The human tuftelin gene: cloning and characterization.

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.

Gerodermia osteodysplastica: report on two patients and surgical correction of facial deformity.

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.

Dentinoenamel junction area in primary teeth affected by Morquio's syndrome.

Separation of dentin from enamel in the dentinoenamel junction area was achieved in primary teeth affected by Morquio's syndrome. Enamel and dentin junctional surfaces were examined by means of scanning electron microscope. These two tissues were found to be separated by a layer of amorphous material. Recurrent treatment of the amorphous layer with NaOCl caused its gradual removal, exposing the rod tips on the enamel side and tubules on the dentin side. It is reasonable to suppose from this finding that the amorphous layer is rich in organic matrix. It is suggested that this amorphorus layer is analogous to the enamel-dentin membrane, that in this syndrome is only partially calcified.

Dentinoenamel junction area of a resorbing permanent incisor studied by means of scanning electron microscopy.

The surfaces of enamel and dentin that had become separated from each other presumably in the region of the dentinoenamel junction were examined. The enamel surface at the junction was scalloped; the scallops were made of enamel rods. The dentinal surface showed a mirror image picture, tubular in nature. Both surfaces were granulated, which may indicate that apatite crystals from the two tissues intermingle there.

A clinical and histometric study of gingivitis associated with the human deciduous dentition.

This study examined the relationship between clinical indices and the histologic parameters associated with the gingiva of the human deciduous dentition. The plaque index, gingival swelling and color, probing depth, bleeding on probing, contact with adjacent teeth and the degree of root resorption of 58 deciduous teeth were recorded. The teeth were extracted with their surrounding gingiva and prepared for histologic examination. The area of epithelium and connective tissue with and without inflammatory cells was measured as well as the epithelial length from the gingival margin including the junctional epithelium. When these measurements were grouped according to the values of the clinical indices, nonmobile teeth were found to have less epithelium than those with mobility and gingiva with a healthy color had a significantly smaller inflammatory cell infiltrate than red gingiva. Bleeding and increased probing depth were not associated with the other clinical signs of inflammation. The amount of plaque did not correlate with the measures of clinical inflammation. The inflammatory cell infiltrate was present irrespective of whether the gingiva was clinically normal or not and the inflammation did not correlate with the amount of plaque.

Periodontitis associated with Papillon-Lefèvre syndrome.

The predominant subgingival microflora, host immune response, and genetic history of a 14-year-old girl with Papillon-Lefèvre Syndrome (PLS) are reported. The patient had high counts of Actinobacillus actinomycetemcomitans and surface translocating bacteria. She had significantly raised levels of antibodies to five of the bacterial species studied with the levels to A. actinomycetemcomitans remaining high after antibiotic therapy. The polymorphonuclear leukocytes (PMN) also released significantly increased amounts of O2 compared to controls. The data presented support a role for A. actinomycetemcomitans and PMN dysfunction in the pathogenesis of PLS.

Relation of pre- and intraoperative factors to prognosis of posterior apical surgery.

The relation of preoperative and intraoperative factors to the prognosis of apical surgery was studied in 136 premolar and molar roots. The evaluated factors were: clinical signs and symptoms, size of the periapical lesion, root canal obturation, tooth restoration, apical retrofilling, and the operating surgeon. A significantly higher success rate was found in roots obturated 2 mm or shorter of the apex, in roots without post restoration, and after retrofilling of roots with apparently well-condensed obturation. The prognosis differed significantly following treatment by various operators but was unrelated to their experience.

Treatment results of apical surgery in premolar and molar teeth.

The purpose of this investigation was to study long-term treatment results following apical surgery in premolars and molars. These results were assessed by reexamination of 136 roots on which apical surgery was performed. The observation period varied from 6 months to 8 yr. According to radiographic and clinical criteria, the treatment results were considered successful in 44.1% of the roots, doubtful in 22.8%, and unsuccessful in 33.1%. Clinical signs and symptoms were associated with 33.1% of the roots, occurring significantly more in roots demonstrating radiographically unsatisfactory healing. The results are discussed with reference to other studies on apical surgery in posterior and anterior teeth. However, methodological differences do not permit the drawing of direct comparisons to those studies.

Interpositional bone grafting technique to widen narrow maxillary ridge.

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.

Dentigerous cysts associated with supernumerary teeth.

Dentigerous cysts associated with supernumerary teeth are rare and estimated to constitute 5-6% of all dentigerous cysts. They resemble the usual dentigerous cysts in terms of sex predilection and age distribution. The vast majority, about 90%, are associated with a maxillary mesiodens. The literature is reviewed and 6 additional cases reported.

Tumors and tumor-like lesions of the oral cavity and related structures in Israeli children.

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.

Squamous odontogenic tumor. Review of the literature and case report.

Squamous odontogenic tumor (SOT) is a rare, benign odontogenic tumor affecting both jaws in all age groups. The tumor is composed of squamous epithelial islands surrounded by a mature connective tissue stroma. This tumor may occasionally be misdiagnosed as ameloblastoma, squamous cell carcinoma, verrucous carcinoma and keratoacanthoma. A conservative surgical approach is the recommended treatment. An additional case is reported and the literature reviewed.

Gaucher's disease affecting the mandible and maxilla. Report of a case.

Gaucher's disease is a rare autosomal, recessive disorder characterized by deficiency of lyzosomal hydrolase glucocerebrosidase, and showing predilection for Ashkenazi Jews. A case of Gaucher's disease affecting both jaws and initially diagnosed by mandibular biopsy is described.

Lichen planus: exploring its malignant potential.

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.

Histologic characteristics of the gingiva associated with the primary and permanent teeth of children.

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.

Central hemangioma of the maxilla.

A case of central maxillary hemangioma is reported in which the only clinical symptom was spontaneous, recurrent, gingival papillary bleeding between the maxillary left premolars. The radiographic findings were inconclusive. It is strongly recommended that in cases where this diagnosis is suspected, surgical intervention be carried out under optimal conditions in an operating theater under hypotensive general anesthesia and with an ample supply of whole blood available.

Mandibular fractures in infants: review of the literature and report of seven cases.

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.