subgingivally for adequate access. Rapid orthodontic extrusion over 4-6 weeks aiming
to move the root a maximum of 4 mm is the best option. This is achieved by
cementing a 'J' hook made from 0.7-mm stainless steel wire into the canal and using
elastic traction applied over an arch wire cemented between one abutment tooth on
either side of the injured tooth. Retention for one month at the end of movement is
advised to prevent relapse (708HFig. 12.31). If aesthetics are a particular concern then an
orthodontic bracket can be bonded to a temporary crown made over the 'J' hook. The
temporary crown length will need to be reduced as extrusion occurs (709HFig. 12.32 (a)-
(d)).
- Cover the root with a mucoperiosteal flap. This will maintain the height and width
of the arch and will facilitate later placement of a single tooth implant.
INTERNAL SPLINTING
Fractures arising in the coronal and middle third of the root often result in excessive
mobility of the coronal fragment and techniques have been described to internally
splint the coronal and apical portions together with a rigid root filling material.
Internal splints have ranged from hedstroem files to nickel-chromium points, screwed
and cemented into position. These approaches are in effect single cone root filling
procedures, and cannot be relied upon to give a long-term safeguard against the re-
entry of oral micro-organisms to the canal and fracture line. Most are doomed to
failure and other restorative options are preferred.
PULPAL NECROSIS IN ROOT FRACTURE
Pulpal necrosis occurs in about 20% of root fractures and is the main obstacle to
adequate repair. The initial amount of displacement of the coronal portion rather than
the level of the fracture or the presence of an open or closed apex is the most
significant factor in determining future pulpal prognosis. Most cases of necrosis are
diagnosed within 3 months of a root fracture. A persistent negative response to
electric stimulation is usually confirmed on radiography by radiolucencies adjacent to
the fracture line. The apical fragment almost always contains viable pulp tissue and
invariably scleroses. Rarely it may require surgical removal.
In apical and middle third fractures any endodontic treatment is usually confined to
the coronal fragment only. A barrier is achieved on the coronal aspect of the fracture
line by preparation of a stop with non-setting calcium hydroxide or MTA, and the
coronal canal is obturated with gutta percha. After completion of endodontic
treatment, repair and union between the two fragments with connective tissue is a
consistent finding.
In coronal third fractures that develop necrosis either the radicular portion can be
retained (see above), both portions extracted, or the fracture internally splinted (see
above).