Eight out of every ten children. That was the proportion identified by researchers when examining swallowing patterns among preschool children in six kindergartens across Wates District, Kulon Progo Regency. Among 96 children who had lost the crowns of their upper primary anterior teeth, 80.21% exhibited tongue thrusting—a swallowing habit in which the tongue pushes forward between the teeth during swallowing. By comparison, only 21.88% of children with intact anterior primary teeth demonstrated the same swallowing pattern. Tongue thrusting, yakni kebiasaan mendorong lidah ke depan di antara gigi saat menelan. Angka ini kontras tajam dengan kelompok anak yang giginya masih utuh: hanya 21,88 persen yang menunjukkan pola serupa.
The finding is more than just a statistic. It represents the first clinical study to directly investigate the relationship between the loss of upper primary anterior tooth crowns and the development of abnormal swallowing patterns in children aged 4 to 6 years.
When Baby Teeth Are Lost, the Tongue Finds Its Own Way
The study, entitled "The Effect of Upper Primary Anterior Tooth Crown Loss on Tongue Thrusting in Children Aged 4–6 Years," ini diterbitkan dalam Journal of Dentistry, Universitas Padjadjaranwas published in the December 2025 issue of the Journal of Dentistry, Universitas Padjadjaran (Volume 37, Issue 3). The research team consisted of drg. Suci Kurniawati as the principal investigator, drg. Putri Kusuma Wardani Mahendra, and Dr. Indra Bramanti, M.Sc., Sp.KGA(K) from the Department of Pediatric Dentistry, Faculty of Dentistry, Universitas Gadjah Mada (FKG UGM).
Conducted between June and August 2024, the cross-sectional study involved 192 children selected through random sampling. Half of the participants (96 children) had lost the crowns of their upper primary anterior teeth, while the remaining 96 had intact anterior dentition. Tongue thrusting was evaluated using the Weiss and Van Houten method. Each child was asked to swallow approximately 10 mL of water while the examiner gently retracted the lower lip and simultaneously palpated the masseter muscle with the index finger. A child was classified as exhibiting tongue thrusting if the Tongue thrusting protruded between the upper and lower incisors during swallowing
Uji Chi-square test Statistical analysis confirmed a highly significant difference between the two groups (p = 0.001).
Why the Tongue Moves into the Empty Space
From an anatomical perspective, the findings are readily explained. The crowns of the upper primary incisors serve as an anterior seal during swallowing, helping close the front of the oral cavity. When these crowns are lost—whether due to severe dental caries that leave only the roots, trauma, or premature extraction—the tongue naturally adapts by filling the resulting gap. This swallowing pattern resembles that of infants, in whom tongue thrusting is physiologically normal until approximately three years of age. However, persistence of this pattern beyond early childhood becomes a functional disorder.
"Loss of the crowns of the upper primary anterior teeth may impair the function of the anterior teeth as a seal during swallowing. This makes it difficult to close the front of the mouth during swallowing, causing the tongue to be positioned between the upper and lower anterior regions, where it contacts the lips and produces a tongue-thrust swallowing pattern."
The tongue's neuromuscular system—primarily controlled by the hypoglossal nerve and driven by the genioglossus muscle—possesses remarkable adaptive capacity. Unfortunately, this adaptation is not always beneficial. If left uncorrected, persistent Tongue thrusting tongue thrusting may contribute to malocclusion, proclination of the maxillary incisors, anterior open bite , speech disorders, and aesthetic concerns that may ultimately affect a child's confidence.
Interestingly, the study also raised another question: Why did nearly one in five children (19.79%) who had lost their anterior tooth crowns not not develop Tongue thrusting? The researchers suggest several possible explanations. These children may have lost their teeth only shortly before the examination, leaving insufficient time for the swallowing pattern to change. Alternatively, their orofacial development may have been sufficiently advanced to allow the swallowing muscles to adapt without requiring the tongue to move forward.
An Important Message for Parents and Dental Professionals
Until now, debates over whether the premature loss of primary anterior teeth causes Tongue thrusting have relied largely on theoretical discussions and retrospective medical records rather than direct clinical examinations. This study from Kulon Progo helps bridge that evidence gap.
For pediatric dentists, the findings underscore that preserving the crowns of upper primary anterior teeth is not merely a matter of aesthetics or chewing efficiency. It is also an important strategy for preventing orofacial functional disorders that may persist into school age and beyond. Restorative treatment of primary anterior teeth—including stainless steel crowns or composite restorations—should therefore be given greater consideration as preventive measures against future malocclusion.
For parents, the study serves as an important reminder that baby teeth are far from "temporary" or disposable. Children whose teeth have decayed to the point where only the roots remain—or whose teeth have been extracted prematurely—should be monitored carefully, including an assessment of how they swallow.
The researchers also acknowledge several limitations. Comprehensive evaluation of orofacial development was not performed, tongue size was not measured, and parental reports regarding the timing of tooth loss were not always complete. These unanswered questions warrant further investigation through more comprehensive future studies.
Meanwhile, in kindergarten classrooms throughout Kulon Progo, hundreds of children continue to swallow every day, their tongues moving according to patterns that may have been established long before anyone noticed.
Authors: Nanda Ayu; drg. Achmad Zam Zam Aghasy, M.Kes.
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