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    Biocomposite materials in orthodontics
    (Nova Science Publishers, Inc., 2023) Cicek, Orhan; Ozkalayci, Nurhat; Yetmez, Mehmet
    Biomaterials are called non-vital materials intended to interact with biological habitats. Any material that emerges as a bioengineering product can be considered as a biomaterial in the repair and reconstruction of lost, debilitated, or infarcted tissues. They differ from other materials in that they have chemical, mechanical, physical, and biological properties that make them suitable for use in a physiological medium. In this context, these biomaterials are applied in a wide range of fields such as medicine, dentistry, veterinary and pharmacology, which are in close and continuous contact with body tissues. The most fundamental feature that should be in a biomaterial planned to be used in medical applications is biocompatibility and it is seen that single-phase homogeneous, isotropic and so called isotropic materials such as metal, polymer and ceramic are used. Mechanical weakness, liquid absorption, and leaking in polymers, a tendency to create image artifacts in threedimensional imaging methods in metals, and low mechanical reliability, brittleness, fabrication difficulties, and lack of elasticity in ceramics are main points of all disadvantages for these materials. These disadvantages have led to the development of composite biomaterials, which exhibit multi-phase material properties without losing their properties, which are consist of two or more materials with different chemical structures. Composites, which were called biocomposites for the first time in 1991 with their use in the human body, are a mixture made by maintaining the superior properties of two different materials and losing their inferior properties. For the sake of biocompatibility, there are natural biocomposites such as bones, teeth, skin, cartilage, tendons and ligaments, as well as resin-based composite filling materials in dental applications. Biocompatible and biodegradable biocomposites with superior mechanical properties for use in oral and dental tissue engineering have been developed mainly by using multiple biocompatible material mixtures. Consequently, in the design of biocomposite materials used in humans, the suitable selection of matrix and materials, appropriate production and processing methods, and the internal-external design of the device must be taken into account correctly. In this chapter, not only biocomposite materials used in orthodontic practices are discussed but also dental implant and prosthetic bridge applications. In fixed orthodontic treatment, orthodontic brackets and arch wires placed in the slots of these brackets are used for the leveling and proper alignment of the teeth. In general, both brackets and arch wires are manufactured from metal alloys. Composite arch wires, however, offer the benefits of aesthetics, ease of forming, and the ability to alter stiffness without changing component dimensions. Again, polymer composite orthodontic brackets need to be developed due to disadvantages such as the abrasion of tooth enamel of ceramic orthodontic brackets and the unaesthetic appearance of metallic brackets and the risk of allergic reaction. The aim of this chapter is (i) to reveal the current findings on biocomposite materials used in the field of orthodontics and (ii) to discuss new and futher results for behaviors of biocomposite materials under various orthodontic force conditions. © 2024 by Nova Science Publishers, Inc. All rights reserved.
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    Effect of Different Types of Adhesive Agents on Orthodontic Bracket Shear Bond Strength: A Cyclic Loading Study
    (Mdpi, 2023) Eser, Irfan; Cicek, Orhan; Ozkalayci, Nurhat; Yetmez, Mehmet; Erener, Hande
    Bracket failure is one of the most important problems encountered during fixed orthodontic treatment. For this reason, different types of adhesive agents have been developed over the years. Consequently, the aim of this study was to evaluate the shear bond strength of brackets bonded to teeth etched with a conventional acid etching method in a laboratory environment by using different types of adhesive agents and comparing the number of shear strokes. Sixty human maxillary premolars were divided into three groups and Gemini stainless steel metal brackets (3M Unitek, Monrovia, CA, USA) were bonded to all teeth. In Group 1, Transbond (TM) XT Primer (3M Unitek, Monrovia, CA, USA) and Transbond (TM) XT Light Cure Adhesive Paste composite (3M Unitek, Monrovia, CA, USA) were used. In Group 2, BracePaste((R)) MTP Primer (American Orthodontics, Sheboygan, CA, USA) and BracePaste((R)) Adhesive composite (American Orthodontics, Sheboygan, WI, USA) were used. In Group 3, Ortho Solo (TM) Primer (Ormco, Orange, CA, USA) and Grengloo (TM) Adhesive composite (Ormco, Brea, CA, USA) were used. The samples were subjected to a shear test with a closed-loop controlled, low-cycle fatigue machine with a capacity of 10 N and a crosshead speed of 300 mm/min. The number of shear strokes of the brackets was recorded. According to the Kruskal-Wallis and Mann-Whitney U tests performed on the data obtained, statistically significant differences were found between the groups in terms of the numbers of shear strokes (p < 0.05). Significantly higher numbers of shear strokes and higher shear bond strengths were observed in Group 3 compared with Group 1 and Group 2 (p < 0.05). There was no statistically significant difference between the numbers of shear strokes for Group 1 and Group 2 samples (p > 0.05). To conclude the study, it was observed that the type of adhesive used had an effect on the bond strength of the bracket and that the Grengloo (TM) adhesive agent showed higher shear bond strength. It was observed that BracePaste((R)) Adhesive and Transbond (TM) XT Light Cure Adhesive Paste adhesive agents had similar shear bond strengths.
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    Evaluation of the Demineralization Development around Different Types of Orthodontic Brackets
    (Mdpi, 2023) Ertop, Melis Toz; Cicek, Orhan; Erener, Hande; Ozkalayci, Nurhat; Cicek, Busra Demir; Comert, Fusun
    The aim of this study was to compare the demineralizations of the enamel surfaces around different types of orthodontic brackets in an artificial cariogenic environment. A total of 90 extracted human maxillary first premolar teeth were used in this in vitro study. The teeth were divided into 6 groups, 5 study and 1 control, each consisting of 15 samples. Victory metal, Gemini metal, Clarity self-ligating ceramic, APC Clarity Advanced ceramic and Clarity Advanced ceramic brackets (3M Unitek, Monrovia, Calif) used in the study groups were bonded to the teeth with the direct technique. The gingival, occlusal and proximal enamel surfaces adjacent to the brackets were measured with a DIAGNOdent pen (KaVo, Biberach, Germany) (T0). Then, the teeth were placed in a cariogenic suspension environment containing Streptococcus mutans, sucrose and artificial saliva. The teeth were removed from the cariogenic suspension at the end of 28 days. Enamel surfaces were remeasured with DIAGNOdent and the values were recorded (T1). Whether the obtained data were homogeneously distributed or not was determined by the Kolmogorov-Smirnov test, within-group comparisons were performed with the Wilcoxon test, and between-group comparisons were performed with Mann-Whitney U and Kruskal-Wallis tests. Significance level was accepted as p < 0.05. In all groups, the demineralization values of the enamel surfaces in the gingival, proximal and occlusal surfaces adjacent to the brackets were significantly higher in the T1 period than in the T0 period (p < 0.05). In the T1 period of Gemini metal, Clarity self-ligating ceramic and Clarity advanced ceramic bracket groups, the demineralization values of the proximal enamel surfaces were found to be significantly higher than the Victory metal and APC Clarity Advanced ceramic bracket groups (p < 0.05). In the T1 period, the demineralization values of the occlusal enamel surfaces of the Victory metal, APC Clarity Advanced ceramic bracket groups and control group were significantly lower than the Gemini metal, Clarity self-ligating ceramic and Clarity Advanced ceramic bracket groups (p < 0.05). Significant increases in enamel demineralization values were observed as a consequence of increased retention areas for microbial dental plaque on enamel surfaces adjacent to the bracket. Considering the importance of minimizing enamel demineralization in fixed orthodontic treatments, less enamel demineralization in Victory metal and APC Clarity Advanced ceramic bracket groups showed that these brackets can be preferred in patients with poor oral hygiene.
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    FONKSİYONEL TEDAVİSİ TAMAMLANMIŞ İSKELETSEL SINIF 2 HASTALARIN SAGİTTAL HAVAYOLUNUN RETROSPEKTİF SEFALOMETRİK BÜYÜME DEĞİŞİKLİKLERİNİN İNCELENMESİ
    (2023) Ay, İbrahim Berat; Çiçek, Orhan; Ozkalayci, Nurhat
    Bu çalışmanın amacı, fonksiyonel tedavi sonrası sagittal havayolu boyutlarında meydana gelen değişikliklerin karşılaştırılmasıdır. Çalışmaya; 47 erkek ve 54 kız toplam 101 hasta dahil edildi. Gruplar; cinsiyet ve aparey tipine göre oluşturuldu.65 adet hareketli (monoblok) ve 36 adet sabit (ForsusTM) aparey kullanılmış hastalarda Sella-Nasion-A açısı (SNA), Sella-Nasion-B açısı (SNB), ve A-Nasion-B açısı (ANB)ve havayolu boyutlarında; alt havayolu boyutu (PNS-AD1), üst havayolu boyutu(PNS-AD2), alt adenoid doku boyutu (AD1-BA), üst adenoid doku boyutu (AD2-HO), üst faringeal boşluk (SPS), orta faringeal boşluk (MPS) ve alt faringeal boşluk (IPS) ölçülerek kaydedildi. Erkeklerde, faringeal boşlukların tümünde anlamlı artma gözlendi (p<0.05). Kızlarda ve hareketli aparey grubunda, üst ve alt faringeal boşluklarda anlamlı artma görülürken, sabit aparey grubunda sadece alt faringeal boşlukta anlamlı artma gözlendi (p<0.05). Tüm gruplarda, anlamlı şekilde SNA ve ANB açılarında azalma ve SNB açılarında artma gözlendi (p<0.05). SNB’de artma ve ANB’de azalma miktarı hareketli aparey grubunda sabit aparey grubuna göre anlamlı şekilde daha fazla bulundu (p<0.05). İskeletsel sınıf 2 maloklüzyonların fonksiyonel tedavisiyle, hem sagittal havayolu boyutlarında anlamlı artışlar sağlanırken hem de normal büyüme ve gelişmenin yönlendirildiği görüldü.
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    Investigation of the Relationship between Sagittal Skeletal Nasal Profile Morphology and Malocclusions: A Lateral Cephalometric Film Study
    (Mdpi, 2023) Ocak, Yunus; Cicek, Orhan; Ozkalayci, Nurhat; Erener, Hande
    The aim of this study was to evaluate the relationship between skeletal sagittal nasal profile morphology and sagittal skeletal malocclusions. Regarding lateral cephalometric films, the study was conducted in a total of 135 individuals without any prior orthodontic treatment (mean age of 17.91 +/- 1.91), including 49 males (mean age 17.91 +/- 1.16) and 86 females (mean age 17.78 +/- 1.91 years). The groups were divided into two groups as male and female according to gender, and three groups as skeletal Class 1, Class 2, and Class 3 according to the Steiner's ANB angle. In addition, skeletal groups were compared within groups by dividing into two groups of male and female. A total of eight parameters, three skeletal sagittal angular (SNA, SNB, and ANB angles), four nasal linear (R-A, N-A, N-ANS, and N-R distances) and one nasal angular (N1-N2/N2-R angle), were measured on each cephalometric film. The arithmetic mean and standard deviation of all measured nasal parameters were calculated. For statistical analysis, independent sample t-test and one-way analysis of variance (One-Way ANOVA) were used for normally distributed data, and Mann Whitney U and Kruskal Wallis tests were used for data that did not show normal distribution. For statistical analysis, p < 0.05 was considered significant. R-A, N-A, and N-ANS linear nasal parameters differed significantly between the male and female groups, which were evaluated regardless of the skeletal groups, with a higher rate in males (p < 0.05). N-R linear nasal parameter showed a statistically significant difference between skeletal malocclusion groups, which were evaluated regardless of gender. N-R distance was found to be significantly longer in skeletal Class 3 individuals than in Class 1 and 2 individuals (p < 0.05). There was no statistically significant difference in nasal bone concavity angle in all groups (p > 0.05). R-A and N-A linear nasal parameters showed statistically significant differences between male and female sex groups in all skeletal malocclusion classes (p < 0.05). At first, results showed that males had longer measurements than females in all linear nasal parameters. Second, longer measurements were found in all linear nasal parameters in skeletal Class 3 individuals than those in skeletal Class 1 and Class 2 individuals. Third, the nasal bone concavity angle was greater in skeletal Class 2 individuals than the others.
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    The Effects of Different Types of Surface Conditioning Methods on Enamel Demineralization: An In-vitro Rebonded Bracket Study
    (2023) Acır, Kemal Can; Çiçek, Orhan; Ozkalayci, Nurhat
    Aim: This study aimed to evaluate the effects of the conventional etching and primer (CEP) method and the self-etching primer (SEP) method on demineralization while rebonding the brackets. Material and Methods: Sixty extracted maxillary first premolar teeth were divided into 4 groups, each containing 15 teeth. The teeth in Groups 1 and 2 were bonded using CEP, and those in Groups 3 and 4 were bonded using SEP. After the first bonding, adjacent surfaces of the brackets were measured using DIAGNOdent pen, and demineralization values were recorded (T0). The teeth were kept in a demineralization solution for 15 days in a 37°C incubator. Then, all brackets were debonded. The teeth in Groups 1 and 3 were rebonded using CEP, and those in Groups 2 and 4 were rebonded using SEP. In this way, via the enamel surface conditioning prior the first bonding and rebonding, the groups were constructed as; Group 1 (CEP-CEP), Group 2 (CEP-SEP), Group 3 (SEP-CEP) and Group 4 (SEP-SEP). The teeth were kept in the same solutions by same way (T1). The Kolmogorov-Smirnov test was used to determine whether or not the data were normally distributed, the Wilcoxon test was used for comparisons within groups, and the Mann-Whitney U and Kruskal-Wallis tests were used for comparisons between groups. p<0.05 was considered significant. Results: At T1, the demineralization values in Group 1 obtained from all surfaces were found to be significantly higher than those in Groups 3 and 4 (p<0.05). The amount of increase in demineralization between T0 and T1 was observed to be the greatest on the gingival surfaces and the smallest on occlusal surfaces in all groups. Regardless of the enamel surface measured, the mean increase in values on all surfaces was the highest in Group 1 and the lowest in Group 4. Conclusion: Considering the effects of orthodontic bracket rebonding on the enamel surface, the self- etching primer method produces less enamel demineralization than the conventional etching and primer method.