Correction of a true full-cusp unilateral posterior crossbite using mini-screw assisted biomechanics in an adult hyperdivergent patient.

Correction of a true unilateral posterior crossbite concurrent with space closure in the same dental arch side in an adult patient is demanding due to the potential iatrogenic biomechanical side effects on the contralateral unaffected side. The current case treatment strategy was aimed to manage the true unilateral posterior crossbite and space closure with minimal dentoalveolar undesirable effects by innovative application of a custom-made TAD (temporary anchorage device)-based palatal expander. In the present case report, non-orthognathic treatment of an adult female with unilateral upper right side true posterior crossbite is discussed. The patient revealed excessive gingival show at smile and upper midline deviation to the left side. The patient had also a previous history of first molar extraction on the crossbite side. The treatment was conducted by correcting the unilateral crossbite and space closure in the upper right side by using an innovative custom-made modification of hyrax anchored on TADs. Correction of the true full cusp unilateral crossbite, space closure, and midline deviation was accomplished. The patient's satisfactory aesthetic and occlusal results were obtained in 26 months with no undesirable complications in the opposite arch side. Innovative application of the miniscrew-based biomechanics could facilitate challenging treatments such as unilateral full cusp crossbite in adults with optimal final occlusal and aesthetic results and minimal undesirable complications.

Retreatment of an orthognathic camouflaged case by total lower arch mesialization using temporary anchorage device.

Mandibular tooth extractions for camouflage treatments in borderline Class III patients may end up with unpleasing esthetic results which may lead the patient seeking further complicated retreatments. In this case report, we presented a patient's retreatment with a combined orthodontic and orthognathic surgery treatment plan. The treatment strategy involved an innovative temporary anchorage device (TAD)-based method for total mandibular arch mesialization instead of space reopening for first lower premolar replacement with implants. In the current case report, orthognathic management of a Class III adult female is discussed. The patient had a history of an esthetically unsuccessful previous camouflaged orthodontic treatment with two lower premolar extractions. She was prepared for orthognathic surgery using an innovative custom-made sliding jig based on miniscrews for total mandibular arch mesialization with the aim of dental arch decompensation. After gaining the optimal dental arch discrepancy, the patient had orthognathic surgery (maxillary advancement and mandibular setback and advancement genioplasty). Total mandibular dental arch mesialization with the aim of dental arch discrepancy preparation was successfully conducted using TADs. By means of the innovative miniscrew-anchored sliding jig, the patient's satisfactory esthetic and occlusal results were obtained in 22 months. With innovative application of the miniscrews, more practical and reasonable alternatives are available to replace conventional and complicated treatment plans such as space reopening for implants in patients with unsuccessful previous orthodontic therapies.

Correlation between maxillary cuspid impaction with available space and anomalies of maxillary lateral incisors.

BACKGROUND: Association of cuspid impaction with adjacent lateral incisor anomalies is under controversy. The aim of this study was to investigate the correlation between maxillary cuspid impaction with dental anomalies. MATERIAL AND METHODS: In this in vitro experimental study, the material consisted of pretreatment dental records of 102 patients with at least one palatally or buccally displaced impacted permanent cuspid (palatal and buccal impaction groups). They were matched with a comparison control group of 102 patients having normally erupted maxillary cuspids. Available space, mesiodistal dimensions of teeth, and morphologic parameters of lateral incisors were measured using the digital caliper. Comparison of mean values of lateral incisors anomalies and severity of crowding between different groups were performed using the one-way ANOVA test, and the analysis of associations between position of the impaction and anomaly of the lateral incisors and severity of crowding was performed using the Chi-square test. P < 0.05 was considered statistically significant. RESULTS: There was no statistically significant difference in the arch length-tooth size discrepancy between the cuspid impaction groups and control group. The impaction group (buccal or palatal) presented statistically significant differences in terms of anomalies of maxillary lateral incisor compared to the control group. Peg-shaped lateral incisor was related to buccal cuspid impaction and microdontia had relationship with palatal cuspid impaction. CONCLUSION: There is the relationship between cuspid impaction and adjacent lateral incisor abnormality, but no difference was observed between buccal and palatal cuspid impactions. Crowding revealed no relationship with cuspid impaction (buccal or palatal) in this study.

Mandibular Setback as an Adjunctive Strategy for Reconstruction after Tumor Resection: A Technical Note and Case Report.

Mandibular defects due to surgical resection of pathologies are common challenges for maxillofacial surgeons. In some clinical situations, alteration or combination of different surgical procedures is needed to reduce the size of bony defects and improve the success rate of bone grafts. In the current study, an 18-year-old female with a pathological lesion (ameloblastoma) in the mandible is presented. After tumor resection, bony defect reconstruction with autogenous bone graft was combined with a mandibular setback to facilitate the procedure. In this case, the simultaneous combination of orthognathic mandibular setback movement with tumor resection in a single surgical session helped to reduce the bony defect size. The adoption of this approach led to a decrease in the volume of graft harvesting and improved the success rate of the grafting procedure.

Bond Strength of an Orthodontic Adhesive Containing an Antibiofilm Agent (Octafluoropentyl Methacrylate).

OBJECTIVE: The objective of this study was to determine whether an adhesive containing antibiofilm agent octafluoropentyl methacrylate (OFPA) has an acceptable bond strength as an orthodontic adhesive. METHODS: Sixty human premolars were divided into four groups. In Groups 1 and 2, brackets were bonded to the teeth using experimental nanohybrid adhesive containing OFPA (ENH-OFPA) and Transbond XT (TXT) was used in Groups 3 and 4. In Groups 1 and 3, the samples were stored in water at 37°C for 24 h and in Groups 2 and 4 thermocycled between 5°C and 55°C. The entire samples were debonded utilizing a universal testing machine. Two-way ANOVA test employed to compare the shear bond strength (SBS) between two adhesives. Independent Student's t-test was utilized to compare the SBS at 24 h and followed thermocycling in each adhesive group. Adhesive remnant index (ARI) evaluated in different groups using Chi-square test. RESULTS: The mean value for SBS in ENH and TXT groups were 8.13 MPa and 8.10 MPa, respectively. The inference of P = 0.260 was observed and concluded to be nonsignificant for adhesives in terms of SBS. Statistically, differences that observed in SBS at 24 h and following thermocycling in TXT (P = 0.288) and ENH-OFPA (P = 0.145) groups did not consider to be significant. Comparing ARI scores with bracket failure mode resulted in no significant difference (P = 1) between two adhesives in both 24 h and following thermocycling. CONCLUSION: Adding OFPA does not compromise SBS of the experimented orthodontic adhesive.

Cervical Dentin Changes in Curved Root Canals after Using WaveOne and Reciproc Files with Full Rotation versus Reciprocation Movement: An Ex vivo Study.

AIM: The aim of the current study was to compare the effect of WaveOne and Reciproc files in reciprocation versus reverse full rotation movements on cervical dentin thickness by virtue of cone beam computed tomography (CBCT) analysis in curved mesial canals of mandibular first molars. METHODS: Mesiobuccal canals of 60 mandibular molars were randomly divided into 4 groups (n = 15): Group 1; WaveOne/Reciprocation, Group 2; WaveOne/Full-Rotation, Group 3; Reciproc/Reciprocation, and Group 4; Reciproc/Full-Rotation. Pre- and post-instrumented CBCT scans were prepared for assessment of cervical dentin thickness changes (2 mm, 4 mm below the highest point of the root furcation) in both groups. Data statistically analyzed using two-way ANOVA test. RESULTS: There was no statistically significant difference between four experimental groups in terms of remaining dentin thickness at 2 and 4 mm levels below the highest point of the furcation (P > 0.05). No separation of instruments occurred in any group. CONCLUSION: WaveOne and Reciproc files with two different motions have similar effects on cervical of root canals in terms of dentin thickness changes.

Alterations of the Danger Zone after Preparation of Curved Root Canals Using WaveOne with Reverse Rotation or Reciprocation Movements.

INTRODUCTION: The aim of this study was to compare the changes that occur in the danger zone (DZ) after preparation of curved mesiobuccal (MB) canals of mandibular first molars with WaveOne instruments in two different movements [reciprocation (RCP) and counter-clockwise rotation (CCWR)] by means of cone-beam computed tomography (CBCT). METHODS AND MATERIALS: MB canals of 30 mandibular molars were randomly divided into 2 groups (n=15); WaveOne/RCP and WaveOne/CCWR. Pre- and post-instrumentation CBCT images were assessed for changes in the dentin thickness in DZ (2 and 4 mm below the highest point of the root furcation) in both groups. Data was analyzed using the repeated measures ANOVA test. RESULTS: There was no statistically significant difference between two experimental groups in terms of remaining dentin thickness at 2 and 4 mm levels below the highest point of the furcation (P>0.05). CONCLUSION: The efficacy of WaveOne instrument on changes of the dentin thickness in the DZ was not affected by different file movements.

The Impact of Three Different Canal Lubricants on Fracture, Deformity and Metal Slivering of ProTaper Rotary Instruments.

INTRODUCTION: The aim of this in vitro study was to evaluate the effect(s) of three canal lubricants i.e. sodium hypochlorite, RC-Prep as the paste form of ethylenediaminetetraacetic acid (EDTA) and aqueous EDTA on the occurrence/incidence of fracture, deformity and metal slivering of ProTaper rotary instruments. METHODS: A total of 120 mesial canals (i.e. mesiobuccal and mesiolingual) of first mandibular molars or buccal canals (i.e. mesiobuccal and distobuccal) of first maxillary molars, with curvatures of 10-20 degrees were selected and randomly divided into three groups of forty samples each. These selected canals all had approximate 19-21 mm working length and apical diameter equal to a #15 K-file. In each group, the root canals were prepared using ProTaper rotary instruments with an electric motor using one of the three aforementioned irrigants. Subsequently, samples were compared to each other at different magnifications (16×, 20×, 40× and 57×) for any fracture, deformity or metal slivering, by the Cox regression analysis. RESULTS: The fractures rate of samples in RC-Prep group was significantly higher compared to other groups (P=0.01). No evidence of instrument deformity was detected in any groups. A statistically significant reverse relation between metal slivering and instrument fracture was observed. CONCLUSIONS: Application of aqueous EDTA and/or sodium hypochlorite as intracanal lubricants caused less fracture of ProTaper instruments compared to canal lubrication with RC-Prep.