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Biomedical subjects

M Altini

Publications and source records attributed to M Altini.

At least 37 records · Page 2Linked to original sources
PubMed1992

Ameloblastoma with dentinoid induction: dentinoameloblastoma.

Ameloblastomas do not generally show evidence of induction, however rare cases associated with an odontome have been reported, and are referred to as odontoameloblastoma. In this paper the first known case of an ameloblastoma showing evidence of induction of dentinoid by tumor cells but without concomitant formation of enamel is recorded. The lesion occurred in the angle and ramus of the mandible of a 24-yr-old Asian man and was largely unicystic. In one area however, solid tumor was present which consisted both of infiltrating follicles of typical ameloblastoma tissue and solid sheets of ovoid to spindle cells containing abundant amounts of a homogenous eosinophilic extracellular material, interpreted as dentinoid, and psammamomatous type dystrophic calcifications. Electron microscopic examination of formalin-fixed tissue showed this dentinoid material to consist of interlacing collagen fibrils embedded in a structureless ground substance. At the periphery of the dentinoid globules the collagen fibres were arranged in parallel layers. A final diagnosis of dentinoameloblastoma was made.

Adult↗
PubMed1992

The lateral periodontal cyst: an update.

Lateral periodontal cysts account for 0.8% of all jaw cysts seen in our department. Published reports have indicated that they occur most frequently in the 5th to 7th decades, that there is a male preponderance and that they are located mainly in the mandibular canine-premolar region. In our own series of 20 cases, 10 were found in the anterior maxilla. We have distinguished unicystic and multicystic (including botryoid) varieties. They were lined predominantly or exclusively by thin reduced enamel epithelium-like tissue which contained many clear cells and epithelial thickenings referred to as plaques. Glycogen was present in the epithelium of two-thirds of our cases although not exclusively in the clear cells, many of which showed no positivity. Two of our examples of the botryoid variety were different histologically, being lined predominantly by non-keratinizing stratified squamous epithelium with crowded and pyknotic nuclei and no clear cells. One case contained melanin while another showed epithelial crypt formation and superficial palisaded low columnar cells as seen in the glandular odontogenic cyst. This raised the question of whether the latter may form part of the clinicopathologic spectrum of lateral periodontal cyst. The histogenesis of lateral periodontal cysts is uncertain but we favour origin from reduced enamel epithelium.

Adult↗
PubMed1992

The cementomas--a clinicopathological re-appraisal.

The aim of this study was to assess whether sub-classification of cemental tumors was warranted and to define the clinicopathological features of the definitive entities. Our sample consisted of 127 cases which were divided into the following categories; gigantiform cementoma (84 per cent), cementifying fibroma (12 per cent), benign cementoblastoma (4 per cent). Gigantiform cementoma lesions were either single, multiple or florid and ranged in size from 1 to 10 cm. Most occurred in patients in their 6th and 7th decades who were black (78 per cent) and female (96 per cent). All lesions showed typical solid sheets of acellular cementum and some (22 per cent) were characterised by peripheral proliferative areas which were often indistinguishable from lesions of cementifying fibroma and periapical cemental dysplasia. Infection and sequestration was very common (54 per cent). No cases of periapical cemental dysplasia were found and we suggest that this lesion is a variant of gigantiform cementoma. We believe cementifying fibroma to be part of the histomorphological spectrum of cemento-ossifying fibroma. Cemento-osseous dysplasia is a more accurate and appropriate term than gigantiform cementoma and we recommend the following classification for cemental 'tumors': cemento-ossifying fibroma; cementoblastoma; cemento-osseous dysplasia, single, multiple and florid sub-types.

Adolescent↗
PubMed1991

Peripheral odontogenic fibroma: a clinicopathologic study.

The clinicopathologic features of 30 cases of peripheral odontogenic fibroma are reviewed. The age distribution is wide (11 to 76 years), and there is a slight predilection for males. The majority of the lesions (93%) occurred in blacks on the attached gingiva, and with equal frequency in the maxilla and mandible. Size varied between 1 and 3 cm in diameter. One case recurred after 14 months. Histologically, the lesions are nonencapsulated and poorly delineated. The amount of odontogenic epithelium varies considerably and consists usually of small islands or strands, although larger follicles are sometimes present. In one case the epithelial cells had a clear cytoplasm, whereas in another it was granular and eosinophilic. Origin from the surface oral mucosa can sometimes be seen. The connective tissue component is usually cellular, but collagenous, myxomatous, and mixed forms occur. Calcifications were present in 22 cases and consisted of tissue interpreted as either dentinoid, cementum, bone, or dystrophic calcific material.

Adolescent↗
PubMed1991

Papilliferous keratoameloblastoma.

A case of papilliferous keratoameloblastoma is reported which is only the second ever documented. The patient was a 76-yr-old black woman with a large expansile multilocular radiolucency of the body, angle and ramus of the mandible. Histologically the lesion consisted of sheets of cystic follicles filled with necrotic debris and sometimes parakeratin. The vast majority of the follicles were lined by a papilliferous epithelium consisting of large rounded cells with centrally placed nuclei. True papillary projections with cores of connective tissue were also present. The remainder of the follicles were lined by a thin parakeratinising stratified squamous epithelium. Histological features characteristic of ameloblastoma were absent. Final classification of these lesions will have to await the reporting of further cases.

Aged↗
PubMed1991

Amalgam tattoo as a means for person identification.

Person identification from the teeth depends on establishing a number of points of correspondence between ante- and postmortem dental data, but a single characteristic, if unique enough, may be sufficient. The use of amalgam tattoos in establishing identity has not been reported in the literature. Two cases in which amalgam tattoos were used in conjunction with other dental data to establish identity are reported. Ante- and postmortem radiographs showed the presence of amalgam within the adjacent alveolar bone and periapical tissues, respectively. Attempts were made to duplicate the angulation of the original antemortem radiographs so that a direct comparison could be made of the amalgam fragments. The antemortem radiographs date from 1984 and 1985 in the two respective cases. In both instances the pattern of amalgam remained fairly similar, differences being ascribed to angulation which could not be reproduced exactly. From these results it seems that amalgam tattoo may be a reliable method of identification, even though a number of years may have elapsed since the ante- and postmortem radiographs were taken. The pattern of amalgam dispersal may be sufficiently unique so that identity can be established using this single characteristic.

Dental Amalgam↗
PubMed1991

Pre-malignant lesions of the oral mucosa in a South African sample--a clinicopathological study.

The clinicopathological features of 130 cases of leukoplakia and 8 patients with erythroplakia of the oral mucosa are reviewed. Cases were selected on the basis of definitions agreed to at an international seminar. The patients with leukoplakia were predominantly men, (1.5:1), most were White (86.2%) and the peak age frequency was the 7th decade. The sites most frequently affected were the buccal mucosa (28.8%), floor of mouth (18.3%), alveolar ridge and gingivae (17.3%) and tongue (12.0%). Clinically, they were classified as homogeneous leukoplakia (70.6%), erythroleukoplakia (11.2%), verrucous leukoplakia (10.6%) and nodular leukoplakia (7.6%). There were no differences in age or site distribution between the sexes but the women tended to have more nodular and verrucous lesions. Most of the patients were smokers (71.5%). There was a highly significant sex difference (p less than 0.01) in the use of tobacco with 42.3 per cent of the women and 19.2 per cent of the men never having used tobacco. The tobacco users were significantly younger (p less than 0.05). Of the 143 lesions biopsied, 60.8 per cent showed no dysplasia, 28.0 per cent mild or moderate dysplasia, 4.2 per cent severe dysplasia/carcinoma-in-situ and 7.0 per cent verrucous or squamous carcinoma. Homogeneous leukoplakias have a very low frequency of dysplasia while in the case of the other clinical types the frequencies of dysplasia and malignancy are substantially higher reaching 33.3 per cent invasive malignancy in the case of the nodular lesions. The sites at greatest risk are the floor of the mouth, soft palate, alveolar ridge/gingivae, tongue and buccal mucosa in order of decreasing frequency.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Fibromatoses of the oral and paraoral soft tissues and jaws. Review of the literature and report of 12 new cases.

The clinicopathologic features of 3 new cases and 28 cases obtained from the literature of fibromatosis of the oral and paraoral soft tissues and 9 new cases and 51 cases obtained from the literature of desmoplastic fibroma of the jaws are reported and reviewed. The results of the literature review show that all of the soft tissue lesions occurred before the age of 30 years (mean age, 8.3 +/- 7.0 years). There was a slight male predilection (male to female, 1.2:1). Most cases occurred in the paramandibular soft tissues and mandibular mucosa. Surface resorption of the underlying bone was a common feature. The recurrence rate was 22% and all of these were controlled with further therapy. The desmoplastic fibromas occurred in a slightly older age group (mean age, 14.7 +/- 12.1 years) although 88% of the patients were still younger than 30 years. There was no sex predilection. The vast majority occurred in the area of the mandibular body-angle-ramus. Radiographically, half were unilocular and half were multilocular. Some had poorly defined radiographic margins. The recurrence rate was 25%. The treatment of choice is surgical resection with wide margins, especially for cellular lesions and for those that erode bone with invasion of adjacent soft tissues. Microscopically, both peripheral and central lesions consist of variable proportions of collagen and fibroblasts with a uniform histologic appearance. Hyalinization of collagen is variable but is more frequent in the intraosseous lesions. The cells show no features of anaplasia, and although occasional mitoses may be found, they are always normal in appearance.

Adolescent↗
PubMed1989

Rhabdomyosarcoma of the oral and paraoral region.

Oral rhabdomyosarcoma (RMS) was studied by analysis of eight such cases which presented over a 25-year period. Rhabdomyosarcoma was the fourth most common oral sarcoma (7.5%) from this period after osteosarcoma (32%), fibrosarcoma (19%), and chondrosarcoma (9%). In patients younger than 20 years, RMS was the second most common sarcoma (six cases) after osteosarcoma (ten cases). Combined analysis with 113 further cases documented in the literature showed the majority of cases (71.2%) were embryonal. The alveolar subtype was considered a distant second in frequency (12.3%) even though the pleomorphic subtype was apparently more common (16.4%). However, the pleomorphic cases were diagnosed before histologic criteria were established to discern this entity from other pleomorphic sarcomas and this data is probably unreliable. Site predilections were found for the soft palate, maxillary sinus and alveolus, posterior mandibular region, cheek and lip and possibly tongue. The gingiva and floor of mouth were uncommon sites. There was a predilection for occurrence in the first two decades with a decline in the third decade. Documentation of recent cases treated with a multidisciplinary approach indicated that lesions in the oral soft tissues have a good prognosis; 17 of 21 such cases showed no evidence of disease after a mean follow-up period of 7.2 years (SD = 4.4). In contrast, four of five cases in the posterior mandible resulted in death after a mean period of 1.1 years (SD = 0.3).

Adolescent↗
PubMed1989

Use of the avidin-biotin-peroxidase immunostaining technique on previously stained histologic sections.

A recent report has demonstrated that the avidin-biotin-peroxidase (ABP) technique can successfully be used on previously stained histologic sections without the loss of sensitivity. In this study the tissues had been microwave fixed and only H & E stained sections were used. This procedure was tested on formalin-fixed tissues previously stained with H & E, PAS and van Gieson. Stained sections were prepared from selected blocks used as controls. One week after staining the sections were decolorized and together with the unstained control sections were restained with the ABP technique using IgA, IgD, IgE, IgM, kappa and lambda light chains, S100, EMA, LCA, amylase and PCK antisera. Demonstration of the tissue antigens was best with the previously stained H & E slides with little or no loss in sensitivity. Variable results were obtained with the PAS and van Gieson slides, the loss of sensitivity varying from none to complete.

Avidin↗
PubMed1989

The causation of oral precancer and cancer.

Most cases of oral cancer result from the action of exogenic carcinogenic agents, some of which act synergistically in producing their effects. The evidence implicating tobacco and alcohol abuse is overwhelming and cannot be refuted. Other clearly identifiable aetiological agents include betel nut chewing and excessive exposure to sunlight. While there is increasing evidence of a viral causation, this is not yet clearly established. Similarly, the role of Candida albicans remains uncertain. Lichen planus and discoid lupus erythematosus may constitute important predisposing conditions, but the documentation remains inadequate and inconclusive, as does that implicating electrogalvanism. Tertiary syphilis is no longer considered a significant factor in oral cancer. Sideropenic dysphagia and haemoglobin and serum iron deficiencies may be of importance in the development of oral carcinoma, particularly in elderly women with no history of tobacco and alcohol abuse. The roles of poor oral hygiene and sharp edges of teeth and dentures have probably been overemphasized in the past.

Humans↗
PubMed1988

The unicystic ameloblastoma: a clinicopathological study of 57 cases.

A clinicopathological study of 57 unicystic ameloblastomas has been undertaken, which represents 15% of all cases of ameloblastoma accessioned in our department over a 30-yr period. Of the cases where gender was recorded: 30 were male and 23 female. The majority of patients were black (51 cases) and most occurred in the mandible (52). This distribution conforms to that of solid and multicystic ameloblastomas. The mean age at diagnosis was 23.8 years (S.D. 14.9) which is significantly younger than for the conventional counterpart (p less than 0.1%). The lesions were classified histologically into 3 groups: Group 1 (42%) cyst lined by a variable often non-descript epithelium; Group 2 (9%) cyst showing intraluminal plexiform proliferation of epithelium; Group 3 (49%) cyst with invasion of epithelium into the cyst wall in either follicular or plexiform patterns. While Group 1 and 2 lesions may be treated by enucleation, Group 3 lesions should be treated aggressively as for conventional ameloblastomas. The objectives of correct histological diagnosis, subclassification and appropriate therapy are best achieved by enucleation biopsy. There is little evidence to support origin from pre-existing odontogenic cysts.

Adolescent↗
PubMed1987

The paradental cyst: a clinicopathologic study of 50 cases.

The paradental cyst is an odontogenic cyst of inflammatory origin, which occurs on either the buccal, distal, or (rarely) mesial aspects of partially erupted mandibular third molars. In most cases there is an associated history of recurrent pericoronitis. The clinicopathologic features of 50 cases are reviewed. The frequency of the paradental cyst is 3% to 5% of all odontogenic cysts, although we believe its true incidence to be higher. All cases occur in the mandible, and there is a marked preponderance in males. White persons are affected more frequently than blacks. The size of the cysts varies from 1 to 2 cm; they are attached to the cementoenamel junction (CEJ) and the coronal third of the roots. Histologically, they cannot be distinguished from other inflammatory odontogenic cysts. While origin from junctional epithelium or cell rests of Malassez cannot be entirely excluded, we favor an origin from reduced enamel epithelium and suggest that cyst formation occurs as a result of unilateral expansion of the dental follicle secondary to inflammatory destruction of bone and periodontium.

Adolescent↗
PubMed1987

Experimental extra-follicular histogenesis of follicular cysts.

An animal model has been developed in which implantation cysts have been produced very close to developing teeth within the jaws of Vervet monkeys. Various deciduous teeth were extracted from both the maxilla and the mandible of 6 young Vervet monkeys. After 4 weeks, full thickness mucoperiosteal flaps were raised in these areas, up to 6 recipient sites were prepared in each monkey by drilling holes in the alveolar bone and small pieces of autogenous palatal mucosa were placed in these graft recipient sites. One monkey was killed after 5, 8, 22 and 25 weeks respectively and 2 after 52 weeks. Of the 33 implants placed, cyst formation occurred from 11 (33%). The distribution of the cysts was irregular in that 4 cysts were produced in each of 2 animals while no cysts were found in another 2 animals. The cysts produced were filled with keratin and lined partly by a thick keratinising epithelium and partly by a thin non-keratinising epithelium only a few cell layers thick. In one of the animals killed after 52 weeks, the follicle of an erupting premolar tooth had collided with one of the cysts resulting in the cyst lining becoming incorporated into the follicle, partly replacing the follicular reduced enamel epithelium and forming now an integral part of the follicle. This observation supports the hypothesis that the follicular odontogenic keratocyst has an extra-follicular origin arising after the eruption of a tooth into a pre-existing cyst cavity.

Animals↗