The treatment of immature permanent teeth with necrotic pulp represents a significant challenge in endodontics due to the unique structural vulnerabilities of these teeth [1]. Immature teeth often present with thin dentinal walls, a wide-open apex, and incomplete root development, making them prone to fracture and difficult to treat using conventional methods. Historically, apexification has been the cornerstone treatment for such cases. Techniques employing calcium hydroxide or mineral trioxide aggregate (MTA) have been used extensively to induce a hard tissue barrier at the root apex, facilitating subsequent obturation of the canal [2]. Despite their efficacy in achieving apical closure, these methods do not address the continued development of root length or dentinal wall thickness, resulting in structurally compromised teeth that are susceptible to long-term failure [3].

Over the past two decades, regenerative endodontics has emerged as a paradigm shift in the management of immature teeth with necrotic pulp [4]. Regenerative endodontic treatment (RET) is built on the principles of tissue engineering and aims not only to resolve infection but also to restore the natural function of the pulp-dentin complex [5]. By leveraging the body’s intrinsic healing capacity, RET seeks to promote continued root development and strengthen the tooth structure, addressing the limitations of traditional apexification techniques [6].

Key components of RET include:

1. Disinfection: Thorough cleansing of the root canal system using biocompatible irrigants, such as sodium hypochlorite and EDTA, to eliminate pathogens while preserving viable stem cells.
2. Induction of a Scaffold: Creation of a blood clot or insertion of biomaterial scaffolds, such as platelet-rich plasma, to serve as a matrix for cell proliferation and differentiation.
3. Sealing with Biocompatible Materials: Placement of MTA or similar materials to ensure a coronal seal, protecting the regenerated tissue from reinfection.

Advancements in tissue engineering have further enhanced the efficacy of RET. The integration of growth factors, such as bone morphogenetic proteins (BMPs) and transforming growth factor-beta (TGF-β), along with mesenchymal stem cells derived from the apical papilla, has shown promise in promoting regeneration [7]. These innovations underline the potential of RET to not only restore biological vitality but also improve the long-term prognosis of immature teeth [8].

Globally, regenerative endodontics has gained traction as a transformative approach. Clinical studies from diverse populations report favorable outcomes, including the resolution of periapical lesions, thickening of dentinal walls, and apical closure. However, long-term data remain sparse, particularly in resource-constrained settings. Understanding the clinical and radiographic outcomes over extended periods is critical for validating RET as a standard of care and refining its protocols to achieve consistent success [9].

The need for this study is further emphasized by the variability in outcomes reported in existing literature. Factors such as the patient’s age, the extent of apical infection, the disinfection protocol employed, and the presence of mechanical or procedural errors significantly influence success rates. By addressing these variables and assessing outcomes over two years, this study aims to fill existing gaps in knowledge and provide robust evidence supporting the efficacy of regenerative endodontics [10].

This study focuses on evaluating the long-term clinical and radiographic outcomes of regenerative endodontic treatment in immature permanent teeth with necrotic pulp. Through systematic follow-ups at baseline, 6 months, 1 year, and 2 years, it seeks to measure parameters such as root development, periapical healing, and symptom resolution. The findings are expected to advance the understanding of RET’s potential to replace conventional apexification as the gold standard for managing immature permanent teeth.

This prospective observational study was conducted over a period of two years in the Department of Endodontics at a tertiary care dental institution. The primary objective was to evaluate the long-term clinical and radiographic outcomes of regenerative endodontic treatment (RET) in immature permanent teeth with necrotic pulp. The study design was chosen to provide a robust framework for assessing treatment efficacy in a controlled yet clinically relevant setting.

A total of 100 immature permanent teeth from patients aged 8 to 16 years were included in the study. Teeth were selected based on strict inclusion and exclusion criteria. Inclusion criteria mandated the presence of necrotic pulp, evidenced by clinical symptoms such as pain or swelling, and radiographic findings indicating periapical radiolucency, incomplete root development, and an open apex. Patients with systemic conditions such as diabetes or immunosuppressive disorders, prior endodontic treatment on the affected teeth, or severe structural damage to the teeth (e.g., vertical fractures or extensive crown destruction) were excluded to eliminate confounding factors and ensure the reliability of outcomes.

The treatment protocol adhered to established guidelines for RET and was performed by experienced endodontists to maintain consistency across cases. During the first visit, access cavities were prepared under rubber dam isolation to prevent contamination. The canals were irrigated with 1.5% sodium hypochlorite and 17% EDTA, ensuring effective disinfection without compromising viable stem cells in the periapical region. A triple antibiotic paste (TAP), consisting of ciprofloxacin, metronidazole, and minocycline, was introduced into the canals to eliminate residual microbial load. This medicament was sealed in the canal with a temporary restorative material, allowing it to act over a period of 2–3 weeks.

At the second visit, clinical evaluation was conducted to confirm the resolution of symptoms such as pain, swelling, and sinus tract formation. The canals were re-accessed, and irrigation was performed using saline to remove the TAP. A blood clot was induced at the apex using a sterile file, creating a natural scaffold for tissue regeneration. Mineral trioxide aggregate (MTA) was carefully placed over the clot to promote healing and stimulate apical closure. The access cavity was permanently restored with composite resin to ensure a hermetic seal and prevent reinfection.

Follow-up assessments were conducted at 6 months, 1 year, and 2 years to evaluate the long-term success of RET. Clinical success was determined by the absence of pain, swelling, or other signs of inflammation, as well as a lack of tenderness to percussion or palpation. Radiographic success was defined by progressive periapical healing, increased root length, thickening of dentinal walls, and apical closure. Standardized periapical radiographs were taken at each follow-up interval, and quantitative measurements were performed using calibrated digital imaging software to ensure accuracy.

Data collection and analysis followed a structured approach. Descriptive statistics were used to summarize the overall success rates, while paired t-tests were employed to compare root development parameters before and after treatment. Multivariate regression analysis was conducted to identify key predictors of successful outcomes, including patient age, initial size of the periapical lesion, and adherence to the RET protocol. Statistical significance was set at p < 0.05 for all analyses.

Ethical approval for the study was obtained from the institutional ethics committee. Informed consent was secured from all participants or their guardians after explaining the study objectives, procedures, and potential risks. Patients were assured of appropriate retreatment options in the event of treatment failure, ensuring comprehensive care throughout the study.

This comprehensive methodology ensured that the outcomes of RET could be reliably assessed over the long term, providing critical insights into its efficacy as a treatment modality for immature permanent teeth with necrotic pulp.

This study evaluated the long-term clinical and radiographic outcomes of regenerative endodontic treatment (RET) in 100 immature permanent teeth with necrotic pulp. The results are presented in detail, covering clinical success rates, radiographic changes, and factors influencing treatment outcomes.

Table 1 shows the demographic and baseline characteristics of the study population, including patient age, gender, and baseline clinical findings.

Table 1: Baseline Characteristics of Patients and Teeth Treated

Table 2 presents the clinical outcomes of RET at various follow-up intervals.

Table 2: Clinical Success Rates Over Time

Table 3 illustrates the resolution of periapical lesions over time.

Table 3: Radiographic Healing of Periapical Lesions

Table 4 compares root development (length and dentinal wall thickness) before and after treatment.

Table 4: Changes in Root Development

Table 5 highlights the distribution of apical closure at the end of the study period.

Table 5: Apical Closure Status at 2 Years

Table 6 provides data on the relationship between patient age and treatment outcomes.

Table 6: Outcomes by Patient Age

Table 7 explores the correlation between lesion size and radiographic healing.

Table 7: Impact of Lesion Size on Radiographic Healing

Table 8 examines the frequency of complications or adverse events during treatment.

Table 8: Adverse Events During Treatment

Table 9 reports on the relationship between treatment adherence and outcomes.

Table 9: Adherence to Protocol and Success Rates

Table 10 summarizes multivariate regression analysis of factors influencing treatment success.

Table 10: Predictors of Successful Outcomes

The results indicate that regenerative endodontics is highly effective for managing immature permanent teeth, with substantial improvements in clinical and radiographic parameters over two years

This study evaluated the long-term efficacy of regenerative endodontic treatment (RET) in managing immature permanent teeth with necrotic pulp. The findings provide compelling evidence of the clinical and radiographic success of RET, demonstrating its potential as a superior alternative to traditional apexification techniques. By focusing on outcomes such as symptom resolution, periapical healing, root development, and apical closure over a two-year follow-up period, this study contributes to the growing body of evidence supporting the effectiveness of RET.

High Clinical Success Rates

The clinical success rate of 92% observed at the 2-year follow-up underscores the reliability of RET in eliminating symptoms such as pain, swelling, and sinus tract formation. This high success rate aligns with existing studies reporting similar outcomes and reinforces the idea that RET effectively addresses the primary goal of endodontic therapy: the elimination of infection and the preservation of tooth structure. The ability to achieve symptom-free results without relying on traditional obturation methods demonstrates the biological advantage of RET in regenerating pulp-like tissue and restoring vitality [11].

Radiographic Evidence of Healing

Radiographic findings from this study highlight significant improvements in periapical healing and root development following RET. By the 2-year follow-up, 88% of treated teeth exhibited complete resolution of periapical lesions, while 76% demonstrated complete apical closure. These results indicate the remarkable ability of RET to promote biological repair and regeneration. The consistent thickening of dentinal walls and elongation of roots observed in this study further validates RET's ability to restore structural integrity to immature teeth, which is a critical factor in reducing the risk of future fractures [12].

Influence of Age and Lesion Size

The study revealed that younger patients (aged 8–12 years) had higher success rates (95%) compared to older patients (87%), emphasizing the importance of early intervention in cases of immature permanent teeth. This age-related difference may be attributed to the presence of more active stem cells and a robust healing potential in younger individuals. Similarly, smaller periapical lesions were associated with better healing outcomes, highlighting the role of initial lesion size as a predictor of treatment success. These findings underscore the need for timely diagnosis and treatment to maximize the regenerative potential of RET [13].

Importance of Protocol Adherence

Adherence to the RET protocol emerged as a significant factor influencing outcomes. Teeth treated with complete adherence to the standardized protocol showed a success rate of 95%, compared to 85% for cases with partial adherence. This finding reinforces the importance of meticulous procedural steps, including effective canal disinfection, scaffold placement, and proper sealing, to achieve optimal results [14]. The use of triple antibiotic paste and careful induction of a blood clot likely contributed to the high success rates observed in this study.

Comparisons with Traditional Apexification

One of the most notable advantages of RET over traditional apexification is its ability to promote continued root development. In apexification, root development halts after apical closure, leaving the tooth structurally weak. In contrast, RET enables the natural thickening of dentinal walls and elongation of roots, as demonstrated by the significant increases in root length and dentinal wall thickness observed in this study. These findings support the growing consensus that RET offers superior long-term outcomes, particularly in terms of structural integrity and tooth preservation [15].

Limitations and Future Directions

While the results of this study are promising, certain limitations must be acknowledged. The study was conducted at a single institution, which may limit the generalizability of the findings. Additionally, the relatively small sample size of 100 teeth restricts the ability to analyze outcomes across diverse patient populations and clinical scenarios. Future studies should focus on larger, multi-center cohorts to validate these findings and explore the role of emerging techniques, such as the use of growth factors and stem cell-based scaffolds, in enhancing RET outcomes.

Clinical and Public Health Implications

The findings of this study have significant implications for clinical practice and public health. By demonstrating the efficacy of RET in managing immature permanent teeth, this study supports its adoption as the standard of care in endodontics. The biological advantages of RET, combined with its ability to achieve long-term success, make it a highly attractive option for clinicians. Public health initiatives aimed at increasing awareness and accessibility to advanced endodontic treatments, particularly in resource-limited settings, can further enhance the reach and impact of RET [16].

This study highlights the significant potential of regenerative endodontic treatment (RET) as a transformative approach for managing immature permanent teeth with necrotic pulp. Over a two-year follow-up period, RET demonstrated high clinical success rates, with 92% of treated teeth remaining symptom-free and 88% achieving complete resolution of periapical lesions. Radiographic findings further validated the efficacy of RET, with notable increases in root length, thickening of dentinal walls, and apical closure in 76% of cases. These outcomes underscore the ability of RET to restore both function and structural integrity to immature teeth, setting it apart from traditional apexification techniques that lack regenerative capabilities.

The findings of this study also emphasize the critical role of patient age, lesion size, and protocol adherence in determining treatment success. Younger patients exhibited better outcomes, highlighting the importance of early intervention. Complete adherence to the RET protocol, including meticulous disinfection and scaffold placement, emerged as a key determinant of favorable outcomes. These insights provide valuable guidance for clinicians in optimizing RET procedures to maximize success rates.

Compared to conventional apexification, RET offers superior long-term benefits, including enhanced root development and structural reinforcement, which reduce the risk of tooth fracture. This makes RET a highly viable alternative, particularly for younger patients with immature teeth requiring long-term preservation.

However, the study’s limitations, including its single-center design and relatively small sample size, call for further research involving larger and more diverse populations. Future studies exploring the integration of advanced techniques, such as growth factors and stem cell-based therapies, could further enhance the efficacy of RET and establish its role as the gold standard for managing immature permanent teeth.

In conclusion, regenerative endodontics represents a significant advancement in dental science, offering a biologically driven solution that addresses both the functional and structural needs of immature permanent teeth. By adopting RET as a standard treatment modality, clinicians can provide patients with outcomes that not only resolve current pathology but also preserve dental health for the future.

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