Comparative outcome of revascularization in bilateral, non-vital, immature maxillary anterior teeth supplemented with or without platelet rich plasma: A case series
A healthy 10-year-old boy was referred for evaluation and management of his broken upper anterior teeth, subsequent to a fall 3-year prior. Root canal therapy was initiated, but not completed by a general dental practitioner. Intraoral examination revealed Ellis class III fracture and a well-defined, localized swelling in relation to both the upper central incisors. Radiographic examination showed immature open apices with thin dentinal walls in relation to both the teeth []. Based on clinical and radiographic examination, a diagnosis of acute periapical abscess in relation to both the central incisor was established. Taking into consideration the stage of root development, the maturation of the dentinal walls and the wide-open apices, revascularization procedure with and without PRP was planned. The risks, complications and possible outcome of this treatment were explained and parental informed consent was obtained.\nTeeth were isolated under rubber dam and re-accessed with a round diamond and an endo-Z bur (Dentsply Maillefer, Tulsa, OK). Purulent discharge was observed in both the teeth. The canals were copiously irrigated with normal saline. Working length was established with a paper point (Dentsply Maillefer, Tulsa, OK) and confirmed radiographically by placing a large file in the canal. Minimal mechanical instrumentation with an International Organization for Standardization number 60H-file (Dentsply Maillefer, Tulsa, OK) and irrigation with 20 mL 2.5% sodium hypochlorite (NaOCl, Cmident, India) was performed. The canal was dried with paper points and an inter-appointment medication of triple antibiotic paste (as per the protocol mentioned by Hoshino et al. 1996) was applied with a sterile number 30 hand lentulo spiral (Dentsply Maillefer, Tulsa, OK). Teeth were temporarily restored with intermediate restorative material (Caulk Dentsply, Milford, DE). This was the chemo-mechanical and disinfection protocol followed for all cases. However, in cases of weeping canals, another inter-appointment dressing was given until the tooth was symptom-free and the canal was dry. Patients were recalled after 4-week. Teeth were re-accessed under rubber dam and revascularization with and without PRP were randomly induced in upper left and right central incisors respectively [].\nLocal anesthetic solution without adrenaline (LOX 2% Neon Lab, India) was infiltrated around the apices of both the central incisors. A sterile endodontic file with a rubber stopper set at 2 mm beyond the established working length was taken. With sharp, fine strokes, the file was pushed past the confines of the canal into the periapical tissue. When frank bleeding was evident, a dry cotton pellet was inserted 3-4 mm into the canal and held there for 5-7 min to allow blood clot formation in the apical third. This revascularization protocol was followed for both the teeth.\nPRP preparation was carried out in a simple, table top laboratory centrifugation machine (Remi model no. — R–8C, India). A total volume of 8.5 mL of whole blood was drawn by venipuncture of antecubital vein. It was then collected in a 10-mL sterile glass tube coated with an anticoagulant (acid citrate dextrose). Whole blood was initially centrifuged (soft spin at 2400 rpm for 10 min) to separate PRP and platelet-poor plasma (PPP) portions from the red blood cell fraction. PRP and PPP portions were again centrifuged (hard spin at 3600 rpm for 15 min) to separate the PRP from the PPP.\nIntra-canal bleeding was induced as described above. Freshly prepared PRP, soaked on a 1 mm2 × 1 mm2 sterile collagen sponge (Metrogene, Septodont, France) was introduced into the root canal of maxillary left central incisor with cotton pliers and carried to the middle third with a size 30 finger plugger (Sybronendo, CA, USA). Access openings were restored with resin modified glass ionomer cement (Photac-Fill, 3MESPE, Minnesota). Standardized intraoral periapical baseline and subsequent follow-up radiographs at 6 and 12 months were taken with a Rinn positioning device (Dentsply, Elgin, IL).