The Effect of The Age and Apical Diameter on Regeneration of Pulp Tissue (Clinical Study)

Abstract

Dental trauma and deep carious lesions can often lead to pulpal necrosis in children and young adults. Trauma may result in avulsion, intrusion, extrusion or lateral displacement. Caries may cause bacterial invasion into the young pulp space. Unfortunately, many of these teeth will become necrotic prior to completing root development. Treatment of necrotic permanent immature teeth can present a difficult clinical situation. Extraction and replacement with implants or fixed bridges are often contraindicated due to incomplete skeletal growth. Historically, immature apical development has been managed with root-end closure through apexification. However this procedure presents several challenges.Cleaning, shaping, disinfection and obturation are often challenging in large blunderbuss canal with open apices. Even if apexification closure is successful, it still has thin weak root walls that are susceptible to fracture. An alternative approach to treat the immature necrotic permanent tooth is to regenerate pulpal tissue allowing for continued root formation. In 2004, Drs. Francisco Banchs and Martin Trope(8) demonstrated the advantages of this treatment modality resulting in continued maturation of the entire root versus formation of an apical calcific-barrier through apexification. The advantage of this treatment is continued root lengthening and reinforcement of lateral dentinal walls with deposition of new hard tissue. Revascularization, regeneration and revitalization are commonly used terms to describe the re-growth of vital tissues within the root canal space. The goal is to stimulate restoration of the pulp-dentin complex, leading to deposition of dentin along the root canal walls. The aim of our study was to evaluate the effect of the age and the apical diameter on the success of the regenerative procedures. The cases are divided into 2 groups and 2 subgroups each. Group Isubgroup A has age range from 8 up to 12 years with apical diameter less than 1 mm while group I subgroup B has age range from 8 up to 12 years with apical diameter more than 1 mm while the group II subgroup A has age range from 13 up to 18 years with apical diameter less than 1 mm while the group II subgroup B has age range from 13 up to 18 years with apical diameter greater than 1 mm. The regenerative procedures were done whereaccess was made into the large coronal pulp space. Cleaning and shaping against the canal walls was contraindicated. Gentle irrigation with sodium hypochlorite as antibacterial irrigants then EDTA solution followed by normal saline solution was accomplished, followed by placement of TAP mixture followed by temporary restoration. Two to three weeks are allowed for disinfection and resolution of signs and symptoms. In the second visit,evaluation of the patients was done and asymptomatic patients with asymptomatic teeth are subjected to gentle flushing of the TAPwith warm saline solution then laceration of apical tissues with an endodontic file to induce intracanal bleeding and the placement of an appropriate subcoronal collagen matrixagainst which a MTA plug can be placed. Permanent coronal access closure is then achieved. These patients were followed and follow up was made in 3 months interval (ie at 3,6,9 and12 months). The results showed that there was significance difference between groups in relation to the change in the age of the patients selected where the younger age provide the greater decrease in the apical diameter and the greater increase in the root length. Alsoin relation to the apical diameter, the groupswith greater apical diameter showed greater decrease in the apical diameter and greater increase in the root thickness than the remaining groups.