Objective: To compare the clinical performance and skeletal stability of connected mini-implants and surgically placed mini-plates as skeletal anchorage systems during maxillary anterior en-masse retraction. Materials and Methods: A prospective split-mouth clinical study was conducted on 10 patients requiring maximum anchorage following extraction of the maxillary first premolars. Connected mini-implants were placed on the right side, while surgical mini-plates were placed on the left side. The inter-radicular distance was measured 4 mm apical to the cementoenamel junction using cone-beam computed tomography (CBCT), and customized connector plates were fabricated accordingly. Mini-implants were inserted at an angulation of 45°–70°, whereas mini-plates were fixed in the infrazygomatic crest. Clinical outcomes including tissue overgrowth, postoperative pain, discomfort, oral hygiene, healing, patient acceptance, implant mobility, and placement time were recorded. Skeletal stability was assessed using CBCT by measuring positional changes relative to the Orbitale before and after anterior en-masse retraction. All measurements were performed twice by a single examiner, demonstrating excellent intraobserver reliability (ICC = 0.971). Results: Both anchorage systems provided effective skeletal anchorage during anterior en-masse retraction. CBCT analysis demonstrated no statistically significant differences in positional stability between connected mini-implants and mini-plates. Surgical mini-plates exhibited superior clinical stability with no mobility during treatment. However, connected mini-implants required significantly shorter placement time and were associated with greater patient acceptance and reduced postoperative pain. Tissue overgrowth occurred more frequently around connected mini-implants, although this did not compromise treatment outcomes. Conclusion: Connected mini-implants demonstrated skeletal anchorage stability comparable to surgically placed mini-plates while offering the advantages of a minimally invasive procedure, shorter operative time, and improved patient acceptance. This customized connected mini-implant system may represent a promising alternative to surgical mini-plates for maximum anchorage during maxillary anterior en-masse retraction. Further multicenter studies with larger sample sizes are warranted to validate these findings
Abstract Aim To compare miniscrew stress and displacement, as indicators of mechanical stability, between mono-cortical and bi-cortical miniscrew anchorage configurations in mini-implant assisted rapid palatal expansion (MARPE). Methods A three-dimensional finite element model of the maxilla, teeth, periodontal ligament, and mid-palatal suture was constructed from CBCT data of a healthy adolescent. Two MARPE configurations were simulated: Model A with four bi-cortical miniscrews (anterior and posterior) and Model B with anterior mono-cortical and posterior bi-cortical miniscrews. All structures were assumed isotropic, homogeneous, and linearly elastic and were discretized with tetrahedral and hexahedral elements after grid-independence testing. Bilateral orthopaedic forces of 800 g were applied to each miniscrew under identical boundary conditions. Von Mises stress and displacement were analysed around the miniscrews and in adjacent cortical bone to assess mechanical stability. Results Model A demonstrated more uniform peri-implant stress distribution across all miniscrews, with lower peak von Mises stresses and minimal displacement concentrated in the cervical regions. Model B showed pronounced stress concentration along the middle and cervical thirds of the anterior mono-cortical miniscrews, accompanied by greater miniscrew displacement, indicating reduced mechanical stability relative to bi-cortical anchorage. Conclusion Within the limitations of this finite element analysis, full bi-cortical miniscrew anchorage in MARPE reduces peri-implant stress and miniscrew displacement compared with partial mono-cortical engagement, suggesting superior mechanical stability and a lower risk of miniscrew instability under orthopaedic loading.
Background and objective: Orthodontically induced root resorption (OIRR) is a common sequela of orthodontic tooth movement, and intrusive force is among the movements most strongly associated with it. Conventional radiography detects resorption only after substantial mineralised tissue has been lost and cannot indicate whether resorption is still active. Dentin sialophosphoprotein (DSPP), the principal non-collagenous protein of dentine, is released into the periodontal space during active dentine breakdown and is therefore a candidate biomarker. This trial evaluated the efficiency of DSPP in gingival crevicular fluid (GCF) for the early detection of root resorption in premolars subjected to orthodontic intrusive forces.Methods: Two-arm, parallel-group, controlled clinical trial was conducted at a single university hospital. Thirty-two patients were assessed for eligibility and 20 adults (12 female, 8 male; mean age 22.7 ± 2.6 years for females and 23.4 ± 1.76 years for males) requiring bilateral maxillary first premolar extraction were enrolled and allocated to a study group (n = 10) or a control group (n = 10). In the study group, a 0.017″ × 0.025″ TMA cantilever intrusion spring delivering 50 g of force was bonded to the maxillary first premolar; control premolars were bracketed but received no intrusive force. GCF was collected from the gingival sulcus at T0 (baseline), T1 (4 weeks), T2 (8 weeks) and T3 (12 weeks) and assayed for DSPP by ELISA. Secondary outcomes were the amount of intrusion measured on superimposed digital scans, plaque and gingival indices, and stereomicroscopic and light-microscopic examination of the extracted premolars for resorption craters.Results: All 20 participants completed the trial with no loss to follow-up. Baseline DSPP was comparable between groups. DSPP in the study group rose to 0.066 ± 0.006 IU/L at 4 weeks and peaked at 0.122 ± 0.049 IU/L at 8 weeks, which was significantly higher than the control group (p < 0.001). By 12 weeks the level had returned towards baseline and no longer differed from control. Within the study group, repeated-measures ANOVA with Greenhouse–Geisser correction showed a significant effect of time (p = 0.003). A mean intrusion of 0.566 mm was achieved over 12 weeks (p = 0.002). Plaque and gingival indices remained below 1 throughout and did not change significantly. Light microscopy showed resorption craters in the middle and apical thirds of study-group roots, lined by cellular cementum, with intact cementum in all control specimens.Conclusions: DSPP in GCF rose measurably during orthodontic intrusion, peaked at 8 weeks and declined by 12 weeks, and the microscopic findings confirmed that active resorption had occurred. GCF DSPP is a promising non-invasive marker of active orthodontic root resorption, but because levels are transient a single sampling point may miss active resorption.
Presurgical nasoalveolar molding (PNAM) is an early intervention employed to reposition the alveolar segments and contour the cleft nasal dome, thereby enhancing surgical outcomes. Recent advances in PNAM include the use of thermoform aligners in newborns with clefts, but with certain limitations. Shape-memory aligners featuring dual-phase structures and stimulus-responsive properties deliver consistent, controlled molding, effectively overcoming the limitations of thermoformed aligners in orthodontic uses. We report the application of shape-memory aligners for alveolar molding in a premature infant with unilateral cleft lip and palate. 11 sequential aligner trays were utilized to align the alveolar segments for primary surgical repair. We designated this approach the “4D-AM” appliance, which molds the alveolar segments in all three dimensions (3D), and is effective for a longer duration (4th D - time), owing to the shape-memory effect.
The present report describes treatment of a 13-year-old female who presented with a chief complaint of an unesthetic facial appearance and irregular front teeth. She was born with a nonsyndromic unilateral left cleft lip and palate (CLP): primary lip repair (cheiloplasty) had been performed at 6 months of age, and a secondary alveolar bone graft was placed in the second quadrant at 13 years of age. Clinically, she had a straight profile; facial thirds and symmetry were well balanced, apart from lip changes attributable to the cleft and prior surgical scarring. On intraoral examination, she had severe bimaxillary crowding, multiple unerupted teeth with Angle’s Class I malocclusion and an average growth pattern. Mixed dentition space analysis confirmed a marked arch-length tooth size deficiency in both arches. Treatment involved bonding full-arch fixed appliances with a 0.22 MBT prescription metal brackets followed by guided eruption, leveling and alignment, space closure, and settling. Space was gained with controlled proclination of the incisors and extraction of retained deciduous teeth. Treatment was completed with a Class I molar relationship, achieving Class I canine, ideal overjet and overbite, crowding resolution, competent lips, and a well-balanced facial profile. Circumferential supracrestal fibrotomy was performed for the maxillary central incisors (11, 21) to minimize rotational relapse. Retention was achieved with removable wrap-around retainers in both arches, supplemented by a bonded mandibular lingual retainer.
