626H
Fig. 11.9 Chronic marginal gingivitis
associated with fixed appliance therapy.11.10.2 Gingival enlargement
The anterior palatal gingiva and mucosa have a propensity for enlargement when
tissues are 'rolled up' between incisors that are being retracted and the fixed anterior
margin of the acrylic plate of a removable appliance (627HFig. 11.10 (a) and (b)).
Generally, however, these changes tend to be transient and resolve when appliances
are removed.
628H
Fig. 11.10 (a) Gingival enlargement on the palatal aspect of retracted maxillary
incisors. (b) Appliance in situ. (Reproduced by kind permission of Mr N. E. Carter,
Consultant in Orthodontics, Newcastle.)
11.10.3 Attachment and bone loss
The mean, annual rate of coronal attachment loss during appliance therapy ranges
from 0.05 to 0.30 mm, which compares favourably with figures for the mean annual
attachment loss in untreated populations. A well-recognized complication of
orthodontic tooth movement is apical root resorption, particularly when excessive
forces are used (629HFig. 11.11). Such changes must also be regarded as loss of
attachment, albeit at an apical rather than a coronal site.