Hyperbaric oxygen: a means of decreasing ischemic epiphyseal damage in a pediatric rabbit model.

The effect of hyperbaric oxygen on epiphyseal ischemia was evaluated using a pediatric rabbit model. Forty-five animals were compared in this study: 23 from a control pilot study and 22 hyperbaric exposed animals. In each animal the right distal femoral and proximal tibial epiphyses were isolated on a popliteal vascular pedicle. The left leg acted as the control. The growth difference between the rabbit's hindlimbs was the means of comparison throughout the groups established. Warm ischemia was induced by applying a vascular clamp to the right popliteal artery for 12 hours (20 animals) and 7 hours (17 animals). The remaining 8 animals underwent a sham operation without interruption of epiphyseal perfusion. On completion of the ischemic period hyperbaric oxygen therapy (HBOT) was performed on 12 12-hour (12h-HBOT) and 10 7-hour (7h-HBOT) animals at 2 atmospheres for 90 minutes twice per day for 4 postoperative days. The animals were killed on either postoperative day 14 or 90. Measurement of longitudinal bone growth was performed on the 90-day animals from serial radiographs at the time of surgery and then at 1 month, 2 months, and 3 months after surgery. There was no significant difference in longitudinal bone growth between the sham-operated and the 7h-HBOT animals at 1, 2, and 3 months. There was a statistically significant difference, however, between the normal growth of the 7h-HBOT group compared with the abnormal growth of the 7-hour, 12-hour, and 12h-HBOT animals. Histology was consistent, with the bone growth data demonstrating relative normalcy of the 7h-HBOT group epiphyseal plates versus severe architectural aberrance and necrosis of the 12h-HBOT group epiphyses. Our experimental data indicate that a clinical trial should be instituted using HBO for pediatric replantation patients when warm ischemia exceeds 7 hours. (J Hand Surg 2000; 25A:159-165.

A systematic approach to the sampling of dental DNA.

As investigations into the forensic aspects of DNA analysis continue, the human tooth will play a dual role in identification. Dentin and enamel provide a protective enclosure for genomic and mitochondrial DNA as well as providing the basis for radiographic, biochemical, and ultrastructural forensic studies. The purpose of this investigation is to establish technical guidelines, based on histology and experimental evidence, for the management and sampling of dental DNA. The anatomic location of dental DNA is discussed with emphasis on the conservation of tooth structure during sampling. Ten pairs of maxillary right and left third molars were sampled for DNA following storage for 18 weeks at ambient temperature and humidity. Right third molars were crushed, whereas the left third molars were sectioned conservatively prior to sampling the DNA. The quantity and quality of human DNA obtained from each tooth was compared, as well as the radiographic appearance of remaining hard tissue and the overall simplicity of each approach. DNA typing was performed, both sequence and length based analyses, comparing teeth from the same individual and teeth from different donors. The results of this study suggest that the odontologist will maximize the dental DNA yield by crushing the entire specimen but that substantial yields of human DNA can be obtained by using a conservative technique that preserves the tooth structure. In addition, the method of sampling does not affect the ability to perform DNA typing analyses.

Utilization of an oral pathology service: a professional responsibility.

The role of oral pathologists as members of the comprehensive health care team is reviewed. The importance of utilizing an Oral Pathology Service in the everyday practice of dentistry and medicine and the inherent medicolegal considerations are discussed. Standards of care for submission of surgically removed oral tissues is an issue that warrants further delineation.

Malignant cyst of the lateral aspect of the neck: branchial cleft carcinoma or metastasis?

A 58-year-old man had a left jugulodigastric mass, which was found to be cystic by computed tomography, and no evidence of other lesions. Grossly and histologically, the surgical specimen consisted of a thin-walled, fluid-filled cyst lined by squamous epithelium that varied in appearance from benign to invasive squamous cell carcinoma. The findings supported a differential diagnosis of branchial cleft carcinoma (BCCA) versus cystic growth of a lymph node metastasis from an occult malignancy. On this basis, guided biopsies of the upper aerodigestive tract were performed, with strong suspicion of a tonsillar bed lesion. Microscopic examination revealed the primary tumor within tissue excised from the left tonsillar fossa. Comparison of the current case with cases of BCCA and cystic tonsillar metastases from the literature illustrated the potential pitfalls in rendering a diagnosis of BCCA. Recognition of this lesion as a distinctive clinical variant of oropharyngeal carcinoma is warranted.

Asymptomatic periapical radiolucent lesion found in an area of previous trauma.

The case of an anterior mandibular radiolucent area, which unexpectedly yielded salivary gland tissue, is described. Salivary gland depressions in the posterior mandible are readily recognized because of their almost pathognomonic radiographic appearance. A salivary gland inclusion in the anterior mandible in the proximity of teeth may create a diagnostic dilemma where superimposed periapical pathosis is present. The clinical importance lies in the recognition and appropriate treatment of the lesion. For the anterior salivary gland inclusion, a biopsy and a microscopic examination provide the most reliable diagnosis.

Well-circumscribed mixed-density lesion coronal to an unerupted permanent tooth.

The case reported is that of an ameloblastic fibro-odontoma in an 11-year-old male. The radiographic and clinical findings were typical, appearing as a well-defined radiolucent-radiopaque lesion coronal to an erupting permanent tooth. Treatment consisted of surgical removal (enucleation) of the hard and soft tissue mass. Recurrence of the lesion is not anticipated.

Nonpainful, smooth-surfaced, bluish nodule on the upper lip.

A case of a vascular leiomyoma of the upper lip has been presented. A review of the literature was completed, and the findings reported. Leiomyomas are rare intraoral neoplasms. When affecting the mouth, they are most likely to occur on the tongue, palate, buccal tissues, and lips. Conservative local excision is the recommended treatment.

Pyoderma gangrenosum involving the head and neck.

Pyoderma gangrenosum (PG) is a rare pathergy associated with systemic diseases such as ulcerative colitis and polycythemia vera. Its recognition in the differential diagnosis of other ulcerative lesions is important in managing an affected patient. A patient who developed lower extremity, oral, and cervical manifestations of this disease on separate occasions is presented. It is imperative that every clinician be aware of this entity because of the potential untoward effects of delayed or improper treatment including unnecessary surgery. Systemic and intralesional steroids are the treatment of choice.

Multiple asymptomatic yellowish-white nodules on the free gingiva.

Gingival plane xanthomas are unusual oral presentations of hyperlipidemia and they may be of minimal clinical significance to the patient because they are asymptomatic. However, the presence of gingival xanthomas should be considered as a possible precursor of an underlying life-threatening disease process. Many of these systemic conditions may severely compromise dental therapy; they include atherosclerotic coronary disease, peripheral vascular disease, diabetes mellitus, biliary cirrhosis, multiple myelomas, leukemia, and hyperthyroidism. Clinicians should be aware of this association and its important implications.

Early aggressive cemento-ossifying fibroma: a diagnostic and treatment dilemma.

A case involving a 22-year-old male patient with early aggressive cemento-ossifying fibroma in the mandible is discussed. The historical difficulty in categorizing fibro-osseous lesions is reviewed, and the importance of clinical, radiographic, and surgical findings to the ultimate diagnosis and correct treatment of these lesions is emphasized.

Multiple, shallow, circinate mucosal erosions on the soft palate and base of uvula.

Stomatitis areata migrans is an uncommon oral disease that may affect mucous membranes other than the tongue or be concomitant with geographic tongue. The clinical appearance emulates geographic tongue at an ectopic site, and the lesions rarely are symptomatic.

Stomatitis areata migrans affecting the gingiva.

A 62-year-old male patient with a varied medical history and oral lesions consistent with stomatitis areata migrans is discussed. The stomatitis areata migrans affected essentially all oral soft tissues, including rarely involved gingival tissues. Clinical and histologic documentation of the gingival involvement is presented.

Triangular-shaped radiolucent area between roots of the mandibular right canine and first premolar.

The squamous odontogenic tumor is a rare odontogenic neoplasm occurring primarily in the anterior maxilla and posterior mandible. The clinical presentation is that of tooth mobility with a semicircular or triangular, well-defined radiolucent area. Histologic features include dense fibrous connective stroma with scattered islands of bland epithelium exhibiting no ameloblastomatous features. Conservative surgical treatment in most cases is sufficient; however, lesions in the maxilla may require more extensive surgical procedures to ensure resolution.

Evaluation of 5-fluorouracil in the treatment of actinic keratosis of the lip.

Topically applied 5-fluorouracil has recently gained acceptance in the treatment of actinic keratosis of the lip; however, histologic evidence confirming the effectiveness of the therapy has not yet been established. Pretreatment biopsies were performed on six patients to confirm actinic damage and grade the degree of dysplasia. After 5-fluorouracil therapy, biopsies of tissue adjacent to the previous biopsy sites were performed to determine the success of treatment. Histologic evaluation showed residual dysplasia in all posttreatment biopsy material, even though the clinical stigmata of the actinic lesions had been improved or eliminated.