Effect of visual impairment upon oral health care: a review.

The incidence of visual impairment is increasing globally and in the United Kingdom due to local and systemic disease, medical advances, and the increasing age of population groups. Despite there being a large number of people resident in the UK with a visual impairment, there is little information available regarding the dental health care and needs of such individuals. As reported in other groups of patients with special needs, many individuals with a visual impairment may only seek oral health care when a problem arises, such as pain. Visual impairment may have a negative effect upon oral hygiene with many blind and partially sighted individuals having worse oral hygiene than sighted peers. This review article was undertaken to examine the literature relating to visual impairment, oral health and dental care. This article will discuss the dental aspects of visual impairment, its implications for obtaining dental care, associated oral conditions and medical complications.

On the structure-property relationship of sound and hypomineralized enamel.

Developmental defects in dental enamel pose significant clinical challenges which have highlighted our limited understanding of the structure and properties of this tissue. In this study, we first investigated the contact-size dependence of the physical properties of sound and hypomineralized enamel, and then examined the microstructure to establish a structural basis for their differing properties. Depth-sensing indentation tests were carried out over a wide range of peak loads in a direction perpendicular to the enamel prisms. Hypomineralized enamel demonstrated stronger penetration dependence for measured hardness and elastic modulus than sound enamel. The microstructure of sound and hypomineralized enamel was observed using field emission scanning electron microscopy and transmission electron microscopy with support of a focused ion beam milling system. Images of sound enamel showed barely distinguishable sheath regions with minimal organic presence. In contrast, hypomineralized enamel showed thicker sheath structures surrounding the prisms and higher levels of organic content within both the prisms and the sheath regions. It is argued that the higher organic content within prism structure was responsible for an initial lower hardness and elastic modulus of hypomineralized enamel under low-load indentation. As the indentation depth increased, the thicker organic-rich sheath regions played a more important role in reducing the mechanical properties of the hypomineralized enamel. On the basis of Spears finite element model [Spears IR. A three-dimensional finite element model of prismatic enamel: a re-appraisal of the data on the Young's modulus of enamel. J Dental Res 1997; 76(10):1690-97], elastic moduli of sound and hypomineralized enamel were predicted, which matched experimental results.

Behaviour of primary incisor caries: a micromechanical study.

OBJECTIVES: To date, there has been no attempt to assess the mechanical properties of the entirety of a smooth-surface carious lesion in primary teeth, despite the fact that these lesions are not only common, but clinically challenging. Therefore, the aim of this study was to describe the hardness and modulus of elasticity across smooth surface lesions of primary incisors. STUDY DESIGN: An in vitro study of the micromechanical properties of primary incisors. MATERIALS AND METHODS: Carious primary incisor teeth were set in resin, sectioned and polished. A series of indentations using the ultra-micro-indentation system were conducted in fully hydrated carious and sound dentine from the minimally affected pulpal region towards the tooth surface. A single set of indentations were duplicated for sound dentine. RESULTS: Although the mechanical properties of the carious dentine varied between the test teeth, the median hardness of the surface, middle and inner (pulpal) region of the carious dentine was 0.01, 0.10 and 0.28 GPa, respectively. The modulus of elasticity of the surface, middle and inner (pulpal) carious dentine was 0.12, 2.16 and 5.98 GPa, respectively. The mechanical properties of the sound dentine varied less, and were consistent between the pulpal and surface regions. Examination of the individual series of indentations indicated that, although the majority of the test teeth showed a decrease in the mechanical properties from the 'unaffected dentine' to the surface of the lesion, in the last 300-500 microm, both the hardness and modulus of elasticity showed a dramatic increase. CONCLUSIONS: This study has confirmed that the carious process has a deleterious effect on the mechanical properties of dentine in primary incisors. This, in turn, increases the likelihood of restorative failure. However, the slight increase in mechanical properties seen at the surface of the carious lesion suggests an increase in mineral content.

Aetiology, diagnosis and treatment of posterior cross-bites in the primary dentition.

INTRODUCTION: Children who present with a posterior cross-bite in the primary dentition may be predisposed to long-term detrimental consequences if the condition is left untreated. Controversy exists in the literature as to the most appropriate time to treat this condition. OBJECTIVES: The aim of this review is to evaluate the need for correcting posterior cross-bites in the primary dentition based on the current understanding of the aetiology, likelihood of self-correction, and consequences of various forms of this malocclusion persisting into the mixed and permanent dentitions. A review of the reported treatment options for management of this condition is also presented. METHODS: Literature pertaining to the epidemiology and management of posterior cross-bites in the primary dentition are reviewed. CONCLUSION: Posterior cross-bites in the primary dentition are relatively common and their causes are numerous. Because a significant proportion of posterior cross-bites self-correct beyond the primary dentition, routine correction in the primary dentition phase cannot be advocated. A unilateral posterior cross-bite as a result of a functional displacement of the mandible is one of the few malocclusions which should be considered for correction in the primary dentition. Further research is needed in the management of this condition.

The treatment of localised hypoplastic and hypomineralised defects in first permanent molars.

Hypoplastic and hypomineralised first permanent molar teeth are a frequent finding in children. The treatment of these teeth can be challenging because of the young age of the patient at presentation and the varying anatomy of the affected surfaces. This article reviews the treatment of these teeth including the use of glass ionomer cements, direct and indirect restorations of composite resin, indirect precious and non-precious alloys, stainless steel crowns, and the timely extraction of severely affected teeth.

Opalescent dentine in two affected siblings.

This report describes the dental findings and management of siblings in a family in which three generations had been affected by osteogenesis imperfecta Type IV with opalescent dentine. Hereditary opalescent dentine, or opalescent teeth, is a pathologic dental condition characterised by a disturbance of dentine formation that occurs concurrently with osteogenesis imperfecta. Osteogenesis imperfecta is a genetically heterogenous group of systemic disorders of the connective tissue. The two siblings affected with opalescent dentine were treated under general anaesthesia, and included stainless steel crowns, extractions, and strip crowns on primary teeth. These reports highlight that appropriate treatment of the dentition of young patients with opalescent dentine should be carried out early in the primary dentition, and that this initial treatment can have long-term benefits in the mixed and permanent dentitions.

Development and testing of the Resistiveness to Care Scale.

A conceptual model and objective scale for measuring resistiveness to care in individuals with advanced dementia of the Alzheimer type (DAT) were empirically generated from the perspective of nursing staff caregivers and through observation of residents with DAT. The resistiveness to care scale (RTC-DAT) was judged to have content validity and reduced to 13 items. Quantifiable scoring procedures and methods for rating videotapes and conducting clinical observations were developed. The RTC-DAT was tested with 68 subjects at three sites. The RTC has a range of 0-156. Initial testing provided reliability estimates of .82-.87 for internal consistency and good to excellent kappas. Criterion-related validity with observed discomfort and construct validity by factor analysis support the RTC-DAT. Measurement issues and recommendations for use in research are discussed.