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Tuftelin has been suggested to play an important role during the development and mineralization of enamel. We isolated the full-length human tuftelin cDNA using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (5' RACE and 3' RACE) methods. Sequence analysis of the tuftelin cDNA revealed an open reading frame of 1170 bp encoding a 390 amino acid protein with a molecular mass of 44.3 kDa and an isoelectric point of 5.7. The human tuftelin protein shares 89 and 88% amino acid sequence identity with the bovine and mouse tuftelin, respectively. It contains a coiled-coil region, recently reported to be involved with tuftelin self-assembly and with the interaction of tuftelin with TIP39 (a novel tuftelin interacting protein). Detailed DNA analysis of the cloned genomic DNA revealed that the human tuftelin gene contains 13 exons and is larger than 26 kb. Two alternatively spliced tuftelin mRNA transcripts have now been identified in the human tooth bud, one lacking exon 2, and the other lacking exon 2 and exon 3. Primer extension analysis, corroborated by RT-PCR and DNA sequencing, revealed multiple transcription initiation sites. The cloned 1.6 kb promoter region contained several GC boxes and several transcription factor binding sites such as those for activator protein 1 and stimulatory protein 1. Our blast search of the human and mouse expressed sequence tag data bases, as well as our RT-PCR and DNA sequencing results, and a previous study using Northern blot analysis revealed that tuftelin cDNA sequences are also expressed in normal and cancerous non-mineralizing soft tissues, suggesting that tuftelin has a universal function. We have now identified and characterized different alternatively spliced mouse tuftelin mRNAs in several non-mineralizing tissues. These results provide an important baseline for future understanding of the biological role of tuftelin.

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A case of bilateral recurrent submandibular sialadenitis is presented in a patient with decreased salivary flow. The condition was caused by trapping of the submandibular papillae between the lingual flange of the denture and the enlarged genial tubercles. Removal of these causes led to resolution of her symptoms. The value of plain radiography, sialography and scintigraphy is discussed.

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This study examined the influence of overretention on the tissues of human primary teeth. The range of overretention was two to thirty-two years. Light microscopy and computerized morphometry were utilized for histologic assessment of twenty-five sites of twenty-one teeth. Dentinoclasts were found on the resorbing root surface of nine teeth; polymorphonuclear leucocytes were found in the pulp of fourteen teeth; and monocytes were present in all pulps. The apical and coronal ends of the junctional epithelium were apical to the cemento-enamel junction in eighteen and fourteen teeth, respectively. Significant correlations were found between the extent of overretention and gingival height, the length of the junctional epithelium and the extent of apical migration of the junctional epithelium. Present and previous findings indicate that odontoclastic activity in the pulp is reduced with overretention; and while at the beginning of overretention there is a lower percentage of pulps with polymorphonuclear leucocytes in the pulp, with an extended period of overretention an increase in this percentage takes place.

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Following a severe traumatic incident to permanent immature teeth, the growth of calcified tissue in the pulp space may occasionally occur. This calcified tissue may be diffuse or in intimate contact with the dentine. It has been suggested that a wide open apex, severe damage to the root sheath, and the absence of infection are only some of the predisposing factors leading to this metaplasia of pulp tissue into bone-like tissue. Five cases are described.

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The present study comprises a total of 966 biopsies of the oral cavity and related structures obtained from children aged < or =15 years and examined at the Division of Oral Pathology of The Hebrew University. These cases represent 7.15% of the total number of biopsies (13508) during a fifteen-year period (1978-1992). Seven hundred and seventy six (776) biopsies (80.3%) represented inflammatory processes, cysts, pulp pathology and congenital malformations. The remaining 190 biopsies (19.7%) comprised neoplastic and tumor-like lesions: 18 (9.5%) were benign odontogenic neoplasms, 77 (40.5%) were benign non-odontogenic neoplasms, 18 (9.5%) were malignant tumors and the remaining 77 cases (40.5%) were tumor-like lesions.

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RT-PCR, Southern blotting and DNA sequencing have established for the first time that tuftelin mRNA is expressed in human ameloblastoma tumor. The expression of amelogenin mRNA in ameloblastoma was also established, confirming earlier reports by Snead et al. These results corroborate, on a molecular level, the enamel organ epithelial origin of ameloblastoma. In view of the present results, it is interesting that previous studies have indicated that although ameloblastoma, a non-mineralized odontogenic tumor, transcribes amelogenin mRNA, amelogenin (and enamelin) proteins are not expressed in this tissue. However, in mineralizing odontogenic tumors, both these classes of proteins are expressed.

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The principles on which the present approach to the treatment of cleidocranial dysplasia are based were stated in part 1 of this article. Comparison was made with two other methods and the advantages of the present method were described in terms of (a) how this method is adapted to the clinical features of the condition, (b) when surgical intervention is appropriate, (c) how the dynamic appliance system may be adapted to the changing environment as more teeth erupt, and (d) the importance of rapidly bringing about the eruption of the anterior teeth. The practical aspects of the treatment are now described step-by-step with illustrations taken from the treatment of several different patients.

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Over several decades, occasional reports of dental treatment provided by an individual practitioner to patients suffering with cleidocranial dysplasia have appeared in the literature. In the past, the main treatment was prosthetic replacement. Orthodontic treatment has only recently been considered as a serious treatment option, with success being described in several aspects of this treatment modality, in published individual case reports. Given the rarity of the condition, guidelines for the treatment of cleidocranial dysplasia are difficult to find in the literature, because few practitioners have treated enough cases to be in a position to make such recommendations. Two different approaches have been proposed in the past and are discussed here. The relative advantages of a third approach are expounded in detail.

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A narrow edentulous alveolar ridge, less than 6 mm in the buccopalatal aspect, can prevent restoration by means of endosseous implants. A widening technique using alveolar ridge splitting and interpositional autogenous bone grafting is described. Accurate imaging of the alveolar bone shape and size was assessed with computerized tomography in a 1:1 scale. Following 6 months of healing, osseointegrated Brånemark implants were placed in the grafted sites.

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The clinical features of 74 patients with Burkitt's lymphoma diagnosed at the Hadassah Medical Center in Jerusalem, Israel, are described. The prompt diagnosis of a child with high grade malignant jaw involvement of non-Hodgkin's Burkitt's lymphoma is reported. The use of the open biopsy with special emphasis on the incisional biopsy is discussed in light of the incidental exfoliation of the two primary molar teeth and one permanent successor in this case.

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Brain heterotopia of the tongue is a rare, congenital malformation, probably not embryologically related to encephaloceles or to the so called "nasal gliomas." The progressive growth frequently noted confers to the lesion a tumor-like appearance and can raise a clinical suspicion of some rare neonatal neoplasia. The non-neoplastic nature of the lesion is well established, and the growth may well be due to the fact that heterotopic brain grows as rapidly as normal brain in the infant. Although local recurrence after incomplete resection has been reported, the clinical behavior of brain heterotopia of the tongue is benign.

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The severity of the gingival inflammatory response to dental plaque increases with age, and it has been suggested that this phenomenon may be related to histological characteristics of the gingiva. The objective of this study was to compare the histological characteristics of the gingival tissues of primary teeth with that of permanent teeth in children. Prior to extraction, children were subjected to a period of thorough oral hygiene. Histological sections prepared from gingival biopsies were examined using the light microscope. One biopsy from each of seven primary and seven permanent teeth of 14 children, whose mean ages were 11.0 +/- 0.9 and 12.9 +/- 0.9 years respectively, was obtained. All sections exhibited clear signs of inflammation. Apical migration of the junctional epithelium onto the root surface was associated only with the primary teeth. Compared with the permanent teeth, the primary teeth were associated with a thicker junctional epithelium (P < 0.05), higher numbers of leukocytes in the connective tissue adjacent to the apical end of the junctional epithelium (P < 0.05), and a higher density of collagen fibers in the suboral epithelial connective tissue (P < 0.01). No significant differences were noted in the width of the free gingiva, thickness of the oral epithelium, or its keratinized layer. In conclusion, this study indicates significant differences in the microanatomy of the gingival tissues between primary and permanent teeth in children.

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Mandibular fractures in infants are rare. During the last 50 years, only 13 cases have been recorded in the literature. In this study seven cases of mandibular fractures in infants treated within a period of 3 years are reported. The male-to-female ratio was 6:1. All fractures were caused by short falls, and in all cases the symphysis region was the injured site. The treatment approach was conservative, without any active intervention. The results were satisfactory; perfect alignment of the fractured bone segments was achieved in all cases.

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Late involvement of the parotid gland in a patient with a limited form of Wegener's granulomatosis is presented. We report the full course of the disease and the difficulties encountered in determining the nature of the parotid enlargement. We discuss the contribution of computerized tomography and ultrasonography to elucidate parenchymal morphologic findings and radioisotope studies to determine the functional capacity of the gland. In cases of Wegener's granulomatosis with salivary symptoms, measurement of salivary gland functional capacity, in addition to the c-ANCA test, may help to monitor disease activity. Despite the rarity of the disease, in cases when granulomatous diseases are considered, it should be recognized that Wegener's granulomatosis may result in salivary gland involvement.

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Hemangiopericytoma is an uncommon vascular tumor of unknown etiology. The tongue is the most common site for this tumor in the oral cavity. Literature review disclosed 20 cases of hemangiopericytoma of the tongue, four of which were in the pediatric population. The treatment of choice is wide surgical excision. This tumor has a high rate of recurrence and often a malignant transformation. The literature is reviewed and an additional case is reported.

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We present four individuals with Gerodermia Osteodysplastica in a Jewish family from Morocco confirming the autosomal recessive inheritance of the disorder. Three previously unreported findings are described: a) enlarged funnel-shaped mandibular lingula; b) extension of the mandibular premolar and molar roots below the inferior dental canal, and of the second molars into the lower border of mandibular cortical bone; and c) hypercementosis of the maxillary incisors and mandibular molars surrounded by a radiolucent halo in several teeth. The facial deformity resulting from maxillary hypoplasia and mandibular prognathism was corrected by orthognathic surgery: Le Fort I maxillary osteotomy and vertical mandibular osteotomy.

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Almost any area of the mouth may be affected by LP, but the most frequent locations are the cheeks, tongue and gingiva. The eight cases in our study illustrate the proliferative epithelial changes to verrucous or squamous cell carcinoma that can appear in oral LP. We also found a predisposition of LP in women. We urge, therefore, that clinicians monitor LP patients closely at three- to six-month intervals and attempt treatment for early resolution.

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A patient with bilateral, insidiously developing enlargement of the parotid glands that started 1 year after a total thyroidectomy and ablative radioiodine therapy (200 mCi I131) for papillary carcinoma is presented. The patient displayed prolonged periods of hypothyroidism accompanied by hypercholesterolinemia, notwithstanding hormone replacement therapy. Three years after surgery, parotid and lacrimal gland functions were reduced and fatty degeneration of the parotid parenchyma was demonstrated histologically. The submandibular and sublingual glands were preserved. It is suggested that the hormonal and metabolic derangements are responsible for the glandular dysfunction, rather than a direct effect of iodine on the glands.

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Five years after a kidney transplant and immunosuppressive therapy a 42-year-old woman had squamous cell carcinoma of the lower lip with an innocent appearance. We present this as the first case of lip squamous cell carcinoma in a kidney transplant recipient to be reported in the dental literature. We review the medical literature.

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