Management of Tooth Resorption by Using Calcium Hydroxide : A Case Report

In this case report, the treatment of internal root resorption in a 24 years-old male was done by using nonsurgical root canal therapy and the clinical outcome was evaluated. Both the maxillary central incisors were examined clinico-radiographically. On clinical examination, the maxillary incisors were found discolored. Radiographic examination revealed a punched-out radiolucent lesion on the cervical area of pulpal canal of both of the teeth and periradicular radiolucency was also evident. Conservative non-surgical root canal treatment was performed with long term calcium-hydroxide therapy. Following eight months of the treatment, the resorption process was stopped and a calcific bridge was formed at the apex of the roots indicated the evidence of recalcification. Conventional root canal obturation method was implied followed by clinical and radiological evaluation for next two years.


Introduction:
Resorption of root is one of the reasons for loss of the tooth at an early age and it is a major concern in endodontic therapy. 1 The enamel, dentine and cementum of permanent teeth do not normally undergo resorption. 2 When resorption of permanent teeth is observed clinically, the resorption is usually due to the result of trauma; chronic inflammation of the pulp or periodontal tissues, or both; or induced pressure in the periodontal ligament associated with orthodontic tooth movement, tumors, or tooth eruption. 3lpal inflammation initiates internal resorption followed by disappearance of the odontoblasts and pre-dentin, and a pulpal invasion of macrophage-like resorbing cells. 4,5he signs and symptoms of this pathologic condition remain asymptomatic unless it is detected on radiographic screening.Frequently, it is observed in the cervical region but may occur in all areas of the root canal system. 3When the resorption occurs in coronal region it is usually appears as pink spot.The reason is that the prolific capillaries in the pulpal inflammatory (granulomatous) tissue resorbing the coronal dentin and enamel. 6In external resorption, a change in the natural balance between osteoblastic and osteoclastic action in the periodontal ligament occurs which removes dentine from the root surface.This process of tooth resorption involves an elaborate interaction among inflammatory cells, resorbing cells, and hard tissue structures. 7 the cases of tooth trauma, the internal pulpal hemorrhage can develop.Formed blood clots are then organized and replaced by granulation tissue which compresses dentin wall of the pulpal chamber or root canal.With activation of undifferentiated mesechymal cells of the pulpal tissue they differentiate into dentinoclasts, which is said to be responsible for resorption of the hard tooth structure 8 .[11] If root resorption remains untreated, it usually leads to perforation of the tooth root followed by tooth fracture 1 .Surgical correction and filling of the communication with restorative materials has been suggested in cases of large defects. 124][15] The procedure included tooth trepanation, the removal of residual vital pulp tissue and newly developed granular tissue and application of either Calcium hydroxide (Ca(OH) 2 ),Mineral Trioxide Aggregate (MTA), calcium phosphate cement (CPA) or hydroxyapatite. 1 this case study, internal root resorption in a 24 years male was treated by non-surgical root canal therapy and the clinical as well as radiological outcome was evaluated.

Discussion:
In the present study, Ca(OH) 2 in paste form was applied with the help of lentulo-spiral instrument after complete debridement of the canals.At six months of Ca (OH) 2 application there was no evidence of further resorption and calcific bridge was formed at eight months.Ca(OH) 2 worked by its high alkaline pH to create an antibacterial environment and it also causes irritation to the surrounding tissues that had stimulated pulpal defense and repair. 16he periradicular area, where the Ca(OH) 2 paste can cause stimulatory effect on the undifferentiated mesenchymal cells to transform into cementobalst. 17,18The cementoblasts and periodontal ligaments slowly resurface the damaged root and even closed minor foramina that no longer contain neurovascular bundles. 18In the follow-up visits up to three years, no radiographic and clinical evidence of further root resorption was observed and the teeth were in function.
Many previous studies have reported that internal resorption can be managed by non-surgical and surgical methods.Ingle et al. and others made a case for the wider use of Ca(OH) 2 as a stimulating and healing agent . 1 Nowa-days these thoughts become a reality i.e.[21] The advantages of Ca(OH) 2 include elimination of surviving bacteriae when used as intracanal medicament 22 and arresting inflammatory root resorption as well as stimulation of healing in treating resorption. 23 the present study, the mechanism of Ca(OH) 2 to heal internal resorption is not clearly understood.However previous studies indicated that the hydroxyl group of Ca(OH) 2 provides an alkaline environment which encourages repair and active calcification.The alkaline pH neutralizes lactic acid that is released from the osteoclasts and thus prevent a dissolution of the mineral components of dentine.Additionally, alkaline pH activates alkaline phosphatase for tissue formation. 23Following wellexecuted treatment, wherein infection and irritation are terminated, cementoblasts and periodontal ligament slowly resurfaced the damaged root and close the minor foramina 24 which in turn provides protection against further infection.
Based on the present study and together with the previous studies, it can be stated that the teeth were saved successfully only by non-surgical endodontic treatment.(h) (i) (j) (k) Case report:A 24 years old patient reported to the Dept. of Conservative Dentistry and Endodontics, BSMMU with the complaint of intermitent pus discharge through labial mucosa of maxillary incisors for last two years.The patient gave the history of trauma five years back.The patient felt no significant pain during the whole period but gave the history of occasional swelling and release of exudates on pressure.Slight discoloration of the affected teeth was noticed during clinical examination but no pink spot was identified.However, the left central incisor was extruded 1mm in relation to the right one [Figure-1(a)].A sign of sinus tract through the periodontal pocket of right maxillary incisor was present.There was mild pain on percussion on both of the teeth.Pulp vitality tests, ethyl chloride spray for cold sensation and warm gutta percha stick for hot sensation, were negative.Radiographic findings revealed that an oval shaped enlargement of root canal space having a smooth margin where pulp chamber was more radiolucent than other non-resorptive area of the pulp canal.In the apical area there was radiolucency and irregular root outline especially at the right maxillary central incisor revealed external root resorption along with bone resorption [Figure-1(b)].The initial treatment plan included the removal of all necrotic tissues and microorganisms by vigorous cleaning by using 5.25% sodium hypochlorite solution and shaping of the canals after, determining the working length [Figure-1(c)].Then the canals were fully prepared with 60 number of H-file and the canal made dry.Then it was filled with radio-opaque Ca (OH) 2 up to apical region by lentulo spiral instrument [Figure-2(d)].During follow up after three months the patient had no complain of discharge of exudates [Figure-2(e)] and the same was evident at six months follow-up period [Figure-2(f)].

Fig. - 3 :
Fig. -3: Follow up radiographic view of the same teeth just after root canal obturation (h), at 6 months interval (i), at 12 months interval (j) and at 24 months interval (k).