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Primary teeth / Milk teeth


  • As boring as it might be, it is very important for us to understand all about the teeth, their eruption sequence, the names/ number of each different one as it, helps us to understand what can damage each element and how everyone can preserve and protect their teeth.

  • All of us are blessed with two sets of teeth - milk teeth /primary teeth develop when you are in your mum's tummy and it erupts into the mouth usually from the age of six months when you are ready to explore different foods.

  • And then as you grow older, from around 6 years, you get your second/permanent teeth mostly replacing the milk teeth which are taken away by the tooth fairy. But before this, they usually serve the person for usually 5-9 years.

  • The milk teeth are a set of 20 teeth, 10 in each upper and lower jaw each. We always talk about the mouth in quadrants - Upper Right /Upper Left and Lower Right / Lower Left. There are a set of 5 teeth per quadrant, they are your primary Central and Lateral incisors, Canine and then the First and the Second molars.

  • You can see from the chart, the first teeth that erupt is usually the lower central that erupts (sometimes laterals all come together), then the upper central( again sometimes all 4 erupt together), then the lower laterals followed by the upper laterals, then the first molars erupt, then the upper canines, then lower canines, and then the second molars.

Fig 1 -Milk teeth of a 6-year-old

  • The teeth erupt usually in pairs - one on each side of the upper or lower jaw. All the primary teeth should erupt by the time they are 2.5 - 3 yrs old. The complete set of primary teeth is in the mouth from the age of 2 ½ to 3 years of age to 6 to 7 years of age.

  • Every Child is different, some get their baby teeth earlier, some get them later.

  • Girls usually precede boys in tooth eruption.

  • Lower teeth usually erupt before upper teeth.

  • Teeth in both jaws usually erupt in pairs — one on the right and one on the left.

  • Primary teeth are smaller and whiter than the permanent teeth that will follow.

  • As the children grow older the jaw and facial bones begin to grow, creating spaces between the primary teeth. This is a perfectly natural growth process that provides the necessary space for the larger permanent teeth to emerge.


  • The bacterial flora of the mouth, mostly derived from the mother, and then depending on the food habits (like sugary foods) changes - so if the primary teeth have a lot of decays on them, the same bacteria survive on and are passed onto the permanent teeth, causing decay on the permanent teeth, so it is important to make sure the decay-causing bacteria does not thrive in the mouth.

  • They reserve space for their permanent counterparts and help in the alignment and spacing of their permanent teeth. Think of them as important space maintainers for the definitive teeth. So if one of these teeth are lost before time then, the other teeth move into the space - to prevent this we even sometimes use appliances called space maintainers (Link of a blog explaining this very well) - especially if the primary second molar is extracted - so that the erupting permanent molars don’t move forward this method can be used - or else it can lead to crowding of the teeth.

  • They aid in the development of clear speech.

  • If there is tooth decay and infection in baby teeth, this can cause dark spots on the permanent teeth developing beneath it, so especially if a front tooth is infected, it would be advisable to extract the primary teeth and spaces maintained if required.


  • Brushing new teeth can be difficult for the baby and parent as teething is quite a painful and difficult time, with associated fever and stomach upsets. The trick I used with my boys is the distraction method - where I sit them on my lap and either can try watching on the mirror and singing songs / use a tablet or an iPad so they are distracted while I do the brushing. It was some good days and some not so good.

  • For brushing the teeth of babies, I would recommend the use of finger toothbrushes which gives us control while the children may move their head unexpectedly and as it is made out of silicone or softer material that does not hurt the children.

  • I would also advise initially to avoid any toothpaste to get the child used to the brushing and make it a part of the daily routine

  • Children learn best by example, so it would be a good idea to let them see you brushing your own teeth twice a day and then helping them brush as well. This could be an act if you are not really ready to brush your teeth!!

  • You can slowly introduce toothpaste which you only need a smear of toothpaste for toddlers up to 3 years and a pea-size amount for 3 to 6 years. Children's toothpaste usually contains up to 1000 Ppm of fluoride which you should encourage them to spit out and not rinse out.

Fig 2 - Pea size amount of adult toothpaste on the brush with the orange ring and a smear of toothpaste on the brush with the pink ring.

  • For children at higher risk of oral disease, a family fluoride toothpaste (1,350 to 1,500 ppm) is indicated for maximum caries control.

  • If a child is at high risk of caries, we can prescribe them a higher dose of toothpaste with 2800ppm from the age of 10 yrs, to take care to use only a pea-sized amount and to spit out the toothpaste rather than swallow it. For children above 16 years, a 5000 ppm fluoride can be prescribed.

  • It is important to make sure the right amount and the right toothpaste is used and also to avoid children eating or swallowing much of the toothpaste at this age as this could lead to fluorosis and can cause white or brown spots on the developing adult teeth but not to be paranoid about it.

  • Dental fluorosis is a defect in the mineralisation of tooth enamel caused by the intake of excessive amounts of fluoride when primary and permanent teeth are developing. Clinically, the appearance of teeth with fluorosis depends on the severity in its milder form, there are faint white spots or lines or streaks visible only to dentally trained people, to more obvious white spots or lesions and in the severe form, brown staining or pitting of the tooth enamel may be present and an actual breakdown of the enamel may occur.

Fig -3 - Fluorosis -the mild form of white flecks to severe brown stains and pitting of the enamel.

  • Because of the developmental nature of the mechanism for fluorotic effects, children are only at risk of fluorosis of cosmetic importance until the age of around three years when the front teeth develop. During this period, the use of fluoridated products is a risk factor for fluorosis development, with swallowing of toothpaste and mouthwash, but there need to be significant amounts.

  • It has been recommended that in order to balance the benefits of preventing dental caries and the potential harms of fluorosis associated with ingesting fluoride toothpaste, children under three years of age should use only a smear of toothpaste.

  • An average smear is approximately 0.1 ml, which would allow 13 brushing episodes with 1,000 ppm toothpaste per day before breaching the upper tolerable limit of fluoride intake, assuming that 100% of toothpaste used was ingested. (SIGN Guidelines)

  • For children over the age of three years, a pea-sized amount (0.25 ml) per brushing is recommended. This would allow eight brushing episodes with 1,000 ppm toothpaste per day before breaching the upper tolerable limit of fluoride intake. (SIGN Guidelines)

  • Brush the teeth in small circles as this improves efficiency and the least chance of trauma than back-and-forth as this can damage the teeth.

  • As the children grow older, I would recommend a children's toothbrush preferably an electric one.

  • For my children, I use the Oral-B children's electric toothbrush. The 6-year-old brushes with softer bristles initially as he was teething and we will slowly move onto an adult toothbrush head and my older 11-year-old uses an adult electric toothbrush and an adult brush head.

Fig 4 -Picture of my 11-year-old where all his adult teeth have erupted from the central incisors to the first permanent molars in all quadrants

  • I would recommend an adult toothbrush from the age of 12- 13 years when most of their adult teeth have erupted. I use the Oral B IO - 9 (All from 7 to 9 are very similar just better app and AI technology. The IO has combined both the oscillation of the previous Oral B and the vibration of the sonic care (as their patency ran out a year ago). It also lets you customise and track your brushing over days, and it has a phone app that can be used in real-time while you brush your teeth showing that you’ve successfully cleaned the mouth.)

  • Children need to be helped and Supervised with brushing till they are 7 to 8 years of age (or till however old you can do it - as teenagers are quite pathetic at brushing !) and can brush efficiently as this is an age where they get their adult teeth which are the most crucial teeth for adult life, the incisors and the first molars in all the quadrants.

  • If not an electric toothbrush is available to use, then the second-best is to use a manual toothbrush - if possible a round head, with medium bristles, multi-tufted, with either different length bristles/bristles at angles to be used in a ‘Bass technique' of brushing.

  • If children have orthodontics/ braces done - it is very important to maintain good brushing for the benefit to outweigh the risks of getting decay or gum disease from poor oral hygiene.

  • It is important to make the children aware of the importance of healthy teeth and good-looking teeth

  • It is also important to try to make brushing a happy and positive experience.

  • I would also recommend the use of disclosing tablets be used once a week to make sure that the brushing is efficient and it would be a good idea to record this with photographs for comparison purposes. It really helps to have a comparison between siblings and a reward card.

Fig 5: Disclosing tablets used for checking plaque before brushing, as u can see at the upper right central incisor was moving, the brushing in the mouth's front next to the missing teeth is not very good.

  • It’s advised to take the children to the dentist for a check from when they are 1-year-old so that they have a pleasant memory of the dentist just counting their teeth and giving them stickers than them having to have any treatment (which can always be a put off)

  • It helps in identifying issues early and treating them before it becomes painful and or need treatment.

  • The dentist should be able to apply Flouride varnish, at least twice a year in all childreThis is usually is a yellow paste which usually has a banana flavour and very sticky, and so to be left on the teeth for about 30 mins without eating or rinsing your mouth. This helps to strengthen and remineralize the enamel - especially the young newly erupted teeth.

Fig 6: Flouride varnish - applied on children till the age of 18, especially in high-risk cases like - high decay rate, poor oral hygiene, orthodontics, high-sugar diet etc.

The best Oral Hygiene kit to use for children

Fig 7 -Table compiled from the SIGN Scottish guidelines and Oral Health care Toolkit by the England Government site.

Link for Products mentioned.

( As I am told time and again that there are quite a few similar options online I have given the links to the recommended products. As an Amazon affiliate, if you use the link to buy the product, I will get a commission, but the products are unbiased, as I could really mention any product from Amazon, but these are what I use personally and recommend from the research and personal experience.)

  1. Space Maintainers - Blog by Dr Dean Brandon

  2. Kids Electric toothbrush -Oral B ,

  3. Adult electric toothbrush - IO - 9 series , IO- 8 series , IO 7 series (The brushing efficiency is similar I think between these 3, the AI and the app technology seems to improve with the numbers, so like an iPhone, u can get any of these it will all do its job well enough unless you are a techie)


  1. Delivering better oral care - Toolkit by the Gov of UK.

  2. Cochrane Review - Powered toothbrushes are better in the long and short term in reducing plaque - - 2014 .

  3. Systematic Review and Meta-Analysis by D Clary-Perry and L Levin in 2020 that the oscillating toothbrushing (Oral B) works better than a vibrating /sonic care one (like Philips).

  4. Cochrane review - Oscillating toothbrushes better than vibrating toothbrushes in long- and short-term plaque removal - Robinson .et .al - 2004.

  5. Fluoride varnish efficacy in controlling caries in children - Azarpazhooh - 2008

  6. Photographs of Caries in children - Link

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