Does Gender Have an Effect on Craniofacial Measurements?

OBJECTIVE: The aim of this cross-sectional study was to evaluate craniofacial structures in terms of different sagittal relations and gender in adolescent individuals. METHODS: Pre-treatment dental models, lateral cephalometric, and hand-wrist radiographs of 223 adolescent subjects (102 male, 121 female) were evaluated. Subjects were divided into the Angle Class I, II, and III (skeletally) subgroups according to the ANB angle. Four angular and 33 linear measurements were used to evaluate the lateral cephalometric radiographs relative to the R1 and R2 coordinate system. The Kolmogorov-Smirnov test was performed to assess the normal distribution of the data. The independent samples t-test and Mann-Whitney U test were used for the comparison of male and female subjects in each group. The values were considered statistically significant at p<0.05. RESULTS: The vertical facial dimension was found to be significantly greater in Class I male subjects than in female subjects (SGo, p=0.023; ANS-M, p=0.036), and there was a protrusive maxilla (R2ANS, p=0.038; R2A, p=0.016), while the mandibular sagittal position and the mandibular dimension were similar. The maxilla was placed protrusively (R2ANS, p=0.001; R2A, p=0.002), while the mandible was found to be larger both in the position and dimension (CoGn, p=0.003; R2M, p=0.014) in Class II male subjects. Class III male and female subjects were found to have similar maxillary and mandibular vertical and sagittal location and dimensions. CONCLUSION: Class I and II subjects showed more gender variation than Class III subjects. The gender-related results of this study declare that treatment planning of malocclusions should be based on gender differences rather than general treatment procedures, which will be useful in achieving successful orthodontic treatment results.

Peer Assessment Rating (PAR) Index as an Alternative for Orthodontic Treatment Need Decision in Relation to Angle Classification.

OBJECTIVE: This study aimed to determine cut-off points for the Peer Assessment Rating (PAR) index in relation with Angle classification to use as an alternative index for the treatment need assessment. METHODS: This study included 607 orthodontic patients aged between 9 and 18 years. Angle classification, PAR, and dental aesthetic index (DAI) scores were determined. The DAI was used as the gold standard to evaluate the subjects for treatment need. The receiver operating characteristics (ROC) analysis was used to evaluate the PAR index in relation to treatment need assessed by DAI. RESULTS: The mean PAR scores for Class I, II, and III malocclusions and total sample were 17.54, 14.27, 18.7, and 20.04, respectively. The areas under the ROC of PAR scores in relation to the DAI assessment were found as 68.3% for the total sample, 66.6% Class I, 59.2% Class II, and 71.3% Class III malocclusions. For the total sample, the optimum cut-off PAR score was 14 in relation to DAI assessment. The cut-off scores for Class I, II, and III malocclusions were 13, 11, and 16, respectively, but considering psychosocial aspects, the recommended score is 14 for Class III. CONCLUSION: The PAR index can be considered to have an acceptable level of validity for the assessment of orthodontic treatment need regarding Angle classification.

Differential Benefit of Two Different Tooth-Borne Rapid Maxillary Expansion Appliances in Female Subjects.

OBJECTIVE: The aim of the present study was to evaluate the effects of tooth-borne acrylic-bonded rapid maxillary expansion (RME) appliances with or without the anterior teeth anchorage on the skeletal and dentoalveolar structures, as well as soft tissues. METHODS: This study included 44 patients who were treated with two different tooth-borne bonded acrylic RME appliances. Lateral cephalometric radiographs were taken before the treatment (T0) and in the post-retention (T1) phase of the RME treatment. The posterior-bonded RME appliance group and full-bonded RME appliance group were created as the two different groups of treatment. The following statistical analyses were performed: intra- and inter-group comparisons were made using the paired t-test, Wilcoxon test, independent t-test, and Mann-Whitney U-test for normal and non-normal distribution data. RESULTS: Significant increases were observed in R1-A, R1-ANS, R1-U1, R1-AR, R1-St, R1-Li, and R1-Pn in both groups. R1-PNS, R1-Ls, R1-Sn, and R1-B' were found to be significantly larger at T1 than at T0 in the posterior-bonded RME appliance group. R2-A, R2-ANS, R2-L1, R2-A', and R2-Pn were significantly larger at T1 than at T0 in the full-bonded RME appliance group. The R2-A' was significantly different between the groups. CONCLUSION: The soft tissue A point appears to be the most important differing matter between the two different RME appliances, and a full acrylic-bonded RME appliance may be beneficial for subjects with a maxillary retrognathic profile.

Nanosilver coated orthodontic brackets: in vivo antibacterial properties and ion release.

INTRODUCTION: Silver nanoparticles are currently utilized in the fields of dentistry. The aim of this study was to evaluate the antibacterial properties and ion release of nanosilver coated orthodontic brackets compared to conventional brackets. METHODS: Nanosilver coating process was applied to standard orthodontic brackets placed on the mandibular incisors of Wistar Albino rats in the study group and conventional brackets in the control group. Dental plaque, mucosal vestibular smears, saliva, and blood samples were collected from rats at various days. The amounts of nanosilver ions in blood and saliva were measured and microbiological evaluation was made for Streptococcus mutans. For testing cariogenicity, all rats were sacrificed at the end of 75 days under anaesthesia. Teeth were stained using a caries indicator, then the caries ratio was assessed. RESULTS: Nanosilver coated orthodontic bracket favoured the inhibition of S.mutans on Day 30 and reduction of caries on the smooth surfaces. The nanosilver amounts in the saliva and serum samples were significantly higher in the study group on Day 7. CONCLUSION: It is suggested that nanosilver coated orthodontic brackets, as an antibacterial agent without patient compliance, could be helpful for the prevention of white spot lesions during fixed orthodontic treatment.

Biocompatibility of nanosilver-coated orthodontic brackets: an in vivo study.

BACKGROUND: Nanosilver particles of which antibacterial and antifungal properties have been shown in various in vitro and in vivo studies are used in many medical and dental fields for the prevention of infection. In this study, it is intended to evaluate the biocompatibility of nanosilver-coated brackets. METHODS: Nanosilver coating process was applied to the standard orthodontic brackets by a physical vapor deposition system. Brackets were coated with nanosilver particles of 1 µ thickness. A total of 12 Wistar Albino rats were included in the study (six) and control (six) groups. For the study and control groups, four nanosilver-coated and four standard brackets were aseptically implanted subcutaneously in the dorsal region of each rat. The brackets were removed with the surrounding tissues on days 7, 14, 30, and 60. The specimens were evaluated for inflammatory response. RESULTS: No significant difference was found in terms of tissue reaction between the study and control groups. On day 7, randomly distributed brown-black granules were seen in the granulation tissue adjacent to the bracket in the study group. These foreign particles continued along the bracket cavity in a few samples, but the inflammatory response was insignificant between the groups. Mast cell count was found to be significantly smaller only on day 7 in the study group than in the control group. CONCLUSIONS: Nanosilver-coated orthodontic brackets were found to be similar with the standard type concerning inflammation. Further researches are needed with regard to the assessment of the brown-black granules, especially on the deposition of the vessel walls.

Prevalence of Posterior Crossbite for Orthodontic Treatment Timing.

OBJECTIVE: To evaluate the prevalence and distribution of posterior crossbite in different dentition stages in a Turkish sample. STUDY DESIGN: 1554 subjects (843 girls, 711 boys) aged 4-25 years were evaluated to determine the prevalence of posterior crossbite in a Turkish sample. The subjects were classified according to four dentition stages (primary, early mixed, late mixed and permanent) and transversal occlusal status. The statistical evaluation was done by Chi-square, Fischer exact tests. RESULTS: Bilateral and unilateral crossbite on the right and left sides had the highest frequency in the permanent dentition (51.0%, 47.3%, and 53.6%; respectively). No significant differences were found between unilateral (right and left) and bilateral crossbite with regard to dentition stages. No significant differences were found between unilateral right or left side posterior crossbite with regard to dentition stages. CONCLUSION: An increasing trend in the prevalence of posterior crossbite was observed from the primary dentition towards permanent dentition in this study.

A Comparison of Three Orthodontic Treatment Indices with Regard to Angle Classification.

OBJECTIVES: To calculate the agreement between the Dental Aesthetic Index (DAI) and the Index of Complexity, Outcome and Need (ICON) in assessing orthodontic treatment need and to determine correlations between the Peer Assessment Rating (PAR) and DAI and ICON scores according to Angle classification among patients referred for orthodontic evaluation. STUDY DESIGN: This study included 457 randomly selected patients between 9 to 17 years of age. Patients were divided into four groups according to Angle classification [Class I (n=154), Class II division 1(Class II/1) (n=155), Class II division 2(Class II/2) (n=52) and Class III (n=96)]. Relationships between PAR scores and ICON and DAI scores were evaluated with the Spearman correlation test. Unweighted kappa statistics were used to analyse agreement between the ICON and DAI on the need for treatment, according to Angle classification. RESULTS: Class I malocclusions scored significantly lower than other Angle classifications in all indices. Both the ICON and DAI showed significant positive correlations with the PAR in the general study population. For Class II/2 patients, no correlation was found between PAR and DAI scores. There was significant agreement between the ICON and DAI on treatment need among Class I, Class II/1 and Class II/2 patients however, no agreement was found for Class III malocclusions. CONCLUSIONS: The ICON, DAI and PAR produce similar results and can be used interchangeably for the general orthodontic patient population. However, based on Angle classification, prominent differences exist in scoring certain occlusal features.

Histomorphometric evaluation of the effects of various diode lasers and force levels on orthodontic mini screw stability.

OBJECTIVE: The purpose of this study was to evaluate the effects of different laser dose and force levels on the stability of orthodontic mini screws used for anchorage, by histomorphometric analyses. BACKGROUND DATA: Low-level laser therapy speeds up blood flow, improves the mechanism of the revitalization processes, reduces the risk of infection, boosts metabolic activities, and accelerates the healing of the damaged tissue. Although there are many research studies about low-level laser therapy applications in a variety of areas, no investigations were found concerning mini screw stability using various laser dose levels with different force level applications. METHODS: Seventeen New Zealand white rabbits were used. A total of 68 cylindrical, self-drilling orthodontic mini screws were threaded at the fibula. Experimental subjects were divided into six groups; force application was not performed in the first three groups, whereas 150 g of force was applied via nickel-titanium closed-coil springs placed between two mini screws in the other three groups. Measurements of the initial torque values (10 Ncm) were manipulated by a digital portable torque gauge. Various low-level laser doses were applied to the groups during the postoperative 10 days. After 4 weeks, bone-to-implant contact and cortical bone thickness were histomorphometrically analyzed. RESULTS: In the 150 g force plus 20 J/cm(2) dosage group, the highest bone-to-implant contact values were observed. (p<0.05) There were no statistically significant correlations between cortical bone thickness and bone-to-implant contact values; on the other hand, no significant difference was found among the same groups in terms of cortical bone thickness values (p>0.05). CONCLUSIONS: Low-level laser therapy was noticed to induce the mini screw-bone contact area. Low-level laser therapy may be a supplementary treatment method to increase the stability of the orthodontic mini screw.

Distribution of sagittal occlusal relationships in different stages of dentition

The aim of this study was to assess the distribution of sagittal occlusal relationships in different dentition periods in a Turkish sample group. In total, 1,110 patients (561 females, 549 males) aged 4.6-23 years were randomly chosen after intraoral clinical examination. The subjects were classified according to their sagittal occlusal relationships and four dentition stages –deciduous, early mixed, late mixed, and permanent dentition. The statistical significance of the occurrence of malocclusion types in dentition stages was evaluated by Chi-square and Fischer’s exact tests. Class I malocclusion was observed at the highest rate in all dentition stages. Class III malocclusion was observed at the highest rate in the permanent dentition, whereas Class II malocclusion was observed at the highest rate in the late mixed dentition. The rates of Class I, II, and III malocclusions were similar in males and females. Our study reveals that the prevalence of malocclusion and need for orthodontic treatment has increased in the population towards the permanent dentition.

Changes in the soft tissue profile after extraction orthodontic therapy.

PURPOSE: The purpose of this study was to evaluate the effects of extraction therapy and use or nonuse of headgear on the soft tissue profile in subjects with different growth patterns. METHODS: A total of 41 subjects were included in the study. The patients were treated with standard edgewise mechanics and had 4 first premolars extracted. The type of growth pattern was assessed as mesiodivergent or hyperdivergent. The results were analyzed by 2-way analysis of variance. RESULTS: When comparing the mean changes between growth pattern types, the vertical changes in Sn and A' were found to be statistically significant (P<.05). The vertical change in A' was also found to be significant between the headgear use and nonuse groups (P<.05). Interaction was found to be significant for Steiner upper and lower lip values and the vertical change in A. The upper and lower lips were retracted significantly more by headgear use in patients with hyperdivergent growth pattern (P<.05). CONCLUSIONS: The results of this study indicate that the use of headgear should be avoided in hyperdivergent patients. The avoidance of premolar extraction, based on the possibility of a significant detrimental effect on the facial profile, is not justified.