"If You Miss the 6–7 Age Window, You'll Regret It for Life"... The "First Permanent Tooth" Growing Quietly Behind Baby Teeth [Health Talk]

[Financial News] "At age 6 to 7, it is essential to visit a dentist in advance and check the loss of primary teeth and the eruption direction of permanent teeth."
Kim Su-yeon, a professor of pediatric dentistry at Kyung Hee University Hospital at Gangdong, emphasized, "The 'first permanent tooth' is an important tooth that serves as the standard for all the permanent teeth that will follow. Because it is newly erupted, it is vulnerable to cavities and difficult to care for. Since it is unlikely to recover naturally once damaged, parents need to observe it closely."

The first permanent molar, also known as the six-year molar, is the first permanent tooth to erupt at around age 6. It emerges at the back of the row of molars and is responsible for chewing. It also serves as the standard for determining the alignment and occlusion of the permanent teeth that erupt later. The problem is that it quietly grows behind the primary teeth while they are still in place, making it difficult for parents to notice its eruption. Newly erupted permanent teeth are not yet fully hardened, and the grooves on their chewing surfaces are deep, leaving them vulnerable to cavities for two to three years after eruption.
Parents should carefully monitor the eruption of other permanent teeth as well as the first permanent molars. If a permanent tooth properly dissolves the root of a primary tooth and erupts in the correct direction, there is no need to extract the primary tooth forcibly. It can be left to loosen sufficiently and fall out naturally.
However, sometimes a permanent tooth breaks through crookedly and becomes visible even though the primary tooth has not fallen out. In such cases, the primary tooth should be extracted promptly to prevent the permanent tooth from becoming fixed in the wrong position and disrupting the alignment of the teeth. If the eruption direction is severely misaligned, the primary tooth may need to be removed early to help the permanent tooth move into place. Depending on the condition, active early orthodontic treatment may also be considered.
It is just as important to check whether the number of permanent teeth is normal as it is to ensure that they erupt in the correct positions. If tooth buds do not form properly or too many develop, congenital missing teeth or supernumerary teeth may occur. In cases of missing teeth, the existing primary teeth should be preserved for as long as possible into adulthood. Alternatively, a space maintainer can be used before prosthetic treatment, such as implants, is provided after growth is complete.
Conversely, supernumerary teeth can obstruct the path of normal permanent teeth and cause cysts, so they must be removed. They should be safely extracted at the appropriate time to prevent damage to surrounding teeth and allow the permanent teeth to settle into an even alignment.

Once a permanent tooth has erupted into position, cavities should be actively prevented with a dental sealant, or pit-and-fissure sealant. The deep grooves on the chewing surfaces of molars are filled in advance with dental resin to prevent bacteria from accumulating. This can prevent approximately 70% to 80% of cavities on chewing surfaces.
National Health Insurance coverage currently applies to the first and second permanent molars, which erupt at ages 6 and 12, respectively, significantly reducing the financial burden. However, sealants can wear down or come off over time, making regular checkups every six months to one year important. Combining them with fluoride applications can further improve their preventive effect.
Fluoride strengthens enamel and inhibits the production of acids by bacteria, making it effective in preventing cavities. Professional fluoride therapy, in which a dentist applies a high-concentration fluoride product to the surface of the teeth, is particularly useful during the early stages of eruption, when the enamel is still immature. At home, children aged 6 and older should use a high-fluoride toothpaste comparable to adult toothpaste, containing 1,000 to 1,450 ppm of fluoride, in a pea-sized amount and brush carefully every day. Rather than rinsing several times with water after brushing, children should get into the habit of lightly spitting out the toothpaste foam. This allows the fluoride to remain on the teeth longer and maximizes its preventive effect.
Starting around age 6, when the first permanent molars erupt, children should receive regular checkups every six months so that early cavities can be treated simply and prevented from progressing. Even when a cavity has developed, early detection can make treatment that preserves the nerve possible. However, if a cavity in a first permanent molar is neglected and becomes deep, it can lead to root canal treatment or extraction, potentially damaging the alignment of the permanent teeth and the overall bite.
Professor Kim emphasized, "People need to understand that the dentist is not a place to visit only when a problem arises, but a place to visit regularly to prevent problems. Thorough preventive care and regular checkups during the school years are the most reliable ways to protect dental health for life."
  
[email protected] Jeong Myeong-jin, medical specialist Reporter