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Aim: To assess the distance between the inferior alveolar canal and the roots of the mandibular second molar and the mandibula and cortex in a Saudi Arabian subpopulation through existing CBCT images. Materials and Methods: This retrospective study was performed based on 120 patients CBCT images in five age groups.The distances (D1 and D2) between the buccal cortex (BC), lingual cortex (LC), and mandibular molars and the distances (D3) between the root apices and inferior alveolar nerve canal (IANC) were measured for each dental root on the right and left of the mandible with the help of Vision iCAT software. A radiology specialist with a gap of 15 days twice carried out the measurements. Statistical analysis was carried out with the help of SPSS 24. to analyse variability Chi-square analysis was done, and the p value was fixed at > 0.05. To check inter-person variability, Cohen’s variability was fixed at 0.8. Results: The distance between the outer surface of the buccal cortical plate and the buccal root surface ranged between 3.8 and 5.7 mm, whereas the distance between the root apices of the mandibular molars and the IANC ranged between 4.8 and 3.5 mm. The distance from the outer surface of the lingual cortical plate to the lingual root surface varied between 1.2 and 2.8 mm. The mean distance between the root apices and IANC increased with age, more so in males than females. Conclusions: Even though this study was conducted on a small sample size, it will help the dental practitioners in planning endodontic procedures, surgical extractions, and implant placements, and it should be repeated with a higher number of images., Objetivo: Evaluar la distancia entre el canal alveolar inferior y las raíces del segundo molar mandibular, y la mandíbula y la corteza en una subpoblación de Arabia Saudita a través de imágenes CBCT existentes. Materiales y Métodos: Este estudio retrospectivo se realizó con base en imágenes CBCT de 120 pacientes en cinco grupos de edad. Las distancias (D1 y D2) entre la corteza bucal (BC), la corteza lingual (LC) y los molares mandibulares y las distancias (D3) entre los Se midieron los ápices radiculares y el canal del nervio alveolar inferior (IANC) para cada raíz dental a la derecha e izquierda de la mandíbula con la ayuda del software Vision iCAT. Un especialista en radiología, con un intervalo de 15 días, realizó dos veces las mediciones. El análisis estadístico se realizó con la ayuda del SPSS 24. Para analizar la variabilidad se realizó un análisis de Chi-cuadrado y el valor p se fijó en > 0,05. Para comprobar la variabilidad entre personas, la variabilidad de Cohen se fijó en 0,8. Resultados: La distancia entre la superficie exterior de la placa cortical bucal y la superficie de la raíz bucal osciló entre 3,8 y 5,7 mm, mientras que la distancia entre los ápices radiculares de los molares mandibulares y el IANC osciló entre 4,8 y 3,5 mm. La distancia desde la superficie exterior de la placa cortical lingual hasta la superficie de la raíz lingual varió entre 1,2 y 2,8 mm. La distancia media entre los ápices de las raíces y la IANC aumentó con la edad, más en hombres que en mujeres. Conclusión: Aunque este estudio se realizó con un tamaño de muestra pequeño, ayudará a los odontólogos a planificar procedimientos de endodoncia, extracciones quirúrgicas y colocación de implantes, y debe realizarse con más números

Objetive: The aim of this study was to determine the prevalence, demographics, and root configuration of C-shaped canals of mandibular molars by means of cone beam computed tomography in the population of the Metropolitan Region, Chile. Material and Methods: 912 molars (456 first and 456 second molars) resulting from the analysis of 228 mandibular CT scans were evaluated. The root configuration was established by means of a panoramic reconstruction and axial tomographic sections, classifying the presence and type of canals through the analysis of five sections along the root. Data were statistically analyzed using a 5% confidence interval. Results: Of the 912 molars analyzed, 70 were classified as C-shaped canals (7.68%), corresponding to 58.33% of those molars that presented fused roots. 95.7% of this root canal configuration was observed in lower second molars, occurring more frequently in females (n=45, 64.29%). 45.65% of the cases that presented C-shaped canals were bilateral and the most frequent configuration was C3 (n=401, 66.63%) according to the Melton classification.Conclusion: The C-shaped canals of the mandibular molars in the studied population were observed mainly in second molars, showing a clear predilection among females and a high percentage of bilaterality. The presence of fused roots significantly increases the possibility of finding this type of root configuration.K, Objetivo: El objetivo del presente estudio fue determinar, por medio de tomografía computarizada de haz cónico, la prevalencia, demografía y configuración radicular de los conductos en forma de C de molares inferiores en la población de la Región Metropolitana, Chile. Material y Métodos: 912 molares (456 primeros y 456 segundos molares) resultantes del análisis de 228 tomografías mandibulares fueron evaluados. Mediante una reconstrucción panorámica y cortes tomográficos axiales se estableció la configuración radicular, clasificando la presencia y tipo de conducto por medio del análisis de 5 cortes a lo largo de la raíz. Los datos fueron analizados estadísticamente con un intervalo de confianza del 5%. Resultados: De los 912 molares analizados, 70 fueron clasificados como conductos en forma de C (7.68%), corres-pondiendo al 58.33% de aquellos molares que presentaron raíces fusionadas. El 95.7% de esta configuración de conductos fue observada en segundos molares inferiores, presentándose con mayor frecuencia en mujeres (n=45, 64.29%). El 45.65% de los casos que presentaron conductos en C se manifestaron bilateralmente y la configuración más frecuente observada fue la C3 (n=401, 66.63%) según la clasificación de MeltonConclusión: Los conductos en forma de C de los molares mandibulares en la población estudiada fueron observados principalmente en segundos molares, marcando una clara predilección por el sexo femenino y un alto porcentaje de bilateralidad. La presencia de raíces fusionadas aumenta significativamente la posibilidad de encontrar este tipo de configuración radicular.

Purpose: The goal was to study the effects of early cervical headgear treatment on maxillary and mandibular dental arch area, shape and interarch dimensions. Methods: The total study group comprised 67 children aged 7.6 years (standard deviation 0.3) with Angle class II malocclusion collected between 1992 and 1996. The children were randomly divided into two groups of equal size. In the first group, cervical headgear treatment was started immediately and undertaken for 2 years. The remaining patients served as untreated controls. Dental casts were taken and scanned at the beginning of treatment (T0) and at the 2‑year (T1) and 4‑year follow-up (T2). Three-dimensional landmarks describing the positions of maxillary and mandibular incisors, canines, first and second premolars and first molars were used to calculate and visualize the maxillary and mandibular dental arch area and shape using the polynomial equation y = Ax⁶ + Bx². Results: Significant changes in the shape and area of both maxillary and mandibular dental arches were induced with cervical headgear. The headgear increased dental arch area, sagittal dimensions at the mid-sagittal line and transversal dimensions at all of the measured levels in both dental arches compared to the control group. Conclusions: Cervical headgear is an effective treatment device to gain space in both dental arches. Furthermore, when used as an early phase treatment, relapse is relatively small compared to the gained space., Zusammenfassung Zielsetzung: Ziel dieser Studie war es, die Auswirkungen einer frühen zervikalen Headgear-Behandlung auf den Bereich des Ober- und Unterkieferzahnbogens, die Form und die Interbogendimensionen zu untersuchen. Methoden: Die Studiengruppe umfasste insgesamt 67 Kinder im Alter von 7,6 Jahren (Standardabweichung 0,3) mit Angle-Klasse-II-Malokklusion, die zwischen 1992 und 1996 behandelt wurden. Die Kinder wurden randomisiert in 2 gleich große Gruppen aufgeteilt. In der ersten Gruppe wurde sofort mit der zervikalen Headgear-Behandlung begonnen und sie wurde 2 Jahre lang durchgeführt. Die übrigen Patienten dienten als unbehandelte Kontrolle. Zu Beginn der Behandlung (T0), beim 2‑ (T1) und beim 4‑Jahres-Follow-up (T2) wurden Abdrücke genommen und gescannt. Dreidimensionale Landmarken zur Darstellung der Positionen von Schneidezähnen, Eckzähnen, ersten und zweiten Prämolaren und ersten Molaren im Ober- und Unterkiefer wurden zur Berechnung und Visualisierung des Bereichs und der Form des Zahnbogens des Ober- und Unterkiefers unter Verwendung der Polynomgleichung y = Ax⁶ + Bx² verwendet. Ergebnisse: Mit dem zervikalen Headgear wurden signifikante Veränderungen in Form und Fläche sowohl der Ober- als auch der Unterkieferzahnbögen induziert. Das Headgear vergrößerte im Vergleich zur Kontrollgruppe die Zahnbogenfläche, die sagittalen Dimensionen an der mittleren sagittalen Linie und die transversalen Dimensionen auf allen gemessenen Ebenen in beiden Zahnbögen. Schlussfolgerungen: Das zervikale Headgear ist eine wirksame Behandlungsvorrichtung, um in beiden Zahnbögen Platz zu gewinnen. Wenn sie als Frühphasentherapie eingesetzt wird, ist das Rezidiv im Vergleich zum gewonnenen Platz relativ gering.

Dental enamel thickness, topography, growth and development vary among hominins. In Homo, the thickness of dental enamel in most Pleistocene hominins display variations from thick to hyper-thick, while Neanderthals exhibit proportionally thinner enamel. The origin of the thin trait remains unclear. In this context, the Middle Pleistocene human dental assemblage from Atapuerca-Sima de los Huesos (SH) provides a unique opportunity to trace the evolution of enamel thickness in European hominins. In this study, we aim to test the hypothesis if the SH molar sample approximates the Neanderthal condition for enamel thickness and/or distribution. This study includes 626 molars, both original and comparative data. We analysed the molar inner structural organization of the original collections (n = 124), belonging to SH(n = 72) and modern humans from Spanish origin (n = 52). We compared the SH estimates to those of extinct and extant populations of the genus Homo from African, Asian and European origin (estimates extracted from literature n = 502). The comparative sample included maxillary and mandibular molars belonging to H. erectus, East and North African Homo, European Middle Pleistocene Homo, Neanderthals, and fossil and extant H. sapiens. We used high-resolution images to investigate the endostructural configuration of SH molars (tissue proportions, enamel thickness and distribution). The SH molars exhibit on average thick absolute and relative enamel in 2D and 3D estimates, both in the complete crown and the lateral enamel. This primitive condition is shared with the majority of extinct and extant hominin sample, except for Neanderthals and some isolated specimens. On the contrary, the SH molar enamel distribution maps reveal a distribution pattern similar to the Neanderthal signal (with thicker enamel on the lingual cusps and more peripherally distributed), compared to H. antecessor and modern humans. Due to the phylogenetic position of the SH population, the thick co, Ministerio de Ciencia e Innovación (MICINN), Junta de Castilla y León, British Academy, Leakey Foundation, Fundación Atapuerca, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

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Aims and objectives: To investigate the various major and minor reasons for extraction of permanent teeth, taking into consideration various factors such as age, gender, type of teeth being extracted, extent of pathology and non willingness of the patient to save the teeth.Materials and methods: This study consisted of 1608 patients out of which 840 were males and 768 were females. All these patients had reported to the College of Dental Science & Hospital, Rau, Indore, for extraction of teeth during October 2011 to May 2012. All possible reasons for extraction of teeth were considered and noted down in a preformed chart.Results: A total of 1790 teeth were extracted in 1608 patients. Males underwent more extractions as compared to females. Middle age group patients of 30e40 years of age had the maximum number of extractions. Dental Caries was the main reason for extraction of teeth.Conclusion: Dental Caries and Periodontitis still remain the two most important reasons for extraction of teeth. Knowing the etiologic factors will help us treat and prevent them so as to improve the dental health of the general population.

Introduction/Objective: Molar-incisor hypomnineralization (MIH) is relatively common developmental anomaly characterized by hypomineralized enamel defects in the first permanent molars and incisors. The aim of this study was to determine the prevalence of hypomineralization of the first permanent molars and incisors in children aged eight and 10 years who live in the northern part of Kosovo and Metohija. Methods: The study included 712 respondents, 289 of whom aged eight (40.6%) and 423 of whom aged 10 years (59.4%). Criteria according to Weerheijm were used for diagnosis of hypomineralization and the severity of changes was determined. Results: The frequency of hypomineralized changes in the first permanent molars and incisors of the examined children in this area was 12.2%. It was lower in children aged eight years (10.7%) compared to those aged 10 (13.2%). Demarcated enamel opacity was more common in younger children, whereas both atypical restoration and tooth extraction due to hypomineralization were more common in older children. Mild form is more common in children aged eight years, whereas both severe form and severe form with extracted teeth are more common in children aged 10 years. The results indicate that the first permanent molars were most commonly affected by MIH changes. Conclusion: The percentage of the respondents with MIH changes in the northern part of Kosovo and Metohija, which is 12.2%, is not negligible and points to the necessity of early diagnosis in order to prevent and reduce the complications of the condition by timely prevention and treatment., Uvod/Cilj: Hipomineralizacija kutnjaka i sekutića (HKS) relativno je česta razvojna anomalija koja se karakteriše pojavom hipomineralizovanih defekata gleđi na prvim stalnim kutnjacima i sekutićima. Cilj ovog rada bio je da se ispita učestalost hipomineralizacije na prvim stalnim kutnjacima i sekutićima kod dece uzrasta osam i deset godina na području severnog dela Kosova i Metohije. Metode: U istraživanju je bilo uključeno 712 ispitanika – 289 uzrasta osam godina (40,6%) i 423 (59,4%) uzrasta deset godina. Za dijagnozu oboljenja primenjeni su kriterijumi po Weerhejim-u i određen je stepen izraženosti promena. Rezultati: Učestalost hipomineralizovanih promena na prvim stalnim kutnjacima i sekutićima kod ispitivane dece na ovom području iznosio je 12,2%. Kod dece od osam godina učestalost ovih promena je manja (10,7%) u odnosu na ispitanike od deset godina (13,2%). Ograničena zamućenost gleđi bila je učestalija kod dece mlađeg uzrasta, dok je kod dece starijeg uzrasta učestalija atipična restauracija i ekstrakcija zuba kao posledica hipomineralizacije. Blaga forma je učestalija kod dece od osam godina, dok je kod dece od deset godina učestalija teška forma, kao i teška forma koja uključuje i ekstrahirane zube. Rezultati pokazuju da su prvi stalni kutnjaci najčešće zahvaćeni hipomineralizovanim promena. Zaključak: Procenat od 12,2% ispitanika sa promenama HKS na području severnog dela Kosova i Metohije nije zanemarljiv. Ovakvo stanje ukazuje na neophodnost rane dijagnostike da bi se blagovremenom prevencijom i terapijom sprečile i ublažile komplikacije ovog oboljenja.

Studies in zoo-archaeological Neolithic contexts is the study of early animal domestication in relation to humans transitioning into a more sedentary species. Research and documentation are vital for reconstructing the mechanisms behind the threshold event. In this thesis, teeth of Suidae have been documented, analysed and compared osteologically and interpreted cross-culturally. In addition, aDNA, isotope, coat colour and physical mammal size affecting factor studies are presented to contextualise this thesis. Primary osteological methods are Mandibular Wear Stage (MWS), Linear Enamel Hypoplasia (LEH) recordings and lower jaw third molar (M3) length measurement. These methods can detect biometric domestication markers. The analysed Suidae teeth are from the Middle Neolithic site of Ajvide, Gotland, Sweden. A collection of modern wild boar act as Control sample. These teeth are compared primarily with known domestic pig teeth sample statistics from the British Late Neolithic site of Durrington Walls, Wiltshire, United Kingdom. Results indicate that the Middle Neolithic Pitted Ware culture (PWC) on Gotland hunted during winter and kept limited numbers of captive wild boars as totemic animals (pets) possibly bound to land and ancestry. However, an exact reconstruction of the PWC pig pet keeping practices are uncertain due to human-pig relationships being highly dynamic. Intensified pig hunting, not pet keeping should be considered early domestication. Domestication carries with it detectable biometric markers, which seem to be rare in the Neolithic. The cross-cultural comparisons on traditional pig ‘low-intensity husbandry’ can attest to a human-pig relationship of hunter-gatherers keeping captive wild animals. The pig was not a staple food for the PWC and thus not intensively hunted, rather pigs were rare ritualistic commodities and likely highly praised. Perpetuating this human-pig relationship could have been maintained by PWC ‘big men’ that engaged in socio-politi, Studier i neolitiska zoo-arkeologiska sammanhang är undersökningar av tidig domesticering av djur i förhållande till mänsklighetens övergång till en mer stillasittande art. Forskning och dokumentation är avgörande för att rekonstruera mekanismerna bakom övergången. I denna uppsats har svintänder dokumenterats, analyserats och jämförts osteologiskt och tolkats tvärkulturellt. Studier i aDNA, isotop, pälsfärg och fysiska storleksfaktorer hos däggdjur presenteras också för att kontextualisera denna uppsats. Primära osteologiska metoder är tandslitage i underkäke (MWS), linjär emaljhypoplasi (LEH) och underkäkens tredje molar (M3) mätningar. Dessa metoder kan finna biometriska domesticeringsmarkörer. De analyserade svintänderna kommer ifrån den mellanneolitiska lokalen Ajvide, Eksta socken, Gotland. En samling moderna vildsvin agerar kontrollmaterial. Dessa tänder jämförs i första hand med kända domesticerade stenåldersvin från den Brittiska senneolitiska lokalen Durrington Walls, Wiltshire, Storbritannien. Resultaten indikerar på att den mellanneolitiska gropkeramiska kulturen (GRK), jagade på Gotland under vinterhalvåret och tog tillfånga ett begränsat antal svin som husdjur (totemdjur). Troligen togs svin tillfånga av olika ’hus’ till följd av att svinet var bundet till land och förfäder. En exakt rekonstruktion av GRKs svinhållningspraktik är dock osäkert på grund av att människo-svin relationer är dynamiska. Intensifierad svinjakt, inte tillfångatagandet av enstaka djur bör betraktas som tidig domesticering. Domesticering medför speciella biometriska markörer som är ovanligare i neolitisk tid. De tvärkulturella jämförelserna i traditionell "lågintensiv svinhållning" kan intyga på ett sådant förhållande mellan jägare-samlar grupper och vildsvin. Även om svinet inte var en basföda åt GRK, och därmed inte intensivt jagade, var svinen sällsynta ritualistiska handelsvaror och troligen högt värdesatta. Gropkeramiska "stormän" kan ha varit de drivande bakom denna praktik.

This experimental research aimed to have and cultivate stem cells from pulp tissue of impacted third molars, from 20 volunteers of both genders aged between 18 and 22 years who meet the inclusion criteria and gave their consent to voluntary participation.The laboratory method comprises successive steps that begin with obtaining the sample imediata pulp for conservation in the standardized average Dullbecos Modified Eagle Medium® culture supplemented with fetal bovine serum and antibiotics solution. The technique used to obtain stem cells by enzymatic digestion was given by Gronthos et al; the expected density of cell culture was achieved after 9 days to proceed to trypsinization and continue their cultivation; then the cell passes every 3 days achieving a cell confluence of 95% at 15 days were done.Results in cell confluence is obtained by counting cells suspended in the culture medium. Cell confluence at 3 days of culture was 20% and the cells adquire ovoid, after 6 days was 40% with further stabilization in its fibroblastoid shape, at 9 days was 85% with similar appearance to fibroblasts and 15 days was 95% while retaining their phenotype.It is concluded that the pulp tissue impacted third molars is of one of the main sources of stem cells easy access, being possible to characterization and culture., La presente investigación experimental tuvo como propósito obtener y cultivar células madre del tejido pulpar de terceros molares impactados, procedentes de 20 voluntarios, de ambos géneros entre 18 y 22 años, que cumplen los criterios de inclusión y firmaron su consentimiento de participación voluntaria.El procedimiento laboratorial comprende pasos sucesivos que se inician con la obtención de la muestra pulpar para su inmediata conservación en el medio de cultivo estandarizado Dullbecos Modified Eagle Medium®, complementado con suero fetal bovino y solución de antibióticos. La técnica empleada para la obtención de células madre fue por digestión enzimática propuesta por Gronthos et al; la densidad del cultivo celular esperada se logró a los 9 días para proceder a la tripsinización y continuar con el cultivo; luego se realizaron los pases celulares cada 3 días logrando una confluencia celular del 95% a los 15 días.En los resultados, la confluencia celular se obtiene por el contaje de células suspendidas en el medio de cultivo. La confluencia celular a los 3 días de cultivo fue 20% y las células adquieren forma ovoide, a los 6 días fue 40 % con mayor estabilización en su forma fibroblastoide, a los 9 días fue 85% con aspecto semejante a los fibroblastos y a los 15 días fue 95% conservando su fenotipo.Se concluye que el tejido pulpar de terceros molares impactados es una de las principales fuentes de células madre de fácil acceso, siendo posible su caracterización y cultivo.

Objective The mental foramen (MF) hosts main neurovascular structures, making it of crucial importance for surgical procedures. This study aimed to analyze the factors influencing the dimensions and location of the MF. Materials and methods Cone beam computed tomography (CBCT) scans of 344 patients were examined for MF dimensions, as well as for the distances from the MF to the alveolar crest (MF-MSB), and to the inferior mandibular border (MF-MIB). Results Gender, mandibular side and presence of accessory mental foramina (AMF) significantly influence MF area. Males, left hemimandibles, and hemimandibles with no AMF had a higher rate of large MF areas (B = − 0.60; p = 0.003, females; B = 0.55; p = 0.005; B = 0.85; p = 0.038). Age, gender and dental status significantly influence MF-MSB distance. The distance decreased as age increased (B = −0.054; p = 0.001), females showed a lower rate of long MF-MSB distances (B = −0.94, p = 0.001), and dentate patients showed a higher rate of long MF-MSB distances (B = 2.27; p = 0.001). Age, gender and emerging angle significantly influenced MF-MIB distance. The distance decreased as age and emerging angle increased (B = −0.01; p = 0.001; B = −0.03; p = 0.001), and females had a lower rate of long MF-MIB distances (B = −1.94, p = 0.001). Conclusions General and local factors influence the dimensions and location of MF. MF dimensions are influenced by gender, mandibular side, anteroposterior position, and the presence of AMF. Distance from MF to alveolar crest is influenced by gender, age and dental status, while the relative MF position is influenced by age and dental status. CBCT images make it possible to analyze the MF in order to avoid complications during surgical procedures

Tooth colored all ceramic restorations have been the treatment preference of many patients for esthetics and biocompatibility. This study aimed to test the fracture resistance of posterior ceramic onlays milled with computer-aided design and computer aided manufacturing (CAD/CAM) machines.The effects of material type, preparation design, and tooth substrate were evaluated using a full-block design. Ninety teeth were tested. Three different CAD/CAM ceramic onlay material types were included: a lithium disilicate glass-ceramic (IPS-e max CAD), a nano-filled resin-composite (Lava Ultimate), and a feldspathic porcelain (CEREC Blocs C).Three different preparation designs were included: an anatomical occlusal onlay preparation, a concave occlusal onlay preparation, and a flat occlusal onlay preparation. Two different tooth substrates were used: all in enamel, or in dentin with enamel peripheries. All teeth were restored and artificially aged. A load-to-failure test was used to measure the resistance to catastrophic fracture.Three-way ANOVA determined that of all the simple main effects, and all of their possible interactions, the only significant effect on failure load was that of material type (p < 0.0001). The glass-ceramic and resin-composite materials were stronger than the feldspathic porcelain. Multiple range analysis determined that restorations fabricated from feldspathic porcelain were significantly weaker than those made of glass-ceramic or resin-composite materials. The restorations in all 90 specimens fractured catastrophically; but only 26 of the 90 teeth fractured. Material type influenced the incidence of tooth fracture (Chi-square = 12, p < 0.05). Preparation design influenced the incidence of tooth fracture (Chi-square = 7, p < 0.05). Tooth substrate type did not influence the incidence of tooth fracture (Chi-square = 2, p > 0.05). A glass-ceramic restoration, and a concave preparation design were associated with increased incidences of tooth

Mammal teeth commonly possess a crown shape that is unique to each species, and, as a result, taxonomic identification of mammals relies heavily upon dental analysis. Ever-growing (hypselodont) cheek teeth, acquired convergently within numerous lineages of Cenozoic (66 Ma – present) mammals, retard wear associated with abrasive diets. Four major groups of notoungulates, a diverse group of extinct South American herbivorous mammals that flourished during the Cenozoic, acquired hypselodont cheek teeth. Simplification of crown morphology is a developmental consequence of hypselodonty, leaving tooth crown outline as a potential metric for taxonomic identification. One concern with this approach is that crown outline is prone to change, however, the inclusion of all possible crown outlines along the height of each tooth may effectively capture intraspecific variability. This study tests the power of crown outline shape analysis to discriminate among notoungulate genera/species. Micro-computed tomography, a non-destructive technique to visualize the internal structure of materials, was used to scan eight notoungulate specimens from five genera. From those eight specimens, 18 molars were reconstructed and analyzed. Teeth were sectioned digitally to ascertain how tooth outline would have changed during wear. Sections parallel to the occlusal surface for each tooth were subjected to elliptic Fourier analysis (EFA) to compare outline shape. Examination of the set of outlines from each tooth reveals that ontogenetic variation of crown outline along the height of a tooth is less than intraspecific variation, indicating that tooth crown outline can reliably discriminate among notoungulate groups.

The material of Rotundomys (Rodentia, Cricetinae) from the Late Miocene fossiliferous complex of Cerro de los Batallones (Madrid, Spain) is described and compared with all species currently placed in the genera Rotundomys and Cricetulodon. Both the morphology and size variation encompassed in the collection of specimens from Batallones suggest they belong to a single taxon different from the other known species of these genera. A new species Rotundomys intimus sp. nov. is, therefore, named for it. A cladistic analysis, which is the first ever published concernig these taxa, has been conducted to clear up the phylogenetic position of the new species. Our results suggest that Rotundomys intimus sp. nov. inserts between R. mundi and R. sabatieri as a relatively primitive taxon inside the clade Rotundomys. The new taxon is more derived than R. mundi in having a transversal connection between the metalophulid and the anterolophulid on some m1 but more primitive than R. sabatieri and the most evolved species of Rotundomys (R. montisrotuni +R.bressanus) in its less developed lophodonty showing distinct cusps, shallower valleys, and the presence of a subdivided anteroloph on the M1. The species of Cricetulodon do not form a monophyletic group. As a member of Rotundomys, Rotundomys intimus sp. nov. is more derived than all of these taxa in its greater lophodonty and the complete loss of the anterior protolophule, mesolophs, and mesolophids.

Introduction. Teeth hypomineralization that involves molars only, or molars and incisors is known as disease Molar Incisor Hypomineralization (MIH). Aetiology of MIH is not known, however, factors responsible for this disease are present in the first year of life. The aim of this research was to identify possible aetiological factors responsible for the occurrence of this disease. Material and Methods. The study included eight years old children from the municipality of Foca. Parents who gave their consent for the participation of children in the study completed a questionnaire in which they listed aetiological factors described in the literature to be responsible for the emergence of hypomineralization. Modified DDE index (Modified DDE Index for Use in Epidemiological Surveys) was used to estimate hypomineralization on all teeth; however, MIH changes were classified separately. Results. More than ninety different factors may be responsible for enamel defects. Possible aetiological factors listed in the literature are: premature birth, low weight of newborns, hypoxia, metabolic disorder of calcium and phosphate, fever, genetic factors, etc. Results did not confirm statistical significance for any of examined aetiological factors. Conclusion. In this study a retrospective analysis of data was performed. Etiological factors of MIH were identified but the most responsible for MIH were not determined., Uvod. Hipomineralizacija zuba koja zahvata samo kutnjake ili kutnjake i sekutiće istovremeno je oboljenje koje se u anglosaksonskoj literaturi naziva molar incisor hypomineralisation (MIH). Etiologija MIH promena još nije dovoljno poznata, ali se zna da faktori odgovorni za ovo oboljenje deluju kod deteta u prvoj godini po rođenju. Cilj rada je bio da se ustanove mogući etiološki faktori koji su odgovorni za nastanak hipomineralizacije zuba na sekutićima i kutnjacima dece u regionu opštine Foča, u Republici Srpskoj. Materijal i metode rada. U istraživanje su uključena osmogodišnja deca koja žive na teritoriji opštine Foča. Roditelji dece su dali pristanak za njihovo učešće u istraživanju i popunili anketni upitnik gde su navedeni etiološki faktori koji su, prema podacima iz literature, odgovorni za nastanak hipomineralizovanih promena. Za procenu hipomineralizacije na svim zubima korišćen je modifikovani DDE indeks (Modified DDE Index for Use in Epidemiological Surveys), ali su MIH promene i posebno klasifikovane. Rezultati. Više od 90 različitih faktora može biti odgovorno za oštećenje gleđi. Kao mogući etiološki faktori u literaturi se navode: prevremeno rođenje deteta, mala telesna težina novorođenčadi, hipoksija, poremećaj metabolizma kalcijuma i fosfata, visoka temperatura, uticaj genetskih faktora itd. U ovoj studiji nije potvrđena statistička značajnost ni za jedan ispitivani etiološki faktor. Zaključak. U ovom istraživanju nalazi su dobijeni na osnovu retrospektivne analize podataka. Ustanovljeni su brojni etiološki faktori, ali je bilo teško izdvojiti najodgovornije za nastanak MIH.

Murine rodents represent a highly diverse group, which displays great ecological versatility. In the present paper we analyse the relationship between dental morphology, on one hand, using geometric morphometrics based upon the outline of first upper molar and the dietary preference of extant murine genera, on the other. This ecomorphological study of extant murine rodents demonstrates that dietary groups can be distinguished with the use of a quantitative geometric morphometric approach based on first upper molar outline. A discriminant analysis of the geometric morphometric variables of the first upper molars enables us to infer the dietary preferences of extinct murine genera from the Iberian Peninsula. Most of the extinct genera were omnivore; only Stephanomys showed a pattern of dental morphology alike that of the herbivore genera.

Se estudió el patrón de mortandad del roedor Democricetodon larteti en el yacimiento de Somosaguas Sur (Mioceno medio) en función del grado de desgaste de sus terceros molares. Los resultados indican una gran abundancia de elementos muy poco desgastados (individuos juveniles) dentro de la población de estudio. Estos resultados no se ajustan a los patrones obtenidos en otros trabajos con poblaciones de roedores actuales ni con otros yacimientos. En cambio, se muestran claramente coherentes con los datos obtenidos para los macromamíferos de Somosaguas donde también existe una elevada mortandad de individuos juveniles asociada a eventos de gran aridez. [ABSTRACT] We studied the pattern of the age of death for Democricetodon larteti, a rodent species from the Somosaguas South fossil site (middle Miocene), in terms of wear degree of its third molars. The results indicate a great abundance of elements with scarce tooth wear (young individuals) in our study population. These results do not fi t in the pattern obtained in other works with modern rodents, or in other fossil sites. However, they are manifestly consistent with the data obtained in previous works with macromammals from Somosaguas, where the existence of high rate of death of young individuals is associated to events of high aridity., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

[ES] Se estudió el patrón de mortandad del roedor Democricetodon larteti en el yacimiento de Somosaguas Sur (Mioceno medio) en función del grado de desgaste de sus terceros molares. Los resultados indican una gran abundancia de elementos muy poco desgastados (individuos juveniles) dentro de la población de estudio. Estos resultados no se ajustan a los patrones obtenidos en otros trabajos con poblaciones de roedores actuales ni con otros yacimientos. En cambio, se muestran claramente coherentes con los datos obtenidos para los macromamíferos de Somosaguas donde también existe una elevada mortandad de individuos juveniles asociada a eventos de gran aridez., [EN] We studied the pattern of the age of death for Democricetodon larteti, a rodent species from the Somosaguas South fossil site (middle Miocene), in terms of wear degree of its third molars. The results indicate a great abundance of elements with scarce tooth wear (young individuals) in our study population. These results do not fi t in the pattern obtained in other works with modern rodents, or in other fossil sites. However, they are manifestly consistent with the data obtained in previous works with macromammals from Somosaguas, where the existence of high rate of death of young individuals is associated to events of high aridity.

A relief model on a purple rectangular background, consisting of three parts: an enlarged molar shown in cross section; a lateral view of the jaw, showing partial dentition; and a superior view of the jaw, showing complete dentition. Includes numbering on parts of the teeth for identification., Digestive System; Skeletal System, This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about

The purpose of this study was to determine the personal utility of asymptomatic third molar removal in military patients. From 1 to 30 days (mean=7.4) after the extraction of one or more third molars, 100 returning patients (all male, mean age=20.1) were asked to respond to hypothetical questions concerning the extraction of asymptomatic third molars. The results indicate general acceptance of the strategy of prophylactic third molar removal among a sample of military patients who have undergone pre-treatment counseling and the surgical procedure. A question remains as to the personal utility that might be measured prior to surgery.

The effect of root planing and curettage on the crevicular depth and periodontal attachment at the distal of mandibular second molars following removal of adjacent impacted or partially erupted third molars was evaluated in eighteen patients between the ages of eighteen and twenty-five presenting with bilateral similar impactions. No significant difference was demonstrated in the crevicular depths and attachment levels between the curetted, root planed side and the untreated controls. Thus, any benefits derived by root planing and curettage of mandibular second molars immediately following removal of adjacent impacted third molars are minimal. The best means of preserving periodontal attachment on mandibular second molars may be the removal of third molars at an early stage of tooth development. (Author)

An 8-piece color model of 6 human teeth in a gum line. Includes one-half incisor and root, one-half incisor and root, cuspid with amalgam filling, first biscuspid with decay and abscess, second bicuspid with gold bridge, replacement tooth with gold crown, second molar with gold bridge and gum line., Digestive System; Skeletal System, This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about

Five white plastic models of human molar teeth., Digestive System; Skeletal System, This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about

An 8-piece color model of 6 human teeth in a gum line. Includes one-half incisor and root, one-half incisor and root, cuspid with amalgam filling, first biscuspid with decay and abscess, second bicuspid with gold bridge, replacement tooth with gold crown, second molar with gold bridge and gum line., Digestive System; Skeletal System, This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about

A 10-piece model of 5 human teeth. Includes incisors, cuspids and molars., Digestive System; Skeletal System, This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about