Biomedical subjects

William M Carpenter

Publications and source records attributed to William M Carpenter.

6 recordsLinked to original sources

PubMed2006

Relative frequency of central odontogenic tumors: a study of 1,088 cases from Northern California and comparison to studies from other parts of the world.

PURPOSE: To determine the relative frequency of central odontogenic tumors in relation to all biopsy specimens and to one another in an oral pathology biopsy service and to compare the data with previous studies from different parts of the world. METHODS: Files from the Pacific Oral Pathology Laboratory of the University of the Pacific, San Francisco, CA served as a source of material for this study. Files were systematically searched for all cases of central (intraosseous) odontogenic tumors during a 20-year period. RESULTS: Central odontogenic tumors were identified in 1,088 (1.2%) cases out of the 91,178 accessed. Individually, of all odontogenic tumors, 75.9% were odontomas. The prevalence of the remaining tumors appears to be a rare occurrence. The second most common was ameloblastoma (11.7%), followed by odontogenic myxoma (2.2%). Odontomas are considered hamartomas or developmental anomalies. When excluded from the list of individual odontogenic tumors, ameloblastoma is the most common (48.5%), followed by odontogenic myxoma (9.2%), adenomatoid odontogenic tumor (7.3%), ameloblastic fibro-odontoma (7.3%), ameloblastic fibroma (6.5%), calcifying odontogenic cyst (6.5%), and odontogenic fibroma (6.1%). Each remaining tumor comprises less than 4%. CONCLUSIONS: Studies related to the relative frequency of individual odontogenic tumors from different parts of the world are difficult to compare because most studies are outdated, the list of tumors is limited, and new entities are not included. To determine the real relative frequency, further studies should be conducted, especially in Western societies, by experienced pathologists in the field of odontogenic tumors.

Adolescent↗

PubMed2006

Relative frequency of peripheral odontogenic tumors: a study of 45 new cases and comparison with studies from the literature.

BACKGROUND: Peripheral (extraosseous) odontogenic tumors are rare, and reports in the literature have mainly been single case reports or a small series of cases. The aim of this study was to determine the relative frequency of peripheral (extraosseous) odontogenic tumors relative to one another and relative to their central (intraosseous) counterparts in an oral pathology biopsy service and to compare these data with information available in the literature. METHODS: The files of the Pacific Oral and Maxillofacial Pathology Laboratory of the University of the Pacific, San Francisco, CA, USA, served as the source of material for this study. Files were systematically searched for all cases of peripheral odontogenic tumors (POTs) during a 20-year-period. RESULTS: There were 91,178 cases accessed in which central and POTs were identified in 1,133 (1.24%), central tumors in 1,088 (1.2%), and peripheral tumors in 45 (0.05%). Peripheral tumors accounted for 4% of all 1133 central and POTs. Peripheral odontogenic fibroma (PODF) was the most common of the 45 POTs accounting for 51.1% (23 cases) followed by peripheral ameloblastoma (PA) 28.9% (13 cases) and peripheral calcifying cystic odontogenic tumor (PCCOT) 13.3% (six cases). Peripheral calcifying epithelial odontogenic tumor, peripheral ameloblastic fibroma, and peripheral ameloblastic carcinoma were also identified--each comprised 2.2% (one case each). PODF was more common than its central counterpart by a 1.4:1 ratio. This was the only peripheral tumor that was more common than its central counterpart. PA accounted for 9.3% of all ameloblastomas and PCCOT for 26% of all calcifying cystic odontogenic tumors. CONCLUSION: There is only scarce information in the literature on the relative frequency of POTs. Additional studies should be conducted to determine the true relative frequency. To ensure accuracy, pathologists with experience in the field of odontogenic tumors should conduct these studies. Intraosseous tumors that perforate through the bone to the gingival tissue, clinically presenting as 'peripheral tumors' should be excluded.

Adolescent↗

PubMed2002

Selective ablation of surface enamel caries with a pulsed Nd:YAG dental laser.

BACKGROUND AND OBJECTIVE: High intensity infrared light from the pulsed Nd:YAG dental laser is absorbed by carious enamel and not absorbed by healthy enamel. Consequently, this system has potential for selective removal of surface enamel caries. Safety and efficacy of the clinical procedure was evaluated in two sets of clinical trials at three dental schools. Selective ablation was evaluated with FTIR spectroscopy. STUDY DESIGN/MATERIALS AND METHODS: Carious lesions were randomized to drill or laser treatment. Pulp diagnosis, enamel surface condition, preparations, and restorations were evaluated by blinded evaluators. In Study I, surface caries were removed from 104 third molars scheduled for extraction. One-week post-treatment teeth were evaluated clinically, extracted, and the pulp was examined histologically. In Study II, 90 patients with 462 lesions on 374 teeth were randomized to laser or drill and followed for 6 months. RESULTS: Pulsed Nd:YAG laser removal of surface enamel caries was demonstrated to be both safe and effective. Caries were removed in all conditions. There were no adverse events and both clinical and histological evaluations of pulp vitality showed no abnormalities. A significantly greater number of preparations in the drill groups vs. laser groups entered dentin (drill = 11, laser = 1, P = 0.007). CONCLUSION: The more conservative laser treatment removed the caries but not the sound enamel below the lesion. The pulsed Nd:YAG dental laser was found to be both safe and effective for surface caries removal.

Adult↗

PubMed2002

Cementoblastoma: an innocuous neoplasm? A clinicopathologic study of 44 cases and review of the literature with special emphasis on recurrence.

The clinicopathologic features of 44 cases of cementoblastoma were analyzed and compared with those of 74 cases from the literature with special emphasis on the clinical behavior, treatment, and recurrence rate of these relatively rare benign odontogenic neoplasms. The cases in the current series were accessioned at the Armed Forces Institute of Pathology, Washington, DC. Patient ages at diagnosis ranged from 8 years to 44 years, with a mean age of 20.7 years. The tumors affected 30 males and 14 females. The mandible was the site of occurrence in 31 cases (70.4%), with the mandibular first molar the most common tooth involved. Radiographically, more than 90% of the tumors presented as well-defined radiopaque or mixed-density masses confluent with the tooth root(s) and surrounded by a radiolucent rim. Two lesions were radiolucent. Microscopically, cementoblastomas share similar features with osteoblastomas but are unique because of their physical attachment to the tooth root(s). Follow-up was obtained in 35 of 44 cases, with a mean follow-up interval of 5.5 years. Recurrence was documented in 13 cases (37.1%), in contrast to the literature, where only 2 of 34 cases (5.9%) with adequate follow-up recurred. Jaw expansion and perforation of the cortex were noted in a higher percentage of recurrent than nonrecurrent tumors. Because recurrence and continued growth are possible if lesional tissue remains after initial surgery, appropriate treatment should consist of removal of the lesion along with the affected tooth or teeth, followed by thorough curettage or peripheral ostectomy.

Adolescent↗

PubMed2002

Bloodborne pathogens: current concepts.

In the early 1980s, the AIDS hysteria began to gain momentum. As a direct result of this phenomenon, the delivery of dental care changed dramatically. By 1989, most dentists had begun to accept the concept of universal precautions and compliance with infection control recommendations from the Centers for Disease Control and Prevention and the Organization for Safety & Asepsis Procedures. The emergence of bloodborne pathogens from the 1970s has been a significant milestone in the history of the dental profession. Patients infected with human immunodeficiency virus, hepatitis B virus, and hepatitis C virus are commonly encountered in the modern dental practice, and dental providers need to have a thorough knowledge about bloodborne diseases and the dental management of patients presenting with these diseases.

AIDS-Related Opportunistic Infections↗

PubMedDate not supplied

Comparison of computer-assisted brush biopsy results with follow up scalpel biopsy and histology.

Oral brush biopsy results were compared with scalpel biopsy and histology to determine the positive predictive value of an abnormal brush biopsy finding. Of 243 patients with abnormal brush biopsies, 93 proved positive for dysplasia (79) or carcinoma (14) and 150 were negative for either dysplasia or carcinoma. Therefore, the positive predictive value of an abnormal brush biopsy was 38% (93/243). By using the oral brush biopsy, dentists can inform their patients that abnormal findings have a strong positive predictive value for dysplasia or carcinoma and therefore require follow-up confirmation by scalpel biopsy.

Adolescent↗