Ayça Arman-Özçırpıcı

Comparative evaluation of maxillary protraction with or without skeletal anchorage

INTRODUCTION The aim of this prospective clinical study was to evaluate the skeletal, dentoalveolar, and soft-tissue effects of maxillary protraction with miniplates compared with conventional facemask therapy and an untreated Class III control group. METHODS Forty-five subjects who were in prepubertal or pubertal skeletal growth periods were included in the study and divided into 3 groups of 15 patients each. All subjects had skeletal and dental Class III malocclusions with maxillary deficiency, vertically normal growth pattern, anterior crossbite, Angle Class III molar relationship, normal or increased overbite, and retrusive nasomaxillary complex. Before maxillary protraction, rapid maxillary expansion with a bonded appliance was performed in both treatment groups. In the first group (MP+FM), consisting of 5 girls and 10 boys (mean age, 10.91 years), facemasks were applied from 2 titanium miniplates surgically placed laterally to the apertura piriformis regions of the maxilla. The second group (FM) of 7 girls and 8 boys (mean age, 10.31 years) received maxillary protraction therapy with conventional facemasks applied from hooks of the rapid maxillary expansion appliance. The third group of 8 girls and 7 boys (mean age, 10.05 years) was the untreated control group. Lateral cephalometric films were obtained at the beginning and end of treatment or observation in all groups and analyzed according to a structural superimposition method. Measurements were evaulated statistically with Wilcoxon and Kruskal-Wallis tests. RESULTS Treatment periods were 6.78 and 9.45 months in the MP+FM and FM groups, respectively, and the observation period in the control group was 7.59 months. The differences were significant between the 3 groups (P <0.05) and the MP+FM and FM groups (P <0.001). The maxilla moved forward for 2.3 mm in the MP+FM group and 1.83 mm in the FM group with maxillary protraction. The difference was significant between 2 groups (P <0.001). The protraction rates were 0.45 mm per month in the MP+FM group and 0.24 mm per month in the FM group (P <0.001). The maxilla showed anterior rotation after facemask therapy in the FM group (P <0.01); there was no significant rotation in the MP+FM group. Posterior rotation of the mandible and increased facial height were more evident in the FM group compared with the MP+FM group (P <0.01). Both the maxilla and the mandible moved forward significantly in the control group. Protrusion and mesialization of the maxillary teeth in the FM group were eliminated in the MP+FM group. The maxillomandibular relationships and the soft-tissue profile were improved remarkably in both treatment groups. CONCLUSIONS The undesired effects of conventional facemask therapy were reduced or eliminated with miniplate anchorage, and efficient maxillary protraction was achieved in a shorter treatment period.

Pendulum appliances with 2 anchorage designs: Conventional anchorage vs bone anchorage

INTRODUCTION The aim of this retrospective study was to compare the dentoalveolar and skeletal effects obtained with 2 types of pendulum appliance with different anchorage designs: bone-anchored pendulum appliance (BAPA) and conventional pendulum appliance (CPA). METHODS The sample consisted of 39 patients (25 girls, 14 boys) with Angle Class II molar relationships. Correction of the molar relationship was achieved with the BAPA with palatal intermaxillary fixation screws for anchorage in the first group (n = 22) and with the CPA in the second group (n = 17). Lateral cephalograms before treatment and at the end of distalization were measured, and changes in the groups and the differences between the groups were analyzed statistically. RESULTS The average distalization times were 6.8 months for the BAPA group and 5.1 months for the CPA group. The maxillary first molars were tipped 9.1 degrees in the BAPA group and 5.3 degrees in the CPA group; the molars moved distally 4.8 mm in the BAPA group and 2.7 mm in the CPA group. Despite mesialization of the premolars and proclination of the incisors with the CPA, both premolars were spontaneously distalized, and the incisors were retruded with the BAPA. CONCLUSIONS The amount of distal molar movement was similar between the BAPA and the CPA. No anchorage loss or spontaneous distal premolar and incisor movement, which might decrease total treatment time, was seen with the BAPA.

Primary stability and histomorphometric bone-implant contact of self-drilling and self-tapping orthodontic microimplants

INTRODUCTION The aim of this study was to evaluate the primary stability and the histomorphometric measurements of self-drilling and self-tapping orthodontic microimplants and the correlations between factors related to host, implant, and measuring technique. METHODS Seventy-two self-drilling and self-tapping implants were placed into bovine iliac crest blocks after computed tomography assessments. Insertion torque values, subjective assessments of stability, and Periotest (Medizintecknik Gulden, Modautal, Germany) measurements were performed for each implant. Twelve specimens of each group were assigned to histologic and histomorphometric assessments. RESULTS The differences between insertion torque values, most Periotest values, and subjective assessments of stability scores were insignificant (P >0.05). The bone-implant contact percentage of the self-drilling group (87.60%) was higher than that of the self-tapping group (80.73%) (P <0.05). Positive correlations were found between insertion torque value, cortical bone thickness, and density in both groups (P <0.05). Negative correlations between insertion torque values and Periotest values were mostly observed in the self-drilling group (P <0.05). Positive correlations were found between bone-implant contact percentages, cortical bone densities, and insertion torque values in both groups (P <0.05). The differences between insertion torque values and corresponding subjective assessments of stability scores were different in both groups (P <0.05). CONCLUSIONS The differences in insertion torque values, Periotest values, and subjective assessments of stability scores of self-drilling and self-tapping implants were insignificant. Self-drilling implants had higher bone-implant contact percentages than did self-tapping implants. Significant correlations were found between parameters influencing the primary stability of the implants.

Palatal implant versus zygoma plate anchorage for distalization of maxillary posterior teeth

This study aimed to examine the skeletal, dental, and soft tissue effects of the implant-supported pendulum (ISP) and the zygoma anchorage system (ZAS) used for the distalization of maxillary posterior teeth. Among 30 patients showing Angle class II malocclusion, 15 patients with a mean age of 14.3±1.6 years and treated with ISP were included in the first group; 15 patients with a mean age of 14.7±2.5 years and treated with ZAS were included in the second group. The predistalization and postdistalization lateral cephalograms were analysed. Statistical evaluation was carried out using SPSS. Point A and upper incisors protruded in the ISP group, retruded in the ZAS group. Upper posterior teeth were distalized in both groups, but more in the ZAS group. Significant differences were observed between the groups for the sagittal movements of Point A, incisors, and posterior teeth. Overbite decreased in the ISP group, overjet decreased in the ZAS group, upper and lower lips retruded only in the ZAS group. Both methods provided absolute anchorage for distalization of posterior teeth, but the skeletal and soft tissue outcome and distalization obtained was greater in the ZAS group. Both methods can be used as alternatives to extraoral traction and conventional molar distalization appliances with different patient requirements.

Effects of the zygoma anchorage system on canine retraction

The aim of this study was to compare the effects of the Gjessing (PG) retraction spring used with and without the zygoma anchorage system (ZAS) on canine retraction. Thirty patients, with an Angle Class I or Class II malocclusion, whose upper first premolars were scheduled for extraction, were divided into two equal groups. Group 1 comprised maximum anchorage cases (nine females and six males with a mean age of 16 years 8 months) in which the ZAS was used to improve posterior anchorage and the PG retraction springs for canine retraction. Moderate anchorage cases (10 females and 5 males with a mean age of 15 years 5 month) were included in group 2 and canine retraction was achieved using only PG retraction springs. Study models and lateral cephalometric radiographs obtained at the initial and final stages of canine retraction were used for comparison of the groups to determine the effects of zygoma anchorage on canine retraction. All measurements were evaluated statistically using a Students t-test, 2 × 2 repeated measures analysis of variance, Bonferroni-adjusted t-test, and Mann-Whitney U and Wilcoxon tests according to the normality of the distribution of the variables. Mesial crown movement of the molars was 0.63 mm (P < 0.05) in group 1 and 1.50 mm (P < 0.001) in group 2. There was a statistically significant difference (P < 0.05) between the groups. No significant difference was observed between the groups for the rate of canine retraction or sagittal and vertical movement of the canines. The ZAS is a reliable and successful anchorage reinforcement method for canine retraction in extraction cases.

Comparison of short-term effects of mini- implant-supported maxillary expansion appliance with two conventional expansion protocols

OBJECTIVE This study evaluates the dentoskeletal effects of a mini-implant-supported maxillary expansion (MISME) appliance in comparison with two types of conventional expansion methods. METHODS Records of 42 patients with bilateral or unilateral posterior crossbite were included in this study. The patients were divided into three groups. In group 1, four miniscrews were placed to the palatal region and an acrylic expansion device was bonded on these screws. A bonded maxillary expansion appliance was used in group 2, while a banded expansion appliance was used in group 3. Measurements from cephalometric, postero-anterior radiographs, and dental casts taken before and after expansion were evaluated statistically. RESULTS ANB angle increased significantly in group 1 and 3. MISME group also showed an increase of SNA angle. Measurements regarding the vertical dimension did not change with MISME but significant posterior rotation was found in group 2 and 3. Overbite value showed a significant decrease in group 2 and 3, but remained stable in group 1. The nasal, maxillary, maxillary intermolar widths showed significant increases in all groups. The difference between MISME group and other groups in maxillary width was significant indicating more skeletal expansion in MISME group. The maxillary molars showed significant buccal tipping in group 2 and 3, while lingual tipping of molars was found in MISME group. CONCLUSIONS MISME can be a better alternative to bonded expansion particularly in patients with vertical growth patterns and lack of anchorage teeth.

Efficiency of piezosurgery technique in miniscrew supported en-masse retraction: a single-centre, randomized controlled trial

Background Piezoelectric surgery is a newly introduced technique for rapid tooth movement. However, the efficiency of this technique has not been investigated on en-masse retraction cases yet. Objective To investigate the efficiency of piezosurgery technique in accelerating miniscrew supported en-masse retraction and study the biological tissue response. In addition, to show if this technique induces a difference in dental, skeletal and soft tissue changes on lateral cephalograms, and in canine and molar rotations, besides intercanine and intermolar widths on dental casts. Design, setting, participants We conducted a randomized, single-centred, parallel-group, controlled trial, requiring upper right and left first premolar extractions on 30 patients above the minimum age of 14 years at the beginning of retraction. Interventions Piezosurgery-assisted versus conventional en-masse retraction anchored from miniscrews placed between second premolars and first molars, bilaterally. Outcomes The main outcome was the en-masse retraction rate. Secondary outcomes were gingival crevicular fluid (GCF) volume and GCF content of receptor activator of nuclear factor κβ ligand (RANKL), changes regarding cephalometric and dental cast variables, and miniscrew success rates. Randomization Accomplished with opaque, sealed envelopes. Blinding Applicable for data assessment only. Recruitment Commenced in February 2013 and ended in October 2014. Results Thirty-one patients were included in the study and divided into 2 groups of piezosurgery (n = 16) and control (n = 15). After 9.3 months of follow-up, no statistically significant difference was observed between groups for neither retraction rates (P = 0.958) nor GCF parameters (P > 0.05). Changes in lateral cephalometric and dental cast variables, and miniscrew success rates did not show significant differences either. Conclusion Based on the results of this study, piezosurgery technique was found to be ineffective in accelerating en-masse retraction, and promoting a difference in the studied GCF parameters, skeletal and dental variables. Registration The trial was not registered. Protocol The full protocol of this PhD thesis study can be accessed from tez.yok.gov.tr. Funding This work was supported by Başkent University Research Fund. No conflict of interest was declared.

Osseous outgrowth on the buccal maxilla associated with piezosurgery-assisted en-masse retraction: A case series

Piezoelectric surgery is a novel surgical approach used in orthodontic treatment for rapid tooth movement. This paper presents a case series wherein osseous outgrowths were observed in response to piezosurgery-assisted en-masse retraction. Sixteen patients requiring upper premolar extractions were treated with miniscrew-supported en-masse retraction and received minimally invasive decortication via piezosurgery. Computed tomography (CT) of the maxillary anterior region was performed to investigate the nature of the outgrowths. In 8 of the 16 patients, hemispheric or disc-shaped osseous outgrowths were observed on the sites where piezosurgery was performed during retraction. CT images revealed that these outgrowths were alveolar bone. This case series presents a previously unreported osseous response to piezosurgery-assisted tooth movement during orthodontic treatment. The response is mostly transient and is observed in 50% of the treated patients, suggesting a bone turnover that can be assessed clinically and radiographically.

Maxillary Expansion Via Palatal Mini-Implants: A Preliminary Study

ABSTRACT Objective: This study evaluates the skeletal and dental effects of a mini-implant supported maxillary expansion (MISME) appliance that applied forces directly to the maxilla. Materials and Method: Records of 9 patients (5 female and 4 male patients; mean age = 12 years 8 months) with indications of maxillary expansion were included in this study. After insertion of four miniscrews (1.6 mm in diameter, 7 mm in length), an acrylic expansion device was bonded on the screws. Two miniscrews were placed in the anterior palate bilaterally, 3–4 mm lateral to the suture and 3–4 mm posterior to the incisive foramen. Two miniscrews were placed bilaterally between the second premolar and first molar roots in the palatal alveolus. The MISME appliance was activated with a semi-rapid protocol until the desired expansion was achieved. The average treatment duration was 97.1 ± 62.2 days. Measurements from cephalometric, posteroanterior radiographs and dental casts taken before and after expansion were evaluated s...

Cortical bone strains around straight and angulated immediate orthodontic microimplants: a pilot study.

Purpose:To measure strains around orthodontic implants upon torque tightening and loading and to assess correlations between factors influencing primary stability. Materials and Methods:Self-drilling implants were placed into bovine iliac crest blocks after CT assessments. Upon bonding of strain gauges on bone adjacent to the implants, strain measurements were performed using a data acquisition system during torque tightening and 250 g orthodontic force application by elastic chains. Results:The torque required to place straight implants (12.16 N·cm) was higher than 30- to 40-degree angulated implants (9.31 N·cm) (P < 0.05). Cortical bone strain amplitudes of both implant placements were comparable (P > 0.05). Strains during torque tightening of straight (196 &mgr;&egr;) and tilted (114 &mgr;&egr;) implants were higher than those obtained during orthodontic loading (20–30 &mgr;&egr;). Despite the positive and direct relationship found between torque and torque strain output, strong correlations between other parameters could not be detected. Conclusion:Vertically aligned and 30- to 40-degree angulated immediate orthodontic microimplants are associated with low amplitude strains upon torque tightening and orthodontic loading.