Determination of soft tissue thickness at orthodontic miniscrew placement sites using ultrasonography for customizing screw selection

Introduction A wide variety of factors affect the success of orthodontic miniscrews in clinical situations, including thickness of the soft tissues. Our objectives were to assess area-related and sex-related differences in the soft tissue thicknesses of the buccal attached gingiva of the maxilla and the mandible, and the palatal masticatory mucosa at common orthodontic miniscrew placement sites, and to prescribe a guideline for miniscrew selection for a predictable clinical outcome. Methods The sample consisted of 32 randomly selected adults in the age group of 20 to 25 years. Soft-tissue thickness of the concerned areas was measured intraorally using an A-mode ultrasound transducer probe (Biomedix Optotechnik & Devices, Bangalore, India). Independent t tests, paired t tests, and 1-way analysis of variance with Duncan post hoc tests were used for statistical analysis. Results The palatal masticatory mucosa was 2 to 3 times thicker than the corresponding buccal attached gingiva in both sexes. The thickness of the palatal masticatory mucosa in the midpalatal region was consistently less than 1 mm (range, 0.7-1 mm). The buccal attached gingiva was comparatively thicker in the maxilla than in the mandible, except for the mandibular molar regions. It also was found that the buccal attached gingiva was thicker in women in the maxillary anterior regions, whereas, the thickness was greater in the maxillary posterior regions in the men. Conclusions Evaluating the soft tissue thicknesses before selecting an orthodontic miniscrew can help in providing a definite guide for orthodontists to select an appropriate screw in everyday clinical practice, further enhancing the predictability of miniscrew-assisted orthodontics.