The pulp is still alive, but the introduction of bacteria into the pulp will not allow the pulp to heal and it will ultimately result in necrosis, or death, of the pulp tissue.Symptoms associated with irreversible pulpitis may include dull aching, pain from hot or cold (though cold may actually provide relief) lingering pain after removal of a stimulus, spontaneous pain, or referred pain.Clinical signs may include reduced response to electronic pulp testing and painful response to thermal stimuli. Today electronic pulp testers are rarely used for diagnosis of the reversibility of pulpitis due to their unreliable nature. Instead they should only be used to test the vitality of teeth. The pulp of a tooth with irreversible pulpitis may not be left alone to heal. That is at least the general viewpoint of the dental profession, and not every dentist would agree that a dead tooth must be treated. No statistics are known but it is possible to have a trouble-free tooth after irreversible pulpitis, albeit a dead tooth. The tooth may be endodontically treated whereby the pulp is removed and replaced by gutta percha. An alternative is extraction of the tooth. This may be required if there is insufficient coronal tissue remaining for restoration once the root canal therapy has been completed. References


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Sabinas brittle hair syndrome, also called Sabinas syndrome or brittle hair-mental deficit syndrome, is an autosomal recessive congenital disorder affecting the integumentary system. Signs and symptoms
Symptoms include brittle hair, mild mental retardation and nail dysplasia. The syndrome was first observed in Sabinas, a small community in northern Mexico. The principal biochemical features of the illness are reduced hair cystine levels, increased copper/zinc ratio, and presence of arginosuccinic acid in the blood and urine.The key finding is brittle hair with low sulfur content, but alternating dark and light bands under polarizing microscopy, trichoschisis, and absent or defective cuticle are additional important clues for the diagnosis of trichothiodystrophy. Review of literature reveals extensive associated findings in trichothiodystrophy. Amino acid analyses of control hair when compared with those of patients with the Sabinas syndrome showed very striking differences with regard to content of sulphur amino acids. As in previous descriptions of amino acid abnormalities in the trichorrhexis nodosa of arginosuccinicaciduria, there were increases in lysine, aspartic acid, alanine, leucine, isoleucine, and tyrosine. Trichothiodystrophy represents a central pathologic feature of a specific hair dysplasia associated with several disorders in organs derived from ectoderm and neuroectoderm. Trichothiodystrophy or TTD is a heterogeneous group of autosomal recessive disorders, characterized by abnormally sulfur deficient brittle hair and accompanied by ichthyosis and other manifestations. Patients with trichothiodystrophy should have a thorough evaluation for other associated manifestations, including investigation of photosensitivity and DNA repair defects.