Journal of Dentistry, 6, No. 2, 1978, pp. 187-188. Printedin Great Britain

JOURNAL OF DENTISTRY

Abstracts from this issue

BRADEN M. ted.1 Dental materials: 1976 literature review. Part II, J. Dent. 6 (1978) 95-l 19.

This paper, which is presented in two parts, reviews the work in dental materials pub- lished in 1976. Included in Part I were sections on amalgam, casting alloys, denture base polymers, composite filling materials, tissue conditioners and soft lining materials and fissure sealants. A review of the liter- ature relating to impression materials, dental ceramics, model and die materials, cements, dental implants and dental bio- mechanics is presented in Part I I.

LAVELLE C. L. B. A metrical study of dental arch form, J. Dent. 6 (1978) 120-124.

Accurate metrical descriptions of the dental arches from different ethnic groups were obtained by recording twodimensional co- ordinates of datum points defined by tooth centres, contact points and buccal and lingual crown convexities. Multivariate stati- stical analyses of these coordinate data showed discrimination between the various dental arches that was not evident visually. Such discrimination implies a predominant role of genetic rather than environmental factors in controlling dental arch form.

MACGREGOR A. Ft., MILLER T. P. G. and FARAH J. W. Stress analysis of partial dentures, J. Dent. 6 (1978) 125-132.

Threedimensional photoelastic stress analy- sis bar been used to examine the stresses on disjunct partial dentures. Three types of denture were studied: tooth-borne, mucosa- borne and tooth- and mucosa-borne. The method of calculating the stresses is outlined and the significance of the findings is discussed.

LILLEY J. D., RUSSELL C., WALKER R. 0. and WATERHOUSE J. A. H. Use and misuse of equipment for dental local analgesia, J. Dem. 6 (1978) 133-146.

Changes in available equipment for dental local analgesia and increased official aware-

ness of the hazards of transmissible disease prompted a survey of the practices in this regard currently followed by the dental profession. A 10 per cent sample of regi- stered dentists was sent a questionnaire drawn up with a view to comparison with earlier studies.

The results indicated a growing aware- ness of the possible microbiological hazards and progressively better understanding of the ways in which to minimize them.

Nevertheless, a disturbing number of practitioners continues to employ inefficient methods. The need for authoritative guidance on the necessity and techniques of rendering discarded needles unusable and for the dis- posal of partly used cartridges is discussed in respect of social and legal responsibilities.

WATT D. M. Tooth positions on complete dentures, J. Dent. 6 (1978) 147-160.

Complete dentures should be constructed to fill the denture space, which may be defined as ‘that space in the edentulous mouth which was formerly occupied by the teeth and their supporting tissues which have since been lost’. The artificial teeth should be placed in the approximate positions occupied by the natural teeth. Various guides to the placement of artificial teeth in these positions are discussed:

1. The form of the lips, the nasolabial and horizontal labial angles and the effect of nose form and tooth inclination on these angles.

2. The relationship of the maxillary incisors to the incisive papilla.

3. General rules for the arrangement of anterior teeth in cases of jaw and lip mal- formation.

4. The location of the remnant of the linguogingival margins in the edentulous mouth and placement of upper teeth in relation to it.

5. Placement of lower teeth in relation to the lower ridge, tongue, cheek and lips.