Strategies to manage permanent non-vital teeth with open apices: a clinical update

Tomographic evaluation of apexogenesis with human treated dentin matrix in young permanent molars: a split-mouth randomized controlled clinical trial

BACKGROUND

The concept of vital pulp therapy (VPT) of immature permanent teeth has evolved in recent years. There has been a great tendency towards investigating new pulp capping materials for perfect imitation for natural dentin-pulp complex formation process and restoring the normal tissue's characteristics. Therefore, this study aimed to assess the clinical and tomographic outcomes of apexogenesis with human treated dentin matrix (hTDM) compared to mineral trioxide aggregate (MTA).

MATERIALS AND METHODS

40 bilateral deep carious young mandibular first permanent molars (FPMs) in 20 healthy children aged between 6 and 8 years old were randomly allocated into 2 groups in which the FPMs treated with hTDM and MTA after pulpotomy procedure. The children were followed up clinically at 3, 6, 12, and 18 months. Tomographic evaluation was performed at baseline and 18-month evaluation period.

RESULTS

The overall clinical success rate was 100% in both groups. Regarding tomographic evaluation, the mean differences in root length, periapical diameter and area were statistically significant in each individual group but without statistically significant differences between both groups.

CONCLUSION

Human TDM hydrogel could be considered a promising pulpotomy agent for immature permanent teeth.

TRIAL REGISTRATION

The current clinical trial was recorded at clinicaltrials.gov, NCT06116695, 27/10/2023, Retrospectively registered.

Postoperative Outcomes in Surgical Endodontic Treatment Using Various Root-End Filling Materials for Immature Root Apices

The present case series describes the postoperative outcomes of surgical endodontic treatment in teeth with immature root apices using different root-end filling materials. Three cases involving young patients with discolored and non-vital teeth were treated using varied approaches: no root-end filling, mineral trioxide aggregate (MTA), and Biodentine (Septodont, Saint-Maur-des-Fossés, France). Each case included comprehensive pre-surgical assessments, conservative non-surgical root canal treatments, and periapical surgeries performed under magnification. The outcomes were evaluated based on clinical and radiographic success over follow-up periods ranging from six to 24 months. Results demonstrated favorable healing and functional restoration across all cases, highlighting the importance of individualized treatment plans, meticulous surgical techniques, and rigorous postoperative care. The findings underscore the efficacy of contemporary root-end filling materials like MTA and Biodentine in promoting periapical healing and bone regeneration while also emphasizing the necessity for personalized approaches in managing immature root apices. Further research is recommended to optimize these treatment protocols.

Successful retreatment of a maxillary central incisor with a wide-open apex using MTA to fill the entire canal: 24-year follow-up

Managing teeth with open apices can be a challenging scenario for clinicians. This case report describes the 24-year follow-up of a maxillary central incisor that failed to develop after a traumatic injury resulting in a wide-open apex. A 10-year-old girl presented complaining of discomfort in her upper teeth. Tooth #9 had received a traumatic blow several years before and was discoloured with a resin composite restoration on the mesio-incisal edge. The tooth was painful to percussion and palpation. An inadequate root canal filling and incomplete root formation were observed on the initial periapical radiograph. Root canal retreatment was initiated, and the canal filled entirely with mineral trioxide aggregate (MTA) because of the extremely wide canal and open apex. The patient was asymptomatic at the 24-year follow-up with the cone beam computed tomography and periapical radiographs demonstrating the stability of the MTA.

Is Revascularization the Treatment of Choice for Traumatized Necrotic Immature Teeth? A Systematic Review and Meta-Analysis

Regenerative endodontic treatment (RET) has been considered a reliable procedure to treat immature necrotic teeth; however, the effect of dental trauma on the prognosis of RET is questionable. This systematic review aimed to evaluate the current level of evidence for revascularization techniques (the RET) in the management of traumatized necrotic immature permanent teeth with or without periapical radiolucent areas. Four electronic databases-PubMed, Web of Science, Scopus, and Embase-were searched until November 2022. Only randomized clinical trials, cohort studies, and case-control studies with a minimum of 10 cases and 12 months of follow-ups were included. The search identified 363 preliminary results. After discarding the duplicates and screening the titles, abstracts, and full texts, 13 articles were considered eligible. The results showed that RET techniques seemed to have high survival and success rates, 93.8% and 88.3%, respectively, in the treatment of traumatized necrotic immature permanent teeth. Root maturation with RET techniques seemed to be lower in traumatized teeth. Future studies are needed to evaluate root maturation in traumatized teeth using 3-dimensional radiographic evaluations. In addition, the lack of literature on the studies comparing RET and apexification (calcium hydroxide or an MTA) in the treatment of traumatized necrotic immature teeth highlights the necessity for high-level clinical studies comparing these treatment modalities.

Regenerative endodontic therapy for external inflammatory lateral resorption following traumatic dental injuries: Evidence assessment of best practices

BACKGROUND

External inflammatory lateral resorption (EILR) following dental trauma is a severe complication that can lead to significant root loss and tooth extraction.

OBJECTIVE

The aim of this project was to review current evidence in the literature on regenerative endodontic therapy (RET) for EILR following traumatic injuries and assess the best treatment practices.

METHODS

Publications appearing in PubMed, from January 1, 2001 to January 9, 2022 were studied. Inclusion criteria were: (a) Publications in English; (b) Publications on RET and EILR; (c) Teeth subjected to dental trauma; and (d) Presence of intracanal bleeding and blood clots. Exclusion criteria were: (a) Conference proceedings; (b) Lectures; (c) Abstracts; and (d) Letters to editor; (e) Non-English publications.

RESULTS

355 publications were analysed. Nine met all inclusion criteria. In 10 (58.8%) teeth, triple antibiotic paste was used for an average of 26 days. Double antibiotic paste was used in 3 (17.6%) teeth for an average of 14 days. In 3 (17.6%) cases, calcium hydroxide (Ca(OH)₂ ) was used for 14 days and negative pressure irrigation was applied once on 1 (6%) tooth.

DISCUSSION

Using RET to treat EILR has some advantages compared to long term CA(OH)₂ dressing. RET requires shorter dressing time compared to CA(OH)₂ . This can significantly improve patient compliance. Additionally, in immature teeth, RET helps to arrest root resorption leading to continued root maturogenesis and revascularization. It is recommended that a meticulous follow-up should be conducted when RET is performed to assure early detection of treatment failure.

CONCLUSIONS

RET appears to be a good treatment modality producing biologic repair and improving prognosis in cases of EILR in post-traumatic tooth/pulp injuries. The key limitation of this study is that all publications included were either case reports or case series that usually tend to report successful outcome.

Does the Etiology of Pulp Necrosis Affect Regenerative Endodontic Treatment Outcomes? A Systematic Review and Meta-analyses

OBJECTIVE

To evaluate if there is a connection between the causes of pulp necrosis (eg, caries, trauma, dental anomaly) and the success of regenerative endodontic treatment.

METHODS

Electronic databases (PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, Embase) were searched for studies on regenerative endodontic treatment, which used both clinical and radiographic evaluation of root maturation after at least 6 months of follow-up. The search terms "necrotic pulp", "regenerative endodontic treatment", "revascularization", and "revitalization" were combined using Boolean operators. The main journals on endodontics and dental traumatology were additionally hand-searched. Studies were included if they specified the causes of pulp necrosis. The primary question under review was, "Does the cause of pulp necrosis affect the outcome of regenerative endodontic treatment?" Other factors such as tooth type, intracanal medicament, irrigation protocol, use of a collagen matrix, and the type of scaffold were evaluated for possible relation with the outcome. The risk-of-bias assessment for randomized and nonrandomized studies was performed separately, using a modified Cochrane Collaboration's tool and risk of bias in non-randomized studies of interventions-I tool, respectively. Meta-analysis was performed, when possible, between studies comparing treatment outcomes of teeth whose pulp necrosis had different etiology. The search strategy yielded 1197 items. After screening, 18 studies reporting 445 regenerative endodontic treatment cases were included.

RESULTS

The overall success rate for 274 teeth with trauma etiology was 94.8%, for 95 teeth with dens evaginatus etiology was 93.1%, and for 24 teeth with caries etiology was 96%. No significant difference was found between the results of regenerative endodontic treatment among teeth with trauma, dens evaginatus, and caries etiology (P = .055). Meta-analysis of studies comparing teeth with caries vs dens evaginatus and those with trauma vs caries confirmed that there was no evidence for difference in outcomes.

CONCLUSION

Further randomized studies specifically testing such hypothesis are needed to confirm the preliminary results of this review.

A Review Over Benefits and Drawbacks of Combining Sodium Hypochlorite with Other Endodontic Materials

INTRODUCTION

As the root canal system considered to be complex and unpredictable, using root canal irrigants and medicaments are essential in order to enhance the disinfection of the canal. Sodium hypochlorite is the most common irrigant in endodontics. Despite its excellent antimicrobial activity and tissue solubility, sodium hypochlorite lacks some important properties such as substantivity and smear layer removing ability.

OBJECTIVE

The aim of this review was to address benefits and drawbacks of combining sodium hypochlorite with other root canal irrigants and medicaments.

DISCUSSION

According to the reviewed articles, NaOCl is the most common irrigation solution in endodontics. However, it has some drawbacks such as inability to remove smear layer. One of the drawbacks of NaOCl is its inability to remove the smear layer and lack of substantivity.

CONCLUSION

The adjunctive use of other materials has been suggested to improve NaOCl efficacy. Nevertheless, further studies are required in this field.

Vertical root fracture resistance of simulated immature permanent teeth filled with MTA using different vehicles

Background

The aim of the study is to evaluate the resistance vertical root fracture (VRF) of mineral trioxide aggregate (MTA) filled-immature permanent roots by using three different vehicles.

Material and Methods

Forty-extracted human single-rooted mandibular premolars were selected and the root length was standardized to the length of 9 mm. For simulation of immature tooth apices, peeso reamers were introduced into the root canals and the prepared roots were assigned into three experimental groups according the used vehicle (distilled water-DW, prophylene glycol-PG, chlorhexidine-CHX) and control group (n=10). To simulate a periodontal membrane, the apical 7 mm of all roots was covered with wax to obtain a 0.2- to 0.3-mm-thick layer before embedding the roots into acrylic cylinders. A vertical force was applied (1mm/min) using a universal testing machine and the maximum load (F-max) that fracture occurred and the fracture mode (splint or comminuted) was recorded. Data were presented as mean and standard deviations. Statistical analysis was performed using Kruskal-Wallis, Mann-Whitney U Test was used for multiple comparisons.

Results

There were significant differences between fracture strength of experimental groups with that of control group (p<0.05). However, no statistically significant differences were found amongst the fracture strength values of the experimental groups (p>0.05). In all groups, split fracture was the most common fracture mode.

Conclusions

MTA increases resistance of immature permanent teeth to VRF. Based on the results of this study, it can be concluded that mixing MTA with CHX or PG as the vehicle do not alter VRF resistance of simulated immature permanent roots.

Key words:Immature teeth, MTA, vehicle, vertical root fracture.

Cell-free approaches for dental pulp tissue engineering

The standard treatment modality for teeth with irreversibly damaged dental pulp is root canal therapy, which involves complete removal of the soft tissue and obturation with a synthetic material. So far, research studies show that the combination of stem cells with a suitable scaffold material and transplantation into the root canal may result in the generation of pulplike tissue and the formation of tubular dentin. Because of the technical challenges associated with such a procedure, cell-free alternatives that take advantage of the dental pulp's inherent regenerative capacity because of endogenous stem cell populations and bioactive dentin matrix components need to be considered and explored. Following the tissue engineering approach, this includes (1) a bioactive scaffold, (2) growth and differentiation factors from dentin, and (3) the recruitment of stem cells from resident populations within the pulp or from the periapical region. If this concept proved to be successful, cell-free therapies may be a safer, more practical, feasible, and affordable approach to dental pulp regeneration.

Clinical procedures for revitalization: current knowledge and considerations

Revitalization or regenerative treatment approaches in teeth with incomplete root formation and pulp necrosis have become part of the therapeutic endodontic spectrum and should be considered as an alternative to conventional apexification. Ideally, regenerative endodontic procedures allow not only for a resolution of pain, inflammation and periapical lesions, but also for the formation of an immunocompetent tissue inside the root canal which can reconstitute the original biological structure and function of dental pulp and thus lead to an increase in root length, and thickness and strength of previously thin, fracture-prone dentine walls. Common features of regenerative procedures performed in immature teeth with pulp necrosis include (i) minimal or no instrumentation of the dentinal walls, (ii) disinfection with irrigants, (iii) application of an intracanal medicament, (iv) provocation of bleeding into the canal and creation of a blood clot, (v) capping with calcium silicate, and (vi) coronal seal. Although case reports and case series provide promising results, the protocol for regenerative endodontic treatment is not fully established; questions remain regarding the terminology, patient selection and informed consent as well as procedural details, especially on the choice of irrigants, intracanal medicaments and materials for cavity sealing. Animal studies document repair rather than regeneration, which opens the discussion on prognosis and outcome, especially the biological versus the patient-based outcome. This review will provide an overview of the current state of regenerative endodontic therapies, discuss open questions and provide recommendations based on the recent literature.

Efficacy of Biodentine as an Apical Plug in Nonvital Permanent Teeth with Open Apices: An In Vitro Study

The aim of this study was to evaluate the apical microleakage of Biodentine and MTA orthograde apical plugs and to compare the effect of thickness of these biomaterials on their sealing ability. A total of eighty maxillary anterior teeth were used. The apices were removed by cutting with a diamond disc (Jota, Germany) 2 mm from the apical root end in an attempt to standardize the working length of all specimens to 15 ± 1 mm. Both materials were placed in 1–4 mm thickness as apical plugs root canal. Root canal leakage was evaluated by the fluid filtration technique. One-way ANOVA was used in order to determine normality of dispersal distribution of parameters; thereafter, results were analyzed by Kolmogorov-Smirnov test. Overall, between microleakage values of MTA and Biodentine regardless of apical plug thickness, no difference was observed. In terms of plug thickness, a statistically significant difference was observed between the subgroups of MTA and Biodentine (p < 0.05). The apical sealing ability of Biodentine was comparable to MTA at any apical plug thickness.

Adult stem cell-based apexogenesis

Generally, the dental pulp needs to be removed when it is infected, and root canal therapy (RCT) is usually required in which infected dental pulp is replaced with inorganic materials (paste and gutta percha). This treatment approach ultimately brings about a dead tooth. However, pulp vitality is extremely important to the tooth itself, since it provides nutrition and acts as a biosensor to detect the potential pathogenic stimuli. Despite the reported clinical success rate, RCT-treated teeth are destined to be devitalized, brittle and susceptible to postoperative fracture. Recently, the advances and achievements in the field of stem cell biology and regenerative medicine have inspired novel biological approaches to apexogenesis in young patients suffering from pulpitis or periapical periodontitis. This review mainly focuses on the benchtop and clinical regeneration of root apex mediated by adult stem cells. Moreover, current strategies for infected pulp therapy are also discussed here.

Comprehensive management of a complex traumatic dental injury

A 24-year-old female patient presented with complaint of palatal swelling and a sinus tract facial to tooth #22. She reported an injury to the tooth 15 years earlier and no recollection of treatment, although there was evidence of an endodontic access into the crown. Radiographically the root appeared to have stopped developing, and it was associated with a large periapical lesion. After 3 unsuccessful attempts at apexification using calcium hydroxide (CH), further examination including use of cone-beam computed tomography (CBCT) was carried out. The latter allowed for better evaluating the situation and for better planning a more comprehensive treatment plan to include surgical removal of the apical lesion. The large radiolucent area extended from tooth #21 to #23. Using a dedicated software tool developed to be used in conjunction with CBCT, volumetric assessment of the lesion was carried out for healing follow up. The root end was filled from the apical direction with newly developed accelerated silicate cement 4-5 mm into the apical part of the canal. Subsequently, the rest of the canal was filled with the same type of cement. At the 1-year postsurgical follow up, the tooth remained asymptomatic, and using the CBCT volumetric program, bony healing could be demonstrated.

Healing of a tooth with an overinstrumented apex, extensive transportation and periapical lesion using a 5 mm calcium hydroxide apical plug: an 8-year follow-up report

Besides the risk of filling material extrusion throughout the apex, a satisfactory apical seal can be difficult to achieve in canals with open apices or iatrogenic enlargements of the apical constriction. These situations pose a challenge to root canal filling. This paper describes the root canal filling of a maxillary right canine with an overinstrumented apex, complete loss of the apical stop, extensive canal transportation and apical periodontitis. A 5 mm calcium hydroxide apical plug was placed before root canal filling. The plug was made by soaking paper points with saline, dipping the points in calcium hydroxide powder and then applying it to the apex several times, until a consistent apical plug was obtained. The canal was then irrigated with saline in order to remove any residual calcium hydroxide from the root canal walls, dried with paper points and obturated with an inverted #80 gutta-percha cone and zinc oxide-eugenol based sealer by the lateral condensation technique. An 8-year radiographic follow-up showed formation of mineralized tissue sealing the apical foramen, apical remodeling and no signs of apical periodontitis.

The diagnosis and conservative treatment of a complex type 3 dens invaginatus using cone beam computed tomography (CBCT) and 3D plastic models

AIM

To investigate the use of 3D plastic models, printed from cone beam computed tomography (CBCT) data, for accurate diagnosis and conservative treatment of a complex case of dens invaginatus.

SUMMARY

A chronic apical abscess with a draining sinus tract was diagnosed during the treatment planning stage of orthodontic therapy. Radiographic examination revealed a large radiolucent area associated with an invaginated right maxillary central incisor, which was found to contain a vital pulp. The affected tooth was strategic in the dental arch. Conventional periapical radiographs provided only partial information about the invagination and its relationship with the main root canal and with the periapical tissues. A limited-volume CBCT scan of the maxilla did not show evidence of communication between the infected invagination and the pulp in the main root canal, which could explain the pulp vitality. A novel method was adopted to allow for instrumentation, disinfection and filling of the invagination, without compromising the vitality of the pulp in the complex root canal system. The CBCT data were used to produce precise 3D plastic models of the tooth. These models facilitated the treatment planning process and the trial of treatment approaches. This approach allowed the vitality of the pulp to be maintained in the complex root canal space of the main root canal whilst enabling the healing of the periapical tissues.

KEY LEARNING POINTS

Even when extensive periapical pathosis is associated with a tooth with type III dens invaginatus, pulp sensibility tests should be performed. CBCT is a diagnostic tool that may allow for the management of such teeth with complex anatomy. 3D printed plastic models may be a valuable aid in the process of assessing and planning effective treatment modalities and practicing them ex vivo before actually performing the clinical procedure. Unconventional technological approaches may be required for detailed treatment planning of complex cases of dens invaginatus.

MTA resorption and periradicular healing in an open-apex incisor: A case report

This case report describes the periradicular healing and resorption of an unintentional extrusion of mineral trioxide aggregate (MTA) in an open-apex central incisor. A 22-year old female with a symptomatic open-apex right maxillary central incisor associated with a periradicular lesion was referred for evaluation and treatment. After chemomechanical debridement, the apical third of the root canal was filled with MTA to create an apical plug. Postoperative radiographs showed the extrusion of MTA into the periradicular lesion. The tooth was then restored with a post and crown. At the 2-year follow-up, the tooth was asymptomatic and radiographs revealed complete healing of the periradicular area. At the 7-year follow-up, complete resorption of the extruded MTA was evident. The results of this case study indicate that complete resorption of extruded MTA is possible in the long term; however, the extrusion of MTA in open-apex tooth should still be avoided.