Iranian Journal of Orthodontics
Volume:14 Issue: 1, Mar 2019

The sella turcica is considered an important landmark in orthodontics as it is used extensively in various cephalometric analyses be it for diagnosis, evaluation of growth or treatment results. In order to recognize deviations from the norm, one needs to be familiar with normal radiographic anatomy as well as morphologic variability. A review of the literature was conducted regarding the norms and variations in size, shape, morphology and bridging of the sella turcica as evidenced by cephalometric evaluation. Literature search was carried out using the following keywords: Sella Turcica, Sella Bridging, Sella Size and Morphology. Search engines: PubMed and Google Scholar were utilised, followed by hand search. The purpose of the review is to provide an insight into detection of subclinical and potentially pathologic conditions during regular orthodontic pretreatment assessments.

Self-ligating brackets are ligature-less brackets with the mechanical device built into them to close edgewise slot. It was claimed that self-ligating brackets (SLBs) have advantages over conventional-ligating brackets brackets (CLBs). The most claimed advantageous feature is reduced friction between the archwire and the bracket and full archwire engagement, resulting in faster alignment and space closure. Greater arch expansion with less incisor proclination, also faster ligation, reduced number of visits and less pain is mentioned as the beneficial features of SLBs in different articles. In this review article, we compared SLBs with CBs in aspect of resistance to sliding, speed of archwire ligation, quality of alignment and amount of pain during treatment base on the most recent articles published in literature. We concluded that although self-ligating brackets are proved to have some advantages over conventional brackets, but more studies are needed to discard doubts about using them, routinely.

Considering the changes in periodontal parameters after orthodontic treatment and lack of adequate evidence on the return of these parameters to normal, the aim of this study was to evaluate the time needed for recovery of periodontal parameters to normal after debonding. In this prospective study, 24 patients (21 females and 3 males) with a mean age of 18.86 ± 4.64 years were included, who were in the final stage of their orthodontic treatment and ready for debonding of orthodontic brackets. The most important inclusion criteria were: No history of periodontal problems, no extensive restorations and caries, no smoking, no systemic disorders and no calculus. In each session, the patients were given oral health instructions and then probing depth (PD), plaque index (PI), gingival index (GI) and bleeding on probing (BOP) of the first molars and central incisors of each quadrant were evaluated at the time of debonding (T1), and one (T2), two (T3) and three (T4) months later; in patients who did not return to normal status (GI ≤ 0.5, negative BOP, PD ≤ 3 mm) after 3 months, the measurements were repeated in subsequent months (up to 6 months). ANOVA followed by pairwise Tukey comparisons were used for determining differences in PD, GI, BOP and PI between the time intervals. In general, all the parameters were decreased from T1 to T4. Furthermore, comparisons between different intervals using post hoc Tukey test showed that decreases in PD of the buccal surface and proximal surface in comparison to debonding time were significant during the first and second months, respectively (P < 0.05). Interpretation of statistical data showed a significant reduction in GI after two months. BOP became negative and significantly different after one month in half of the teeth and two months in the other teeth. PI generally decreased from T1 to T4. Based on the results of this study, periodontal parameters returned to normal one to two months after debonding.

White spot lesion is considered as one of the main problems in the orthodontic treatment. Brackets used in fixed orthodontic treatment create an environment that provides enamel demineralization. The objective of the current study was to perform an in vitro study to compare different applications of fluoride supplements on enamel demineralization adjacent to orthodontic brackets and finally to understand the best supplement to recommend the patients. One hundred and twenty extracted caries-free human premolar teeth were randomly assigned into six groups: group 1: Control group, group 2: Fluoride toothpaste, group 3: Fluoride toothpaste/mouth rinse, group 4: Fluoride toothpaste/vanish, group 5: Fluoride toothpaste/gel and group 6: Fluoride toothpaste/foam. After bonding the brackets to the teeth, the fluoride supplements were applied based on each group above, except the control group. Then all the specimens were cycled for 30 days in demineralization solution for 8 hours a day, rinsed, placed in artificial saliva for 4 hours a day, brushed (except the control group), and put back to artificial saliva for 12 hours. DIAGNOdent laser fluorescence was used to quantify the demineralization changes. Significant differences existed between all fluoride-containing groups and control group. Analyses of the results showed a significant difference between control group and the rest 5 treatment groups (P < 0.001). Other significant differences were between groups 2/5, 3/5, 2/4 and 5/6 (P < 0.05). There was no significant difference among the other groups (P > 0.05). According to the results, all fluoride supplements could be used during orthodontic treatment to decrease the enamel demineralization. It has been illustrated that fluoride-containing toothpaste and mouth rinse is better than no fluoride treatment but is not effective as well as fluoride gel and varnish.

Cephalometric analyses norms and orthodontic software have been mainly developed for Caucasians. Thus, they might not be true for other ethnical groups. This study sought to determine cephalometric norms of an Iranian Kurdish population according to Steiner analysis. In this cross-sectional study, 100 lateral cephalograms of adult orthodontic patients between 18 - 30 years including 40 males and 60 females with normal occlusion and symmetrical faces were evaluated. Lateral cephalograms were traced and analyzed based on Steiner’s cephalometric parameters. Data were analyzed using SPSS. Differences between Kurdish and Caucasian norms were analyzed using one-sample t-test. Independent t-test was used to compare males and females (P < 0.05). The SNA, SNB, ANB, SND (Sella-Nasion-D point), interincisal angle, GoGn-SN L1-NB (both angular and linear measurements), SL (distance from Sella point to L, which is the projection of the most-anterior point in the body of mandible or pogonion on SN and SE (distance from Sella point to E point, which is the intersection of a line drawn from the most distal limit of the posterior surface of condyle head and SN) values were significantly different between the Kurdish population and Caucasian norms (P < 0.05). No significant differences existed in Occl-SN (occlusal plane to SN) and U1-NA (both angular and linear measurements) between the Kurdish population and the Caucasians (P > 0.05). Kurdish males and females were significantly different in terms of SND, Occl-SN, GoGn-SN and U1-NA angles, U1-NA distance and SL and SE values (P < 0.05). No significant difference existed between Kurdish males and females in SNA, SNB, ANB, interincisal angle and L1-NB (P > 0.05). Cephalometric norms for Kurdish adults are different from those of Caucasians. The norms obtained in our study can be used for orthodontic treatments and orthognathic surgeries in Kurdish population.

The mandibular foramen has often been considered as the most reliable reference point for several anesthetic and surgical procedures in the maxillofacial region. This study evaluated the position of the mandibular foramen in different skeletal classes. A total of 90 panoramic and lateral cephalometric images belonging to class I (n = 30), class II (n = 30), and class III (n = 30) patients were used for this study. The position of the mandibular foramen in relation to the anterior and posterior borders of the mandibular ramus, inferior border of the mandible, sigmoid notch and occlusal plane was determined in each panoramic radiograph. The position of the mandibular foramen relative to the occlusal plane and the sigmoid notch significantly differed among the three skeletal groups; however, no significant difference existed among the skeletal classes with regard to the position of the mandibular foramen in relation to the anterior and posterior borders of the ramus and the inferior border of the mandible. The position of the mandibular foramen tends to be lower in skeletal class II patients; therefore, it seems that lower injection heights in these patients could result in better outcomes.

Friction plays a major role during tooth movement as it takes up to 60% of the applied force, hence reducing the force available for tooth movement. Coating the surface of orthodontic wires by various techniques is being developed to improve their mechanical and biological properties. To evaluate the characteristics of nano particle coated and uncoated stainless steel, nickel-titanium, and beta-titanium wires for (1) coating stability, (2) surface characteristics and (3) biocompatibility after 21 days of exposure to artificial saliva. Six types of wires were tested for coating stability, surface characteristics before and after exposure to artificial saliva using scanning electron microscope and the artificial saliva was tested for leaching of ions by inductively coupled plasma optical emission spectrometer. Coating thickness was reduced in each group after exposure to artificial saliva which was statistically significant. Significant changes in surface morphology such as delamination and irregularity of the coating was noted. Coated NiTi wires showed lesser leaching of ions when compared with uncoated NiTi wires but the difference was not statistically significant. Coating delamination and irregularities were seen in many areas. The highest concentration of ions leached among all the groups were of iron, followed by silica.

Craniosynostosis is the result of premature fusion of one or more craniofacial sutures, in which the sutural involvement generally includes the cranial vault, cranial base, and midfacial skeletal structures. Principally, treatment of craniosynostosis syndrome is challengeable and difficult. It is essential to recognize these syndromes, their symptoms and all the therapeutic choices. Crouzon and Apert syndromes are prevalent craniosynostosis which are associated with midface deficiency, exophthalmus, skeletal class III, skull malformation and mandibular prognathism. According to the severity and type of the malocclusion found in these syndromes, there are treatment option including: Removable appliance, face mask therapy + palatal expansion, high Le Fort II surgery, segmental distraction, Le Fort III surgery and distraction ostegenesis. In the present article, we introduced diagnosis of these syndromes, their therapeutic choices and finally we also presented two craniosynostosis patients and discuss about diagnosis and treatment plan procedure of them.