What Is Tooth Eruption
Tooth eruption is the process by which a tooth pushes through the gum tissue and becomes visible in the mouth. It is one of the most observable milestones in a child's development, beginning in infancy and continuing through the late teenage years.
Eruption happens in a broadly predictable sequence and timeline. Understanding that sequence helps parents recognize what is normal, identify anything that warrants a dental visit, and ensure each new tooth receives the right care from the moment it appears.
It is important to note that eruption timelines represent averages. A variation of several months in either direction is common and does not, on its own, indicate a problem.
The Two Sets of Teeth: Primary and Permanent
Children develop two complete sets of teeth during their lifetime.
The first set — called primary teeth, baby teeth, or deciduous teeth — consists of 20 teeth. These begin erupting at around six months of age and are typically all present by the age of three. Primary teeth are smaller than permanent teeth and have thinner enamel, but they are not simply placeholders. They allow children to chew and speak properly, guide jaw development, and hold the space that permanent teeth will eventually occupy.
The second set — permanent teeth, also called adult teeth — consists of 32 teeth, including the four wisdom teeth (third molars). The transition from primary to permanent teeth begins at around age six and is not fully complete until the late teens or early twenties, when wisdom teeth either erupt or are assessed for removal.
Primary Teeth Eruption Timeline
Primary teeth usually begin to erupt at around six months of age. The lower front teeth tend to appear first, followed shortly by the upper front teeth. The full set of 20 primary teeth is typically in place by age two and a half to three years.
The sequence below follows the order in which teeth generally erupt. Upper and lower timelines differ slightly.
The sequence below follows the order in which teeth generally erupt. Upper and lower timelines differ slightly.
| Upper (Maxillary) Primary Teeth | Lower (Mandibular) Primary Teeth |
|---|---|
| Central incisors (upper front teeth): 8–12 months | Central incisors: 6–10 months |
| Lateral incisors (either side of the front teeth): 9–13 months | Lateral incisors: 10–16 months |
| First molars: 13–19 months | First molars: 14–18 months |
| Canines (cuspids): 16–22 months | Canines (cuspids): 17–23 months |
| Second molars: 25–33 months | Second molars: 23–31 months |
As a general guide, approximately four teeth erupt for every six months of a child's life during the primary dentition phase.
Teething — the period during which a tooth is actively pushing through the gum — can cause mild discomfort, drooling, and irritability in some infants. A clean, cool teething ring or gentle gum massage can provide relief. A mild temperature rise sometimes accompanies teething, but a high fever is not a symptom of teething and should be assessed by a doctor.
Once the first tooth appears, it can be cleaned with a soft, damp cloth or an infant toothbrush. Use a smear of fluoride toothpaste (the size of a grain of rice) from the first tooth until age three, and a pea-sized amount from age three to six.
Permanent Teeth Eruption Timeline
The permanent teeth begin erupting at around age six, when the first permanent molars appear just behind the last primary molars. These are known as the six-year molars, and they are among the most important teeth in the mouth. They arrive without replacing any primary teeth, which means they are sometimes mistaken for baby teeth — they are not.
The primary teeth are shed and replaced by permanent teeth in roughly the same order they originally erupted, beginning with the lower central incisors.
| Upper (Maxillary) Permanent Teeth | Lower (Mandibular) Permanent Teeth |
|---|---|
| Central incisors: 7–8 years | Central incisors: 6–7 years |
| Lateral incisors: 8–9 years | Lateral incisors: 7–8 years |
| Canines: 11–12 years | Canines: 9–10 years |
| First premolars (bicuspids): 10–11 years | First premolars: 10–12 years |
| Second premolars: 10–12 years | Second premolars: 11–12 years |
| First molars: 6–7 years | First molars: 6–7 years |
| Second molars: 12–13 years | Second molars: 11–13 years |
| Third molars (wisdom teeth): 17–21 years | Third molars (wisdom teeth): 17–21 years |
Most children have 28 permanent teeth in place by their early teens. The wisdom teeth, if they erupt at all, arrive in the late teens to early twenties and are assessed individually for whether they have sufficient space to emerge without affecting adjacent teeth.
Newly erupted permanent teeth, particularly the molars and premolars, have deep pits and grooves on their biting surfaces that are vulnerable to cavities. Dental sealants applied shortly after these teeth emerge can significantly reduce the risk of decay.
What Is the Mixed Dentition Phase
The mixed dentition phase refers to the period between approximately ages six and twelve, during which a child has both primary teeth and permanent teeth present in the mouth at the same time. This phase can look uneven — large adult teeth appearing alongside much smaller baby teeth, gaps where teeth have been lost but their permanent replacements have not yet arrived, and a mouth that seems temporarily crowded or irregular. This is entirely normal.
The mixed dentition phase is clinically important because it is the period during which a Specialist Orthodontist can identify early signs of crowding, spacing problems, or bite issues that may benefit from interceptive treatment. An orthodontic evaluation during this phase does not always mean treatment is needed immediately — but it establishes a clear picture of how the permanent dentition is developing.
During the mixed dentition phase, parents should continue twice-daily brushing and introduce flossing once teeth are touching. Fluoride toothpaste is recommended throughout. A Specialist Pediatric Dentist will monitor the transition at each routine check-up and flag anything that warrants closer attention.
When Should a Child First See a Dentist
A child's first dental visit should take place no later than their first birthday, or within six months of the first tooth appearing — whichever comes first.
This early visit is not primarily about treatment. It is an opportunity to assess how the primary teeth are erupting, introduce the child to a dental environment in a calm and positive way, and give parents practical guidance on feeding, hygiene, and teething.
At Drs. Nicolas & Asp Centers, all children are seen by Specialist Pediatric Dentists who are specifically trained in child development and behavior. Routine check-ups every six months allow the team to track eruption progress, apply fluoride treatment where appropriate, and place dental sealants on newly erupted permanent molars to protect them from decay.
Frequently Asked Questions
The lower central incisors — the two bottom front teeth — are typically the first primary teeth to appear, usually between six and ten months of age. The upper central incisors follow shortly after. Some infants experience their first tooth slightly earlier or later than this range, which is generally normal.
According to the American Dental Association’s guidelines, a primary tooth erupting up to four or five months earlier or later than the average timeline is considered within the normal range. For permanent teeth, a variation of up to 12 to 18 months in either direction is not uncommon. If a tooth is significantly overdue with no sign of movement, a dental X-ray can confirm whether it is developing and identify any reason for the delay.
Primary teeth serve essential functions beyond their temporary role. They allow children to chew food properly, which supports nutrition and jaw development. They guide the eruption path of the permanent teeth that will replace them. Early loss of a primary tooth — particularly a molar — can cause neighboring teeth to drift, reducing the space needed for the incoming permanent tooth. A space maintainer may be recommended to preserve that space if a primary tooth is lost prematurely.
Yes. Our Specialist Pediatric Dentists monitor eruption progress at every routine check-up across all four centers — Jumeirah, Marina Walk, Springs Souk, and Uptown Mirdif. If a tooth is not erupting as expected, or if the eruption pattern suggests an issue that needs investigation or early intervention, we will discuss the findings with you and outline the appropriate next steps. To book a pediatric dental appointment, call us on 04 394 7777 or visit our appointment page.
Children should be seen by a Specialist Pediatric Dentist for all routine dental care and eruption monitoring. If an eruption issue has orthodontic implications — such as crowding, spacing, or a tooth that appears to be erupting in the wrong position — your child's Specialist Pediatric Dentist will coordinate a referral to a Specialist Orthodontist at the appropriate stage of development.
Pediatric dental check-ups and preventive treatments are covered by most major insurance plans, though the extent of coverage varies by policy. At Drs. Nicolas & Asp Centers, we accept most major insurance cards for direct billing and handle all pre-approvals and paperwork on your behalf. Call us at 04 394 7777 and we will be more than happy to check your coverage for you. For more information, visit our Insurance & Payment Options page.
- American Dental Association. "Eruption Charts." MouthHealthy, 2024. mouthhealthy.org
- American Dental Association. "Tooth Eruption: The Permanent Teeth." Journal of the American Dental Association, vol. 137, no. 1, 2006, p. 127. jada.ada.org
- American Academy of Pediatric Dentistry. "Dental Growth and Development." Reference Manual of Pediatric Dentistry, 2023, pp. 614–620. aapd.org
- American Academy of Pediatric Dentistry. "Fluoride Therapy." Reference Manual of Pediatric Dentistry, 2023. aapd.org
- Poureslami, Hamidreza, et al. "Does Timing of Eruption in First Primary Tooth Correlate with that of First Permanent Tooth? A 9-years Cohort Study." Journal of Dental Research, Dental Clinics, Dental Prospects, vol. 9, no. 2, 2015, pp. 79–83. ncbi.nlm.nih.gov
