Influence of structural properties of orthodontic wires on biocompatibility and pain perception at the beginning of treatment with fixed orthodontic appliances

Ciljevi studije su bili: utvrđivanje i poređenje percepcije bola kod pacijenata na početku terapije fiksnim ortodontskim aparatima nakon ligiranja nikl titanijumskih (NiTi) žica šest različitih proizvođača; ispitivanje morfologije i mogućih promena sadržaja Ni i Ti u površinskom sloju legure, kao i otkrivanje moguće veze između percepcije bola i strukture ortodontskih žica. Grupa ispitanika se sastojala od 189 osoba (84 muškarca i 105 žena). Svakom pacijentu je ligirana jedna od šest nitinolskih žica različitih proizvođača, prečnika 0.014" raspoređenih metodom slučajnog izbora, koja je u ustima bila mesec dana. Pacijanti su dobili da popune modifikovani McGill upitnik za bol sa VAS-om koji je zatim analiziran, a rezultati su statistički obrađeni. Nove i korišćene žice nakon mesec dana su podvrgnute SEM i EDS mikroanalizi radi utvrđivanja sadržaja Ni i Ti, kao i morfoloških karakteristika površine legure. Nije pronađena statistički značajna razlika u percepciji bola između grupa ispitanika sa različitim žicama. Bol se najčešće javljao nakon 6 sati, kao pritisak u zubima provociran žvakanjem, trajao je 2 dana i prestajao bez upotrebe analgetika. Uočena je promene u sadržaju Ni i Ti između novih i korišćenih žica, kao i drugačija površinska morfologija. Površinska struktura ortodontske žice, nakon izlaganja uslovima usne duplje, podleže promenama u sadržaju Ni i Ti koje nisu povezane sa percepcijom bola kod ispitanika.The aims of this study were: to investigate and compare pain perception of patients at the beginning of orthodontic treatment with fixed appliances after insertion of six different archwires; to examine alterations in Nickel (Ni) and Titanium (Ti) surface composition and morphology in as received and retrieved archwires; to establish any possible connection between pain perception and structure of the nickel titanium (NiTi )alloy. The study group consisted of 189 orthodontic patients, 84 males and 105 females. Following insertion of 0.014" NiTi archwires from six different manufacturers, which was performed by random selection, a modified McGill pain questionnaire with VAS, comprising of questions regarding intensity, provocation, beginning, duration, quality of pain and analgesic consumption was given to each patient. As-received and retrieved archwires (after one month) were subjected to SEM and EDS micro analyses. No significant differences were found between groups of patients with different archwires in terms of perception of pain. In all groups of patients, pain was provoked by chewing, perceived as a pressure starting after 6 hours, lasted 2 days and decreased without pain medication. SEM and EDS showed changes in Ni and Ti content in as-received and retrieved archwires with visible alterations of alloy surface topography. Intraoral exposure of different NiTi archwires alters the content of Ni and Ti in surface layers as well as their morphology, but the relation to pain perception was not found

Correlation of dental and chronological maturity in girls and boys aged 7 to 14 years

The aim of the study was to assess correlation level of dental and chronological maturity related to gender in a group of children of our population. Material and method: Total number of 320 girls and boys, 7 to 14 years old, participated in the study. Dental age assessed by Demirjian's method. Statistical data were analyzed by mean value and SD for dental maturity in age groups of 7, 8, 9, 10, 11, 12, 13 and 14 years for girls and boys, respectively. Calculating the equation of linear regression and the determination and correlation ratio assessed correlation level of dental and chronological age. Results and conclusion: According to the results obtained, it can be concluded that mean values of dental age are coinciding with the chronological maturity in all 8 age groups which is confirmed by high interdependence of dental and chronological maturity (78.6% for boys and 79.6% for girls).

Bond strength of orthodontic adhesives

The objective of this study was to evaluate and compare bond strength of four adhesives used in orthodontics for bonding brackets to tooth enamel. The adhesives used in this investigation were resin-reinforced glass-ionomer cement (Fuji Ortho LC-GC Corporation, Japan), light cured composite resin adhesives (ConTec LC-Dentaurum, Germany and Enlight Bonding system-Ormco, USA) and dual cured composite resin adhesive (ConTec Duo-Dent aurum, Germany). A sample of 80 extracted human premolars was divided into four groups of 20 teeth which were etched with 37% phosphoric acid and bonded in dry field to enamel of buccal and lingual surfaces of the teeth with the same adhesive in one group. The debonding force was produced using universal Instron testing machine with cross head speed of 1mm/min and shear bond strength was measured. Statistical analysis used in this study included: Kolmogorov-Smirnov test i Shapiro-Wilk test, Mann Whitney test, Kruskal Wallis chi-squared test. Even though, all four adhesives showed sufficient bond strength for orthodontic bonding, ConTec LC and ConTec Duo displayed the superior bonding properties comparing to Enlight and Fuji Ortho LC.

Dojenje iz ugla dečjeg stomatologa

Current recommendations by the European Academy of Paediatric Dentistry, American Academy of Paediatric Dentistry, and International Association of Paediatric Dentistry advocate weaning from breast milk and avoiding unrestricted breastfeeding after the eruption of primary teeth in order to lower the risk of early childhood caries (ECC). However, World Health Organization, American Academy of Paediatrics and nutritional recommendations support exclusive breastfeeding up to six months of age, following continued breastfeeding along with appropriate complementary foods, favouring unrestricted and prolonged breastfeeding even beyond the age of two. The purpose of this review is to discuss current data in the literature regarding the association between breastfeeding and ECC in order to address this problem and to provide consistent recommendations. PubMed search revealed possible link between breastfeeding and ECC, however without evidence strong enough to establish the appropriate oral health preventive recommendation. Having in mind known benefits of breastfeeding, it is advisable to adhere to current paediatric guidelines which promote unrestricted breastfeeding as long as it is mutually desired by mother and child. This recommendation doesn't exclude but complements the prevention and timely treatment of ECC. Furthermore, there is a need to highlight the importance of education of parents and health care providers about the ECC risk factors, identification of initial lesions and consequences. Further research regarding this issue is needed.Savremene preporuke Evropske i Američke akademije dečjih stomatologa i Međunarodnog udruženja dečjih stomatologa savetuju postepeni prekid dojenja nakon nicanja mlečnih zuba kako bi se smanjio rizik od nastanka karijesa ranog detinjstva (KRD). Sa druge strane, preporuke Svetske zdravstvene organizacije, preporuke Američke akademije pedijatara i stručnjaka iz oblasti ishrane prepoznaju brojne kratkoročne i dugoročne pozitivne efekte dojenja i podržavaju isključivo dojenje do uzrasta od šest meseci, a zatim postepeno uvođenje čvrste hrane sa nastavkom dojenja uz neograničeno i dojenje na zahtev do druge godine deteta i duže. Cilj ovog preglednog rada je bio da se analiziraju savremeni podaci u literaturi o uticaju dojenja na nastanak KRD, kako bi se doprinelo formiranju jedinstvenog stava i pružila jasna informacija majkama kako prevenirati KRD. Na osnovu pretraživanja Pub Med baze podataka, uočava se da postoji povezanost između dojenja i KRD, ali nije dovoljno argumentovano koje su najbolje mere u prevenciji karijesa. Imajući u vidu poznate pozitivne efekte dojenja, smatra se da je preporučljivo pratiti savremene pedijatrijske preporuke koje savetuju neograničeno dojenje koliko God to uzajamno prija majci i detetu. Ipak, potrebno je imati u vidu neophodnost ranih preventivnih poseta dečjem stomatologu i edukacije zdravstvenih radnika radi adekvatnih i blagovremenih saveta o higijeni usne u duplje i ishrani kako bi se izbegao nastanak karijesa ranog detinjstva i omogućilo blagovremeno dijagnostikovnje inicijalnih lezija. Neophodna su dalja istraživanja u ovoj oblasti

Challenges in experimental evaluation of morphological, chemo-mechanical and adhesive properties of glass-ionomer based dental materials

Changes in composition and new material characteristics require verification in clinical and experimental studies. Investigating glass-ionomer cements under laboratory conditions encounters problems in interpreting the results and in comparing them with other types of materials tested in the same way. As the connection between the glass-ionomer cements and the dental tissues is delicate, it is often the case that the impact of fractures and other artifacts is either underestimated or over-dimensioned when interpreting the results. A critical review was performed, with defining the main problems regarding the usage of SEM, EDX and nanoindentation techniques in glass-ionomer based materials evaluation

Orthodontic treatment of nongrowing patient with class II division 2 malocclusion by Herbst appliance

Background. Inheritance is most casual etiological factor of Class II division 2 malocclusion. This kind of malocclusion is very difficult for treatment specially in older patients. Case report. In the female patient, 20 years old, at the beginning of the treatment at the School of Dentistry in Belgrade, lateral cephalogram showed skeletal and dentoalveolar Class II division 2 malocclusion. She was in the Herbst treatment for 8 months and 12 months more with a fixed multibracket appliance. The measurements were performed on lateral cephalograms before and after the treatment: ii, is, mi, ms, Pg and ss. The distance from these points to occlusal perpendicular line (Olp) were measured and compared from cephalogram before to cephalogram after the treatment. Temporomandibular joint (TMJ) tomograms were compared from before and after the treatment by superimposition. Correction was found in molar and incisor relation, overjet and overbite. There were found sagital skeletal changes and soft tissue profile improvement. Conclusion. Herbst appliance is effective in the treatment of Class II malocclusions, even in adult patients. Dental and skeletal changes as a result of Herbst treatment could be good choice instead of camouflage orthodontics or surgical decision

Gold in the past, today and future

This paper deals with gold, which is described as a chemical element. Special attention is paid to its physical-chemical properties and, furthermore, where or in what form it can be found in nature. We discuss the role it has played through history and we inform how gold has been developed to the level it has reached today's value. Still more, when gold is broken into nanoparticles, this form could be highly useful for a wide range of processes, including general nanotechnology, electronics manufacturing and the synthesizing of different functional materials. It is important that we know that gold is also used in industry in many engineering applications (contacts in micro-electronics) and medicine (dental alloys, implants)

Zastupljenost razvojnih anomalija zuba kod ortodontskih pacijenata u Srbiji

Introduction/Objective the aim of this study was to evaluate the prevalence of developmental dental anomalies (DDA) in Serbian orthodontic patients. Methods the sample was composed of 1,001 panoramic radiographs of orthodontic patients, older than seven years, taken as a part of the initial diagnostic procedure at the Clinic of Orthodontics, School of Dental medicine in Belgrade. The DDA that could be diagnosed accurately on panoramic X-rays were documented. Descriptive analysis was used to determine prevalence and sex distribution of DDA. The Pearson ch2 test and Fisher's exact test were used to compare number of affected teeth in males and females (level of significance was 95%). Results the prevalence of DDA in Serbian orthodontic patients was 34.8% (15.5% males and 19.3% females). Impactions were present in 16.5%, hypodontia in 12.9%, hyperdontia in 4.4%, microdontia in 2.9%, macrodontia in 1.8% and transposition in 0.8% of patients. Maxillary canines were the most frequently impacted teeth. Maxillary second molars were more prone to impaction in females (p lt 0.05). Impacted incisors were more prevalent in maxilla, premolars, and second molars in mandible. The most commonly missing teeth were upper left second premolars. Mesiodens was the most frequently found supernumerary tooth. Conclusion We reported a high a rate of DDA in Serbian orthodontic patients, more in females than males. The most frequently observed DDA were impaction, tooth agenesis, hyperdontia, microdontia, macrodontia, and transposition. All investigated DDA were more frequently present in females, except hyperdontia. Current findings could offer a foundation for epidemiological studies on DDA prevalence.Uvod/Cilj Cilj ovog istraživanja je bio da se ispita zastupljenost razvojnih anomalija zuba kod ortodontskih pacijenata u Srbiji. Metode Uzorak je činio 1001 ortopantomografski snimak ortodontskih pacijenata starijih od sedam godina sa Klinike za ortopediju vilica Stomatološkog fakulteta u Beogradu. Beleženo je prisustvo razvojnih anomalija za čiju dijagnostiku je potreban samo ortopantomografski snimak. Za ispitivanje zastupljenosti razvojnih anomalija zuba korišćena je deskriptivna statistička analiza. ch2 test je korišćen radi poređenja broja zuba sa anomalijom između polova (stepen značajnosti 95%). Rezultati Razvojne anomalije zuba su bile zastupljene kod 34,8% ortodontskih pacijenata (15,5% muškaraca i 19,3% žena). Impakcije zuba su bile prisutne kod 16,5% pacijenata, hipodoncija kod 12,9%, prekobrojni zubi kod 4,4%, mikrodoncija kod 2,9%, makrodoncija kod 1,8% i transpozicija kod 0,8% pacijenata. Očnjaci u gornjoj vilici su bili najčešće impaktirani zubi. Gornji drugi kutnjaci su bili skloniji impakciji kod žena (p lt 0,05). Dokumentovano je više impaktiranih sekutića u gornjoj vilici, a pretkutnjaka i drugih kutnjaka u donjoj vilici. Najčešće su nedostajali gornji levi pretkutnjaci. Od svih prekobrojnih zuba najčešće je bio uočavan meziodens. Zaključak Prikazali smo postojanje visoke učestalosti razvojnih anomalija zuba kod ortodontskih pacijenata u Srbiji sa većom izraženošću kod osoba ženskog pola. Najčešće anomalije bile su impakcija, hipodoncija, hiperdoncija, mikrodoncija, makrodoncija i transpozicija. Sve anomalije su bile učestalije kod žena, osim u slučaju prekobrojnih zuba. Rezultati sadašnje studije mogu biti polazna tačka za epidemiološke studije o učestalosti razvojnih anomalija zuba

Analysis of the pattern, type and the extent of dental services provided to children and youth on the territory of Republic of Serbia

Background/Aim: The requirements for dental specialties and the number of specialists in each country are unique and strong indicator of the availability and affordability of primary health care for children and adolescents. The aim of this study was to determine the pattern, type and the extent of dental services, as well as the influence of regional factors and data on whether services are provided by a pediatric dentist or general dentist have effect on these parameters, based on information obtained from dentists providing dental care to children and youth. Material and Methods: Within the project "Program for the improvement of oral health of children and youth in the Republic of Serbia", supported by the Ministry of Health of Serbia, a research was conducted among dentists involved in dental care for children and youth in Serbia. Data collection from primary health care facilities was performed through a specially designed questionnaire. A total of 445 questionnaires were collected from dentists from 102 health centers in Serbia in the period June - October 2019. Results: There are significant differences between regions in the pattern, type and the extent of dental services. In the quantitative analysis, there are no significant differences in the type of dental services between pediatric and preventive dentistry specialists and general dentists. Conclusions: The data from the conducted research speak in favor of a large daily workload of dentists who deliver oral health care for children and youth in Serbia. Additional multifactorial analysis, which includes epidemiological data from the region, but also environmental, demographic and cultural parameters of oral health could be the basis for improving the provision of preventive dental and preventive oral car

Dentoalveolarni terapijski efekti Herbst aparata i aktivatora kod osoba u postpubertetskom uzrastu sa malokluzijom klase II/1

Background/Aim. Functional appliances can be used effectively in the treatment of skeletal Class II/1 malocclusions. The best treatment results are obtained during active period of facial growth when skeletal, as well as dentoalveolar, changes occur. In comparison with removable functional appliances, such as activator, that are effective only during adolescent period of growth, the Herbst fixed appliance is also successful at the end of the growth period. It also offers a shorter treatment time and a patient compliance is not necessary. The aim of this study was to analyze and compare dentoalveolar changes in the group of young adult patients with Class II/1 malocclusion treated with the Herbst appliance and an activator. Methods. The sample for this study consisted of 50 patients of both sexes, 14-21 years of age with Class II/1 malocclusion. For estimating the effect of functional appliances used, the following cephalometrics parameters were determined: inclination of the upper and lower incisors, interincisal angle, antero-posterior molars relationships, overjet and overbite. The results obtained were statistically tested. Results. The cephalometric findings after the treatment indicated retroinclination of upper incisors (average value of 9°) and proclination of lower incisors (average value of 7°), mostly expressed in the patients treated by Herbst appliance (p lt 0.001). Increased overjet and distocclusion were completely corrected in the group of patients treated with the Herbst appliance, while the correction of malocclusion in the activator group was only partially accomplished. No changes in the overbite were noticed at the end of the treatment in both groups. Conclusion. The results of this study revealed that the Herbst appliance is more effective in the treatment of Class II/1 malocclusion in young adults in comparison with the activator.Uvod/Cilj. Funkcionalni aparati uspešno se koriste u terapiji malokluzija klase II/1. Najbolji rezultati postižu se terapijom u periodu pubertetskog skoka rasta, kada su moguća najveća skeletna i dentoalveolarna pomeranja. U poređenju sa terapijom pokretnim funkcionalnim aparatima, kao što je aktivator prema Andresen-u, terapija Herbst-ovim fiksnim aparatom (Herbst aparat), uspešna je i nakon pubertetskog skoka rasta, vreme terapije je kraće, a bolesnike ne treba motivisati za saradnju jer je aparat fiksiran na zubima. Cilj istraživnja bio je da se kod bolesnika mlađeg odraslog uzrasta sa malokluzijom klase II odeljenja 1 uporede efekti fiksnog funkcionalnog Herbst aparata i pokretnog aktivatora na dentoalveolarne strukture. Metode. Ispitivanje je obuhvatilo 50 bolesnika sa malokluzijom klase II/1, oba pola, uzrasta 14-21 godine. Efekti primenjenih funkcionalnih aparata, aktivatora prema Andresen-u i Herbst aparata, procenjivani su na osnovu parametara merenih na profilnim telerendgenskim snimcima, nagiba gornjih i donjih sekutića, interincizalnog ugla, okluzije po Angle-u, incizalnog stepenika i incizalnog preklopa. Dobijeni rezultati obrađeni su statistički. Rezultati. Tokom terapije nastupile su statistički visokoznačajne promene u obe grupe: oralno naginjanje gornjih i vestibularno naginjanje donjih sekutića. Promene su bile izraženije u grupi bolesnika lečenih Herbst aparatom (p lt 0,001). Nagib gornjih sekutića promenjen je prosečno oko 9°, a donjih oko 7°. Odnos molara i incizalni razmak su u potpunosti korigovani na kraju lečenja u grupi lečenoj Herbst aparatom, dok su isti parametri u grupi sa aktivatorom bili nepotpuno korigovani. Nijedan od primenjenih aparata, na završetku lečenja, nije izazvao promene u vertikalnom preklopu sekutića. Zaključak. Poređenje terapijskih efekata Herbst aparata i aktivatora kod bolesnika uzrasta 14-21 godinu pokazalo je da je Herbst aparat efikasniji u korekciji dentoalveolarne malokluzije klase II odeljenja 1 nego aktivator