Teething and tooth change: a calendar from the date of birth

Almost never on its own. The spread in eruption timing is enormous and it is inherited: parents whose teeth came in late tend to have children who are the same. A first tooth at 10–12 months is a normal variant. It is worth seeing a paediatric dentist if there is not a single tooth by 15–18 months — then they look for rarer causes, from missing tooth buds to general conditions. Separately, watch the order rather than the clock: teeth come in pairs and symmetrically, and a break in that symmetry is more informative than being late.

Because eruption follows corrected age — counted from the due date, not the actual birthday. A child born at 30 weeks is two and a half months “younger” than a full-term peer, and their teeth will come in roughly that much later. That is normal. Calendars that do not ask send parents of premature babies into worry by default, and they end up learning about the correction from a doctor. For full-term children the field can be left alone.

That is the first permanent large molar, the sixth from the center. It grows not in place of a baby tooth but behind the whole row, in a spot where there was no tooth before — which is why its arrival goes unnoticed and is not accompanied by anything falling out. It is the source of the most common mistake: taken for a baby tooth and left untreated because “it will fall out anyway”. It stays for life and is statistically the first permanent tooth to be lost. The tool shows a separate note about it once the child turns five and a half.

Usually not — this is a very common picture with the lower front teeth, common enough to have a nickname, “shark teeth”. The permanent tooth erupts behind because its bud sits slightly deeper; the baby tooth normally loosens and falls out within a few weeks and the permanent one shifts forward under the tongue’s pressure. Book an appointment if the baby tooth has not started to loosen after a month or six weeks, if the two rows make chewing difficult, or if it has happened with several teeth at once.

A slight rise in temperature, heavy drooling, irritability and a need to chew everything — yes. High fever, diarrhoea, vomiting and rashes — no, although they are traditionally blamed on teeth. The coincidence has a simple explanation: peak teething falls in the months when maternal antibodies fade and children start getting ill more often. The practical conclusion is one: if a child is clearly unwell, look for the cause rather than waiting for a tooth.

Yes, for several reasons at once. A baby tooth holds the space for the permanent one: remove it early and the neighbors drift in, leaving the permanent tooth without room — one of the common roads to orthodontic treatment later. Inflammation at the root of a baby tooth also sits right next to the developing permanent tooth and can damage it. And the child is simply in pain. This is also why it matters not to confuse baby teeth with the permanent six-year molar, which arrives around age six and never falls out.