Distraction Osteogenesis in the Treatment of Maxillary Hypoplasia

The aim of this chapter is to review literature reporting on the use of internal distraction osteogenesis and rigid external distraction osteogenesis and to determine the biomechanical effects of internal distractors in the treatment of maxillary hypoplasia, especially in patients with cleft lip and palate (CLP), and compare the results with non-cleft patient. The standard osteotomy used for distraction osteogenesis of the hypoplastic maxilla is LeFort I. An advancement of more than 10 mm in patients with no cleft and 6 mm in patients with CLP is beyond the limit of LeFort I osteotomy, and in such cases distraction osteogenesis for advancement of the maxilla can be used. Distraction osteogenesis (DO) is a biological process involving the formation of new bone between viable bone segments that are gradually separated by incremental traction. The external and internal usage of distraction osteogenesis in the treatment of maxillary hypoplasia in patients with cleft lip and palate is a reliable, reproducible and stable alternative method to conventional one-step LeFort I advancement techniques. Biomechanical evaluation of internal maxillary distraction osteogenesis produces mathematical results to help the surgeon and the orthodontist to understand better the therapeutic effects on the maxillofacial bones and sutures of the craniofacial system

Comparative Evaluation of Nasopharyngeal Airways of Unilateral Cleft Lip and Palate Patients Using Three-Dimensional and Two-Dimensional Methods

WOS: 000314509600003PubMed ID: 22558918Aim: Comparison of nasopharyngeal airway dimensions among UCLP patients and the control group. Materials and Methods: Computed tomography imaging data and cephalometric films of 20 patients with UCLP and 20 controls were acquired prior to treatment. Three-dimensional (3D) reconstructions of nasal, superior, middle, and inferior pharyngeal airways were carried out from dicom data, and volumes of these compartments were calculated. Nasal width and superior, middle, and inferior nasopharyngeal areas were calculated from cephalometric films. Results: The only statistically significant difference among the cleft and noncleft patients was detected in nasal volume (p < .01). Upper and middle pharyngeal airway areas were found to display significant larger areas in the noncleft group on cephalometric appraisal. Nonsignificantly larger nasal widths were measured in the cleft group. Discussion and Conclusion: Evaluation of the nasopharyngeal airways of cleft and noncleft patients was done, resulting in only the nasal region showing statistically significant difference. Our results showed significantly lower nasal volume measurements of cleft patients when compared with the healthy individuals (p < .01). This inadequacy can be interpreted as an outcome of the deficiency. The controversy among results of cephalometric appraisal and 3D imaging can be associated with superimpositions, density, and contrast inadequacies and obscured landmarks. When 2D data are compared with 3D data, the former can be insufficient and therefore deceiving. Consequently, although the radiation dose of 3D imaging systems is greater, they have the advantage of superior diagnostic outputs

Biomechanical evaluation of sagittal maxillary internal distraction osteogenesis in unilateral cleft lip and palate patient and noncleft patients A three-dimensional finite element analysis

WOS: 000341225800009PubMed ID: 24552304Objective: To compare the pattern and amount of stress and displacement during maxillary sagittal distraction osteogenesis (DO) between a patient with unilateral cleft lip and palate (UCLP) and a noncleft patient. Materials and Methods: Three-dimensional finite element models for both skulls were constructed. Displacements of the surface landmarks and stress distributions in the circummaxillary sutures were analyzed after an anterior displacement of 6 mm was loaded to the elements where the inferior plates of the distractor were assumed to be fixed and were below the Le Fort I osteotomy line. Results: In sagittal plane, more forward movement was found on the noncleft side in the UCLP model (-6.401 mm on cleft side and -6.651 mm on noncleft side for the central incisor region). However, similar amounts of forward movement were seen in the control model. In the vertical plane, a clockwise rotation occurred in the UCLP model, whereas a counterclockwise rotation was seen in the control model. The mathematical UCLP model also showed higher stress values on the sutura nasomaxillaris, frontonasalis, and zygomatiomaxillaris on the cleft side than on the normal side. Conclusions: Not only did the sagittal distraction forces produce advancement forces at the intermaxillary sutures, but more stress was also present on the sutura nasomaxillaris, sutura frontonasalis, and sutura zygomaticomaxillaris on the cleft side than on the noncleft side

THE EFFECTS OF MAXILLARY EXPANSION ON THE SOFT TISSUE FACIAL PROFILE

WOS: 000419184800001PubMed ID: 29114424Purpose: The aims of this retrospective study were to evaluate the possible changes in soft tissue facial profile induced by orthopedic rapid maxillary expansion (RME) and surgically assisted rapid maxillary expansion (SARME), and to correlate them with the underlying hard tissue alterations. Materials and Methods: 16 patients who received bone borne SARME and 25 patients who were subjected to RME using metal cast splint hyrax appliance were analyzed retrospectively. This research was conducted on lateral cephalometric radiographs taken on 2 occasions: before expansion (T1) and at the beginning of any further orthodontic treatment (T2). Investigated lateral cephalometric parameters consisted of Holdaway soft tissue measurements with some supplementary soft tissue, skeletal and dental assessments. Results: The acquisition of T2 cephalograms which conforms to the initiation of further orthodontic treatment corresponded to 83.25 +/- 3.51 days for SARME and 85.68 +/- 4.37 days for RME after the expansion was completed. The only significant change in soft tissue profile of the SARME group was a decrease in upper lip thickness (p<0.05), whereas in the RME group, decrease in soft tissue facial profile angle and increase in H angle were found to be statistically significant (p<0.05 for each). For the RME group, the changes in soft tissue facial profile angle and H angle correlated only with the changes in SNB angle (p<0.05). Conclusion: While bone-borne SARME did not seem to possess the potential to alter soft tissue profile, tooth-borne RME caused a more convex soft tissue profile related to a reduction in SNB

Comparison of stepwise vs single-step advancement with the Functional Mandibular Advancer in Class II division 1 treatment

WOS: 000392254400011PubMed ID: 27366817Objective: To compare two groups of subjects at the peak of the pubertal growth period treated with the Functional Mandibular Advancer (FMA; Forestadent, Pforzheim, Germany) appliance using either single-step or stepwise mandibular advancement. Materials and Methods: This study was conducted on 34 Class II division 1 malocclusion subjects at or just before the peak phase of pubertal growth as assessed by hand-wrist radiographs. Subjects were assigned to two groups of mandibular advancement, using matched randomization. Both groups were treated with the FMA. While the mandible was advanced to a super Class I molar relation in the single-step advancement group (SSG), patients in the stepwise mandibular advancement group (SWG) had a 4-mm initial bite advancement and subsequent 2-mm advancements at bimonthly intervals. The material consisted of lateral cephalograms taken before treatment and after 10 months of FMA treatment. Data were analyzed by means paired t-tests and an independent t-test. Results: There were statistically significant changes in SNB, Pg horizontal, ANB, Co-Gn, and Co-Go measurements in both groups (P .05). Conclusion: Because of the higher rates of sagittal mandibular skeletal changes, FMA using stepwise advancement of the mandible might be the appliance of choice for treating Class II division 1 malocclusions

Photocatalytic antimicrobial effect of TiO2 anatase thin-film-coated orthodontic arch wires on 3 oral pathogens

WOS: 000332944300015The aim of this study was to introduce antimicrobial activity to stainless steel orthodontic arch wires by coating them with TiO2 in anatase form. Stainless steel (0.016 x 0.022 inch), D-rect (0.016 x 0.022 inch), and multistranded hammered retainer wires (0.014 x 0.018 inch) were coated with TiO2 anatase by the sol-gel dip coating method. The wires were assessed for their photocatalytic antimicrobial activity against Streptococcus mutans, Candida albicans, and Enterococcus faecalis. After illumination under UVA (315400 nm) at 1.0 mW/cm(2) for 1 h, the reduction efficiencies of the anatase-coated arch wires were calculated by using colony-forming unit counts. All anatase-coated arch wires showed remarkable inhibitor effects against the test microorganisms under UVA. The most efficient wire on S. mutans was the stainless steel wire, with a 99.99% reduction in growth, but multistranded hammered retainer wire was the most active against both C. albicans and E. faecalis, with 98.0% and 91.68% reduction rates, respectively. TiO2-coated arch wires exposed to UVA illumination showed significant antimicrobial activity when compared with uncoated samples and coated, but not UVA-exposed, samples. Our results suggest that the antimicrobial effect of TiO2-coated arch wires in long-lasting orthodontic treatments would be beneficial for the prophylaxis of caries

Raised Interleukin-13 Levels in Cord Blood Increases the Risk of Allergic Sensitization at 5 Years of Age

The identification of early markers of atopy in cord blood of newborns at delivery may offer prediction of future allergic sensitization. The aim of this study was to evaluate the relationship between cord blood interleukin-13 (IL-13) and interferon-gamma (IFN-gamma) and development of allergic diseases during the first five years of life