Pedo 11: Reaction of the Tooth to Trauma PDF

Pedodontics REACTION OF THE TOOTH TO TRAUMA Lec 11 Dr. Rawaa B. Fadhil B.D.S M.Sc. 5th stage Reaction of the tooth to trauma 1- Pulpal hyperemia  Congestion of blood within the pulp chamber a short time after injury can be detected in clinical examination.  If a strong light is directed on the lab...

Pedodontics REACTION OF THE TOOTH TO TRAUMA Lec 11 Dr. Rawaa B. Fadhil B.D.S M.Sc. 5th stage Reaction of the tooth to trauma 1- Pulpal hyperemia  Congestion of blood within the pulp chamber a short time after injury can be detected in clinical examination.  If a strong light is directed on the labial surface of the injured tooth and the lingual surface is viewed in a mirror, the coronal portion of the tooth will often appear reddish compared with the adjacent teeth.  The color change may be evident for several weeks after the accident and often indicates a poor prognosis. 2. Internal hemorrhage  Hyperemia and increased pressure may cause the rupture of capillaries and the escape of red blood cells, with subsequent breakdown and pigment formation  Theses may be reabsorbed before gaining access to the dentinal tubules, if bleeding is minute (in which case little if any color change will be noticeable and what does appear will be temporary)  In more severe cases there is pigment formation in the dentinal tubules. The change in color is evident within 2 to 3 weeks after the injury, and although the reaction is reversible to a degree, the crown of the injured tooth retains some of the discoloration for an indefinite period. In cases of this type, there is some chance that the pulp will retain its vitality, although the likelihood of vitality is apparently low in primary teeth with darkgray discoloration. 3. Calcific metamorphosis of the dental Pulp (progressive canal calcification Or dystrophic calcification)  partial or complete obliteration of the pulp chamber and canal. Although the radiograph may give the illusion of complete obliteration, an extremely fine root canal and remnants of the pulp will persist  The crowns of teeth that have undergone this reaction may have a yellowish, opaque color  Primary teeth demonstrating calcific metamorphosis will usually undergo normal root resorption  A permanent tooth showing signs of calcific changes as a result of trauma should be regarded as a potential focus of infection must be kept under observation or treated endodontically. 4. Internal resorption  Internal resorption is a destructive process generally believed to be caused by odontoclastic action  It may be observed radiographically in the pulp chamber or canal within a few weeks or months after an injury  The destructive process may progress slowly or rapidly. If progression is rapid, it may cause a perforation of the crown or root within a few weeks  It is described as “pink spot” because when the crown is affected, the vascular tissue of the pulp shines through the remaining thin shell of the tooth. The occurrence referred of a perforation as “perforating hyperplasia of the pulp”  If detected early, the tooth may be retained when endodontic procedures are instituted. 5- Peripheral (external) root resorption  Due to damage to the periodontal structures and the pulp may not become involved. In case of sever trauma with some displacement of the tooth  Gross areas of the root have been destroyed. In exceptional cases the resorption may become arrested, and the tooth may be retained. 6- Pulpal necrosis  A severe blow to a tooth causing displacement often results in pulpal necrosis.  The blow may cause a severance of the apical vessels, in which case the pulp undergoes autolysis and necrosis. In a less severe type of injury, the hyperemia and slowing of blood flow through the pulpal tissue may cause eventual necrosis of the pulp.  In some cases the necrosis may not occur until several months after the injury.  A tooth receiving an injury that causes coronal fracture may have a better pulpal prognosis than a tooth that sustains a severe blow without fracturing the crown. Because of that the energy dissipates as the crown fractures, rather than all of the energy’s being absorbed by the tooth’s supporting tissues.  The tooth with a necrotic pulp should be extracted or treated with RCT  Risk of pulp necrosis (from the lowest) Concussion, subluxation, extrusion, lateral luxation, intrusive luxation – 100% chances of pulp necrosis and external root resoption 7. Ankylosis  A condition caused by injury to the periodontal ligament and subsequent inflammation, which is associated with invasion by osteoclastic cells. The result is irregularly resorbed areas on the peripheral root surface  In histologic sections, repair can be seen that may cause a mechanical lock or fusion between alveolar bone and the root surface  Clinical evidence of ankylosis is seen as a difference in the incisal plane of the ankylosed tooth and adjacent teeth. The adjacent teeth continue to erupt, whereas the ankylosed tooth remains fixed in relation to surrounding structures  The radiograph may show an interruption in the periodontal membrane of the ankylosed tooth, and often the dentin may appear to be continuous with alveolar bone.  The ankylosed anterior primary tooth should be removed if there is evidence of its causing delayed or ectopic eruption of the permanent successor  If ankylosis of a permanent tooth occurs during active eruption, eventually a discrepancy between the position of this tooth and its adjacent ones will be obvious. The uninjured teeth will continue to erupt and may drift, with a loss of arch length. Therefore either surgical repositioning or the removal of a permanent tooth that becomes ankylosed is often necessary, especially if the ankylosis occurs during the preteen or early teen years. Reaction of permanent tooth bud to injury  The close anatomic relationship between the apices of primary teeth and their developing permanent successor explains why injuries to primary teeth may involve permanent dentition  The problem may be noticed several months or years later 1- hypocalcification and hypolpasia  Permanent teeth in humans may show a variety of defects, including gross malformations of the crown. The presence of a small, pigmented hypoplastic area has been referred to as Turner tooth. Small hypoplastic defects may be restored by the resinbonding technique. 2- Reparative dentin production  In cases in which the injury to the developing permanent tooth is severe enough to remove the thin covering of developing enamel or cause destruction of the ameloblasts, the subjacent odontoblasts have been observed to produce a reparative type of dentin.  The irregular dentin bridges the gap where there is no enamel covering to aid in protecting the pulp from further injury. 3- Dilaceration  Tooth with sharp bend in crown or root occurs after the intrusion or displacement of an anterior primary tooth.  Most commonly seen in maxillary permanent incisor  The developed portion of the tooth is twisted or bent on itself, and in this new position growth of the tooth progresses. The crown of a permanent tooth or a portion of it develops at an acute angle to the remainder of the tooth  Dilacerated tooth fails to erupt, or sometimes erupt into an abnormal position Treatment  1- Unerupted dilacerated tooth usually require surgical extraction  2- Erupted teeth with root dilaceration should be extracted, if they are in abnormal position, it is difficult to move by orthodontic force  3- Following extraction, extracted space should be maintained by prosthesis or closed by orthodontic treatment