Tooth resorption part I - pathogenesis and case series of internal resorption
A 27-year-old male patient with a non-contributory medical history presented with a palatal swelling in relation to teeth #9 and 10, which were discolored. Patient reported trauma to the teeth about 12 years back. A large radiolucency was evident on a periapical radiograph relative to the apices of teeth #9 and 10. The apices of the teeth showed irregular ragged edges with loss of lamina dura. The pulp canal space of tooth #9 appeared enlarged and exhibited the presence of a less radiopaque material partially obscuring the continuity of the canal space while tooth #10 displayed total obliteration of the canal space []. A diagnosis of internal replacement resorption along with external inflammatory resorption was made.\nFollowing access cavity preparation, canal space of tooth #9 was negotiated and the radiograph revealed the deviation of the file towards the mesial aspect []. Cleaning and shaping of the canal was performed using hand K-files along with 5.25% NaOCl irrigation followed by placement of Ca(OH)2 intracanal medicament into the canal space. But a periapical radiograph displayed an uneven flow of the intracanal medicament, confirming the presence of metaplatic tissue []. Hence, the Ca(OH)2 was flushed out of the canal and the metaplastic tissue was scrapped off the canal with the aid of hand H-files [] providing an unhindered flow of the medicament [], which was refreshed at regular intervals of 15 days. Pulp canal space of tooth #10 was negotiated at a later appointment and the endodontic therapy of both the teeth was completed in next few scheduled visits []. Further follow-up of the patient could not be done due to relocation to a different state.\nThis type of resorption results from a low-grade irritation of pulpal tissues such as chronic irreversible pulpitis or partial necrosis that is usually localized to a small area of the root canal system.[] The resorption process starts once the odontoblast layer and predentin are disrupted.[] Metaplastic tissue could resemble bone or cementum.[] Though teeth with internal replacement resorption displaying metaplastic changes often present a challenge to the clinician, management is not always impossible. Careful negotiation of the pulp canal space will usually reveal narrow pathways in between the metaplatic tissue, which usually lead to the apical foramen. Rarely will cul de sacs be encountered. The canal can then be enlarged using hand K- files, taking care to apply less pressure towards the canal wall to avoid thinning of the wall. Once the canal is sufficiently widened a stiff H-file (e.g. No.35/40) can be used in a push-pull motion to scrap the metaplastic tissue off the canal. It is in the opinion of the authors that use of Nickel Titanium rotary files is questionable for such cases as the metaplastic tissue may present varied intricacies that may prove detrimental to the files. They probably could be used only after sufficiently enlarging the canal with hand files and after ensuring a smooth glide path.