Immediate dentoskeletal and periodontal effects of miniscrew-assisted rapid palatal expansion: Comparison between young vs middle-aged adults.

INTRODUCTION: This study aimed to compare the dentoskeletal and periodontal changes after miniscrew-assisted rapid palatal expansion (MARPE) in patients aged 18-29 and 30-45 years. METHODS: The sample comprised 28 subjects with transverse maxillary discrepancy successfully treated with MARPE. The young adult (YA) group comprised 14 subjects (mean age, 22.8 years; 3 male, 11 female). The middle adult (MA) group comprised 14 subjects (mean age, 36.8 years; 6 male, 8 female). All patients were treated with a 4-miniscrew MARPE expander. The activation protocol was one quarter turn twice a day until the midline diastema opening, followed by one quarter turn a day until overcorrection. Cone-beam computed tomography (CBCT) scans taken before and immediately after the expansion was analyzed using OnDemand3D Dental software. Using CBCT coronal images, transversal dentoskeletal and periodontal variables were measured in the preexpansion and postexpansion. Intergroup comparisons of expansion changes were performed using t and Mann-Whitney tests (P <0.05). RESULTS: Groups were compatible at preexpansion for most CBCT measurements. A success rate of midpalatal suture opening of 100% and 81% was observed for YA and MA groups, respectively. No intergroup differences were found for the maxillary and dental arch widths increases. The buccal tip of anchorage teeth was observed similarly in both groups. The buccal bone thickness of posterior teeth decreased, and the palatal bone thickness increased after expansion with no difference between groups. CONCLUSIONS: After MARPE, the MA group showed similar dentoskeletal and periodontal changes compared to the YA group.

Pain and discomfort perception during miniscrew-anchored maxillary protraction: secondary data analysis of a randomized clinical trial.

OBJECTIVES: To compare the perception of pain and discomfort of patients and guardians during treatment between miniscrew-anchored maxillary protraction (MAMP) therapy using Hybrid (HH) and Conventional Hyrax (CH) expanders. MATERIALS AND METHODS: Group HH was composed of 18 subjects (8 female, 10 male; initial age: 10.80 years) with Class III malocclusion treated with a hybrid expander in the maxilla and two miniscrews in the anterior region of the mandible. Class III elastics were used from maxillary first molar to mandibular miniscrews. Group CH was composed of 14 subjects (6 female, 8 male; initial age: 11.44 years) treated with a similar protocol except for conventional Hyrax expander. Pain and discomfort of patients and guardians were assessed using a visual analog scale immediately after placement (T1), after 24 hours (T2), and 1 month after appliance installation (T3). Mean differences (MD) were obtained. Intergroup and intragroup timepoint comparisons were performed using independent t-tests, analysis of variance for repeated measures and Friedman test (P < 5%). RESULTS: Both groups demonstrated similar levels of pain and discomfort with a significant decrease after 1 month of appliance placement (MD: 4.21; P = .608). Compared to patient perceptions, guardians reported a higher level of pain and discomfort at all timepoints (MD, T1: 13.91, P < .001; T2: 23.15, P < .001; T3: 9.35, P = .008). CONCLUSIONS: MAMP therapy with HH and CH produced similar levels of pain and discomfort after appliance installation until 1 month after treatment. Pain and discomfort may not influence the choice between HH and CH expanders.

Midpalatal suture bone repair after miniscrew-assisted rapid palatal expansion in adults.

BACKGROUND: Midpalatal suture (MPS) repair in growing patients after RPE has been previously reported. However, differences between young and adult patients for timing and pattern of MPS repair after rapid maxillary expansion are expected. The aim of this study was to evaluate the midpalatal suture repair pattern after miniscrew-assisted rapid palatal expansion (MARPE) in adult patients. MATERIALS AND METHODS: The study included 21 patients (six males, 15 females) successfully treated with MARPE with a mean initial age of 29.1 years of age (SD = 8.0; range = 20.1-45.1). MPS repair was evaluated using maxillary axial and coronal sections derived from CBCT exams taken 16 months after the expansion (SD = 5.9). Objective and subjective assessments of MPS repair were performed. Objective assessments were performed measuring MPS bone density at anterior, median and posterior region of hard palate. Pre-expansion and post-retention bone density changes were evaluated using paired t tests (p < 0.05). Midpalatal suture bone repair was scored 0 to 3 considering, respectively, the complete absence of bone repair in the MPS, the repair of less than 50% of the MPS, the repair of more than 50% of the MPS and the complete repair of the MPS. Intra- and interexaminer reliability evaluation were assessed using Kappa coefficient. RESULTS: The objective evaluation showed a significant higher bone density at the pre-expansion stage in all palatal regions. The reliability of the subjective method was adequate with intra- and interexaminer agreements varying from 0.807 to 0.904. Scores 1, 2 and 3 were found in 19.05%, 38.09% and 42.86% of the sample, respectively. The most common region demonstrating absence of bone repair was the middle third. The anterior third of the midpalatal suture was repaired in all patients. CONCLUSIONS: A decreased bone density was observed after the retention period when compared to pre-expansion stage. Most adult patients demonstrated incomplete repair of the midpalatal suture 16 months after MARPE. However, adequate bone repair covering more than half of the hard palate extension was observed in 80.95% of the patients.

Orthopedic outcomes of hybrid and conventional Hyrax expanders.

OBJECTIVES: To compare the effects of a hybrid miniscrew-supported expander versus a conventional Hyrax (CH) expander in growing patients. MATERIALS AND METHODS: Forty patients were randomized into two groups: a hybrid Hyrax (HH) expander group using a Hyrax expander with two miniscrews and a CH expander group. The final sample had 18 subjects (8 female, 10 male; initial age of 10.8 years) in the HH group and 14 subjects (6 female, 8 male; initial age of 11.4 years) in the CH group. Cone-beam computed tomography examinations and digital dental models were obtained before expansion and 11 months postexpansion. The primary outcomes included the orthopedic transverse effects of expansion. Intergroup comparison was performed using analysis of covariance (P < .05). RESULTS: Significantly greater increases in the nasal cavity width, maxillary width, and buccal alveolar crest width were found for the HH group. No intergroup differences were observed for dental arch width or shape changes. CONCLUSIONS: The HH group showed greater increases in the nasal cavity width, maxillary width, and buccal alveolar crest width. No differences were observed for intermolar, interpremolar, or intercanine widths; arch length; or arch perimeter. Arch size and shape showed similar changes in both groups.

Miniscrew-anchored maxillary protraction in growing Class III patients.

The aim of this article is to report a case series of a miniscrew-anchored maxillary protraction therapy (MAMP). Two male patients presenting with Class III malocclusion were included in this report. The treatment consisted of a hybrid expander and two miniscrews at the anterior region of the mandible anchoring Class III elastics for maxillary protraction. Effective maxillary length, ANB angle and Wits appraisal increased after treatment. Slight dental effects were observed. MAMP therapy produced substantial skeletal effects and might be a good treatment option for Class III growing patients.