct treatment modality rather than a last resort. A total of 76.5% of the respondents preferred replantation of the tooth into the socket within 15 minutes, and 86.4% of the participants regarded replantation as the most cost-effective treatment modality. Ultrasonics (76.8%) was most commonly chosen for retrograde preparation, and Biodentine (60.1%; Septodont, Saint-Maur-des-Fossés, France) as root-end filling material. Conclusion It can be concluded that a broad majority of practitioners in different countries view intentional replantation as an adjunct treatment modality rather than a last resort. Thus, intentional replantation seems to be a promising option for preserving the natural dentition of teeth with high survival rates and better outcomes.

Long Term Outcome of Avulsed Immature Mandibular Incisor with Progressive External Root Resorption: 9 Years Follow-Up.

Background: Avulsion of permanent teeth is the most common in young permanent dentition. Replantation of immature teeth after avulsion represents a major challenge in terms of treatment management and long-term prognosis. This case report describes 9 years of follow-up for an avulsed and replanted immature mandibular lateral incisor with progressive external root resorption. Methods: A 7-year-old patient following an accident in which his mandibular left central incisor was avulsed and replanted within one hour after being stored in a physiological storage medium. However, radiographic examination conducted six weeks after the dental injury revealed inflammatory root resorption of the replanted tooth #31. To address root resorption, endodontic treatment was performed involving the use of calcium hydroxide as an intracanal medication for a short period of time, followed by root canal obturation with mineral trioxide aggregate placed below the crestal bone margin. Results: Three months later the root resorption had progressed. Consequently, a decision was made to perform periodontal surgery. While the long-term follow-up revealed that the inflammatory root resorption had damaged half of the root, the tooth remained functional and aesthetically favourable. Conclusions: Despite the challenges associated with replantation of an immature tooth following avulsion, this case demonstrated favourable outcomes. The tooth maintained its functionality, exhibited favourable aesthetic, and the dimensions of the alveolar ridge were preserved, allowing for the physiological expansion of the dental arch.

Success of replantation of avulsed teeth using human colostrum as an interim storage medium.

Objectives: Tooth avulsion is defined as total tooth displacement from the alveolar socket; the best treatment is replantation of the tooth. Human milk influences body health, growth, and development related to the presence of micro and macro nutrient components. This study assessed the effects of human colostrum as a storage medium on the success of tooth replantation. Methods: The upper left incisor of 30 adult male Wistar rats was extracted, and the rats were divided into three groups according to the storage medium of the extracted tooth for replantation: Hank's balanced salt solution (HBSS), tap water, and colostrum groups. The MTT cell viability assay was conducted, and histological evaluation and histomorphometric analyses were performed on postoperative day 45 for identification of pulp necrosis, periodontal hyalinization, percentage of resorbed area, and the periodontal ligament attachment. Results: The colostrum medium showed a higher percentage of cell viability followed by HBSS with statistical significance. Histological findings of the replanted avulsed tooth that soaked in tap water as storage medium showed obvious external and internal root resorption. Pulp necrosis and periodontal ligament hyalinization and with a significant differences values in comparison to HBSS and colostrum groups (p > 0.05), whereas the colostrum group showed new well-reattached periodontal ligament with normal pulp and no evidence of root resorption. Conclusion: Tooth loss is minimized by using human colostrum as storage medium in replantation of an avulsed tooth after a 1 h period compared to HBSS and water.

The effect of intentionally perforating the floor of the pulp chamber on pulpal healing after tooth replantation in mice.

OBJECTIVES: Shortening the root of a mouse molar prior to tooth replantation results in early revascularization in the pulp cavity and activation of the dental pulp quiescent stem cells. This study aimed to validate the effects of pulp chamber floor perforation on pulpal healing after tooth replantation as a strategy to promote early revascularization into the pulp. METHODS: The maxillary first molars of three-week-old Crlj:CD1 mice were extracted and repositioned into the original socket: the left teeth were immediately replanted (control group: CG), whereas the floor of the pulp chamber of the right teeth was perforated with a tungsten carbide bur before tooth replantation (experimental group: EG). The samples were collected from three days to eight weeks postoperatively. In addition to the TUNEL assay, immunohistochemistry for Nestin, CK14, and Ki-67 was conducted. RESULTS: In the EG, early revascularization occurred with a decrease in apoptosis and an increase in cell proliferation, facilitating pulpal healing, compared with the CG. The rate of Nestin-positive perimeter in the distal root significantly increased on days 5 and 14 and the amount of Nestin-positive hard tissue increased on day 14. However, on day 7, the number of epithelial cell rests of Malassez in the EG significantly decreased, making the EG susceptible to ankylosis at the floor. CONCLUSIONS: Intentionally perforating the floor of the pulp chamber provides a route for early revascularization, resulting in better pulpal healing after tooth replantation.

Evaluation of delphinidin as a storage medium for avulsed teeth.

BACKGROUND: Delphinidin (DP), an anthocyanidin found in blueberries, has antioxidant and anti-inflammatory effects. This study aimed to investigate the efficacy of DP as a storage medium for avulsed teeth. METHODS: Human periodontal ligament cells were cultured and exposed to DP solution (10, 50, and 100 µM), Dulbecco's modified Eagle's medium, Hank's balanced salt solution and tap water. Cell counting kit-8 assays were performed after 0.5, 1, 6, and 24 h to measure the cell viability. Nitric oxide assays and gelatin zymography were performed to evaluate the anti-inflammatory effects of DP. Reverse transcription-polymerase chain reaction was used to determine the expression levels of inflammatory cytokines. RESULTS: The viability of periodontal ligament cells was greatest at 100 µM DP. At 1 h, 100 µM DP decreased nitric oxide synthesis (p < .0167). Matrix metallopeptidase-9 activity was inhibited by DP in a dose-dependent manner (p < .0167). Moreover, treatment with 100 µM DP decreased the expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 in periodontal ligament cells (p < .0167). CONCLUSIONS: Within the limits of this study, DP preserved the viability and suppressed the inflammatory response of periodontal ligament cells. These findings suggest that DP could be promising for preservation of avulsed teeth.

Outcome of intentional replantation of endodontically treated teeth with periapical pathosis: A systematic review and meta-analysis.

The purpose of the present review was to examine success, survival and failure following intentional replantation of endodontically treated teeth with existing periapical pathosis and to determine the factors that might affect the outcome of replantation. Clinical trials, longitudinal studies, case series with >10 cases and at least 1-year follow-up were included. The average rate of success following intentional replantation was 77.23%. Meta-analysis revealed the mean weighted survival to be 85.9% (95% CI: 79.6-91.2) Common complications include inflammatory root resorption (0%-27%) and ankylosis (0%-25%). Variables influencing successful outcome include extra alveolar dry time <15 min; root-end resection (2-3 mm) and cavity preparation (3 mm); manipulation of the tooth using the crown only; and use of an appropriate storage media. The review concludes that intentional replantation is a viable treatment option with acceptable survival rates for endodontically treated teeth with periapical pathosis.

Diagnosis and Treatment of an Incomplete Crown-Root Fracture with Intentional Replantation: A Case Report.

Acute traumatic injuries to the maxillary incisors may lead to a crown-root fracture. If the fracture is left untreated, the fracture line will propagate and extend apically, resulting in microbial contamination of the attachment apparatus and subsequent bone loss. In cases with extensive periodontal involvement, extraction has been suggested. However, bonding and sealing the fracture line with a biocompatible material seems to be an effective alternative treatment option. In this case report, management of a central incisor with an incomplete crown-root fracture that showed signs and symptoms of vertical root fracture is discussed. As the extension of the fracture line was not clear, intentional replantation and sealing the fracture line with a glass ionomer was performed. The tooth showed no signs and symptoms at six-month follow up, and the radiographic examination exhibited substantial bone repair.

Intentional Replantation Of Mandibular First Molar With Two Years Follow Up- Case Report.

BACKGROUND: Intentional replantation (IR) is a reliable and predictable treatment option for cases with failed non-surgical root canal treatment. The success of IR is found to be 52-95%. The current case is of 35years old female who presented with severe pain and swelling in lower right first mandibular molar with previously initiated non-surgical root canal treatment that resulted in instrument separation in mesio-buccal canal. Periapical radiograph showed rarefactions at furcation area, mesial and distal root apices. It was decided to complete the non-surgical root canal treatment followed by intentional replantation and retrograde filling with MTA. The tooth was found to be asymptomatic after two years follow up and periapical radiographs depicted complete healing. Intentional replantation with careful case selection is a successful, easy and reliable treatment option for hopeless cases. Atraumatic extraction, minimum extra-alveolar time and aseptic techniques during the procedure are the key factors for success of the procedure.

Role of osteopontin in the process of pulpal healing following tooth replantation in mice.

Introduction: The role of osteopontin (OPN) following severe injury remains to be elucidated, especially its relationship with type I collagen (encoded by the Col1a1 gene) secretion by newly-differentiated odontoblast-like cells (OBLCs). In this study, we examined the role of OPN in the process of reparative dentin formation with a focus on reinnervation and revascularization after tooth replantation in Opn knockout (KO) and wild-type (WT) mice. Methods: Maxillary first molars of 2- and 3-week-old-Opn KO and WT mice (Opn KO 2W, Opn KO 3W, WT 2W, and WT 3W groups) were replanted, followed by fixation 3-56 days after operation. Following micro-computed tomography analysis, the decalcified samples were processed for immunohistochemistry for Ki67, Nestin, PGP 9.5, and CD31 and in situ hybridization for Col1a1. Results: An intense inflammatory reaction occurred to disrupt pulpal healing in the replanted teeth of the Opn KO 3W group, whereas dental pulp achieved healing in the Opn KO 2W and WT groups. The tertiary dentin in the Opn KO 3W group was significantly decreased in area compared with the Opn KO 2W and WT groups, with a significantly low percentage of Nestin-positive, newly-differentiated OBLCs during postoperative days 7-14. In the Opn KO 3W group, the blood vessels were significantly decreased in area and pulp healing was disturbed with a failure of pulpal revascularization and reinnervation. Conclusions: OPN is necessary for proper reinnervation and revascularization to deposit reparative dentin following severe injury within the dental pulp of erupted teeth with advanced root development.