Retrospective comparison of the number of screws used for fixation of skeletal anchorage plates in orthodontics, and their failure rates.

The aim of this study was to compare the failure rate of fixation of skeletal orthodontic anchorage plates (SAP) with two screws with that of three screws, and to find out if there is a relation between the number of screws used to fix the plates and the failure rate. We reviewed clinical records of 65 patients from five hospitals with 176 SAP, and took into account other factors that may have affected the failure. The overall failure rate was 15/176 (8.5%), and for with two-screw fixation it was 9/86 compared with 6/90 for those with three-screw fixation. Age, sex, and coexisting medical conditions did not affect the failure rate. There was a higher failure rate for those placed in the mandible (11/105) than for those placed in the maxilla (4/71). SAP provide a stable source of skeletal anchorage for orthodontic treatment. Our results show that those fixed with two screws may be marginally more likely to fail than those fixed with three, but further studies are needed to investigate the association between failure and the number of screws used.

Epidemiologic study of orthodontic retention procedures.

INTRODUCTION: The aims of this study were to survey current retention procedures applied by Dutch orthodontists and to examine their acquaintance with "unintentionally active retainers." METHODS: A questionnaire was sent to all 306 Dutch orthodontists involved in patient treatment. Questions were clustered in 4 parts: (1) general information, (2) retention procedures, (3) characteristics of wire materials for bonded retainers, and (4) acquaintance with "unintentionally active retainers." RESULTS: The response rate was 98%. The most applied retention modality in the maxillary arch was a combination of a removable and a bonded retainer (54%); in the mandibular arch, mainly a bonded retainer without a removable retainer was used (83%). Bonded retention was aimed to be lifelong for the maxillary arch (90%) and the mandibular arch (92%). Mean removable retention duration was 2 years. Vacuum-formed retainers were used more frequently and Hawley-type retainers less frequently. The wire materials used for bonded retainers were diverse. All orthodontists were familiar with unintentionally active retainers; 44% believed this phenomenon is caused by the properties of round multistrand wires. The opinion that unwanted changes in tooth position can arise due to the properties of round multistrand wire material was associated with changing the wire material (P <0.005). CONCLUSIONS: Lifelong retention with bonded retainers continues to increase. All orthodontists were acquainted with unintentionally active retainers and their impact. There is a need to identify all causative factors of inadvertent tooth movement in relation to bonded retainers and to prevent the onset of unintentionally active retainers.

Surgical difficulties, success, and complication rates of orthodontic miniplate anchorage systems: Experience with 382 miniplates.

PURPOSE: The aim of this study was to evaluate the complications and success rates of the miniplates using both maxilla and mandible for orthodontic anchorage in growing patients. MATERIALS AND METHODS: One hundred and fifty-five consecutive patients (range 8.7-13.8 years) with Class II and III malocclusion without congenital or acquired deformities were included in this study. A total of 382 titanium miniplates were placed by the same surgeon. All miniplates were inserted under local anesthesia. Loading of the miniplates with a force of 200 g with the help of elastics or functional devices were initiated 3 weeks after surgery. RESULTS: The overall success rate of miniplate anchorage in terms of stability was 96.8%. Twenty-one patients reported irritation of the mucosa of the cheeks or lower lip after the surgery in the mandible group. Twelve miniplates needed to be removed and were successfully replaced. CONCLUSION: Skeletal anchorage miniplates is effective for correcting malocclusions. Success depends on proper presurgical patient counseling, minimally invasive surgery, good postsurgical instructions, and orthodontic follow-up.

Prevalence of the use of anchorage miniscrews among French orthodontists.

Since always, anchorage has raised frequent problems for orthodontists. Since the early 2000s, the use of anchorage miniscrews has spread on a vast scale among practitioners. For the first time, a broad epidemiological survey (733 exploitable responses) has looked into the habits of French orthodontists regarding the use of anchorage miniscrews. The survey reveals that the majority of French practitioners have adopted miniscrews in their daily practice (66%), particularly among those using the lingual technique. However, the number of patients concerned still remains small for most practitioners (fewer than 10 patients for 65% of users). Seventy-four percent of users are satisfied with their experience with miniscrews although a majority uses them exclusively in adults (64%). The movements most sought by miniscrew users are mesialization/distalization and intrusion/extrusion. Among non-users, 60% have never placed an anchorage miniscrew but are thinking about doing so, whereas 20% of practitioners have used them but have since abandoned them. Finally, 20% of non-users have never used anchorage miniscrews and do not intend to do so.

British Orthodontic Society national audit of temporary anchorage devices (TADs): report of the first thousand TADs placed.

OBJECTIVE: To provide data from the British Orthodontic Society (BOS) national clinical audit on temporary anchorage device (TAD) use following the recommendations of the National Institute for Health and Clinical Excellence (NIHCE) Design and setting: The Audit commenced on 1 January 2008 and is still ongoing. This article reports the data for TADs placed from 1 January 2008 to 1 November 2013. MATERIALS AND METHODS: Audit data was collected from participants using a system of both on-line data entry and hard copy forms. The criteria and standards for the audit were set following the NIHCE report in conjunction with the Development and Standards Committee of the BOS. Virtually all participants used the on-line data entry available on the BOS website. The data submitted was checked and entered manually into an Excel spreadsheet, and transferred to SPSS for analysis. RESULTS: Written information and documented discussion of risks were provided in over 90% of TADs placed, but 17.4% were placed without a specific signed consent form. Temporary anchorage device failure rate was 24.2% overall. Among failed TADs, 93.1% were lost or removed due to excess mobility. Infection or inflammation resulting in loss or removal was reported in 6% of TADs. CONCLUSIONS: The only audit standard that was met was failures due to infection of inflammation. The rest of the audit standards were not met. Recommendations are made to address these issues.

One palatal implant for skeletal anchorage--frequency and range of indications.

OBJECTIVE: Aim of this investigation was to analyze the frequency and range of indications of orthodontic treatments using one palatal implant for skeletal anchorage, in a time frame of four years. MATERIAL AND METHODS: A sample was comprised by viewing retrospectively the patient collective of a specialized university clinic who started orthodontic treatment in the time frame 01/09-12/12. Inclusion criterion was the first application of a superstructure within the investigated period after successful insertion of a palatal implant (Ortho-System®, Straumann, Basel, Switzerland). Frequency and range of indications of the conducted skeletally anchored tooth movement were determined by analyzing the individual patient documentation such as medical records, radiographs and casts. RESULTS: From a total of 1350 patients who started orthodontic treatment in this period met 56 (=4.2%) the inclusion criterion. In 85.7% of this sample was sagittal orthodontic tooth movement conducted, most frequently mesialization of ≥1 tooth (44.6%). Vertical tooth movement was in 57.1% of the sample performed, mostly extrusion of ≥1 tooth (34%). In 33.9% of the sample was ≥1 displaced tooth orthodontically relocated. One or two upper incisors were in 16.1% of the sample permanently replaced by the superstructure, all but one even after orthodontic treatment. In 66.1% of all cases were multi-functional anchorage challenges performed. CONCLUSION: 4.2 % of all treated patients within the investigated period required orthodontic treatment with skeletal anchorage (palatal implant), mainly for performing sagittal tooth movement (mesialization). The palatal implant was primarily used for multi-functional anchorage purposes, including skeletally anchored treatment in the mandible.

Skeletal anchorage for everybody? a questionnaire study on frequency of use and clinical indications in daily practice.

AIM: The purpose of this survey was to determine how commonly, and in what clinical situations, German-based orthodontists use skeletal anchorage devices in daily clinical practice. METHOD: In early 2013, a set of questionnaires on the subject of skeletal anchorage devices was mailed to 2459 members of the German Orthodontic Society (Deutsche Gesellschaft für Kieferorthopädie, DGKFO). The questions dealt separately with mini screws (MSCs) and osseointegrated palatal implants (OPIs). The addresses were asked whether or not, as well as how frequently and in what clinical situations, they used these MSCs and/or OPIs, what their experience was, and to elaborate on their reasons for using or not using these devices. RESULTS: The rate of returned questionnaires was 48 %. To correctly interpret our data, it should be kept in mind that an unknown number of respondents did not distinguish between OPIs and palatally inserted MSCs. Overall, 62 % indicated that they did use MSCs and/or OPIs, although most of them (> 50 %) infrequently (≤ 2 new patients/3 months). Only ≤ 2 % were frequent users (> 2 new patients/week). While most users (> 70 %) indicated that their experience was mostly good, only ≤ 50 % considered the devices easy and trouble-free to use in daily clinical practice. The median percentage of insertion procedures conducted by the respondents themselves was 2 % for MSCs and 0 % for OPIs. Many of the non-users indicated that their treatment concept did not include suitable clinical indications (≥ 50 %), expressed skepticism about the success rates (56 % of MSC and 21 % of OPI non-users), or thought that the insertion procedures involved were too complex or time-consuming (33 % of MSC and 56 % of OPI non-users). CONCLUSION: A total of 62 % of German-based orthodontists participating in this survey indicated using skeletal anchorage devices, although most of them infrequently. Major reasons for non-use were lack of clinical indications, skepticism about the success rate of MSCs, and overly complex or time-consuming procedures of surgical OPI insertion.

Temporary anchorage device usage: a survey among Swiss orthodontists.

BACKGROUND: The aim of the survey was to obtain information on the treatment plan preferences, mechanics and characteristics of temporary anchorage device (TAD) application using a single case presented to orthodontists in Switzerland. METHODS: A structured questionnaire to be completed by all study participants with case-specific (treatment plan including mechanics and TAD usage) and general questions (general fixed appliance and TAD usage as well as professional, educational and demographic questions) together with an orthodontic borderline case was utilised. The case was a female adult with dental Class II/2, deep bite and maxillary anterior crowing, who had been treated in childhood with extraction of four premolars and fixed appliance followed by wisdom tooth extraction. RESULTS: The response rate was 24.4% (108 out of 443). The majority (96.3%, 104) proposed comprehensive treatment, while 3.7% (4) planned only alignment of maxillary teeth. 8.3% (9) included a surgical approach in their treatment plan. An additional 0.9% (1) combined the surgical approach with Class II mechanics. 75.1% (81) decided on distalization on the maxilla using TADs, 7.4% (8) planned various types of Class II appliances and 3.7% (4) combined distalization using TADs or headgear with Class II appliances and surgery. Palatal implants were the most popular choice (70.6%, 60), followed by mini-screws (22.4%, 19) and mini-plates on the infrazygomatic crests (7.0%, 6). The preferred site of TAD insertion showed more variation in sagittal than in transversal dimension, and the median size of mini-screws used was 10.0-mm long (interquartile range (IQR) 2.3 mm) and 2.0-mm wide (IQR 0.3 mm). CONCLUSIONS: Distalization against palatal implants and then distalization against mini-screws were the most popular treatment plans. Preferred site for TAD insertion varied depending on type and size but varied more widely in the sagittal than in the transversal dimension.

2013 survey of Australian orthodontists' procedures.

AIM: This survey of Australian orthodontists was conducted to assess treatment preferences. METHODS: Email invitations to participate in an online survey were sent to a total of 433 Australian Society of Orthodontists (ASO) members and 158 replies were received (36% response). RESULTS: For Class II treatment, most practitioners preferred to wait and treat later but when early treatment was performed, the Twin Block was the most popular appliance. For fixed appliance treatment, the 0.022 inch slot was the most commonly used (73%) and the median treatment time was 20 months. The median extraction rate was 23% which was similar to that reported in a 2008 USA survey. Sequential plastic aligners were used by 73% of respondents and Temporary Skeletal Anchorage Devices were used by 77%. The most common research question clinicians would like answered related to retention. CONCLUSION: The responses were similar Australia-wide but some areas of difference were revealed and discussed.

Temporary anchorage device utilization: comparison of usage in orthodontic programs and private practice.

AIM: There is limited data on how temporary anchorage devices (TADs) are currently used in orthodontics. The aim of this study was to survey two groups of orthodontic providers-graduate orthodontic residencies and private practitioners-about their use. METHODS: A 15-question survey was prepared and administered to all 61 accredited orthodontic residencies and an equal number of private orthodontic practitioners (all in the United States). A second survey was also included and provided to the residency programs. RESULTS: The response rate was 63.9% for private practitioners and 70.4% for orthodontic residency programs. The majority of the residency programs (82.9%) and practitioners (69.2%) reported placing TADs in their practices. TADs were placed in 6.0% of the patients treated by private practitioner and in 5.3% of patients treated in residency programs. A combination of topical and local anesthesia was the anesthetic of choice for 59.0% of private practitioners and 65.0% of orthodontic residency programs. A large majority of the private practitioners (79.0%) and orthodontic residency programs (61.9%) reported that the TADs were loaded immediately. The most frequently cited use for TADs was anterior en masse retraction. In total, 27.9% of the residency programs used miniplates, compared to 17.9% of the practitioners. CONCLUSION: Since 2005, a large number of US programs have incorporated TADs into their didactic/research curriculum and residency programs. Both mini-implants and miniplates may have a far-reaching impact on the clinical practice of orthodontics for decades to come. This survey detailed the trends and differences between practitioners and residencies in the TAD utilization experience and provided important information that is otherwise not available in the literature.

Skeletal anteroposterior discrepancy and vertical type effects on lower incisor preoperative decompensation and postoperative compensation in skeletal Class III patients.

OBJECTIVE: To determine the initial compensation, preoperative decompensation, and postoperative compensation of the lower incisors according to the skeletal anteroposterior discrepancy and vertical type in skeletal Class III patients. MATERIALS AND METHODS: The samples consisted of 68 skeletal Class III patients treated with two-jaw surgery and orthodontic treatment. Lateral cephalograms were taken before preoperative orthodontic treatment (T0) and before surgery (T1) and after debonding (T2). According to skeletal anteroposterior discrepancy/vertical type (ANB, criteria  =  -4°; SN-GoMe, criteria  =  35°) at the T0 stage, the samples were allocated into group 1 (severe anteroposterior discrepancy/hypodivergent vertical type, N  =  17), group 2 (moderate anteroposterior discrepancy/hypodivergent vertical type, N  =  17), group 3 (severe anteroposterior discrepancy/hyperdivergent vertical type, N  =  17), or group 4 (moderate anteroposterior discrepancy/hyperdivergent vertical type, N  =  17). After measurement of variables, one-way analysis of variance with Duncan's multiple comparison test, crosstab analysis, and Pearson correlation analysis were performed. RESULTS: At T0, groups 3 and 2 exhibited the most and least compensated lower incisors. In group 2, good preoperative decompensation and considerable postoperative compensation resulted in different values for T0, T1, and T2 (IMPA, T0 < T2 < T1; P < .001). However, group 3 did not show significant changes in IMPA between stages. Therefore, groups 2 and 3 showed different decompensation achievement ratios (P < .05). Group 3 exhibited the worst ratios of decompensation and stability (24% and 6%, respectively, P < .001). Anteroposterior discrepancy/vertical type (ANB: P < .01 at T0 and T1, P < .001 at T2; SN-GoMe: P < .01, all stages) were strongly correlated with relative percentage ratio of IMPA to norm value. CONCLUSIONS: Skeletal anteroposterior discrepancy/vertical type results in differences in the amount and pattern of initial compensation, preoperative decompensation, and postoperative compensation of lower incisors in Class III patients.

The use of fixed appliances in the UK: a survey of specialist orthodontists.

OBJECTIVE: To investigate the use of fixed appliances in the UK. DESIGN: Prospective postal questionnaire. SETTING: UK. PARTICIPANTS: All members of the General Dental Council Specialist List in Orthodontics still in active practice and not in training posts. METHOD: A preemptive letter of explanation was sent inviting orthodontists to participate in the survey. The questionnaire was subsequently posted to 935 specialists. Data analysis investigated differences in clinical practice related to varying provider groups, level of operator experience and geographical region. RESULTS: The response rate achieved was 66.3%. A majority of orthodontists routinely used the 0.022 inch pre-adjusted edgewise system, standard size Siamese pattern stainless steel brackets, conventionally ligated and bonded using standard etch and light cured composite. Nickel titanium and stainless steel were the most popular archwire materials. Anchorage was supported routinely by palatal and lingual arches in up to 25% and by headgear in over a third of respondents. Newer innovations showed variable popularity. Self-etching primer was used routinely by one-third of respondents with 11% use of self-ligating brackets. Banding of first molars was preferred by over 60% of clinicians. Bone screw implants were used by only 0.2% of respondents. Clinicians with less than 10 years experience used more headgear, light curing, MBT prescription and molar bonding. Operators with over 20 years experience used more chemically cured bonding, Roth prescription, banded first molars, 0.018 inch slot size and Tip-Edge(TM), with less use of headgear. Fixed appliance use differed from that reported in the US with lower use in the UK of standard edgewise and Roth systems, aesthetic, miniaturised and 0.018 inch slot brackets and rapid maxillary expansion. CONCLUSION: Most UK orthodontic specialists routinely used the 0.022 inch pre-adjusted edgewise system with standard size Siamese steel brackets bonded using standard etch and light cured composite with conventional ligation. Variations were seen between different provider groups, types of treatment funding, levels of operator seniority and geographical regions. Differences were noted particularly in the use of bracket prescription and design, types of molar attachment and anchorage control.

Effect of smoking on the failure rates of orthodontic miniscrews.

OBJECTIVE: The aim of this study was to investigate the effect of cigarette smoking on the failure rates of orthodontic miniscrews. PATIENTS AND METHODS: Our cohort consisted of 88 patients with a total of 110 orthodontic miniscrews. Based on their smoking habits, the patients were divided into three groups: the light smokers (< or = 10 cigarettes/day), heavy smokers (> 10 cigarettes/ day), and non-smokers. The light-smoker group consisted of 14 patients with 18 orthodontic miniscrews, and there were 15 patients with 19 miniscrews among the heavy smokers. The nonsmoker group contained 59 patients with a total of 73 miniscrews. RESULTS: The overall failure rate was 18.2% (n = 20). Heavy smokers revealed a significantly higher failure rate than light smokers (p = 0.005) or non-smokers (p < 0.001). No significant differences were observed between non-smokers and light smokers. Miniscrews in the heavy smoker group exhibited a significantly higher failure rate during the first 4 months after insertion than did the miniscrews in the light smokers (p = 0.008) or non-smokers (p < 0.001). CONCLUSION: Our results suggest that heavy smoking has a detrimental effect on the success rates of orthodontic miniscrews.

Survival analysis of orthodontic mini-implants.

INTRODUCTION: Survival analysis is useful in clinical research because it focuses on comparing the survival distributions and the identification of risk factors. Our aim in this study was to investigate the survival characteristics and risk factors of orthodontic mini-implants with survival analyses. METHODS: One hundred forty-one orthodontic patients (treated from October 1, 2000, to November 29, 2007) were included in this survival study. A total of 260 orthodontic mini-implants that had sandblasted (large grit) and acid-etched screw parts were placed between the maxillary second premolar and the first molar. Failures of the implants were recorded as event data, whereas implants that were removed because treatment ended and those that were not removed during the study period were recorded as censored data. A nonparametric life table method was used to visualize the hazard function, and Kaplan-Meier survival curves were generated to identify the variables associated with implant failure. Prognostic variables associated with implant failure were identified with the Cox proportional hazard model. RESULTS: Of the 260 implants, 22 failed. The hazard function for implant failure showed that the risk is highest immediately after placement. The survival function showed that the median survival time of orthodontic mini-implants is sufficient for relatively long orthodontic treatments. The Cox proportional hazard model identified that increasing age is a decisive factor for implant survival. CONCLUSIONS: The decreasing pattern of the hazard function suggested gradual osseointegration of orthodontic mini-implants. When implants are placed in a young patient, special caution is needed to lessen the increased probability of failure, especially immediately after placement.

Comparison of treatment outcomes between skeletal anchorage and extraoral anchorage in adults with maxillary dentoalveolar protrusion.

INTRODUCTION: The goal of this retrospective cephalometric study was to compare orthodontic outcomes in patients with maxillary dentoalveolar protrusion malocclusion treated with extraoral headgear or mini-implants for maximum anchorage. MATERIALS: Forty-seven subjects with Angle Class II malocclusion or Class I bimaxillary dentoalveolar protrusion were treated by retracting the maxillary dentoalveolar process by using the extraction space of the bilateral maxillary first premolars. Two anchorage systems were used. Group 1 (n = 22) received traditional anchorage preparation with a transpalatal arch and headgear; group 2 (n = 25) received mini-implants (miniplates, miniscrews, or microscrews) for bony anchorage. Pretreatment and posttreatment lateral cephalograms were superimposed to compare the following parameters between groups: (1) amount of maxillary central incisor retraction, (2) reduction in maxillary central incisor angulation, (3) anchorage loss of the maxillary first molar, (4) movements of the maxillary central incisor and first molar in the vertical direction, and (5) changes in skeletal measurements representing the anteroposterior and vertical jaw relationships. RESULTS: The skeletal anchorage group had greater anterior tooth retraction (8.17 vs 6.73 mm) and less maxillary molar mesialization (0.88 vs 2.07 mm) than did the headgear group, with a shorter treatment duration (29.81 vs 32.29 months). Translational movement of the incisors was more common than tipping movement, and intrusion of the maxillary dentition was greater, in patients receiving miniplates than in those receiving screw-type bony anchorage, resulting in counterclockwise rotation of the mandible and a statistically significant decrease in the mandibular plane angle. Cephalometric analysis of skeletal measurements in patients with low to average mandibular plane angles showed no significant difference between groups, although greater maxillary incisor retraction and less mesial movement of the first molar were noted in the mini-implant group. In patients with a high mandibular plane angle, those receiving skeletal anchorage had genuine intrusion of the maxillary first molar and reduction in the mandibular plane angle, whereas those receiving headgear anchorage had extrusion of the maxillary first molar and an increase of mandibular plane angle. In contrast to the posterior movement in the headgear group, anterior movement of Point A was noted in the mini-implant group. CONCLUSIONS: In both the anteroposterior and vertical directions, skeletal anchorage achieved better control than did the traditional headgear appliance during the treatment of maxillary dentoalveolar protrusion. Greater retraction of the maxillary incisor, less anchorage loss of the maxillary first molar, and the possibility of counterclockwise mandibular rotation all facilitated the correction of the Class II malocclusion.