Children's dental health: British expatriate residents in Tokyo, Japan

AIM: To identify in expatriate British parents resident in Tokyo, Japan, their levels of dental health knowledge, patterns of dental health behaviour, and caries status of their children compared to Japanese children. METHODS: 223 parents with children at one school were asked to complete a structured questionnaire. Data were collected on: parental knowledge and behaviours with respect to caries prevention, and sweet consumption of the children. The caries status of the children was established by a clinical examination, using standard criteria. RESULTS: The questionnaire response rate was 66.8%. The mean age of the children was 7.6 years (range 3-11 years). The responses related to 51 British, 21 Japanese, and 20 children who had British and Japanese mixed parents. 33% of British and none of Japanese children had sweet foods frequently. Fluoridated toothpaste was used by 67% of British and 10% of Japanese children. British parents knew about dental caries more than Japanese. 13% of British and 38% of Japanese children were found in the higher caries experience group. CONCLUSION: Parental access to information in the UK and to fluoridated toothpaste in Japan could have helped to prevent dental caries in these expatriate British children.     

Use of alendronate in peri-implant defect regeneration

BACKGROUND: Previous studies have demonstrated an increase in bone mass and density with use of systemic alendronate sodium. This agent acts as an inhibitor of osteoclast activity, and is thought to result in more net osteoblastic activity. The objective of this study was to determine the effects of locally applied alendronate sodium on guided bone regeneration around dental implants. METHODS: Six adult mongrel dogs were divided into 2 groups: one group received alendronate-coated dental implants, and the other group served as control. Two types of dental implants were used in each dog: hydroxyapatite (HA)-coated and titanium machine-polished (TMP), for a total of 4 groups. Dental implants were placed immediately after extraction of the right and left second, third, and fourth mandibular premolars; a resorbable collagen membrane was secured over the implants and defects; and the flaps were closed primarily. Fluorescent labels were administered intravenously on days 0, 6, 12, and 22 to measure bone formation rate. Dogs were sacrificed on day 28. The specimens were sectioned and mounted, and bone formation rate was recorded with a computerized microscopic digitizer. Specimens were stained with Stevenel's blue and van Gieson's picric fuchsin. Bone-to-implant contact was recorded with a computerized microscopic digitizer. RESULTS: The results indicated a significant effect of locally applied alendronate (P < 0.0001) with both types of implants (HA and TMP), as well as the HA coating (P< 0.02) on increased bone formation rate. Additionally, alendronate had a significant effect on bone-to-implant contact, with an increase in the TMP model (P < 0.0001) and a decrease in the HA model (P < 0.0001 ). HA coating also had a significant effect on increasing bone-to-implant contact (P < 0.04). CONCLUSIONS: The results indicate that alendronate increases early bone formation rate around dental implants. Additionally, the local application as described resulted in greater bone-to-implant contact with TMP implants.     

Mandibular deformity associated with Paget's disease. Case report

Paget's disease (osteitis deformans) and osteoporosis represent the commonest systemic bone disorders. Clinically Paget's disease may be mono-, or polyostotic, and is characterized by excessive and disorganized formation and resorption of bone. It may affect any of the facial bones, most notably the skull and the jaws. A case is described in which the only symptomatic manifestation of Paget's disease was mandibular prognathism. The pathogenesis, aetiology, and management are discussed.     

Effects of environmental factors on maxillofacial elastomers: Part IV--Optical properties.

The optical properties of four currently used and two recently introduced maxillofacial prosthetic materials were evaluated after the materials were subjected to the following seven environmental variables: natural weathering; normal aging; two types of adhesives; two types of cleaning agents; and cosmetics. Optical density and color changes were evaluated. The currently used silicones Silastic 4-4210 and Silastic 4-4515, Medical Adhesive type A material, and polyurethane all showed more changes in color and optical density than the newly introduced silicone A-102 material.     

Maxillonasal dysplasia, mandibular retrognathia and cleft palate

The present paper describes the craniofacial form of subjects with maxillonasal dysplasia and reports its occurrence in two siblings who also have cleft palate and mandibular retrognathia. Maxillonasal dysplasia and a cleft deformity may be illustrative of a field effect of a teratogen on developing midface components or even suggestive of a possible inherited etiology.     

Immunohistochemical localization of very late activation integrins in healthy and diseased human gingiva

The β1-integrins (VLA family) are cellular adhesion molecules (CAM) that play a major role in cell-cell and cell-matrix interactions. The expression pattern of CAM was studied in 5 clinically normal volunteers with healthy gingiva and in 18 patients with clinically different stages of periodontitis. In healthy human gingiva α2. α3 and α6 integrin chains were found in a characteristic distribution, showing a broad continuous expression on the junctional and sulcular epithelium sites. The expression of these integrins was demonstrated primarily on the basal cell layers and in some cells of the stratum spinosum. Inflammatory stages of periodontitis revealed further upregulation of α2, α3 and α6 integrins into the junctional and sulcular epithelial cells, which correlated with the stage of the periodontitis and the extent of the cellular infiltration. α4 and α6 were found to be the predominant β1 integrin chains on inflammatory cells. The amount of δ4 and ş6 positive infiltrative cells increased with the number of inflammatory cells. VCAM-1. the corresponding cell-cell ligand of VLA-4 (α4) was present on the majority of subepithelial vessels in all stages of gingivitis and periodontitis. The α5 subunit was expressed on both endothelium and gingival connective tissue cells. Samples from advanced periodontitis cases showed a higher number of a5 positive mononuclear cells. In comparison to normal epidermis, a human gingival epithelial cells express higher levels of integrins. This expression is further upregulated in advanced stages of periodontitis, indicating changes of the β1 integrin organization.     

Infrequent clinicopathological findings in 108 ameloblastomas

One hundred and eight ameloblastomas diagnosed in a rural black Africa population were analysed for clinicopathologic findings other than those classically described. One patient had a polycystic ameloblastoma adjacent to an ameloblastic fibroma. Two other polycystic ameloblastomas showed aneurysmal bone cyst formation and one mandibular tumour was diagnosed as a keratoameloblastoma. Microscopic changes resembling an adenomatoid odontogenic tumour were present in association with two unicystic ameloblastomas and a HPV18-positive verrucous lesion occurred in the lining of a cystic space of a polycystic ameloblastoma. Two ameloblastomas contained eosinophilic granules in all tumor cells and melanocytes were diffusely present in another. One case exhibited a focus of mucous cell metaplasia. Two polycystic ameloblastomas showed diffuse interstitial ossification. One mandibular tumor was diagnosed as a desmoplastic ameloblastoma and another as an odontoameloblastoma. This study demonstrated that although ameloblastomas are regarded as a fairly homogeneous group of neoplasms, detailed investigations prove clinicopathologic diversity in a significant number of lesions.     

Masticatory performance with mandibular implant-retained overdentures

It was investigated in a clinical trial whether the masticatory performance of complete-denture wearers depended on the support for their mandibular dentures by implants or mucosa. The trial involved the provision of a new maxillary denture and either a new conventional mandibular denture (mucosa-borne), a mandibular overdenture retained by two IMZ-implants (implant-mucosa-borne), or a mandibular overdenture on a transmandibular implant (TMI; mainly implant-borne). In comparison with mandibular implant-retained overdentures, subjects with conventional dentures needed 1.5 to 3.6 times more chewing strokes for an equivalent reduction in particle size. No differences in masticatory performance were found between subjects with IMZ-implants and those with TMI. This suggests that the increased stability of the mandibular denture with implants determines the wearer's masticatory performance, rather than the support by implants.     

Sotos syndrome with hypodontia

Sotos syndrome, or cerebral gigantism, is a rare genetic condition characterized by tall stature, gigantism, dolichocephaly, advanced bone age and learning disability. The purpose of this case report is to highlight the dental management of a 10-year-old boy with Sotos syndrome who presented with hypodontia and dental caries.     

Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials

OBJECTIVES: To determine whether parachutes are effective in preventing major trauma related to gravitational challenge. Design Systematic review of randomised controlled trials. DATA SOURCES: Medline, Web of Science, Embase, and the Cochrane Library databases; appropriate internet sites and citation lists. STUDY SELECTION: Studies showing the effects of using a parachute during free fall. MAIN OUTCOME MEASURE: Death or major trauma, defined as an injury severity score > 15. RESULTS: We were unable to identify any randomised controlled trials of parachute intervention. CONCLUSIONS: As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data. We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute.