Construction of Customized Palatal Orthodontic Devices on Skeletal Anchorage Using Biomechanical Modeling

Orthodontic implants have been developed for the implementation of skeletal anchorage and are effectively used in the design of individual orthodontic devices. However, despite a significant amount of clinical research, the biomechanical aspects of the use of skeletal anchorage have not been adequately studied. The aim of this work was to numerically investigate the stress–strain state of the developed palatal orthodontic device supported by mini-implants. Four possible options for the placement of mini-implants in the bone were analyzed. The effect of a chewing load of 100 N on the bite plane was investigated. The study was carried out using biomechanical modeling based on the finite element method. The installation of the palatal orthodontic device fixed on mini-implants with an individual bite plane positioned on was simulated. The dependence of equivalent stresses and deformation changes on the number and location of the supporting mini-implants of the palatal orthodontic device was investigated. Two materials (titanium alloy and stainless steel) of the palatal orthodontic device were also investigated. The choice of a successful treatment option was based on the developed biomechanical criteria for assessing the surgical treatment success. Application of the criteria made it possible to estimate the stability and strength of fixation of each of the considered mini-implants installation options. As a result, options for the mini-implants optimal placement were identified (the first and the fourth which provide distributed front and side support of the device), as well as the preferred material (titanium alloy) for the manufacture of the palatal orthodontic device.

Comparison of facemask therapy effects using skeletal and tooth-borne anchorage:

ABSTRACT Objectives To investigate long-term outcomes of dentoskeletal changes induced by facemask therapy using skeletal anchorage in Class III patients and compare them to those of conventional tooth-borne anchorage. Materials and Methods This retrospective study included 20 patients who received facemask (FM) therapy with miniplates as anchorage for maxillary protraction (Miniplate/FM group, 10.6 ± 1.1 years old [mean ± SD]) and 23 patients who were treated with facemask with rapid maxillary expander (RME/FM group, 10.0 ± 1.5 years old [mean ± SD]). Dentoskeletal changes were evaluated using lateral cephalograms at pretreatment (T1), after facemask therapy (T2), and at the post-pubertal stage (T3). Cephalometric changes were compared between groups and clinical success rates at T3 were evaluated. Results SNA and A to N perpendicular to FH increased significantly more in the Miniplate/FM group than in the RME/FM group when comparing short-term effects of facemask therapy (T1–T2). ANB, Wits appraisal, Angle of convexity, mandibular plane angle, and overjet decreased significantly more in the RME/FM group than in the Miniplate/FM group after facemask therapy (T2–T3). A more favorable intermaxillary relationship was observed in the Miniplate/FM group than in the RME/FM group in long-term observations (T1–T3). Clinical success rate at T3 was 95% in the Miniplate/FM group and 85% in the RME/FM group. Conclusions Facemask therapy with skeletal anchorage showed a greater advancement of the maxilla and more favorable stability for correction of Class III malocclusion in the long-term than conventional facemask therapy with tooth-borne anchorage.

Outcomes and Stability of Anterior Open Bite Treatment with Skeletal Anchorage in Non-Growing Patients and Adults Compared to the Results of Orthognathic Surgery Procedures: A Systematic Review

The objective of this review is to evaluate, on the basis of the available literature, if anterior open bite (AOB) can be successfully treated with the intrusion of molar teeth using skeletal anchorage in non-growing patients and adults and if this treatment modality provides comparable results to those obtained by orthognathic surgery procedures. Methods: A systematic review of published data in major databases from 2000 to 2021 was performed. Results: In total, 92 articles were included in title and abstract screening, and only 16 articles (11 concerning AOB correction by molar intrusion with skeletal anchorage, and five considering AOB treatment by orthognathic surgical intervention) qualified for thorough data extraction and analysis. Conclusions: On the basis of this review, it seems to be possible to obtain successful results for AOB treatment in non-growing patients and adults by means of the intrusion of molar teeth with skeletal anchorage. However, due to the different methods of assessing treatment outcomes used by different authors, it is not possible to state conclusively whether the treatment of AOB by means of molar intrusion with skeletal anchorage provides long-term results that are comparable to orthognathic surgery procedures.

Comparison of dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne hybrid nonsurgical rapid maxillary expansions in adults: a retrospective observational study

Background Despite the gradual increase in the use of rapid maxillary expansion (RME), specifically RME with the aid of skeletal anchorage in adults, there have been no reports comparing dentoskeletal and soft tissue changes between nonsurgical tooth-borne and tooth-bone-borne RMEs in adults. This study aimed to analyse differences in dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne RMEs using a similar appliance design and the same expansion protocol in adult patients. Methods Twenty-one patients with tooth-borne expansion (a conventional expansion screw with two premolars and two molar bands for dental anchorage [T-RME]) and the same number of patients with tooth-bone-borne hybrid expansion (a conventional expansion screw with two premolar and two molar bands for dental anchorage and four mini-implants in the palate for skeletal anchorage [H-RME]) were included. Dentoskeletal and soft tissue variables at pretreatment (T1) and after expansion (T2) were measured using posteroanterior and lateral cephalograms and frontal photographs. The sex distribution of the two groups was analysed using the chi-square test, and the change after RME in each group was evaluated using the Wilcoxon signed-rank test. Differences in pretreatment age, expansion duration, post-expansion duration, and dentoskeletal and soft tissue changes after RME between the two groups were determined using the Mann–Whitney U test. Results There were no significant differences in the expansion protocol, pretreatment conditions, and sex distribution between the two groups. Despite similar degrees of dental expansion at the crown level between the two groups, H-RME induced increased skeletal and parallel expansion of the maxilla compared to T-RME. After expansion, H-RME demonstrated increased forward displacement of the maxilla without significant changes in the vertical dimension, while T-RME exhibited increased backward displacement of the mandible, increased vertical dimension, and decreased overbite. Both groups showed significant retroclination and extrusion of the maxillary incisors without significant intergroup differences. There were no significant soft tissue changes between the two groups. Conclusion This study suggests that using skeletal anchorage in RME may induce increased skeletal and parallel expansion of the maxilla without significant effects on the vertical dimension.

Comparison of Dentoskeletal and Soft Tissue Changes Between Tooth-Borne and Tooth-Bone-Borne Hybrid Nonsurgical Rapid Maxillary Expansions in Adults: A Retrospective Observational Study

Background Despite the gradual increase in the use of rapid maxillary expansion (RME), specifically RME with the aid of skeletal anchorage in adults, there have been no reports comparing dentoskeletal and soft tissue changes between nonsurgical tooth-borne and tooth-bone-borne RMEs in adults. This study aimed to analyse differences in dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne RMEs using a similar appliance design and the same expansion protocol in adult patients. Methods Twenty-one patients with tooth-borne expansion (a conventional expansion screw with two premolars and two molar bands for dental anchorage [T-RME]) and the same number of patients with tooth-bone-borne hybrid expansion (a conventional expansion screw with two premolar and two molar bands for dental anchorage and four mini-implants in the palate for skeletal anchorage [H-RME]) were included. Dentoskeletal and soft tissue variables at pretreatment (T1) and after expansion (T2) were measured using posteroanterior and lateral cephalograms and frontal photographs. The sex distribution of the two groups was analysed using the chi-square test, and the change after RME in each group was evaluated using the Wilcoxon signed-rank test. Differences in pretreatment age, expansion duration, post-expansion duration, and dentoskeletal and soft tissue changes after RME between the two groups were determined using the Mann–Whitney U test. Results There were no significant differences in the expansion protocol, pretreatment conditions, and sex distribution between the two groups. Despite similar degrees of dental expansion at the crown level between the two groups, H-RME induced increased skeletal and parallel expansion of the maxilla compared to T-RME. After expansion, H-RME demonstrated increased forward displacement of the maxilla without significant changes in the vertical dimension, while T-RME exhibited increased backward displacement of the mandible, increased vertical dimension, and decreased overbite. Both groups showed significant retroclination and extrusion of the maxillary incisors without significant intergroup differences. There were no significant soft tissue changes between the two groups. Conclusion This study suggests that using skeletal anchorage in RME may induce increased skeletal and parallel expansion of the maxilla without significant effects on the vertical dimension.

Periodontal effects of maxillary expansion in adults using non-surgical expanders with skeletal anchorage vs. surgically assisted maxillary expansion: a systematic review

Objectives Describe and compare harmful periodontal effects as a consequence of maxillary expansion in adult patients with different types of anchorage devices in non-surgical expanders with skeletal anchorage and surgically assisted maxillary expansion. Materials and methods An exhaustive search was carried out on the electronic databases PubMed (MEDLINE), Embase, Cochrane and LILACS. Additionally, journal references and grey literature were searched without any restrictions. After the selection and extraction process; risk of bias was assessed by the ROB-1 Cochrane tool and Newcastle-Ottawa Scale (NOS) for randomized trials and cohort studies, respectively. Results Of 621 studies retrieved from the searches, six were finally included in this review. One of them presented a low risk bias, while five were excellent respective to selection, comparability and outcomes. Results showed that maxillary expansion in adults using non-surgical expanders (bone-borne or tooth-bone-borne with bicortical skeletal anchorage) produce less harmful periodontal effects, such as: alveolar bending with an average range from 0.92° to 2.32°, compared to surgically assisted maxillary expansion (tooth-borne) of 6.4°; dental inclination with an average range from 0.07° to 2.4°, compared to surgically assisted maxillary expansion (tooth-borne) with a range from 2.01° to 5.56°. Conclusions Although limited, the current evidence seems to show that the bone-borne or tooth-bone-borne with bicortical skeletal anchorage produces fewer undesirable periodontal effects.

Full Digital Surgery-First, Skeletal Anchorage and Aligners Approach to Correct a Gummy Smile and Class II Malocclusion with Mandibular Retrusion and Deviation

Background: The demand for interdisciplinary orthodontic treatment has increased significantly in the past few years, especially in adult patients. This kind of treatment requires careful clinical management, as consequence of the possible complications and limits related to adult age. However, the use of skeletal anchorage and three-dimensional (3D) digital technology has deeply revolutionised diagnostic planning and treatment strategies. Methods: A fully digital approach to the treatment of a Class II patient with a gummy smile and mandibular deficiency and deviation, consisting of initial surgery followed by the use of aligners and skeletal anchorage, is described. Results: The 3D, fully digital pre-evaluation enabled clinicians to accurately and reliably plan the surgical procedure and subsequent orthodontics, including the individualised positioning of stabilisation plates and a splint for maxillary and chin surgical movements. This allowed for the improvement of the patient’s facial aesthetics and dental occlusion without the use of visible orthodontic appliances or the occurrence of pre-surgical aesthetic worsening. Conclusions: This approach could be very effective for adult patients seeking aesthetic treatment options for facial and dental aesthetic improvement.

Occlusal Cant and Its Challenges – A Review

Asymmetries can be considered as a huge challenge for an orthodontist because of the complex mechanics and uncertainty in stability of treatment outcomes. Multifactorial nature of the asymmetry due to wide range has complicated the classification and determination of the cases. The aetiology can be classified as hereditary and environmental factors. The occlusal cant in patients can be evaluated by frontal photographs, lateral cephalograms, clinical assessment and a threedimensional imaging methods. Photographs can be used as one of the methods to evaluate the asymmetries of the soft tissue and also the cant of lips. In recent times with the aid of computers and different software’s like power point or keynote the use of reference lines with the software, facilitates in the analysis of the smile and the occlusal plane. The management of occlusal cant includes different treatment alternatives like orthognathic surgery, orthodontic therapy, or a combination treatment of both orthognathic surgery and orthodontic therapy. The surgical approach depends upon the awareness of the patient with the severity of cant and aesthetic problems as well as the jaw discrepancy in both vertical and sagittal directions. Orthognathic surgery creates an overall skeletal as well as soft tissue improvement including the lips. In cases with OC in anterior segment and deep - bite malocclusion a combination treatment is required. To reduce the anterior vertical height and to achieve more stable results intrusion of molars is considered using skeletal anchorage. The skeletal anchorage (miniscrews or miniplates) can be used for the correction of the cant in maxillary segment and the surgical treatment for correction of the asymmetry of the face like sagittal split osteotomy, ramus osteotomy etc. can be carried out. To achieve satisfactory outcome the clinician must examine and find the etiological factors and proper treatment planning has to be carried out based on the type of occlusal cant such that the outcome shows aesthetic smile along with good facial symmetry. KEY WORDS Occlusal Cant, Facial Asymmetry, Skeletal Asymmetry, Cant.