Author Correction: Yolk sac macrophage progenitors traffic to the embryo during defined stages of development.

This article contains errors in Figs. 5 and 6, for which we apologize. In Fig. 5f, the image 'E12.5 tail' was inadvertently replaced with a duplicate of the image 'E12.5 trunk' from the same panel. In Figure 6d, the image 'E9.5/OH-TAM E8.5, embryo' was inadvertently replaced with a duplicate of the image 'E10.5/ OH-TAM E8.5, embryo' from Fig. 6b. The corrected versions of these figures appear in the Author Correction associated with this Article.

Localised aggressive periodontitis in a 3-year-old-boy.

BACKGROUND: Localised aggressive periodontitis (LAgP), characterised by rapid attachment and bone loss, which may occur in children and adolescents, without clinical evidence of systemic disease. CASE REPORT: Three-year-old boy was referred with excessive mobility of 83 and exfoliation of 73. Clinical examination revealed acceptable oral hygiene. Blood tests were performed to evaluate PMNs activity and the parents were advised to apply 0.2% chlorhexidine twice a day. One month later 83 was still excessively mobile. Blood tests were normal. TREATMENT: A full mouth scaling and curettage were performed under general anaesthesia. Since 83 had been spontaneously exfoliated one day earlier, a biopsy was taken from its socket. The biopsy examination revealed granulation tissue with actinomyces colonies. A course of amoxicillin 250 mg three times a day for 7 days was prescribed. Cultures from periodontal pockets of the child's family members were found negative to Aggregatibacter actinomycetem comitans (Aa). FOLLOW-UP: Examination 3 months later, no tooth mobility was observed and the cultures from the periodontal pockets were negative to Aa. Thereafter, the child was periodically reviewed every 3 months for 26 months with no signs of periodontal disease. CONCLUSION: Amoxicillin combined with curettage around the involved teeth may be effective in LAgP treatment.

Yolk sac macrophage progenitors traffic to the embryo during defined stages of development.

Tissue macrophages in many adult organs originate from yolk sac (YS) progenitors, which invade the developing embryo and persist by means of local self-renewal. However, the route and characteristics of YS macrophage trafficking during embryogenesis are incompletely understood. Here we show the early migration dynamics of YS-derived macrophage progenitors in vivo using fate mapping and intravital microscopy. From embryonic day 8.5 (E8.5) CX3CR1+ pre-macrophages are present in the mouse YS where they rapidly proliferate and gain access to the bloodstream to migrate towards the embryo. Trafficking of pre-macrophages and their progenitors from the YS to tissues peaks around E10.5, dramatically decreases towards E12.5 and is no longer evident from E14.5 onwards. Thus, YS progenitors use the vascular system during a restricted time window of embryogenesis to invade the growing fetus. These findings close an important gap in our understanding of the development of the innate immune system.

A stratified myeloid system, the challenge of understanding macrophage diversity.

The present issue of 'Seminars in Immunology' addresses the topic of macrophage biology, 100 years after the death of Elie Metchnikoff (May 1845-July 1916). As foreseen by Metchnikoff, the roles of macrophages in the maintenance of homeostasis and immunity against pathogens have become a broad and active area of investigation. We now start to realize that the myeloid system includes a multiplicity of cell types with diverse developmental origins and functions. Therefore, the textbook picture of a plastic and multifunctional macrophage does not meet the requirements of our current knowledge anymore. Further development toward a quantitative and molecular understanding of myeloid cell biology in vivo and their roles in tissue homeostasis and remodeling will benefit from taking this complexity into account. A tentative model to help in this pursuit and account for myeloid cell and macrophage diversity is discussed below.

[A review of the oro-dento-facial characteristics of hereditary sensory and autonomic neuropathy type III (familial dysautonomia)].

The oro-dento-facial features and dysfunction of children with hereditary sensory and autonomic neuropathy type Ill, known as familial dysautonomia or Riley-Day syndrome, was first described in the scientific literature in 1949. They include dental trauma; dental and soft tissue self-mutilation; normal dental age; normal sequence and timing of eruption and exfoliation of teeth; smaller tooth size; different and disproportional tooth components; normal alveolar bone height; small jaws, mild crowding, and malocclusions. These persons have craniofacial morphology that is different from accepted norms but they resemble norms of their ethnic origin. The subjects can have gray, pale, shiny faces with an asymmetric suffering expression; frontal bossing, with eventual hypertelorism and narrow lips; a low caries rate; drooling, and hypersalivation. They can have changes in salivary composition and content, which influences plaque and calculus and increases the risk of gingival and periodontal diseases. They also have difficulty in controlling oral muscles; a progressive decrease in number of tongue fungiform papillae, accompanied by lack of taste buds; and specific dysgeusia, but a normal sense of smell.

Enamel, dentine and pulp in talon primary maxillary central incisors: a histomorphometric study.

AIM: To examine whether a talon incisor has an abnormal shape due to excess of dental hard tissues or pulp. METHODS: Two bilateral primary maxillary central incisors with talon cusp and a supernumerary mesiodens were removed from a 6-year-old boy. Histologically, 7 undecalcified cross sections (70 microm) were harvested from each talon tooth and from two regular primary central incisors of another child. Microradiographs of the sections were prepared and examined for enamel width, dentin width, pulp tissue area, and crown size (mesio-distal, labio-palatal) using Image Analysis. RESULTS: No association to other developmental disorders was observed. The mean width of the enamel and dentin was similar in the talon and the regular incisors (difference 7.5% and 2.4%, respectively). The pulp area was greater in the talon teeth (37.4%). The latter had an effect on the increase in the mesio-distal and labio-palatal dimensions of the talon teeth (17.6% and 23.9%, respectively). CONCLUSIONS: The fact that the talon cusp has normal enamel and dentin layers with a substantial enlarged pulp tissue suggests that similar developmental anomalies occur during tooth morphodifferentiation as in taurodontism and dens evagintus of premolars.

Treatment policies among Israeli specialists in paediatric dentistry.

AIM: This was to evaluate some suggested diagnostic procedures, treatment policies and professional attitudes of specialists in paediatric dentistry, in light of the periodically published guidelines by The American Academy of Pediatric Dentistry, The European Academy of Paediatric Dentistry and The British Society of Paediatric Dentistry. METHODS: Using a structured questionnaire, 67% of the Israeli specialists in paediatric dentistry, who agreed to participate in this study, were personally interviewed. RESULTS: Only 7.5% of the participants reported that they carry out pulp capping of primary teeth in cases of pulp exposure. Over 50% reported restoring teeth after pulpotomy with preformed crowns. Most indicated sealing pit and fissures after considering depth and morphology of the fissures and correlation with the patient's risk to caries. Cleaning teeth after eruption of the first tooth was suggested by 75.5% of the participants. A striking majority (96%) claimed that they restored permanent anterior teeth with composite resins and most used these materials for occlusal restoration in both primary and permanent posterior teeth. Most specialists advocated the use of amalgam in proximal posterior restorations. The presence of a parent in the operatory/surgery was preferred by 85% of the dentists. CONCLUSIONS: Israeli specialists in paediatric dentistry mostly comply with the mentioned guidelines. Further studies of this nature should also be encouraged in other countries to emphasize the importance of monitoring compliance with established and evidence based guidelines.

Case report: multiple endocrine neoplasia type 2B misdiagnosed as familial dysautonomia.

BACKGROUND: Familial dysautonomia (FD) is a rare autosomal recessive disorder of the peripheral nervous system, affecting exclusively Jewish children of Ashkenazi extraction. The typical clinical features consist of somatic abnormalities: failure to thrive, characteristic facies, excessive sweating, labile blood pressure, recurrent aspiration pneumonias, lack of tears, and diminished and later absent deep tendon reflexes with generalized reduction of pain sensation. Oro-dental features include a lack of tongue fungiform papillae, impairment of taste, oro-dental self-mutilation, dental crowding, excessive plaque and calculus accumulation, salivary over production and low caries experience. CASE REPORT: A child with multiple endocrine neoplasia type 2B (MEN 2B) received, at the age of 11 months, an incorrect diagnosis of familial dysautonomia (FD). At the age of 6 years, a paediatric dentist experienced with FD noticed a normal number and shape of tongue fungiform papillae, while expecting to find a smooth tongue lacking those structures. The presence of numerous submucosal neuromata initiated a meticulous neurological and endocrine work-up, which established the diagnosis of MEN 2B. This led to an early detection and appropriate treatment of asymptomatic medullary thyroid carcinoma (MTC).

Can salivary composition and high flow rate explain the low caries rate in children with familial dysautonomia?

PURPOSE: Extremely low caries rate and increased major salivary gland flow rare have been previously reported in children with familial dysautonomia (FD). The purpose of this study was to explore the possibility that, in addition to increased salivary flow, children with FD have alterations in their salivary components, which may suggest an explanauon to their low caries rate. METHODS: Whole unstimulated and stimulated saliva samples were collected from 13 children with FD who were found to be caries free, and from 28 age- and ethnic-matched healthy children, 15 caries-free children and 13 caries-affected children. The electrolyte and protein content of the unstimulated saliva and the microbial count and buffering capacity of the stimulated saliva were determined. RESULTS: Children with FD had the highest salivary flow rate and the lowest levels of mutans streptococci and lactobacilli, as well as the lowest concentration of chloride, magnesium, total protein and IgA. Healthy caries-affected children displayed the highest mutans streptococci and lactobacilli levels and lysozyme concentration, concomitantly with the lowest potassium and calcium concentrations. CONCLUSIONS: The results of this investigation suggest that the caries-free state in FD may be associated with high salivary flow rate, while in healthy children, low caries rate may be associated with high salivary calcium concentration.

Calcium hydroxide retention in wide root canals with flaring apices.

Calcium hydroxide (CH) is used to induce apexification in immature, pulpless teeth with wide root canals and flaring apices. Three placement methods of CH were compared in vitro, for their ability to enhance CH retention in the canal. Barium sulfate (BS), added as radiopacifier, was studied for its effects on the radiographic follow up of CH retention, as well as on the ability to detect voids in the CH. Calcium hydroxide filled teeth were kept in phosphate buffered saline-containing tubes in a shaker water bath. Radiographs were taken weekly to follow the retention or loss of the material; they were scanned and stored as digitized images. Quantitative evaluations were done on these images, using a computerized gray scale. Condensed CH was better retained in root canals than either lentulo-placed paste or commercial injected paste. Barium sulfate in the CH paste enabled better detection of voids in the paste filling the canal, however, it obscured the disappearance of CH from the canal, due to a residual radiopacity effect. The results supported (a) condensation of calcium hydroxide as a preferred method that improves its retention in wide root canals, and (b) discontinuing the use of barium sulfate as a radiopacifier in apexification procedures.

Radiographic assessment of the alveolar bone height in children and adolescents with familial dysautonomia.

PURPOSE: Familial dysautonomia (FD) is a progressive neuropathy, characterized by somatic and skeletal abnormalities, and by a variety of oral and diet disturbances. The purpose of the study was to assess the alveolar bone height at the molar areas of children and adolescents with FD. METHODS: The distance from the cemento-enamel junction (CEJ) to the alveolar bone crest (ABC) was measured on routine diagnostic bitewing radiographs of nine males and seven females with FD (mean age = 122 months) and in those of two matching groups (C1 = 119 months; C2 = 122 months). RESULTS: The mean values for the maxilla were significantly larger than those in the mandible. A positive significant correlation was found between the CEJ-ABC measurements of the primary and the permanent teeth, and between the CEJ-ABC measurements and age. The mean values per patient for the CEJ-ABC distances of the FD group were smaller than the control groups, but the difference was not statistically significant. The CEJ-ABC measurements in the primary and the permanent molars were smaller in the FD group, and in the premolars and permanent cuspids they were larger than those in the two control groups. These differences were not statistically significant. No differences were found between the FD and the control groups in the primary cuspids. CONCLUSIONS: The alveolar bone height of children and adolescent with familial dysautonomia does not differ from that of healthy controls.

Assessment of compomer proximal restorations in primary molars: a retrospective study in children.

The aim of the present retrospective study was to observe the clinical and radiographic performances of a compomer (Dyract) in proximal restorations of primary molars as compared to amalgam restorations. The study was performed at the principal investigator's office. Children between three to eleven years old, who had at least two primary molars with a small to moderate approximal caries lesion were included in the study. The assessed material consisted of 107 proximal restorations (63 Dyract and 44 amalgam) placed in primary molars during the years 1994 to 1997 in forty-two children who were available for follow-up examinations. All the evaluated restorations were clinically acceptable, with smooth surface appearance, satisfactory color match, neither secondary caries nor fracture. The margins of two Dyract restorations presented minimal stain. Of the 63 Dyract restorations evaluated radiographically, two presented with bubbles, one with an overhang, and nine had pooling at the tooth-restoration interface. Minimal overhangs were disclosed in six amalgam restorations, and neither bubbles nor defects were seen at the tooth-restoration interface. These differences were statistically significant (p < 0.001). Based on the clinical performance of the material and on the radiographic findings, the authors conclude that Dyract can be a suitable alternative for restoring primary teeth that need to be retained up to two years. More extensive follow-up is needed to assess longer-term performance.

Continuous effect of pit and fissure sealing on S. mutans presence in situ.

PURPOSE: The effect of sealants on S. mutans presence in situ was investigated. METHODS: Four intact, fully erupted first permanent molars in each of 74 children, aged 6-8 years were required for inclusion in the study. Baseline examination included deft and plaque index. S. mutans presence on occlusal surfaces of the molars was evaluated, using a microbial replica method. Immediately after sealing the first permanent molars on one side, S. mutans presence in situ was re-evaluated, as well as three and six months thereafter. Three months after the initiation of the study, S. mutans presence was evaluated on the molars of the unsealed side, which were consequently sealed and re-evaluated immediately, and three months later. RESULTS: Positive correlation was found between deft scores, plaque indices and microbial replica values, at baseline. Sealing caused a significant reduction in S. mutans levels on the treated occlusal surfaces, in vivo (P < 0.001), which lasted, in most cases, up to six months. CONCLUSIONS: The data suggest that sealants enable a prolonged reduction of S. mutans presence in situ, indicating an additional prevention effect, by reducing one source of dissemination.

The effect of composite resin application and radiation techniques on dye penetration in Class II direct composite resin restorations.

This study examined the effect of the application of resin composite and radiation techniques on dye penetration in class II direct composite resin restorations. For the restorative procedure, the light-cone and the incremental layering techniques were used. The null hypothesis of this experiment was, that both techniques have the same influence on dye penetration. Evaluation of dye penetration in the restoration/tooth interface was performed in 20 extracted premolars and molars. On each tooth, two class II cavities were prepared. The cervical margin of the proximal boxes were located in dentin or in enamel. When the gingival margin of the cavity was located in enamel, a significant lower level of dye penetration of the the test group was found (Wilcoxon rank test, P = 0.0102). This study showed that the application of a transparent cone seems to be more effective than the three increments technique in the mechanical separation of the first composite increment. Transmitting the curing light into the proximal box, seems to have no positive effect on dye penetration in class II direct composite resin restorations.

A study of small superficial capillary hemangiomas on the lips in children.

PURPOSE: This study describes 77 small vascular lesions on the lips of 74 children and adolescents. RESULTS: Of the 77 lesions, 70% were on the lower lip and 30% on the upper. The diameter range was 0.5-5.0 mm (mean 1.4 mm). On both lips the lesions were in the vermilion zone, close to the border with the skin. The surface of the lesions was smooth and slightly raised, and varied in color from red (49%) through bluish red (45%) to purple (6%). The borders were well defined in most cases. The histology of the lesions was consistent with capillary hemangioma. Small superficial capillary hemangiomas (SSCH) in this study behaved differently from most hemangiomas and vascular malformations in that they did not increase in size, and were persistent in the age group in which most hemangiomas are reported to involute or disappear. The gender distribution of SSCH also differed from the female predominance in hemangioma. SSCH is a solitary benign lesion on the lips of children and adolescents, which has not been separately classified before. CONCLUSIONS: Based on the differences from hemangioma in gender distribution, size, border definition, and growth characteristics, it is suggested that SSCH be classified as a variant or a subgroup of hemangioma.

A cephalometric evaluation of craniofacial morphology in familial dysautonomia.

OBJECTIVE: The purpose of this study was to delineate the craniofacial and dentoalveolar morphology of patients with familial dysautonomia (FD) in order to contribute to the understanding of the association between progressive sensory and autonomic neuropathy and the characteristic appearance of the dysautonomic face. PATIENTS: The study group comprised 32 patients with FD (15 females and 17 males; mean age 10.8 years, SD 3.5 years, range 5.8-19.8 years). DESIGN: Lateral cephalograms from each patient were traced twice. The means of the two measurements were compared with homologous cephalometric normal values of ethnic-specific and classical norms from the literature. RESULTS: In some parameters, the craniofacial morphology of the FD group was significantly different from the classical norms. There was a pronounced retrognathism in the mandible and a steep mandibular plane angle. The skeletal features of FD patients more closely resembled those of their ethnic group, although they were more retrognathic, and the mandibular growth axis was more horizontal. The incisors of these patients were more retropositioned and retroclined than were those of their healthy counterparts. CONCLUSIONS: The results suggest an insufficiency of the expected dentoalveolar compensatory mechanism that usually helps to bridge skeletal discrepancies. It is postulated that the neuropathy is probably the important factor in the lack of this compensatory mechanism.

Taste and smell in familial dysautonomia.

Familial dysautonomia (FD) is one of the classic diseases characterised by taste and smell abnormalities. However, these typical features are based on data obtained from two separate crude studies published in 1964. In the present study psychophysical-cognitive and reflex-like facial-behavioral responses to taste and smell, in nine patients with FD and 15 healthy controls, were recorded. Five taste stimulants were presented to both study groups, while a selection of common household odors was used for FD patients only. The patients with FD showed a markedly higher incidence of recognition failures for salty, bitter, sweet, and water stimuli than the controls, but rate of recognition of sour stimuli was almost identical in the two groups. Estimates by the subjects on a hedonic scale of 0 to 10 and facial display in FD indicated a relatively normal sensitivity to sour stimuli and to a lesser extent to bitter stimuli. Water, sweet, and salty stimuli evoked non-discriminatory responses. These findings indicate specific dyageusia rather than general ageusia. Smell was found to be normal. In children with taste and smell impairment, a systematic evaluative approach may help in planning palatable diets for adequate and comfortable nutrition.

Electronic apex locator: a useful tool for root canal treatment in the primary dentition.

The purpose of this study was to test the ability of an electronic apex locator, Root ZX to measure the root canal length in primary teeth with partial resorption. Twenty extracted primary molars were embedded in an alginate model imitating in vivo conditions. Root ZX and radiographic measurements were compared in dry and wet environments to the actual tooth length. Root ZX identified the tooth length at the most coronal portion of the resorption. The content of the root canal did not influence the results. No statistical differences were found between electronic, radiographic and actual tooth length measurements, although the radiographic measurements were longer than the electronic ones. It is suggested that Root ZX is a preferable auxiliary device to measure root canal length in the primary dentition.

Abnormal enamel and pulp dimensions in familial dysautonomia.

In familial dysautonomia (FD), a hereditary autonomic and sensory neuropathy, somatic growth is impaired. This study was conducted to explore the possibility that tooth dimensions are altered as a consequence of neural crest dysfunction known to be present in FD. Enamel, dentin, pulp, and tooth size measurements of mandibular primary and permanent molars from FD patients were compared with those of healthy controls. It was found that although tooth size in the FD patients was smaller than normal, the enamel was thicker on the occlusal table, while the pulp chamber was smaller and disproportional to tooth size. Our results suggest distorted tooth dimensions rather than a generalized growth arrest as observed in other hereditary syndromes, such as Down's or Crouzon.

Increased major salivary gland secretion in familial dysautonomia.

Familial dysautonomia (FD), an autosomal recessive peripheral nervous system disorder, affects almost exclusively children of Jewish Ashkenazi origin and causes profound generalized autonomic dysfunction. Excessive drooling is frequent and is traditionally attributed to swallowing difficulties. Although true hypersalivation has been postulated, no quantitative assessment of the salivary secretion rate has yet been reported. The authors determined this rate in 13 children with FD and 28 healthy controls. Resting parotid, submandibular/sublingual and unstimulated whole salivary secretion rates were significantly elevated in children with FD. The known relation of salivary function with age was found in controls only. This apparently major contribution of salivary hyperfunction to excessive drooling in FD may be attributable to salivary gland denervation supersensitivity, as this mechanism is present in the cardiovascular system and the pupil in FD.