Short answer: Baby molars generally come in between ages 1 and 3. Of the permanent large molars, the first (the 6-year molar) comes in at age 6–7, the second (the 12-year molar) at age 11–13, and the third (the wisdom tooth) generally at age 17–21 or later. The 6-year molar can be mistaken for a baby tooth because it does not replace any baby tooth; yet it is permanent and must be protected carefully.
One of the questions parents often ask when they notice a new tooth in their child's mouth is when molars come in. Molars are found among both baby teeth and permanent teeth, and they come in at different ages. In particular, the first permanent molar, which comes in around age 6, is often mistaken for a baby tooth because it replaces no baby tooth, and it may not receive the care it needs. In this article, we separate baby molars from permanent molars and explain their eruption times, symptoms and ways to protect molars from cavities.
When do molars come in?
Molars come in during two periods: baby molars at roughly ages 1 to 3, and permanent large molars generally at age 6, age 12 and during late adolescence and early adulthood. These times are averages; differences of a few months, and sometimes close to a year, are considered normal in most cases.
Baby molars
In the baby dentition, there are two molars in each half of each jaw. The first baby molars generally come in between 13 and 19 months, and the second baby molars at roughly age 2–3. This way, in most children all 20 baby teeth are in the mouth by around age 3. Baby molars generally give way to the permanent premolars between ages 10 and 12.
Permanent molars
In the permanent dentition, there are three large molars in each half of each jaw:
- First large molar (6-year molar): It generally comes in between ages 6 and 7, right behind the last baby tooth.
- Second large molar (12-year molar): It generally comes in between ages 11 and 13, behind the 6-year molar.
- Third large molar (wisdom tooth): It generally comes in between ages 17 and 21 or later; in some people it never forms or stays impacted.
In addition to these, there are the permanent premolars that replace the baby molars. Although these teeth carry the name "molar," unlike the large molars they come in to replace baby teeth, and there are two in each half of each jaw.
Why is the 6-year molar so important?
The 6-year molar is the first permanent tooth to come in in the mouth; it carries much of the chewing force and plays an important role in forming the bite relationship of the lower and upper jaws. Because this tooth, which is expected to be used for a lifetime, takes its place in the mouth at an early age, it faces the risk of cavities for many years.
The most common problem with the 6-year molar is that it is mistaken for a baby tooth. Because it comes in quietly in the space behind the baby teeth without any baby tooth falling out, families may not realize that this tooth is permanent. In a 6-year molar neglected with the thought that "it will be replaced anyway," a cavity can progress, and this can lead to the need for more extensive procedures such as a root canal. A short rule can be kept in mind: a new tooth that appears behind the baby teeth around age 6 is a permanent molar and will never be replaced.
This tooth has deep grooves (fissures) on its chewing surface. Because the enamel of a newly erupted tooth has not fully matured yet and children find it hard to brush the back teeth, these grooves are open to plaque buildup. We also covered the role of baby teeth in the healthy eruption of permanent teeth in our article on why baby teeth are important.
12-year molars
The 12-year molars are the permanent second large molars and generally come in between ages 11 and 13, behind the 6-year molars. In this period the child is also replacing baby teeth, so the mouth contains both loose and newly erupting teeth.
Because the 12-year molars are in the very back of the mouth, they are hard to brush, and some gum may remain over them for a while during eruption. This period is also the beginning of adolescence; it is an age group in which snacking habits increase and interest in oral care may decrease. For this reason, the 12-year molars need as much attention as the 6-year molars.
The third large molars, that is, the wisdom teeth, are the last link among the molars. You can find detailed information about their eruption times and symptoms in our article on when wisdom teeth come in.
Symptoms when a molar is coming in
The most common symptoms when a molar is coming in are mild swelling and tenderness in the gum, discomfort while chewing and a tendency to touch the area often. The severity of the symptoms varies from child to child; some children never notice the tooth coming in.
- Redness and puffiness in the back gum
- Avoiding that side when chewing hard foods
- In baby molars during infancy, increased drooling, fussiness and a desire to bite things
- Gum partly remaining over the tooth collecting food debris and causing mild tenderness
General symptoms such as high fever, marked facial swelling, long-lasting fussiness or diarrhea should not be attributed only to teething; in such cases, the pediatrician should be consulted. It is also right to consult a dentist or pharmacist before using a pain reliever or gum gel.
In some children, the eruption of permanent teeth may be delayed. We described delays in the front teeth in our article on why permanent front teeth do not come in; if there is a marked delay in the molars, an evaluation with an X-ray may be needed.
Protecting molars from cavities
The basis of protecting molars from cavities is regular and correct brushing, limiting the frequency of sugary foods and, when needed, preventive applications such as fissure sealants. Because of the deep grooves on their chewing surfaces, molars are among the areas where cavities most often start.
- Brushing support: Until their manual dexterity develops, generally until age 7–8, children need adult support in brushing. Make sure the brush reaches all the way to the back teeth.
- Fluoride toothpaste: Using an age-appropriate amount of fluoride toothpaste supports the enamel. Follow your pediatric dentist's recommendation on the amount.
- Fissure sealant: The grooves on the chewing surface of the molars can be closed with a thin, flowable protective material. This procedure is generally applied some time after the tooth has come in, on the teeth the dentist considers suitable. For details, you can look at our article on fissure sealants.
- Eating pattern: Frequent snacking throughout the day and sugary drinks increase the risk of cavities. Choosing water between meals is helpful.
- Regular check-ups: Check-ups every six months or at the intervals the dentist recommends allow early cavities to be noticed early.
You can find all the methods for preventing cavities in children together in our article on how to prevent tooth decay in children.
Molars and jaw development
The eruption order and position of the molars give clues about whether the child will need an orthodontic evaluation in the future. The position of the 6-year molars relative to each other in the lower and upper jaws is one of the basic indicators of the bite relationship. Early loss of baby molars because of cavities can cause the 6-year molar behind to drift forward and leave no room for the premolar coming from beneath. For this reason, protecting baby molars is also important for the proper alignment of the permanent teeth. It is recommended that children have an orthodontic check-up at around age 7; this check-up does not mean treatment will start right away, it allows development to be monitored.
When should you see a dentist?
You need to see a dentist if there is a color change in the molars, pain while chewing, swelling in the gum, or if a tooth does not come in even though the expected age has clearly passed. Also watch for these situations:
- Brown or black lines on the chewing surface of the 6-year molar, or chalky white spots
- Sensitivity that starts with hot, cold or sweet
- Swelling and a bad smell in the gum over a partially erupted tooth
- The tooth on one side having come in while its counterpart on the other side has not come in after months
If you would like to have your child's molars checked, at our clinic in Park Oran Ofis in Oran, Çankaya, children's dental health and jaw development can be evaluated together. At the exam, the condition of the teeth is examined, preventive applications are planned if needed and the time of the next check-up is set.
Frequently asked questions
Is the 6-year molar a baby tooth?
No, the 6-year molar is a permanent molar and will never be replaced. Because it comes in behind the baby teeth without any baby tooth falling out, it is often mistaken for a baby tooth. For this reason, it should be especially protected against cavities.
Does a fever occur when a molar is coming in?
Mild fussiness and gum tenderness can be seen during teething. High fever, diarrhea or long-lasting general symptoms should not be attributed only to teething, and the pediatrician should be consulted.
Is it a problem if the 12-year molars come in late?
The 12-year molars generally come in between ages 11 and 13, and delays of a few months are normal in most cases. If there is a marked delay, or one side comes in and the other side does not for a long time, a dentist's exam and, if needed, an X-ray evaluation are recommended.
Which teeth is a fissure sealant applied to?
A fissure sealant is mostly applied to permanent molars that have deep grooves on the chewing surface. The dentist decides which teeth and when, by evaluating the condition of the tooth and the cavity risk.
When do baby molars fall out?
Baby molars generally fall out between ages 10 and 12, and the permanent premolars come in to replace them. This time can vary from child to child.
