At 3 years. At 11 years. Intervals between canines 24 mms. 26 mms. ” 1st premolars 26 ” 29 ” ” 2nd premolars 29 ” 32 ” ” 1st molars — 34 ” CHAPTER IX. SYPHILITIC AFFECTIONS OF THE PALATE. This small work will not be complete without some allusion to the destructive effects of syphilis upon the hard and soft structures of the palate, resulting either in loss of substance of the velum, or in the production of apertures which of necessity impair its functions in the same way as do congenital deformities. They occur at different stages of the disease, but mainly in cases which have been neglected, and of which the treatment has been unsatisfactory. In the _secondary_ period the most common manifestation of this disease in the palate is, in its mildest form, simply a moderate injection of the mucous membrane, similar to the roseola seen on the skin. It is situated mainly on the velum and anterior pillars of the fauces, and under efficient treatment soon disappears. Severer manifestations are, however, met with, from the mucous plaque, with its resulting “snail-track” ulcer, to the most serious forms of destructive change. Such severe forms occur usually towards the close of the secondary period, and in persons of vitiated constitution. The process starts in the neighbourhood of the uvula, and involves the velum and pillars of the fauces; the mucous membrane and submucous tissue become hyperæmic and infiltrated with the products of inflammation, and the hyperplasia may be such as even to suggest the presence of epithelioma. Ulceration soon follows, and if the disease be extensive the patient’s condition may become serious from the difficulties experienced in deglutition and respiration. The loss of substance may extend to a variable depth, and subsequent cicatrisation tends more often to produce pharyngeal stenosis than to leave permanent apertures in the velum; as a result, speech becomes indistinct, and the act of swallowing is much interfered with. In many of these cases the primary sore has been intentionally or accidentally overlooked, or no treatment adopted.