——"World Orthodontic Health Day" Oral Health Care Series Science Popularization (5)
Chi Jingyu, Department of Stomatology, Characteristic Medical Center (formerly 306 Hospital).
Edited by Liu Yan/Cui Yan, Medical Science Popularization Center
As an orthodontist, I have recently met many parents in the clinic to consult: "Doctor, the child's newly replaced teeth are crooked, we checked on the Internet that the arch expansion treatment can solve the problem of unevenness", "Doctor, we have looked at other doctors, saying that the child needs orthodontic arch expansion, so that the teeth are straight", "Doctor, we are going to do arch expansion treatment, and the previous medical institution said that the arch expansion can not be extracted"......
As an orthodontist, I am also a mother of a 13-year-old boy and can understand the anxiety of parents. However, it is important not to choose a treatment method in a hurry, as there are some conditions that require arch expansion and some are not suitable for arch expansion.
First of all, what is bow expansion?
Arch expansion is an orthodontic treatment method used earlier in orthopedic treatment, which uses a large mechanical force to transmit the force to the middle palatal suture through the periodontal tissue of the tooth, causing the separation of the middle palatal suture, and the tension stimulates the adaptive reconstruction of the bone suture tissue to return to the normal structure.
What is the purpose of bow expansion?
Arch expansion is to enlarge the maxillary base bone arch to achieve the purpose of increasing the width of the maxillary dental arch. Treatment of posterior crossbite, crowding of the dentition, and impaired nasal ventilation due to maxillary arch stenosis. Arch expansion is not only to align the teeth, but also to remove obstacles to the growth and development of the teeth, and provide a good environment for the growth of permanent teeth.
When is the timing of bow expansion treatment?
Clinically, it has been shown that it is difficult to enlarge the maxillary mid-palatal suture with mechanical force after the growth and development period, and it is better to take this treatment for puberty, worse at 16-18, and surgery is required after the age of 25. In recent years, the problem that the middle palatal suture cannot be enlarged due to ossification in adults has also been solved by the new MSE technology.
Crooked teeth, first of all, look at the problem of teeth or bones, whether it is a temporary irregularity in the dentition stage or a lack of space for tooth eruption. During the replacement of baby teeth and permanent teeth, when the permanent teeth erupt, the bones are developing in the lateral, vertical, and sagittal directions (side view), and the permanent teeth are larger than the baby teeth (except for teeth 4 and 5), and the jaw bone is not developed, and there will be an "ugly duckling" period.
And there are some abnormal bone development, which requires orthodontic treatment. If it is due to the skeletal contradiction of the transverse problem (i.e. the width of the maxillary arch), then you need to expand the arch, even if your teeth are straight; Conversely, if your maxillary development is normal and the lateral width is sufficient, there is no need for arch expansion, even if your teeth are not aligned, this cannot be treated with arch expansion.
Arch expansion is only one of the early treatments, and for early orthodontists, the orthodontist will focus more on the bone than on the tooth itself. Many parents are concerned about whether the replacement dentition stage (generally the sixth instar tooth begins to erupt at the age of 6 and the second molar, that is, the 7th tooth erupts) is not the focus of orthodontists at this stage. Because bone development is the main contradiction, whether your upper and lower jaws match is like whether the foundation of your house is in the right position, and whether your teeth are neat is the decoration stage after the foundation of the correct house is built.
Orthodontists need to clear the patient of developmental disorders, not over-intervene. The criterion for arch expansion has always been based on whether the jaw bone is growing and developing normally, rather than simply aligning the teeth. The bones are boundary, and the upper and lower jaws need to be matched, and if the arch is not needed to be expanded and the arch is blindly expanded, it will turn the dental malocclusion into a serious bony malocclusion.
Crooked teeth, arch expansion is not a panacea, health is the goal, can not be generalized, disease and treatment methods must correspond, in order to achieve the treatment effect.
(The picture comes from the Internet)