Chewing Pattern Changes Before and After Space Maintainer Placement in Children

• Band-and-Loop Space Maintainer (Device): A unilateral fixed band-and-loop space maintainer will be placed as part of routine clinical care following premature loss of a primary molar. The appliance will be cemented to the abutment tooth with glass ionomer cement, and occlusion will be checked after placement. The space maintainer is not assigned for research purposes; it is clinically indicated before study enrollment.

Primary outcomes

• Change in Masticatory Performance [Baseline and 4 weeks after space maintainer placement]: Change in masticatory performance from before space maintainer placement to 4 weeks after placement, assessed using a two-color chewing gum test. After 20 chewing cycles, color mixing will be scored using the Orophys Subjective Assessment Scale from SA1 to SA5, with higher scores indicating more complete color mixing and better masticatory performance.
• Change in Chewing Pattern [Baseline and 4 weeks after space maintainer placement]: Change in chewing pattern from before space maintainer placement to 4 weeks after placement. The dominant chewing side (right/left) will be observed during seven standardized chewing trials. Children using the same side in at least four of seven trials will be classified as unilateral chewers; those showing side alternation will be classified as bilateral chewers.

Sex: All, ages: 6 Years to 10 Years

Inclusion Criteria:

* Children aged 6-10 years
* Premature loss or extraction of a primary molar in the maxilla or mandible with a clinical indication for a unilateral fixed band-and-loop space maintainer
* The abutment tooth for the space maintainer is vital and either sound or appropriately restored
* Complete dentition on the contralateral side of the arch to allow reliable assessment of chewing function
* No systemic condition affecting chewing function
* Written informed consent provided by a parent or legal guardian; children aged 9 years and older also provide written assent

Exclusion Criteria:

* Severe developmental delay, severe behavioral problems, or neuromuscular disorders that may directly affect chewing function, muscle activity, or treatment cooperation
* Temporomandibular joint disorder
* Current orthodontic treatment
* Anterior or posterior crossbite, open bite, or other skeletal or dental malocclusions that may affect chewing function
* Additional missing teeth in the contralateral arch, including hypodontia
* Craniofacial anomalies, including cleft lip and/or palate syndromes
* Systemic conditions requiring special medical precautions or antibiotic prophylaxis during routine dental treatment