Histologic study of a human immature permanent premolar with chronic apical abscess after revascularization/revitalization

Clinical and radiographic outcomes of traumatized immature permanent necrotic teeth after revascularization/revitalization therapy

INTRODUCTION

Revascularization treatment is rapidly becoming an accepted treatment alternative for the management of endodontic pathology in immature permanent teeth with necrotic dental pulps. However, the success and timing of clinical resolution of symptoms, and radiographic outcomes of interest, such as continued hard tissue deposition within the root, are largely unknown.

METHODS

In this prospective cohort study, 20 teeth were treated with a standardized revascularization treatment protocol and monitored for clinical and radiographic changes for 1 year. Standardized radiographs were collected at regular intervals, and radiographic changes were quantified.

RESULTS

All 20 treated teeth survived during the 12-month follow-up period, and all 20 also met the clinical criteria for success at 12 months. As a group, the treated teeth showed a statistically significant increase in radiographic root width and length and a decrease in apical diameter, although the changes in many cases were quite small (such that the clinical significance is unclear). The within-case percent change in apical diameter after 3 months was 16% and had increased to 79% by 12 months, with 55% (11/20) showing complete apical closure. The within-case percent change in root length averaged less than 1% at 3 months and increased to 5% at 12 months. The within-case percent change in root thickness averaged 3% at 3 months and 21% at 12 months.

CONCLUSIONS

Although clinical success was highly predictable with this procedure, clinically meaningful radiographic root thickening and lengthening are less predictable after 1-year of follow-up. Apical closure is the most consistent radiographic finding.

Treatment of a large cystlike inflammatory periapical lesion associated with mature necrotic teeth using regenerative endodontic therapy

INTRODUCTION

Regenerative endodontic therapy is currently used to treat immature permanent teeth with necrotic pulp and/or apical periodontitis. However, mature teeth with necrotic pulp and apical periodontitis have also been treated using regenerative endodontic therapy. The treatment resulted in resolution of apical periodontitis, regression of clinical signs and symptoms but no apparent thickening of the canal walls, and/or continued root development. A recent study in an animal model showed that the tissues formed in the canals of mature teeth with apical periodontitis after regenerative endodontic therapy were cementumlike, bonelike, and periodontal ligament-like tissue with numerous blood vessels. These tissues are similar to the tissues observed in immature permanent teeth with apical periodontitis after regenerative endodontic therapy.

METHODS

A 23-year-old woman had a history of traumatic injury to her upper anterior teeth when she was 8 years old. Subsequently, #8 developed pulp necrosis and an acute apical abscess and #7 symptomatic apical periodontitis. The apex of #8 was slightly open, and the apex of #7 was completely formed. Instead of nonsurgical root canal therapy, regenerative endodontic therapy was attempted, including complete chemomechanical debridement on #8 and #7. This was based on the premise that filling of disinfected root canals with the host's biological vital tissue might be better than filling with foreign materials.

RESULTS

After regenerative endodontic therapy of #8 and #7, there was radiographic evidence of periapical osseous healing and regression of clinical signs and symptoms. The pulp cavity of #8 decreased in size, and the apex closed. The pulp cavity of #7 appeared to be obliterated by mineralized tissue. These indicated ingrowth of new vital tissue into the chemomechanically debrided canals.

CONCLUSIONS

Regenerative endodontic therapy of mature teeth with apical periodontitis and apical abscess can result in the regression of clinical signs and/or symptoms and healing of apical periodontitis but no apparent thickening of the canal walls or continued root development. Filling of the disinfected canals with the host's vital tissue may be better than with foreign materials because vital tissue has innate and adaptive immune defense mechanisms.

Radiographic and clinical outcomes of the treatment of immature permanent teeth by revascularization or apexification: a pilot retrospective cohort study

INTRODUCTION

This retrospective cohort study compared clinical and radiographic outcomes of endodontic treatment performed in immature nonvital permanent teeth by apexification (calcium hydroxide or apical barrier with mineral trioxide aggregate) versus revascularization.

METHODS

A comprehensive chart review was performed to obtain a cohort of previously completed cases with recalls. Clinical and radiographic data were collected for 31 treated teeth (19 revascularization and 12 apexification) with an average follow-up time of 17 months and a recall rate of 63%. Tooth survival, success rate, and adverse events were analyzed. Changes in radiographic root length, width, and area were quantified.

RESULTS

The majority of treated teeth survived throughout the study period, with 30 of 31 (97%) teeth surviving (18/19 [95%] revascularization and 12/12 apexification). Most cases were also clinically successful, with 27 of 31 (87%) meeting criteria for success (15/19 [78%] revascularization and 12/12 apexification; nonsignificant difference). A greater incidence of adverse events was observed in the revascularization group (8/19 [42%] vs 1/12 [11%] in apexification) (risk ratio = 5.1; P = .04; 95% confidence interval, 0.719-35.48). Although more revascularization cases than apexification cases showed an increase in radiographic root area and width, the effect was not statistically significant.

CONCLUSIONS

In this study, revascularization was not superior to other apexification techniques in either clinical or radiographic outcomes. Studies with large subject cohorts and long follow-up periods are needed to evaluate outcomes of revascularization and apexification while accounting for important covariants relevant to clinical success.

Pulp revascularization in immature permanent tooth with apical periodontitis using mineral trioxide aggregate

Mineral trioxide aggregate (MTA) is a material that has been used worldwide in several clinical applications, such as apical barriers in teeth with immature apices, repair of root perforations, root-end filling, pulp capping, and pulpotomy. The purpose of this case report was to describe successful revascularization treatment of an immature mandibular right second premolar with apical periodontitis in a 9-year-old female patient. After preparing an access cavity without anesthesia, the tooth was isolated using a rubber dam and accessed. The canal was gently debrided using 5% sodium hypochlorite (NaOCl) and 3% hydrogen peroxide irrigant. And then MTA was packed into the canal. X-ray photographic examination showed the dentin bridge 5 months after the revascularization procedure. Thickening of the canal wall and complete apical closure were confirmed 10 months after the treatment. In this case, MTA showed clinical and radiographic success at revascularization treatment in immature permanent tooth. The successful outcome of this case suggests that MTA is reliable and effective for endodontic treatment in the pediatric dentistry.