To sum up, mild to moderate skeletal anterior open bites could easily be treated with Forced Eruption of impacted… Molar Intrusion Front Teeth Molars Especially in the maxilla . Although TADs may be placed into the attached gingiva (preferred, if possible) or mucosa, if the mucosa is mobile, the TAD will often eventually be covered by soft tissue, making alteration of orthodontic treatment me­chanics difficult without surgically uncovering the screw head. Maxillary molar intrusion with fixed appliances and mini-implant anchorage studied in three dimensions. Once stainless steel wires are placed, power chain is used to continue intrusion. Intrusion is a movement in orthodontics where a tooth is partially moved into the bone. Intrusion of the overerupted upper left first and second molars by mini-implants with partial-fixed orthodontic appliances: a case report. Intraorally TAD’s can be placed at various sites in the maxilla such as buccal alveolus, palatal alveolus and mid palatal region. It is the only Intrusion appliance designed with an active second molar spring to significantly intrude the second molars along with the first molars. ... S. Kuroda, Y. Sugawara, T. Deguchi, H.M. Kyung, T. Takano-YamamotoClinical use of TADs implants as orthodontic anchorage: success rates and postoperative discomfort. Randomized controlled trials (RCTs), nonRCTs (nRCTs), and retrospective studies (RTSs) investigating the stability of AOB correction treated with intrusion of maxillary, mandibular posterior teeth or both using any type of TAD were retrieved. Aims: The aim of this systematic review was to compare the effectiveness of temporary anchorage devices (TADs) and conventional segmented arches (CSAs) during incisor intrusion in adult patients with a deep bite and their adverse effects. 3725 0 obj <> endobj 0000103909 00000 n Generally made of titanium or titanium alloy, TADS are inserted through the attached gingiva or mucosa using a manual driver or, in some cases, a reduction handpiece. Intrusion is a movement in orthodontics where a tooth is partially moved into the bone. 0000104276 00000 n between 20% and 30% when using TADs for molar intrusion. Orthodontic intrusion is a common treatment practice for the correction of deep overbite and gummy smile [23][24] [25]. 0000017675 00000 n Go to Top of Page Study Description Study Design Arms and Interventions Outcome Measures Eligibility … It was 83% stable Lee 2008, Minimum 3 months retainer after molar intrusion For unilateral intrusion to correct cant of occlusion (Lee et al., 2009) To control expansion using Q helix by holding the normal side and allowing unilateral expansion (Lee et al., 2009) Adjunctive treatment when full orthodontic appliance is not required and the aim is corrects the position of single tooth. The purpose was to … 0000001376 00000 n Twitter. Aligner and TAD´s . 46 … 1. There are several modalities for intrusion but active intrusion can be achieved by temporary anchorage devices or TAD’s. Materials and Methods: The present prospective study was done on 24 patients in the age group of 15–25 years undergoing fixed orthodontic treatment. The TADs will be kept in place for the remainder of treatment to maintain the stability of the intrusion as bone remodeling occurs. Because of the efficiency and stability, upper molar intrusion using mid-palatal TAD is usually preferred. The orthodontist or surgeon can insert the TAD directly into the bone through the gingiva with a handheld driver and, most often, with the use of only topical anesthetic (3). Am J Orthod … Tipping. Designed by orthodontists specifically for orthodontic use, VectorTAS is a coordinated system of miniscrews, attachments and instruments that provide clinicians with all the benefits of temporary anchorage: … Settings and design: Four electronic databases were searched. Introduction: Temporary anchorage devices (TADs) have been shown to be effective in the treatment of VME and/or bimaxillary protrusion but literature focus has been on maxillary miniscrews and not on the efficacy of mandibular TADs. ... Nowadays, they are often called temporary anchorage devices (TADs) . 0000005811 00000 n 0000001900 00000 n 43 The Biomechanics of Extra-alveolar TADs in Orthodontics 445 Marcio Rodrigues de Almeida. 0000015715 00000 n RME Hybrid Hyrax . The Luccarelli Intruder is a fixed transpalatal appliance that utilizes TAD intrusion mechanics to close down anterior open bites. Class I buccal occlusion was established bilaterally. 0000016476 00000 n It is the only Intrusion appliance designed with an active second molar spring to significantly intrude the second molars along with the first molars. Orthodontic Correction and Periodontal Surgery ... Posterior TADs for molar intrusion & maximal retraction Palatal arch or lingual arch if necessaryActive vertical control on both arches . Buccal or palatal TADs have been used to support intrusion of the posterior teeth and correction of anterior open bite, especially in adult patients. endstream endobj startxref For those new to TADs or considering their use in practice, this workflow for TAD placement is repeatable and simple. Intrusion can be completed in many different ways and consists of many different variations. With the introduction of TADs, orthognathic surgery could be avoided for select anterior open bite cases. Introduction ... (TADs) are small titanium bone screw or stainless steel bone screws which are placed either in bu ccal alveolar bone or the palatal side. Anterior TADs for bite opening . 0000037882 00000 n Several features of this site will not function whilst javascript is disabled. If lingual TAD’s are considered, add a significant amount of expansion to counteract the lingual component in the intrusion. Miniscrew anchorage has greatly expanded the limit of clinical orthodontics. ~/��cV3F�':��u�A���� �吺9�K�sM��IF�9*�C���+3LF^��eE�Q� �qS�q��|ݿ�$#ފaO��ù����eM΍��3g�Ʈ��JtMO�9N5��TN�VX}e�>+P�M�NXH�,��6�b���L/`i7�XI���g�r��/.��b>nt@��`/R�v��e����gB j[�����;%�l69EF� h��W�n�D�%��KVP��IMj�:Q�J�w���kހ'�9c;vH�M%�Me��d���|߱����3�t`GÙ�Q0�,N$S��D�W4�+�&�8�LIZ�g�P�f�i�$�H�F�a�ή0#��痽5h���dp6a?��:K����bu��h�ė. 0000009689 00000 n VectorTAS provides clinicians with a fast, effective means to treat a full range of orthodontic cases without compensating for the inadvertent reciprocal movement of adjacent teeth. 45 Palatal and Ramal Plate Applications 467 Yoon-Ah Kook, Jae Hyun Park, and Mohamed Bayome. This chapter presents two cases of patients with vertical maxillary excess: vertical excess with anterior open bite and vertical excess without anterior open bite. The Intruder is available with a RPE screw to assist in width development during intrusion if Mar 22, 2014 - The Luccarelli Intruder is a fixed transpalatal appliance that utilizes TAD intrusion mechanics to close down anterior open bites. - Molar Intrusion Phase 2: Finishing with Aligners . %PDF-1.5 %���� Electronic databases and certain orthodontic journals were searched. TAD head design, with its .075-gauge cross-cut hole, allows for ligation of this ligature to the miniscrew. Palatal alveolar bone is a good site for TAD insertion and can be used effectively in lingual orthodontics and molar intrusion. Journal of Clinical Orthodontics, May 2009. The age range of the 20 subjects selected for the present study was between 18 and 24 years to eliminate the growth effect. showed that the relapse of the incisal overbite was 17% in the first year post deband (4). Device: Single Palatal TAD A single mini-screw inserted in the mid-palate. Regarding stability of molar intrusion by TADs. Molar Mesialization Molar Distalization Beneslider Pendulum B Mesial-Distalslider . Molar intrusion is one of the valid approaches for open bite treatment and has been quantified and documented in literature to bring about mandibular autorotation and reduction of facial convexity. endstream endobj 3726 0 obj <>/Metadata 100 0 R/PageLayout/OneColumn/Pages 3723 0 R/StructTreeRoot 3545 0 R/Type/Catalog>> endobj 3727 0 obj <>/ExtGState<>/Font<>/XObject<>>>/Rotate 0/StructParents 0/Type/Page>> endobj 3728 0 obj <>stream Even without patient compliance, miniscrews can provide stationary anchorages for various tooth movements and even make it possible to move the tooth in directions which have been impossible with traditional orthodontic mechanics. [4[ O["[�v�.6;6/ޅ���/�^`?�����f���&�f�3�W�I)�� �i&m�h���P��4@� �:} confirmed that molar intrusion with skeletal TAD anchorage is simpler and more useful than 2-jaw surgery in the treatment of patients with severe anterior open bite. TAD-based intrusion of the posterior teeth in open bite cases has been found to be considerably stable. 0000016760 00000 n Miniscrew anchorage has greatly expanded the limit of clinical orthodontics. EXAMPLE 1: DEEP BITE ADULT INTRUSION OF LOWER CUSPID TO … TAD-based intrusion of the posterior teeth in open bite cases has been found to be considerably stable. Finishing . 0000002677 00000 n 21 Written by some of the world’s leading experts in orthodontics, Temporary Anchorage Devices in Clinical Orthodontics is a comprehensive, up-to-date reference that covers all aspects of temporary anchorage device (TAD) use in contemporary orthodontics. RME Hybrid Hyrax . Orthodontic Intrusion Using Temporary Anchorage Devices Compared to Other Orthodontic Intrusion Methods: A Systematic Review ... Material and Methods: All randomized, controlled clinical trials and prospective studies that compare the use of TADs in intrusion versus alternative devices from the year 2000 to 2019 were searched using various electronic databases. 3. Subsequently TAD will be removed after use. %%EOF There are several modalities for intrusion but active intrusion can be achieved by temporary anchorage devices or TAD’s. 0000004957 00000 n ... wires. 0000036827 00000 n TAD placement and intrusion could reduce the chance of anterior TAD failure. TAD placement in the orthodontic practice. Clearly, TAD placement will be determined in part by the mechanics they’re used for. Molar Intrusion. Double arch intrusion of both maxillary and mandibular teeth is necessary when closing the mandibular plane angle, which results in favorable facial changes in vertically excessive patients. Device: Two buccal TADs Two buccal TADs inserted in the upper jaw. This would suggest e ective retention protocols . 0000002033 00000 n 35. Bowman et al. 0000002256 00000 n 51 0 obj <> endobj xref 51 54 0000000016 00000 n Finishing . Aligner and TAD´s . The posterior palate has also been described as a suitable location for miniscrew applications such as skeletal support of posterior intrusion. [7] it was until later in 1997, that Kanomi described the intrusion of … However, lower molar intrusion should be considered in several situations in the listed following figure. This case report highlights pre-prosthodontic therapy by pure molar intrusion using Temporary Anchorage Device (TAD) in an adult patient seeking prosthesis to enhance chewing efficiency. 0000105404 00000 n One segment of SS wire extended from tooth 1.2 to 2.2. With the successful intrusion of the maxillary molars, the mandible automatically rotates anteriorly, resulting in open-bite closure. The elastomeric chain was placed between hooks of the transpalatal arch and the midpalatal TAD. 0000004199 00000 n Taking a real-world approach to the subject, it covers topics ranging from diagnosis and treatment planning to the many applications and management of … 20 A transmucosal bar has been developed by Costa, Pasta and Bergamaschi to ad­dress this issue. 0000032921 00000 n Usually buccal and lingual TAD’s with elastics will support the intrusion. 0000012533 00000 n %PDF-1.3 %���� In this area, because bone is firm and abundant, pilot drilling is recommended before TAD placement. The first option was a combination of orthodontics and orthognathic surgery to address the vertical skeletal problem, using a Le Fort I osteotomy to impact the maxilla and a genioplasty for chin advancement. 0000005897 00000 n Double intrusion is treatment of choice in the more severe case where s maximal closure of the mandibular plane angle is needed. To determine the sample size, we presumed that gummy smile would be decreased by 20% after intrusion of maxillary incisors by temporary anchorage devices (TADs) compared to conventional accentuated compensating curve … 0000015616 00000 n Easy Case . 0 On the other hand, the clinical use of miniscrew anchorage includes some … TADs in Orthodontics by almuzian ... For intrusion of posterior teeth (Cousley, 2010). Written by some of the world’s leading experts in orthodontics, Temporary Anchorage Devices in Clinical Orthodontics is a comprehensive, up-to-date reference that covers all aspects of temporary anchorage device (TAD) use in contemporary orthodontics. For those new to TADs or considering their use in practice, this workflow for TAD placement is repeatable and simple. 38-40. 0000033156 00000 n The Introduction of TADs Intrusion of upper and lower incisors has been a problem for our aligner patients, since the flexibility and gentleness of the Invisalign appliance allows the posterior grip on molars and bicuspids to slip somewhat, regardless of the newest bevelled attachments we impose on them. Intrusion is a movement in the field of orthodontics where a tooth is moved partially into the bone. Difficult Case . The majority of the relapse occurs within the 1 st year after . The current study compares one of the prefabricated intrusion arches, the Connecticut intrusion arch (CIA), and the temporary anchorage devices (TADs) in their effectiveness for orthodontic intrusion. Orthodontic intrusion is a common treatment approach in managing orthodontic esthetic and functional problems, including gummy smile and deep bite. Intraorally TAD’s can be placed at various sites in the maxilla such as buccal alveolus, palatal alveolus and mid palatal region. The major concerns with this approach were its cost and the risks associated with surgery. 0000105749 00000 n TAD placement in the orthodontic practice. 7. 0000037840 00000 n This presented a low to medium level of evidence to support the hypothesis that TADs are more effective than other orthodontic intrusion techniques for intruding upper incisors and improving upper incisor to lip relation while eliminating the adverse effect of compromising vertical posterior anchorage. 0000018162 00000 n Participants are orthodontic patients with anterior open bite (AOB) malocclusion. Difficult Case . 0000015521 00000 n Experimental: Two buccal TADs Two buccal TADs for orthodontic molar intrusion. 0000105164 00000 n Step 1: Determine location. Thank Orthodontic Intrusion Using Temporary Anchorage Devices Compared to Other Orthodontic Intrusion Methods: A Systematic Review Javascript is currently disabled in your browser. 0 explanations. 0000019176 00000 n Intrusion is done in orthodontics to correct an anterior deep bite or in some cases intrusion of the over-erupted posterior teeth with no opposing tooth. Intrusion can be done in many ways and consists of many different types. However, in mid 1950s successful intrusion with light continuous forces was demonstrated. Facebook . The Intruder is available with a RPE screw to assist in width development during intrusion if Hey There, Dr. Bill V Here, Thanks for your interesting question! 0000040550 00000 n In general, most open bites can be treated within 6 months following miniscrew placement Mesialslider . h�bbd```b``^"�����/ �L`�b0{6�fg�I[��1��L��Q��� �+H2v��ւ�DW��F �?r&#�H(F���K�W� �3U 0000009311 00000 n The midpalatal area usually has a large amount of bone, which can be confirmed with a lateral cephalogram or cone‐beam computed tomography. Intrusion is completed in order to correct an anterior deep bite or in some cases, the intrusion of the over-erupted posterior teeth where there is no opposing tooth. It is the only Intrusion appliance designed with an active second molar spring to significantly intrude the second molars along with the first molars. 0000011721 00000 n In the maxilla, one TAD was inserted on the midpalatal area (diameter, 1.5 mm; length, 6.0 mm; Biomaterials, Seoul, Korea) for intrusion of the entire upper dentition. The Luccarelli Intruder is a fixed transpalatal appliance that utilizes TAD intrusion mechanics to close down anterior open bites. Wilmes B, Nienkemper M, Ludwig B, Kau CH, Pauls A, Drescher D. Esthetic … True intrusion can be completed along with methods such as Burstonian segmental arch mechanics or the use of … In the present study, orthodontic extraction therapy was combined with maxillary extra-alveolar TADs in the treatment of all VME patient-subjects. The Intruder is available with a RPE screw to assist in width development during intrusion if 5�&�G��D�(NY��ؑ����s��)�V�$ %�z���1��]o���\Κ��U Resolving Orthodontic Problems P. Salehi, S. Torkan and S.M.M. REFERENCE 1. Orthodontic Correction and Periodontal Surgery ... Anterior TADs for incisor intrusion Posterior TADs for molar intrusion & maximal retraction Palatal arch or lingual arch if necessaryActive vertical control on both arches . Closed method of Anterior TADs . 44 A New and Innovative TAD System for Improved Stability and Versatility 455 Carlos Villegas and Flavio Uribe. 10,11 From a biomechanical perspective, to intrude the entire maxillary dentition, the appliance design should allow the application of force vectors of different magnitudes in multiple directions. 0000014062 00000 n Alternative treatments are as follows: (1) Reduction of the crown height of the second right maxillary molar or an extraction of the maxillary left first, second, and third molars to create space surgically for prosthesis rehabilitation (2) An intrusion of the maxillary molars with the fixed appliance of the maxillary molars in both sides, using TADs (3) Intruding maxillary molars with the fixed appliance of the … Aligner and TAD´s . The vertical disparities manifests either as deep overbite or open bite and the skeletal and dentoalveolar component defining the discrepancy are subjected to a myriad of arrangement. Shorter treatment times and less root resorption were found in the TAD group. 0000008557 00000 n Toru Deguchi, et al, Comparison of the intrusion effects on the maxillary incisors between implant anchorage and TAD's or Titanium mini-screws are used for different reasons in orthodontics. Molar Mesialization Molar Distalization Beneslider Pendulum B Mesial-Distalslider . Recently, the minimally invasive placement of temporary anchorage devices (TADs) has allowed orthodontists to treat some of these patients without orthognathic surgery through intrusion of the posterior maxillary molars. [ 10 ] An 0.019 × 0.025-inch stainless-steel wire with an accentuated curve of Spee was inserted. Torqueing. Temporary anchorage devices (TADS) have the greatest effect on which orthodontic movement? … True intrusion can be done with methods such as Burstonian segmental arch mechanics or the use of TADs anteriorly. In such cases orthodontic intrusion of the supraerupted molar can be considered. TADs have opened up a new era in the management of severe dentofacial deformities, in which surgery had been the only option. Regarding stability of molar intrusion by TADs. 2004;74(4):550-7. The posterior palate has also been described as a suitable location for miniscrew applications such as skeletal support of posterior intrusion. such cases orthodontic intrusion of the supraerupted molar can be considered. 0000007095 00000 n Single Palatal TAD for orthodontic molar intrusion. Databases used include Pubmed, … Anterior TADs for bite opening . Outcome Measures. TAD • A TAD can be defined as a device that is temporarily fixed to the bone for the purpose of enhancing orthodontic anchorage either by supporting the teeth of the reactive unit (indirect anchorage) or by obviating the need for the reactive unit altogether (Direct anchorage), which is subsequently removed after use. The TAD or Temporary Anchorage Device, is an incredibly useful innovation in orthodontics. Forced Eruption of impacted… Molar Intrusion Front Teeth Molars Especially in the maxilla . PlumX Metrics Treatment of the vertical dimension of the face is one of the most challenging areas in orthodontics. 42 Insights to Extraradicular Bone Screw Applications for Challenging Malocclusions 433 Chris H. Chang, Joshua S. Lin, Hsin-Yin Yeh, and W. Eugene Roberts. Molar intrusion of overerupted teeth can be done using miniscrew implants which serves as a promising technique, especially in adult patients. Intrusion. Even without patient compliance, miniscrews can provide stationary anchorages for various tooth movements and even make it possible to move the tooth in directions which have been impossible with traditional orthodontic mechanics. j�ۦW&k�'�,M5�!�g��U�������l ��n3l��&S_��. Placed in either alveolar or extra-alveolar bone for the purpose of providing orthodontic anchorage, temporary anchorage devices (TADs) are removed once they complete their function in the treatment regimen. The TAD can be loaded immediately as it gains its anchorage through mechanical gripping of bone rather than through osseointegration (3). In this case, the cemented appliance with power arms and the … Canine Retraction, Anterior Retraction, and Simultaneous Intrusion The design consisted of three segments of wires. 0000099472 00000 n Mesialslider . Ortho Procedures - Orthodontic Intrusion. TAD’s can be placed and supported by elastics or chain to intrude posterior teeth in combination with an aligner system. Intrusion of maxillary anterior teeth with significant reduction of overbite by orthodontic treatment is one of the approaches used to improve high smile line. treatment. 0000013490 00000 n 0000002168 00000 n The data presented in this study were collected from orthodontic records taken for 20 patients who sought orthodontic treatment in the Department of Orthodontics. 0000010454 00000 n 2. In terms of stability of anterior open bite treatment using TADs to intrude the posterior maxillary teeth, a study by Baek et al. ... Molar intrusion using TADs: The key element to correcting anterior open bite … Supraerupted maxillary first molars can be intruded 3 to 8 millimeters in 7.5 months (approximately 0.5-1.0 mm per month), without loss of tooth - Molar Intrusion Phase 2: Finishing with Aligners . placement and biological response of orthodontic TADs. Intrusion is completed in order to correct an anterior deep bite or in some cases, the intrusion of the over-erupted posterior teeth where there is no opposing tooth. Relative Intrusion. 0000006861 00000 n Explanations are useful to guide through learning process and confirm that the correct answer is indeed correct. 0000105685 00000 n These ... much as 6 mm. The advent of temporary anchorage devices (TADs) has allowed for orthodontic movements previously thought to be very difficult or impossible. Hooks were extended on the wire distal to the lateral incisor brackets to reach close to the center of resistance of the anterior segment. Usages for TADs. Results.TAD-supported molar intrusion is controlled and timely and may be accomplished without the need for full-arch brackets and wires. Easy Case . These patients will be treated by molar intrusion achieved using one of two interventions, either orthodontic fixed appliances incorporating a single palatal Temporary Anchorage Device (TAD) or orthodontic fixed appliances incorporating two buccal TADs It was 83% stable (Lee 2008), Minimum 3 months retainer after molar intrusion. Roeinpeikar Orthodontic Research Center, Shiraz University of Medical Sciences, Sh iraz Iran 1. 3760 0 obj <>stream In conclusion, this case demonstrates the profound and exciting application of skeletal anchorage to modify growth of the maxilla in the vertical plane of space, reduce gingival display while maintaining ideal occlusal relationships. Only registered users can add explanations. Similar questions: No similar questions. Intrusion, in orthodontic history, was initially defined as problematic in early 1900s and was known to cause periodontal effects such as root resorption and recession. 0000015464 00000 n 27 Another alternative is the palatal alveolus between the maxillary first molar and second premolar, where the favorable position of the first molar's palatal root and the buccal angulation of the second premolar provide excellent access for direct insertion of a … In addition, articles were manually searched for using the reference lists of relevant articles, grey … TADs may be used in addition to braces or Invisalign, so that orthodontists are able to provide simple non-surgical solution to challenging orthodontic cases. 41 Orthodontic Treatment of TMD Patients with Posterior Intrusion Using TADs 415 Gye-Hyeong Lee, Sang-Mi Lee, Sun Kyong Yoo, and Jae Hyun Park . Angle Orthod. Yao CC, Lee JJ, Chen HY, Chang ZC, Chang HF, Chen YJ. trailer <]>> startxref 0 %%EOF 104 0 obj<>stream 0000005863 00000 n This … Aligner and TAD´s . Closed method of Anterior TADs . h�b```a``������>�A��؀�����Az�Bb����Z�f'�~\a}�� Sxt��`��Ƽ�x�����tj��,V���$�j�gڶ7��u�^���D� �ҶlZ�[���GK���qd�:�:����2���nlGGCG�� ����!�(X�k�������b+��y��,��0�a�e�ɘǘ���ў!�����K�a]Bæ���@�O�ؿ��������ͦ��3���M�g TADs placed in the upper buccal segment was used for retraction and a TAD placed in the maxillary midline was used for intrusion and controlling the rotation of the maxillary plane during retraction. TADs in Orthodontics by almuzian. TADs reduce the orthodontic treatment period, minimize the discomfort during treatment, favor aesthetics, and increase the predictability of the final result. Patients hesitate to undertake surgical interventions for dento-skeletal problems. 0000023064 00000 n (C) Post-treatment photographs demonstrate significant improvement in the overjet and overbite with concomitant changes in the facial appearance. 3747 0 obj <>/Filter/FlateDecode/ID[<48052EDDE9972C4C85649D08FE9DB8ED><2AEB1644322E38479C507EC24AF58DF2>]/Index[3725 36]/Info 3724 0 R/Length 107/Prev 999050/Root 3726 0 R/Size 3761/Type/XRef/W[1 3 1]>>stream 0000010753 00000 n 0000016825 00000 n 0000007525 00000 n 0000003442 00000 n 0000098647 00000 n 0000006445 00000 n 0000050259 00000 n 41 Orthodontic Treatment of TMD Patients with Posterior Intrusion Using TADs 415 ... 43 The Biomechanics of Extra-alveolar TADs in Orthodontics 445 Marcio Rodrigues de Almeida. The advent of temporary anchorage devices (TADs) has allowed for orthodontic movements previously thought to be very difficult or impossible. Results.TAD-supported molar intrusion is controlled and timely and may be accomplished without the need for full-arch brackets and wires. 0000014719 00000 n Extrusion. 0000046104 00000 n If only lower incisors need intrusion, one TAD is placed in the midline to aid in correction. placement and biological response of orthodontic TADs. The extent and complexity of the anterior open bite will determine the amount of molar intrusion time that is neces-sary for successful treatment.