Quarterly Dental Review 351

With all three procedures, pockets were re duced. the best reduction being achieved with pocket elimination surgery. When attachment levels were considered, subgin- gival curettage appeared to give fractionally better results than the other forms of sur- gery. Pocket elimination surgery was found to reduce the amount of attachment buccally, but only by as little as O-3 mm.

A. Bryan Wade

CAFFESSE R. G., KARRING T. and NASJLETl C. E. Keratinizing potential of sulcular epithelium, J. Periodontol. 45 (1977) 140-146.

An ingenious experiment in which the gin- gival tissue was everted fully, thereby re- moving crevicular epithelium from its normal environment, was undertaken in 3 adult rhesus monkeys.

Evidence is produced to show that the crevicular epithelium in such circumstances becomes keratinized, and it is therefore suggested that the connective tissue, corn- mon to both crevicular epithelium and outer gingival epithelium, stimulates keratin form- ation.

It is suggested that the tooth should be regarded as being in the nature of a wedge inserted through the oral mucosa and that the cells adjacent to the tooth are therefore really deeper cells of an epithelial ridge.

A. Bryan Wade

GUINARD E. A. and CAFFESSE R. L. Localized gingival recessions: I. Aetiology and prevalence, J. West Sot. Periodontol. 25 (1977) 3-9.

The aetiology of gingival recessions, whether localized or generalized, is not fully under- stood. The many factors that have been con- sidered to play a part are reviewed.

In spite of the limited knowledge about recessions, very little research has been done in order to determine its causes. The princi- pal obstacle seems to be the difficulty in reproducing in experimental animals the soft and hard tissue changes associated with gingival recession.

The disappearance of the alveolar process is an immediate finding in an area of gingival

recession. It is thus assumed that the ana- tomical tooth to bone relationship plays a predisposing role in the aetiology of a reces- sion. In this instance, many injurious actions upon the gingiva resulting from improper toothbrushing, direct soft tissue trauma, fraenum pull, bacterial irritants, improper restorative procedures and mechanical trau- matic factors may trigger the production of a recession.

Mandibular incisors and maxillary canines seem to be the teeth most commonly affected by gingival recession. Maxillary posterior segments are supposedly more affected than mandibular teeth. The occur- rence of gingival recession increases with age both in frequency and severity.

M. J. Barsby

GUINARD E. A. and CAFFEBBE R. L. Localized gingival recessions: II. Treatment, J. West Sot. Periodontal. 25 (1977) 10-21.

Gingival recessions present special therapeu- tic problems that often require some form of mucogingival surgery.

Based on present knowledge about tissue interaction and specificity only two types of mucogingival surgical procedures can be applied: pedicle periodontal flaps and free gingival grafts. A review of these procedures advocated for the surgical correction of localized gingival recessions is presented with special reference to their clinical and histological behaviour and evaluation.

Few histological studies have considered sequential healing following the lateral sliding flap procedure. Epithelial and connec- tive tissue reattachment of the replaced tissue to the previously denuded root sur- face has been reported. In some instances a long epithelial attachment with apparently no connective tissue reattachment has been obtained.

The success of a free gingival graft depends upon the connective tissue survival. Thecriti- cal period is the first 48 hours, because there is no vascularization in the graft. The graft vitality is initially maintained by diffu- sion of fluids from the host bed. Revascu- larization starts between the second and third days. There is an anastomosis between vessels present in the recipient bed and those pm-existing in the graft. Vessels from the periodontal ligament may also play a role in revascularization.