Dental and Alveolar Inclination after Asymmetric Rapid Maxillary Expansion in True Unilateral Posterior Crossbite Cases

Aim:The objective of the present study was to evaluate maxillary dental and dentoalveolar changes in true unilateral posterior crossbite cases treated with asymmetric rapid maxillary expansion.Subjects and Methods:The study group comprised 38 patients in the permanent dentition divided into two groups as treatment (experimental) and control. In treatment group, for asymmetric rapid maxillary expansion, an acrylic bonded appliance was used. Orthodontic study models were obtained before RME (T1), after expansion (T2), and after retention period (T3) in treatment group and at the beginning of control and at the end of control in control group. A line of barium sulphate solution was drawn between the upper first molars on the models, and radiographs were taken. Buccal tipping of the molar crowns and alveolar processes were evaluated on the radiographic images of the models.Results:In the treatment group, there were statistically significant increases both after expansion (11.22°) and retention (9.65°) periods in the alveolar inclination angle (β) (p0,05).Conclusion:The asymmetric rapid maxillary expansion with a bonded RME appliance with full occlusal coverage of all upper teeth was found to be effective in correcting true unilateral posterior crossbites. The tipping of the first molars can be relatively decreased by this appliance

Mechanical Properties of Different Aesthetic Archwires

Objectives:In response to patient demands for better aesthetics in orthodontics, manufacturers have developed different aesthetic wires and brackets. The aim of this study were to evaluate the mechanical properties of archwires. Thus, color properties and surface roughness of the different aesthetic archwires were analyzed.Materials and Method:Seven brands of aesthetic archwires were evaluated for color and roughness measurements. The color measurement of each sample was performed using a spectrophotometer. A profilometer was used to measure surface roughness. For roughness, Ra (average roughness), Rq (root mean square roughness), and Rz (maximum peak to valley height) parameters were used. A Kruskal-Wallis test was used to compare intergroup differences. For pairwise comparisons, a Mann- Whitney U test was used.Results:Intergroup comparisons revealed remarkable differences between groups for all parameters. The surface roughness and Commission Internationale de l’Eclairage L*a*b* color values were statistically different from each other for all intergroup comparisons (p , .001).Conclusion:Having different color options for aesthetic wires gives clinicians an advantage in terms of the ability to choose archwires that are more harmonious with individual teeth in terms of bracket color and thus provide a more aesthetic appearance

Sınıf II subdivizyon maloklüzyonda mandibular asimetrinin değerlendirmesi

Amaç: Bu çalışmanın amacı Sınıf II subdivizyon maloklüzyonlardaki mandibular iskeletsel asimetrilerin prevalansını, Sınıf I ve Sınıf II maloklüzyonlarla karşılaşırmalı olarak belirlemektir.Gereç ve Yöntemler: Çalışmaya her biri 40’ar bireyden oluşan 3 grup dahil edilmiştir: bir Sınıf I oklüzyon grubu (14 erkek ve 26 kadın; yaş ortalaması 14.68±1.86), bir Sınıf II oküzyon grubu (12 erkek, 28 kadın ; yaş ortalaması 14.02±1.74), ve sınıf II subdivizyon oklüzyon grubu (19 erkek and 21 kadın; yaş ortalaması 14.32±2.42). Her bir hasta için panoramik radyogramlarda(OPG) sekiz doğrusal ve bir açısal ölçüm yapılmıştır. Sağ ve sol ya da Sınıf I ve Sınıf II tarafların ölçümlerini kıyaslamak için Wilcoxon testi kullanılmıştır. Grup içi değerlendirmelerde P < 0,05 seviyesindeki asimetrilerin kıyaslanması için Kruskal-Wallis ve post-hoc Mann- Whitney U testleri kullanılmıştır.Bulgular: Sınıf I ve Sınıf II veya subdivizyon grubundaki bireylerin Sınıf I tarafları ve Sınıf II tarafları veya sağ sol tarafları arasında, yalnızca gonial açıda anlamlı farklılık gözlenmiştir (P < 0.05). Sınf II subdivizyon grubundaki kondil boyları ve korpus uzunluklarındaki asimetri indeksleri diğer gruplara kıyasla daha büyüktür (P < 0.05) ve diğer asimetri indeksleri açısından gruplar arasında anlamlı bir farklılık gözlenmemiştir (P < 0.05).Sonuçlar: Sınıf II subdivizyon grubundaki bireyler, Sınıf I ve Sınıf II gruplarındakilere kıyasla daha asimetrik mandibulaya sahiptir

Effects of the Activator and Twin Block on Facial Soft Tissue Thickness in Class II Division 1 Patients

Objective:The purpose of this study was to evaluate and compare the effects of the activator and Twin Block appliances on soft tissue thickness in Class II division 1 patients.Materials and Methods:Soft tissue thickness measurements were obtained from standardized lateral and posteroanterior cephalograms taken at the beginning and end of the time the appliances were used. The study patients consisted of 3 different groups: the control group (group I) comprised 30 patients (13 male, 17 female; mean age: 12.15 6 0.61 years); the activator group (group II) comprised 30 patients (12 male, 18 female; mean age: 12.15 6 0.68 years); and the Twin Block group (group III) comprised 30 patients (14 male, 16 female; mean age: 12.10 6 0.62 years). In the present study, 12 linear anthropologic points were measured. Intragroup comparisons were analyzed using the paired samples t test; and for the intergroup comparisons, the ANOVA and Tukey tests were used at the p , 0.05 level.Results:According to the intragroup comparisons, there were significant differences in groups II and III in the skeletal measurements (SNB, ANB, L1-NB, UL-E plane, and LL-E plane), and in the soft tissue thickness measurements (labrale superius, stomion, labiomental, pogonion, and gnathion) (p,0.05). When the treatment changes were compared between the groups, there were no significant differences between groups II and III. However, between groups I and II or III there were significant differences in the measurements of the SNB, ANB, L1-NB, UL-E plane, LL-E plane, and labiomental soft tissue thicknesses.Conclusions:Both the activator and Twin Block therapies improved the mandibular advancement in Class II patients and affected the soft tissue thickness in a similar way; only the labiomental region was affected

İNSAN MANDİBULASINDA SONLU ELEMANLAR METODU KULLANILARAK GERİLME ANALİZİ YAPILMASI

In this study use of the finite element method in biomechanics, and an explanation of basicsteps of preparing a FEM model of a mandible, a discussion of the validity of results is the objective. Acomputer FEM model of a mandible is prepared from a real human mandible and stress analysis wasconducted. For this purpose CT sections of the mandible of a 22 year old male was obtained and theimages were scanned and transferred to the computer. In the study the steps of preparing a FEM modelof a human skeleton is explained in detail. By using them a 3 D model of the mandible prepared. One ofthe models is prepared with solid elements; the other is prepared with shell elements. The same loadingswere applied to both of them. The results are compared and it is concluded that there is no importantdifferences between them.Bu çalışmada, sonlu elemanlar metodunun biyomekanikte kullanıldığı bir durum için, modelinhazırlanmasının temel aşamaları ve elde edilen sonuçların geçerliliğinin tartışılması amaçlanmıştır. Birinsan mandibulasının sonlu elemanlar programında gerilme analizini yapmak için bilgisayar modelihazırlanmıştır. Bu amaçla 22 yaşındaki bir erkek mandibulasının bilgisayarlı tomografisi (CT) alınmış,elde edilen görüntüler bilgisayar ortamına aktarılmış ve mandibulanın 3 boyutlu sonlu elemanlarmodeli hazırlanmıştır. Çalışmada modelin hazırlanmasında izlenen adımlar detaylı olarak verilmiştir.Sonlu elemanlar metodu (FEM) ile analizde, mandibulanın kabuk ve tuğla-solid elemanlar kullanılarakelde edilen modelleri ile yapılan gerilme karşılaştırması da verilmiştir. Bu modeller değerlendirildiğindesolid ve kabuk elemanlarla yapılan modellerin yaklaşık aynı mekanik davranışı yansıttığı belirlenmiştir.Kabuk elemanlarla hazırlanan modelin kolay elde ediliyor olması nedeniyle daha kullanışlı olduğugörülmüştür

3-Year Follow-Up of Nonextraction Crowded Cases Treated With the Damon System

Objective:The aim of this retrospective study was to investigate treatment efficiency and 3-year follow-up stability of the Damon system by evaluating peer assessment rating (PAR) index, posteroanterior-lateral cephalometric changes, and the intercanine and intermolar widths.Materials and Methods:Fifty-five patients treated with a 0.022-inch slot Damon D3 MX bracket system were evaluated in this study. Cephalometric radiographs, dental models, and PAR scores were measured and evaluated pretreatment (T1), posttreatment (T2), and 3 years after treatment (T3). Repeated-measures analysis of variance (ANOVA)/paired t test were performed to evaluate the differences between the periods.Results:The mean PAR score of 34.75 at T1 was reduced to 3.35 and 3.05 at T2 and T3, respectively, succeeding in a 90.35% reduction with treatment. At T1–T2 and T1–T3, maxillary intercanine and intermolar width and mandibular intercanine width increased significantly. Although intercanine and intermolar widths decreased in both arches at T2–T3, only maxillary intercanine width showed a small, but statistically significant decrease (0.09 mm, p=0.001). Value of SNB angle, Md1-NB (mm), Md1-NB (degrees), and E plane-lower lip increased significantly at T1–T2 and T1–T3. Therefore, treatment resulted in mandibular incisor and lower lip proclination. All of the posteroanterior cephalometric changes were statistically significant except facial width changes at T1–T2.Conclusions:This study represented satisfactory results and a good follow-up stability with the Damon system. The Damon system can be used for nonextraction treatment in patients with moderate crowding

Unilateral Dudak Damak Yarığına Sahip Hastalarda Farengeal Havayolunun Değerlendirilmesi

Amaç: Bu çalışmanın amacı unilateral tam dudak damak yarığına (UDDY) sahip hastaların farengeal hava yolu alanı, yumuşak damak ölçümleri ve kraniyoservikal postürünün değerlendirilmesi ve bu değerlerin dudak damak yarığına sahip olmayan kontrol grubu hastaları ile karşılaştırılmasıdır.Gereç ve Yöntemler: Çalışmaya rastgele ve retrospektif olarak seçilen 60 hasta dahil edilmiştir ve 2 gruba ayrılmıştır. Birinci grup UDDY (30 hasta; ortalama yaş, 15,07 ± 5,61 yıl), ikinci grup ise DDY olmayan iskeletsel Sınıf I (30 hasta; ortalama yaş, 16,34 ± 3,18 yıl) hastalardan oluşmaktadır. Hastalardan alınan lateral sefalometrik filmler üzerinde farengeal hava yolu alanları, yumuşak damak ölçümleri ve kraniyoservikal postür açıları hesaplanmıştır. Elde edilen verilerin gruplar arası karşılaştırmasında bağımsız T-testi kullanılmıştır.Bulgular: UDDY grubundaki hastaların kontrol grubuna kıyasla önemli ölçüde daha küçük toplam ve aerial nazofarengeal alana sahip olduğu bulunmuştur (P <0,05). Ayrıca UDDY grubundaki hastaların yumuşak damaklarının daha kalın ve daha kısa olduğu bulunmuştur (P <0,05). Adenoidal nazofarengeal alan, orofarengeal alan, sert damak/yumuşak damak açısı (ANS-PNS-P°) ve kranioservikal postür açılarında (NSL/CVT° ve NSL-OPT°) iki grup arasında istatistiksel olarak anlamlı bir farklılık bulunmamıştır (P >0,05).Sonuç: UDDY sahip hastaların toplam ve aerial nazofarengeal alanları kontrol grubuna göre daha küçüktür. Bu nedenle bu hastalarda tedavi planlaması yapılırken farengeal hava yolu üzerine pozitif bir etkiye sahip olmasına dikkat edilmelidir. Anahtar Kelimeler: havayolu; sefalometri; yarık dudak; yarık dama

Effects Of Self Etchıng Adhesıve System Whıch Have Antıbacterıal Characterıstıcs On Shear Bond Strengths After Demoralızatıon

Demineralization around the brackets during orthodontic treatment is still a major problem in orthodontics. It has been reported that antibacterial bonding agents that were developed in recent years act as an antibacterial agent against bacteria that was left in the cavity and bacterial invasion resulting from micro leakage. Similarly, with the prevention of bacterial growth around orthodontic brackets caries formation could be prevented. For this reason the effects of an antibacterial bonding agent on artificial demineralization around brackets were investigated by means of bond strength evaluation. The material of this study consisted of 60 freshly extracted human premolar teeth that had no cracks or fractures. Brackets were bonded to buccal surfaces of teeth using Clearfill ABF bond that consisted of MDPB and Clearfill SE Bond and Transbond Plus bonding agents that does not contain MDPB but has the same chemical composition as Clearfill ABF Bond. All the teeth were left in experimental decalcification solution for 14 days. At the end of this period, all the brackets were tested in a universal test machine. The obtained data were analyzed using ANOVA, Tukey HSD test and chi-square analysis. The results of ANOVA showed statistically significant differences (p<0,05). Mean bond strengths were found to be clinically acceptable when compared with the results of other studies. However, the results of our study showed that brackets bonded using Clearfill ABF Bond projects significantly lower bond strengths. The 3 different adhesive systems used in this study effects the failure characteristics of brackets in an important degree

Effect of Orthodontic Bracket Base Structure on Shear Bond Strength

Direct bonding is the method of choice for attaching fixed orthodontic appliances. These fixed appliances are produced with various bonding bases. The present study aims to compare shear bond strengths (SBS) and fracture characteristics of the bracket adhesive interface of six different bracket base types. Standard mesh base (Ultraminitrim-Dentaurum, Germany), Supermesh base (Microarch- GAC, USA ), Integral base (Dyna-Lock, 3M Unitek, USA and Micro -loc GAC, USA), Micro-etched base (Mi -niature Twin, 3M-Unitek), and laser structured base (Discovery-Dentaurum, Germany) brackets were used. Twenty brackets of each type were bonded to specially constructed 120 bonding bases with Transbond XT (3M Unitek, USA). A testing machine (Model 500, Testometric, Lancashire, England) was used to evaluate shear bond strengths for all groups. After debonding, the amount of residual adhesive on the bracket was assessed according to the adhesive remnant index (ARI). ANOVA revealed statistically significant differences among the 6 groups tested (P<0.05). According to the results of Duncan's test highest SBS was achieved by laser treated Discovery brackets. This was followed by Micro-loc and Miniature Twin brackets. The SBS achieved by the latter two were lower but the difference with laser structured Discovery was statistically insignificant. The lowest SBS was achieved by Microarch bracket. From the results obtained in our study, we suggest that differences in bracket base design may lead to significant differences in shear bond strengths. Micro-loc, Miniature Twin or Discovery bases may be preferred to achieve higher shear bond strengths values and to reveal more accurate resin-enamel bond strength values in bond strength studies

Investıgatıon Of The Influence Of Compensatıon Treatments On Soft Tıssues In Class Iı Dıvısıon 1 Mandıbular Retrognathıe Cases

The aims of this study were, 1. To determine the changes in soft tissues with Holdaway soft tissue analysis of Class II Division 1 mandibular retrognathie patients treated with upper two first premolars extraction, 2. To investigate the sexual differences between pre- and post-treatment values of boy and girl subjects, 3. To compare these values with the Holdaway soft tissue Turkish norms. The study group comprised the lateral cephalo-grams of 14 boys (mean age: 16.07+1.08 years) and 14 girls (mean age: 17.05+1.05 years) totally 28 (mean age: 17.00±1.06 years), skeletal Class II, dental Class II division 1 patients. Ten linear and 2 angular measurements were analyzed according to the definition provided by Holdaway on pre and post treatment radiographs. For statistical evaluation paired samples t-test and student t-test were performed. Soft tissue subnasale to H line, H angle, upper lip sulcus depth, skeletal profile convexity and upper lip strain measurements decreased and nose prominence, upper lip thickness and soft tissue chin thickness measurements increased during treatment period. Statistically significant sex differences were only found in nose prominence and H angle measurements between pre- and post-treatment values. In the comparison of these values with Holdaway soft tissue Turkish norms, soft tissue facial angle, nose prominence, soft tissue subnasale to H line, basic upper lip thickness, upper lip thickness and H angle measurements become closer to the Turkish norms. All changes were desirable for improvement of patients' soft tissue profile with extraction of upper two first premolars. The results of this study indicated that, generalizations concerning the negative effects of extraction compensations treatments on the profile of Class II Division 1 mandibular ret-rognathie patients are not true. It is necessary to investigate this difference in further investigations, using the parameters for soft-tissue analysis, need to be repeated with a larger sample