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T K Mellor

Publications and source records attributed to T K Mellor.

12 recordsLinked to original sources
PubMed2000

A study to assess inducible nitric oxide synthase expression in oral lichen planus.

Nitric oxide (NO) has been implicated in a variety of diseases but has not been previously studied in oral lichen planus (OLP). Since OLP has a complex immunogenesis with abundant macrophage infiltration, this study determined by immunohistochemistry whether or not the expression of the inducible form of nitric oxide synthase (iNOS) was increased in this condition relative to normal mucosa. Thirty cases of OLP and 10 normal buccal mucosa biopsies were studied utilising primary antibodies to iNOS and CD68, a myelomonocytic marker. iNOS activity was additionally assessed using a [(14-)C]-labelled arginine to citrulline assay. CD68 expression was significantly increased in the cellular infiltrate of all 30 cases of OLP compared with normal mucosa (P<0.009). Although iNOS staining was seen in a minority of cells in nine cases, this was not statistically significant when compared with the absent staining in normal oral mucosa (P=0.26). Furthermore, the minimal iNOS activity found in OLP was similar to that in normal mucosa. We conclude that expression of iNOS by macrophages is downregulated in OLP and discuss the possible reasons for this finding.

Adult↗
PubMed1998

The origin and role of erythema after carbon dioxide laser resurfacing. A clinical and histological study.

BACKGROUND: Transient erythema, which can last up to 3 months after carbon dioxide (CO2) laser skin resurfacing, is a usual side effect with pulsed or rapidly scanned CO2 lasers. OBJECTIVE: We evaluated the cause of erythema in the clinical setting and by histology in order to determine if and how we may decrease it, or even eliminate it. METHODS: Ten patients who underwent resurfacing were recruited to this study. Skin punch biopsies were taken at 0, 7, 21, and 90 days and analyzed by light microscopy. RESULTS: Erythema was noticed from about day 8, when the crusting on the skin surface was exfoliated. It reached its maximum intensity after 14 days, and had disappeared by 60-90 days. Histology showed an early inflammatory response, with an immature neopithelium, and rich vascularization. The normal epidermis had returned by 90 days, and during this period there was reduced optical scattering and absorption in melanin. CONCLUSION: Although the erythema is an unwanted side effect in the patient's eyes, it is to be expected and thus represents the effects of a combination of epidermal immaturity, reduced melanin absorption of light, reduced dermal optical scattering, and increased blood flow secondary to the surgically induced inflammatory response.

Aged↗
PubMed1998

A clinical and histological comparison of flashscanning versus pulsed technology in carbon dioxide laser facial skin resurfacing.

BACKGROUND: Two different carbon dioxide (CO2) laser systems are currently in use for skin resurfacing. The vast majority of lasers use a pulsed beam, like the Coherent 5000C, but Sharplan uses scanning technology. OBJECTIVE: We describe a clinical and histological comparison of these two laser technologies in order to determine if there are differences in the outcome. METHODS: Twenty-two female patients underwent facial skin resurfacing using the Coherent 5000C UltraPulse CPG on one side of the face and the Sharplan Silk Touch on the contralateral side of the face. The clinical appearances were assessed periodically after treatment and punch biopsies were taken preoperatively and after 7, 21, and 90 days. Tissue was stained with Hematoxylin-Eosin, Masson Trichrom, and with the Verhoeff technique. Histological evaluation was performed on randomized samples taken from the same patient. Epidermis/dermis expression, collagen compaction, and elastin fiber quantity were compared to evaluate if any differences existed. RESULTS: The side treated by Coherent healed more rapidly and with excellent cosmesis. Greater erythema was observed on the Sharplan side, but had disappeared at the 90-day evaluation. At this time the quality of the results was similar with no particular difference between the sides treated by the Coherent or the Sharplan lasers. At the histological level, although tissue recovered faster on the Coherent side at the 7-day control, at 90 days the collagen was better compacted and organized on the Sharplan side. Similarly, the quantity of the elastin was significantly more enhanced on the Sharplan side. CONCLUSION: Irradiated laser energy density in relation to time, and the way that it is delivered, should play an important role at the moment of producing collagen shrinkage. The SilkTouch delivers laser energy more aggressively, thereby producing a more intense inflammatory tissue reaction, which results in slower recovery of tissue, compared with the Coherent CPG. More active enhancement of vascularization found in the Sharplan is likely to be the reason for a more effective collagen proliferation and compaction. These changes, together with the increase in elastin in the dermis, may produce longer lasting effects in skin resurfacing.

Adult↗
PubMed1996

A prospective clinical evaluation of the longevity of resorbable sutures in oral mucosa.

A prospective, randomised and controlled clinical investigation was undertaken to evaluate the longevity of resorbable sutures in the oral environment. The sutures investigated were gut, polyglycolic acid and polyglactin 910, were of standard gauge and needle type, and were placed using a standard technique by trained clinicians. The sutures were monitored following apical surgery in 55 patients (110 sutures) and the median survival values were: gut - 4 days, polyglycolic acid - 15 days, polyglactin 910 - 28 days. These differences were highly statistically significant. A postal survey of 30 randomly selected oral and maxillofacial surgeons reveal most prefer to use resorbable sutures, with softgut the most popular choice. Most would like an ideal resorbable suture to last 5 to 14 days and in this respect none of the materials tested appears satisfactory.

Absorption↗
PubMed1995

Foreign bodies of dental origin in the appendix.

Foreign bodies found in the appendix have been reported many times. To date 254 occurrences have been documented. However, only 4 previously reported episodes involve teeth, dental restoration or dental equipment. We present a patient with a 6 month history of intermittent right iliac fossa pain following the ingestion of a gold inlay restoration, which was found at operation to be in the distal appendix. Previous reports suggest that symptoms from foreign bodies in the appendix occur in 73% of cases, and in 93% when the object is sharp. Therefore, appendicectomy is recommended when a foreign body is detected in the appendix, and particularly if it has sharp edges.

Abdominal Pain↗
PubMed1985

Malignant mixed salivary tumor presenting as a mandibular metastasis.

A rare case of a central mandibular metastatic mixed salivary gland tumor is reported which presented following a 45-year history of recurrent benign mixed salivary gland tumor of the parotid gland on the same side. The mandibular tumor included a predominantly benign mixed salivary gland component as well as frankly invasive adenocarcinoma. The clinicopathologic features of the mandibular and residual parotid tumors suggested that the metastatic event may have occurred prior to the development of frank carcinoma in the parotid tumor.

Adenocarcinoma↗