Mesiodens and paramolar in the medieval age skeletal remains

Evolution as in all segments of human behavior and existence has left traces on human teeth. The aim of this study was to determine the frequency of the supernumerary teeth in skeletal remains found at the archeological site Stara Torina and SEM evaluation of the changes on the supernumerary teeth. The study included 90 skulls and 81 jaws of both sexes with average age 20-60 years. Supernumerary teeth were prepared for SEM for analyzing dental tissues. Six supernumerary teeth were found, among them five mesiodensand one paramolar. The frequency of hyperdontia in these skeletal remains is 2,1%. Mesiodens is different morphologically from the incisor it replaced and took part in occlusal contacts during mastication. Paramolar is different morphologically from molar teeth and it did not take part in occlusal contacts during mastication because of its low adherence for bone tissues and small dimensions

Uticaj promene dužine slobodnog sedla na promenu napona retencionih zuba i spoja jednostrane kompleksne parcijalne proteze

Background/Aim. Different types of dental restorations are used for the therapy of unilateral free-end saddle edentulism. Unilateral complex partial denture is one of the indications for the Kennedy class II partial edentulism. The abscence of major connector and denture plate is an advantage compared to the conventional restorations, because of better comfort and shorter period of adaptation. The aim of the study was to analyse the influence of free-end saddle length change on the behaviour of unilateral complex partial denture supporting structures. Methods. Stress levels of the canine and the first premolar as retentional teeth and the attachments were tested under the influence of physiological forces with the loading point shifting distally in relation to the saddle length change. A virtual real size 3D model of the fixed part of the restoration (the canine and the first premolar with milled crowns) was created using the CATIA computer program. It was connected to the mobile part of partial denture with the SD snap in latch attachment. Mobile part of the restoration was designed in the region of 2, 3 and 4 lateral teeth (second premolar, first, second and third molar). By using the finite element method (FEM) stress levels analysis was performed under the load of physiological forces of 150 N in the free-end saddle teeth zone. Results. The results of analysis show that physiological forces cause a different stress distribution on the abutment teeth and the attachment, depending on the saddle length. Conclusion. The stress level values obtained for the abutment teeth as well as the attachment are far lower than the marginal ones. The behaviour of the system changes under this defined stress, but no plastic deformation occurs.Uvod/Cilj. U terapiji jednostrano slobodnog sedla koriste se različiti oblici zubnih nadoknada. Jednostrana kompleksna parcijalna proteza (JKPP) jedna je od indikacija za bezubost klase Kenedi II. Odsustvo velike spojnice i protezne ploče predstavlja prednost u odnosu na konvencionalne nadoknade zbog boljeg komfora i kraćeg perioda adaptacije. Cilj rada bio je analiza uticaja promene dužine slobodnog sedla na ponašanje potpornih struktura JKPP. Metode. Ispitivani su naponi očnjaka i prvog premolara kao retencionih zuba i veze (spoja) pod dejstvom fizioloških sila sa pomeranjem tačke opterećenja distalno, u zavisnosti od dužine sedla. Primenom kompjuterskog programa CATIA u realnoj veličini urađen je virtulni 3D model fiksnog dela nadoknade (očnjak i prvi premolar sa namenskim krunama) koji je veza SD snap in latch priključena na mobilni deo parcijalne proteze. Mobilni deo nadoknade postavljen je u predelu dva, tri, odnosno četiri bočna zuba (drugi premolar, prvi, drugi i treći molar). Primenom metode konačnih elemenata obavljena je analiza naponskih stanja pri opterećenju fiziološkim silama od 150 N u predelu zuba slobodnog sedla. Rezultati. Analiza proračuna pokazala je da pod dejstvom fizioloških sila dolazi do različite raspodele napona na retencione zube i spoj u zavisnosti od dužine sedla. Zaključak. Dobijene vrednosti za napone kako na retencionim zubima, tako i na spoju, daleko su manje od graničnih. Pri zadatim naponima dolazi do promene ponašanja, ali ne i do plastične deformacije sistema

Multiformni glioblastom lokaliziran u motornom korteksu: specifičnosti u odnosu na gliome niskog stupnja iste lokalizacije - analiza serije od šezdeset bolesnika

The verified presence of a glioblastoma multiforme (GBM ) tumor in the motor area of the brain, in a patient lacking preoperative neurological deficit, offers no certainty that the tumor can be radically removed without the possibility of causing postoperative motor deficit. We present a series of 60 patients hospitalized at the Clinical Department of Neurosurgery, Clinical Center of Serbia in Belgrade between October 2011 and February 2015, harboring tumors located within and in the vicinity of the motor zone of the brain. By using Karnofsky‘s index (KI), the pre- and postoperative conditions of the patients were evaluated. Regarding electrical stimulation of the motor cortex, significantly lower values of the electrical current intensity, frequency, and pulse wave duration (p<0.01) were needed for triggering motor response in case of GBM tumor compared to a slowly growing tumor (low-grade). Patients with low-grade gliomas (LGG) had statistically significantly higher KI values pre- and postoperatively than patients with GBM (p<0.01). Using electrical stimulation of the cortex, a higher grade of resection of LGG could be achieved as compared with the group presenting with GBM (c2=5.281; df=1; p<0.05). Our findings and review of the results reported by other authors underline the necessity of routine application of electrical stimulation of the cerebral cortex in order to identify the primary motor field (M1).Jasna prezentacija tumora mozga u području motorne zone kod bolesnika koji prijeoperacijski nisu imali slabost ekstremiteta nije jamstvo da se on može radikalno odstraniti bez poslijeoperacijskog neurološkog deficita. Prikazujemo niz od 60 ispitanika sa supratentorijalnim tumorima lokaliziranim u i oko motorne zone mozga, koji su hospitalizirani na Institutu za neurokirurgiju KCS u Beogradu u razdoblju od listopada 2011. do veljače 2015. godine. Procjena prije- i poslijeoperacijskog stanja bolesnika je vrednovana ljestvicom Karnofski indeksa (KI). Iz serije su isključeni bolesnici s recidivom tumora i bolesnici čiji je KI kod prijma bio manji od 70. Tijekom procedure elektrostimulacije motornog korteksa potrebne su značajno manje vrijednosti jačine struje, frekvencije i pulsnog vala (p<0,01) za izazivanje motornog odgovora u slučaju postojanja tipa tumora multiformnog glioblastoma (glioblastoma multiforme, GBM ) u odnosu na spororastuće gliome (niskog stupnja) mozga. Nađena je statistički značajna razlika u prije- i poslijeoperacijskim vrijednostima KI (F=48,856; df=1; p<0,01; Eta2=0,457), naime, bolesnici s gliomima niskog stupnja imali su statistički značajno veću vrijednost KI prije- i poslijeoperacijski u odnosu na vrijednosti KI kod skupine bolesnika s GBM (p<0,01). Uporabom elektrostimulacije korteksa postignut je veći stupanj radikalnosti kirurške resekcije glioma niskog stupnja u odnosu na skupinu bolesnika s GBM (c2=5,281; df=1; p<0,05). Kirurgija tumora lokaliziranih u motornom korteksu predstavlja izazov zbog pratećeg rizika od de novo nastanka motornog deficita. Naši rezultati kao i rezultati drugih autora pokazuju neophodnost rutinske primjene direktne elektrostimulacije moždane kore radi identifikacije primarnog motornog polja (M1)

Primjena polutrajnih i konvencionalnih cemenata s modificiranom tehnikom cementiranja u dentalnoj implantologiji

Objectives: The aim of this study was to evaluate the influence of artificial ageing on the retention force of original semipermanent cements, as well as the possibility of using conventional cements for semipermanent cementation with adequate modification of the cementing protocol. Material and methods: Forty CoCrMo alloy crowns were divided in four groups (each group n=10) and fixed with two semipermanent cements (resin-based and glass ionomer-based cements) and one conventional (zinc phosphate), using conventional and modified cementation techniques on titanium abutments. The samples were stored in humid conditions for 24 hours at 37°C and subjected to thermocycling (500 cycles) and mechanical cyclic loading (7 days, 3, 6, 9 and 12 months function simulation). The cast crowns were removed and the retention force was recorded. Results: The highest initial retention force measured was for zinc-phosphate cement - conventional cementing (198,00±61,90 N), followed in descending order by zinc-phosphate cement - modified cementing technique (152,00±45,42 N), long term temporary cement – GC Fuji Temp LT (57,70±20,40 N), and semipermanent cement - Te-lio CS Cem Implant (56,10±18,68 N). After 12 months, the highest retention force measured was for zinc-phosphate cement - conventional cementing (88, 90±14, 45 N), followed by zinc-phosphate cement – modified cementing (48, 15±14,41N), semipermanent cement GC Fuji Temp LT (16,55±3,88 N) and Telio CS Cem Implant (15,55±5,52 N). Conclusions: Zinc-phosphate cement - modified cementing technique and original semipermanent cements can be recommended for conditional permanent cementing of implant supported crowns. Clinical relevance: The use of semipermanent cements and zinc-phosphate cement - modified cementing technique provides a predictable retrievability of implant-supported crowns.Cilj: Željelo se ispitati kakav je utjecaj umjetnoga starenja na retencijsku silu originalnih (polutrajnih) semipermanentnih cemenata i mogućnost upotrebe konvencionalnih cemenata za polutrajno pričvršćivanje, uz odgovarajuću prilagodbu protokola cementiranja. Materijal i metode: U četiri skupine raspoređeno je 40 krunica izrađenih od Co-Cr-Mo legure (svaka skupina n = 10) i fiksiranih dvama polutrajnim cementima (cementi na bazi smola i staklenoionomera) i jednim konvencionalnim (cink-fosfatni cement), učvršćene konvencionalnom i prilagođenom tehnikom cementiranja na titanijevim nadogradnjama (engl. abutment). Uzorci su bili 24 sata pohranjeni u vlažnim uvjetima na temperaturi od 37 °C nakon čega su podvrgnuti termocikliranju (500 ciklusa) i mehaničkim cikličnim opterećenjima (simulacija 7 dana, 1, 3, 6, 9 i 12 mjeseci u funkciji). Krunice su uklonjene i zabilježena je retencijska sila. Rezultati: Najvišu inicijalnu retencijsku silu pokazao je cink-fosfatni cement – konvencionalno cementiranje (198,00 ± 61,90 N), a slijede ga u silaznom nizu cink-fosfatni cement – prilagođena tehnika cementiranja (152,00 ± 45,42 N), dugotrajni privremeni cement – GC Fuji LT (57,70 ± 20,40 N) i semipermanentni cement Telio CS (56,10 ± 18,68 N). Poslije 12 mjeseci najviša retencijska sila izmjerena je za cink-fosfatni cement – konvencionalno cementiranje (88, 90 ± 14,45 N), a slijede cink-fosfatni cement – prilagođena tehnika cementiranja (48,15 ± 14,41 N) te semipermanentni cementi GC Fuji Temp LT (16,55 ± 3,88 N) i Telio CS Cem Implant (15,55 ± 5,52 N). Zaključak: Cink-fosfatni cement – prilagođena tehnika cementiranja i originalni polutrajni cementi (semipermanentni) mogu se preporučiti za uvjetno trajno cementiranje krunica postavljenih na implantate jer omogućuje optimalnu mogućnost uklanjanja krunica postavljenih na implantate

Skenirajuća elektronska mikroskopija dental D materijala za izradu estetskih kukica

With a need for noninvasive methods and better esthetics solutions in dentistry, in a last few years, series of new materials in production of partial dentures turns up. Examination is done on Dental D® material for esthetic clasps. Some technical characteristics of the material are presented along with a production technique and also with our research. One of the ways for examination of material structure is scanning electron microscopy. With examination of Dental D® materials by micrographic methods, we reached some positive results, which may take noninvasive methods and esthetic in dentistry on a higher level.Poslednjih godina se sa potrebom za neumornom metodama i boljim estetskim rešenjima u stomatologiji, pojavio niz novih materijala koji se koriste u izradi parcijalne skeletirane proteze. Ispitivan je Dental D materijal za izradu estetski kukica. U radu su predstavljene neke tehničke karakteristike materijala, tehnika izrade, a i naša ispitivanja ovog materijala. Skenirajuća elekronska mikroskopija je jedan od načina da se ispita površina i struktura materijala. Ispitivanjem Dental D® materijala mikrografskim metodama došli smo do pozitivnih rezultata koji mogu doprineti da se neinvazrvnost i estetika u stomatologiji podignu na viši nivo

Primena 'SKY PLAN X' sistema u planiranju ugradnje implantata kod terminalne obostrane bezubosti gornje vilice

An increasing patients' requirements put the dental implantology in the position where it is necessary to apply new digital technologies. In the paper, the case of 60 years old patient was presented, who was referred for prosthetic rehabilitation of maxilla with the fixed denture. After medical examination and upon X-rays imaging it was revealed that teeth 12, 11 and 22 can be used for prosthetic purposes where mutual tooth gaps in toothless jaw can be treated with implant supported fixed bridges. Because of limitation values of vertical and horizontal dimension of the bone, 3D orthopantomography was made as well as planning for implant position applying 'Sky Plan X System' manufactured by Bredent, which belongs to the group of static open systems. Upon surgical stent was made, implants were placed using 'flap less' method on solely available 15, 13, 23 and 26 positions. Three months afterwards final metal-ceramic denture was fixed over implant abutments posts. Computer guided implant application facilitates surgery-prosthetics treatment of the patient and it is mostly recommended for so called 'limitation cases' where our possibilities for placing implants are limited by anatomical factors.Porast estetskih zahteva pacijenata stavlja dentalnu implantologiju u poziciju u kojoj je neophodna primena modernih digitalnih tehnologija. U radu je prikazan slučaj pacijenta starog 60 godina koji se javio radi protetske rehabilitacije gornje vilice fiksnim protetskim radom. Kliničkim pregledom i rentgenskom analizom utvrđeno je da se protetski mogu iskoristiti zubi 12, 11 i 22, a da se obostrana terminalna bezubost zbrine implantatno nošenim mostovima. Zbog graničnih vrednosti kako vertikalne, tako i horizontalne dimenzije kosti, pacijentu je urađen 3D ortopan snimak i planiranje pozicije implantata ' Sky plan X' sistemom, proizvođača Bredent, koji spada u grupu statičkih otvorenih sistema. Nakon izrade hirurškog stenta urađena je ugradnja implantata 'flap less' metodom na jedino mogućim pozicijama 15, 13, 23 i 26. Nakon tri meseca implantati su opterećeni i urađen definitivni metal-keramički protetski rad. Kompjuterom vođena ugradnja implantata znatno olakšava hirurško protetski tretman pacijenta i posebno je indikovana kod tzv. 'graničnih slučajeva' gde su nam mogućnosti za ugradnju implantata limitirane anatomskim faktorima

Real-time thermographic analysis of low-density bone during implant placement: a randomized parallel-group clinical study comparing lateral condensation with bone drilling surgical technique

Objectives: To compare the effect of two surgical techniques, lateral condensation and bone drilling, on changes in temperature of the adjacent low-density bone during implant placement into posterior maxilla and to investigate the influence of the host factors - age, gender, region of implantation, bone density, and thickness of the cortical bone at the recipient sites. Material and methods: Local bone temperature was measured thermographically during implant placement into posterior maxilla following lateral bone condensing (test group) or bone drilling (controls). The main study outcomes were baseline bone temperature prior to implantation and maximum bone temperature recorded during implantation. Early implant success was evaluated after 6 months of healing. Results: A total of 40 implants were randomly allocated to test and control groups and placed into maxillary premolar and/or molar region of 18 participants of both genders and average age of 51.74 years. All recorded bone temperatures were below the threshold for thermal necrosis. Although both groups showed significant increase in bone temperature during implant placement procedure (P lt = 0.0005), it was significantly higher for bone condensing compared with drilling (P lt = 0.0005; 3.79 +/- 1.54 degrees C; 1.91 +/- 0.70 degrees C respectively). No host factor was singled out as a significant predictor of bone temperature changes, although trend of higher increase was observed in young patients, regardless of gender, during implant placement procedure into maxillary first premolar region with bone density type 3 and cortical layer thicker than 1 mm. Early implant success rate after 6 months follow-up was 100%. Conclusion: Although both surgical techniques, bone condensing and bone drilling, can be considered safe regarding their thermal effect on the bone of posterior maxilla, bone drilling is associated with fewer local bone heating during implantation. Host factors do not affect the bone thermal changes significantly

An in vitro study of temperature changes in type 4 bone during implant placement: bone condensing versus bone drilling

Objective. The aim of this study was to compare changes in temperature of the surrounding bone at various osteotomy depths during implant site preparation by bone condensing and by bone drilling as well as the dynamics of their change. Study design. In the present "in vitro" study, pig ribs with uniform thickness of cortical bone of 2 mm were used. Lateral bone-condensing (experimental group) and bone-drilling techniques (control group) were performed. Temperature changes were recorded at a distance of 0.5 mm from the final test osteotomy by 3 thermocouples at the depths of 1, 5, and 10 mm in tripod configuration. Data were collected from 48 measurements, 24 for each group. Results. Significantly higher mean temperature increase at the depth of 5 mm was observed during bone drilling compared with bone condensing, whereas for the depths of 1 and 10 mm differences were not significant between the 2 surgical techniques. During bone condensing, the mean temperature rise was continuously decreasing with increasing depth of osteotomies, whereas during bone drilling the mean temperature rise was first increased and reached a peak at the depth of 5 mm and then began to decrease with increasing depth of the osteotomies. Conclusions. The bone-condensing technique applied in the jaw bone class D4 offers an advantage over bone drilling because it generates a significantly smaller amount of heat. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011; 112: 28-33