Attacks of 'vomiting and diarrhcea, from acute gastric and intestinal catarrh, are common in teething children. For the reasons which have been stated, infants, whether teething or not, are at all times liable to ready disturbance of indigestion ; indeed, at this age, digestive troubles form a large proportion of their ailments. Therefore, vomiting is especially apt to occur when the stomach is irritable and weak from pyrexia, unless the child's diet be promptly modified to suit the altered state of his digestive organs. In the same way, whether from the irritation of undigested food, or the sensitiveness of the heated body to even trifling variations of the external temperature, purging of a mild character is a very common symp tom. If the teeth are cut in rapid succession, a looseness of the bowels may prevail to a greater or less degree during the whole period of denti tion. If this looseness remains confined within moderate bounds, it may do no apparent harm to the patient ; but it should not on that account be allowed to continue, for at any time a severe attack of inflammatory diar rhoea may supervene, with not improbably fatal consequences. This serious accident is especially liable to occur in hand-fed babies, who, while they are suffering from intestinal irritation, are naturally more than commonly sensitive to the disturbing influence of undigested food. The ordinary diarrhoea of teething consists of green or yellow matter, with small lumps of curd. It is often passed with straining, and its passage is preceded by griping pains.
In cases of chronic diarrhcea, the influence of teething is often distinctly pronounced. The irritation of the gum set up by the advancing tooth tends to maintain an irritable state of the bowels, so that, although the act ual purging may be readily kept under control, an intolerance of milk and the fermentable articles of food continues to prevail, and is very difficult to overcome. Often in such cases, in spite of the most careful dieting, attacks of looseness are frequent ; the child remains weak and low, and seems to make no progress towards recovery. When, however, the tooth appears, and a pause occurs in the process of dentition, immediate improvement is noticed; the motions become healthy, and flesh and strength begin to re turn.
Pulmonary catarrh, with a hard cough, is a common complication of teething ; and the high fever by which these attacks are accompanied may cause great anxiety, as it gives a false appearance of gravity to what is really a trifling ailment. The child coughs a more or less hard cough, which may even have a " croupy " sound ; his flares dilate in inspiration, and the breathing is hurried. His mouth is hot and dry, and dribbling, if it had been previously noticed, ceases when the fever begins. The child is very irritable and restless ; his tongue is furred, and his bowels are confined. The catarrh is usually relieved by appropriate' remedies ; but if care be not taken, and the child be exposed to cold or draught, a really se vere bronchitis or bronchopneumonia may be induced.
Otitis is a not uncommon accident at this period. Dr. Woakes has ex
plained the mechanism by which inflammation of the middle ear is pro duced. Irritation is conveyed from the inflamed gum to the otic ganglion, and is then deflected to the vessel supplying the tympanic membrane. As a consequence, this membrane becomes acutely congested, giving rise to severe pain ; and if the irritation persist, it may lead to inflammation and suppuration within the tympanic cavity. The membrane soon becomes perforated, and a purulent discharge issues from the external auditory meatus (see otitis).
The forms of skin disease which are liable to arise in teething infants are the erythematous rashes and eczematous eruptions. The former are usually transient, and readily subside ; but the latter may spread over the greater part of the body, putting the child to the greatest distress from constant itching, and obstinately resisting Treatment.
Of the nervous disorders which are apt to occur at this period it is very difficult to say how far they are due to the actual process of teething, or to what degree the rapid development of the cerebro-spinal system is answer able for these accidents. In some impressionable infants a very tense, swollen gum may, I believe, like any other variety of irritation in any part of the body, be sufficient to induce an eclamptic attack. In many cases the convulsion is probably to be ascribed to otitis, set up by the state of the gum. Trousseau has suggested that a high degree of fever may be in it self a sufficient cause for the nervous trouble ; but I have never met with a case of convulsions in the child which I could attribute to this cause alone ; for the initial convulsion, which is so common at the beginning of many acute diseases in early life, is probably owing to other causes than mere elevation of temperature. It is easy to understand that an excitable infant, whose whole nervous system is in a state of disquiet from pain, disturbed sleep, and continued dental irritation, may have convulsions induced by a very slight additional stimulits. In such a child a lump of indigestible food, or a scybalous nodule in the bowels, may increase the irritation to an irresistible degree, and it is probable that some such secondary cause often has a share in the production of the eclamptic seizure.
In the second dentition, the order in which the teeth appear is more regular than in the case of the first. The eruption of the permanent teeth begins between the ages of five and a half and seven years with the ap pearance of a permanent molar behind the last of the temporary teeth. Next come the central incisors about the eighth year ; the lateral incisors at about the ninth ; the first and second bicuspids in the place of the temporary molars at the tenth and eleventh ; the canines between the twelfth and thirteenth, and the second molars at about the time of puberty. The last four permanent molars are cut later. The only excep tion to the above sequence that I have noticed is that in rare cases the eruption of the central incisors precedes the appearance of the early molars.