Search

The objective of this study is to assess, using cone-beam CT (CBCT) examinations, the correlation between hard and soft anatomical parameters and their impact on the characteristics of the upper airway using symbolic regression as a machine learning strategy. Methods: On each CBCT, the upper airway was segmented, and 24 anatomical landmarks were positioned to obtain six angles and 19 distances. Some anatomical landmarks were related to soft tissues and others were related to hard tissues. To explore which variables were the most influential to explain the morphology of the upper airway, principal component and symbolic regression analyses were conducted. Results: In total, 60 CBCT were analyzed from subjects with a mean age of 39.5 ± 13.5 years. The intra-observer reproducibility for each variable was between good and excellent. The horizontal soft palate measure mostly contributed to the reduction of the airway volume and minimal section area with a variable importance of around 50%. The tongue and the position of the hyoid bone were also linked to the upper airway morphology. For hard anatomical structures, the anteroposterior position of the mandible and the maxilla had some influence. Conclusions: Although the volume of the airway is not accessible on all CBCT scans performed by dental practitioners, this study demonstrates that a small number of anatomical elements may be markers of the reduction of the upper airway with, potentially, an increased risk of obstructive sleep apnea. This could help the dentist refer the patient to a suitable physician.

Celiac disease (CD) is an immune-mediated systemic disorder caused by ingestion of the gluten found in wheat, rye, and barley. The currently estimated prevalence in children is about 1%. CD is a chronic enteropathy with gastrointestinal manifestations including diarrhea, abdominal distension and weight loss, but extra-intestinal features are increasingly being reported. Dental and oral manifestations such as dental enamel defects (ED), delay in dental eruption, and recurrent aphthous stomatitis (RAS) are well-recognized manifestations of CD. The aim of this study was to compare the frequency of oral manifestations (ED, RAS and delay in dental eruption) on deciduous and permanent teeth between children with CD and a control population. An oral examination was performed on 28 CD children and 59 control children. All children were younger than 12 years old and had deciduous or mixed dentition. CD children had significantly more ED and RAS than the control group (67.9% vs. 33.9% P=0.004 and 50.0% vs. 21.8% P=0.011, respectively). No delay in dental eruption was observed in CD children. ED were mainly grade I and II of Aine's classification (color defects and slight structural defects). ED were more often seen on CD children's deciduous teeth than on permanent teeth (57.1% and 13.6%, respectively; P0.001). The main teeth affected by ED are the second molar and canines of the deciduous teeth, and the first molar, central incisor, and lateral incisors of the permanent teeth. RAS and ED that were symmetrical in all quadrants and occurred firstly in teeth that mineralize during the first year of life both seem to be signs of CD. Thus, more information for dentists and pediatricians on these oral manifestations should help improve detection of CD.

A 12-year-old girl presented to the Department of Paediatric Dentistry of the Toulouse University Hospital 10 days after a facial injury, complaining of persistent pain and halitosis. Previous examinations only reported trauma of the upper incisors. Further clinical exploration showed an 8 cm laceration of the oral mucosa in the lower labial sulcus, 1.5 cm inferior to the gingival margin and exposing the symphyseal bone. The diagnosis of mental protuberance degloving was established. The treatment consisted of debridement of the wound, removal of the necrotic tissue, multiple plane sutures and antibiotics. Complete healing of the wound with no sensory deficit was achieved. Mental degloving injuries occur when a shearing force is applied to the soft tissues overlying the chin, stripping them from the labial bone. This type of wound is rare and can go undetected if a meticulous oral examination is not performed. Early management is essential so healing is not compromised.

Objectives The location of the mandibular foramen is essential for the quality of the inferior alveolar nerve block anaesthesia and has often been studied with contradictory results over the years. The aim of this study was to locate the mandibular foramen, according to the dental age of the subject, through 3D analysis. Methods Three-dimensional images were reconstructed from mandibular computed tomography of 260 children, adolescents and adults. The occlusal plane was determined as the average plane passing through the buccal cusps of mandibular molars, premolars, and canines, and through the incisor edge. The mandibular foramen was located three dimensionally in relation to the anterior edge of the ramus (or coronoid notch), the sagittal plane and the occlusal plane. Results All along mandibular growth, the three distances defining the relative position of the mandibular foramen showed negligible changes. The mandibular foramen is located from − 0.4 to 2.9 mm above the occlusal plane. The distance between the mandibular foramen and the leading edge of the mandibular ramus ranged from 17 to 19.5 mm. The angle between the ramus and the sagittal plane ranged from 3° to 5.4°. Conclusion In our sample, and using the occlusal plane and the anterior edge of the ramus as anatomical references, the location of the mandibular foramen was considered to be similar in all patients regardless of age.

Objective. The aim of this study was to perform an analysis of angular measurements (from both the full face and profile), according to shapes of the human face. Method. It was a descriptive and cross-sectional study of 108 black Ivorian subjects. For each subject selected, two standardized photographs (full face and profile) were taken, followed by anthropometric measurements. The data collected were analyzed using the SPSS 20.0 statistics software for Windows. Results. In the present work, the faces were considered according to three particular qualifiers: broad face, medium face, and narrow face. Thus, 45.37% of the faces in this study were large, 31.48% on average, and 23.15% narrow. The interlabial angles of average face and long face were wider than that of large face with p<0.01. The angle of the facial width was higher for large face and average face, compared to narrow face (p<0.001). Conclusion. Median and bilateral angles lead to rational understanding of the various shapes of the human face.

The aim of this national survey was to record the use of nitrous oxide and the perceptions of French dental practitioners to this form of sedation. The use of nitrous oxide sedation (NOS) has been authorised in private dental practice in France since December 2009 but, to date, no study implementing both quantitative and qualitative methods has explored such use. The data were collected using a Google Forms questionnaire. A mixed methodology was used for data analysis: a quantitative approach to explore the use of conscious sedation and a qualitative thematic approach (using Nvivo software) to determine the practitioner’s perception of it. Responses were collected from 225 practitioners (19% of the target population of 1185). Most of the responders were trained in NOS use in private dental clinics. Seventy-three percent of those who trained privately actually used NOS, compared to 53% of those trained at university (p-value = 0.0052). Above all, NOS was used for children requiring restorative dentistry. The average price of the sedation was 50 Euros and it lasted, on average, for 37 min. The qualitative and thematic analysis revealed the financial and technical difficulties of implementing NOS in private practice. However, it also showed the benefits and pleasure associated with NOS use. This statistical survey of French dental practitioners offers an insight of the current state of the use of conscious sedation with nitrous oxide in private general dental practice in France. It also includes the first report of dental practitioners’ perceptions of NOS use and may lead to a better understanding of the reasons why sedation is sometimes not used in private practice.

Contexte : L’evaluation clinique des etudiants en chirurgie-dentaire est traditionnellement basee sur des criteres quantitatifs, correspondant a un nombre minimum d’actes specifiques a realiser. Ce type de methode est remis en question, en raison de l’environnement comptable qu’il induit aupres des etudiants, et de la deshumanisation de la relation de soins qui s’ensuit. But : Ce travail a pour objectif d’evaluer l’impact de la mise en place d’une evaluation alternative, de type « patient-traite », pour laquelle l’objet de l’evaluation est le patient et non plus seulement l’acte technique. Methodes : Il s’agit d’une etude unicentrique de type qualitatif, conduite a partir d’entretiens semi-diriges aupres d’etudiants en derniere annee d’etude de chirurgie dentaire, a la faculte de Toulouse durant l’annee 2015–2016. Les donnees sont recueillies jusqu’a saturation des themes et analysees selon la methode de l’analyse thematique. Resultats : Cette etude montre que l’evaluation quantitative est globalement acceptee par les etudiants et repond a certaines attentes sur le nombre d’actes realises. Elle confirme egalement les effets indesirables d’une evaluation clinique quantitative, comme les abandons de patients ou les modifications de plan de traitement. L’evaluation par patient-traite est percue comme plus humaine, moins stressante et plus efficace. Conclusion : Des methodes d’evaluation clinique nouvelles, mettant au centre du dispositif les etudiants et les patients, doivent etre developpees pour favoriser l’emergence de competences en phase avec les evolutions societales.

Resume Objectif L’objectif de cette etude d’evaluer les caracteristiques photogrammetriques angulaires suivant les criteres d’appreciation esthetique faciale des sujets ivoiriens. Materiel et methode Il s’agissait d’une etude transversale, ayant concerne un groupe de jeunes ivoiriens qui ont fait l’objet d’appreciation et de traces photogrammetriques. Les donnees recueillies ont ete analysees grâce au logiciel de statistique SPSS 20.0. La signification statistique est fixee a p 0,05. Une ACP a permis de caracteriser les sujets. Resultats Les sujets attrayants avaient l’etage ventilatoire important avec un nez retrousse ( p 0,01). Les femmes attrayantes avaient un profil facial plus convexe que les hommes juges beaux. Conclusion Malgre la subjectivite de la notion de beaute, certains angles du profil facial contribuent a l’equilibre esthetique du visage du sujet melano-ivoirien.

Summary Aim The aim of this study was to evaluate the angular photogrammetric characteristics of subjects according to the facial esthetics criteria applicable in Cote d’Ivoire. Material and methods This was a horizontal study, concerning of group of young people from Cote d’Ivoire whose attractiveness and photogrammetric characteristics were assessed. The data obtained were analyzed using SPSS 20.0 statistical software. The limit of statistical significance was P 0.05. Subjects were characterized by PCA. Results Attractive subjects had a large mid-face section with an upturned nose ( P 0.01 ). Attractive women had facial profiles that were more convex than men who were judged handsome. Conclusion Despite the subjectivity of the notion of beauty, certain angles of the facial profile contribute to the esthetic balance of black Ivorian faces.

Photobiomodulation is recommended in adults for the prevention of mucositis induced by cervicofacial irradiation or pre-transplant chemotherapy. The results of pediatric studies are promising but this support treatment is still underused. The objective was to conduct a feasibility study in the pediatric hematology-oncology unit at X Children's Hospital. Extra- and intraoral scans were performed a minimum of three times every 2 days for grade 2 or higher mucositis in children (median age, 8.6 years) using the Oncolase laser (Biophoton, Saint Alban, France), with a combination of two wavelengths (635 and 815nm). The effect of the laser on mucositis grade, pain, the child's tolerance, and the time dedicated to this care were also evaluated. The success of the procedure was 77% in 1 year, with the inclusion of 84% of the patients (n=22) and 146 laser treatment sessions (median of four per episode of mucositis). We observed excellent tolerance and pain relief with a gain of two points on the VAS and the HEDEN mucositis scale. This study shows that photobiomodulation that incorporates two application modes (intra- and extraoral) through the combination of two wavelengths is feasible when integrated into the care of a pediatric hematology-oncology department and is perfectly tolerated, even by young children. Along with oral hygiene and analgesic management, it alleviates pain associated with oral mucositis.

Objectives: The scoring and analysis of dental nonmetric traits are predominantly accomplished by using the Arizona State University Dental Anthropology System (ASUDAS), a standard protocol based on strict definitions and three‐dimensional dental plaques. However, visual scoring, even when controlled by strict definitions of features, visual reference, and the experience of the observer, includes an unavoidable part of subjectivity. In this methodological contribution, we propose a new quantitative geometric morphometric approach to quickly and efficiently assess the variation of shoveling in modern human maxillary central incisors (UI1).\ud \ud Materials and methods: We analyzed 87 modern human UI1s by means of virtual imaging and the ASU‐UI1 dental plaque grades using geometric morphometrics by placing semilandmarks on the labial crown aspect. The modern human sample was composed of individuals from Europe, Africa, and Asia and included representatives of all seven grades defined by the ASUDAS method.\ud \ud Results: Our results highlighted some limitations in the use of the current UI1 ASUDAS plaque, indicating that it did not necessarily represent an objective gradient of expression of a nonmetric tooth feature. Rating of shoveling tended to be more prone to intra‐ and interobserver bias for the highest grades. In addition, our analyses suggest that the observers were strongly influenced by the depth of the lingual crown aspect when assessing the shoveling.\ud \ud Discussion: In this context, our results provide a reliable and reproducible framework reinforced by statistical results supporting the fact that open scale numerical measurements can complement the ASUDAS method.

Necrotizing ulcerative gingivitis, sometimes observed in young children, may lead to necrotizing stomatitis and noma. Therefore, its interception is a necessity and a challenge for the paediatric practitioners. First, this article aims to propose a systematic review of recent literature on the use of local antiseptic and antibiotic prescription in this particular periodontal condition. Then, a protocol is proposed to have a simple, costless and reproducible treatment on children.

Introduction Dental education emphasises the acquisition of technical skills. Recent advances in 3D printing technologies have enabled the emergence of new educational tools usable in hands-on work sessions. The possibility to print 3D models from CT scans of patients is now available to dental practitioners. The aim of this study was to develop and evaluate a 3D printed model for paediatric dentistry training and compare it to the reference model used in our faculty. Materials and method 3D models were obtained by modifying and printing the CT scan of a young patient using the Voco® Solflex 350 3D® printer and Voco® V-print resin. Thirty-four students were asked to perform a pulpotomy and preparation for a stainless steel paediatric crown on tooth 85 on both the 3D printed model and the industrial model (Frasaco®), and then to answer a questionnaire. The data were analysed using R software. Result Both models obtained high scores. The learning potential and its applicability to clinical practice showed no statistically significant difference. Although the colour and the simulation of the proximal area disturbed the students (P = 0.009), the 3D models were seen as a good idea (P = 0.012). When it came to model design, the students appreciated the simulation of caries on 3D models (P = 0.0001) and considered the use 3D of models as a more realistic experience (P = 0.017). Discussion Although this study has some limitations (number of participants, choice of the models to be compared), it constitutes the first attempt to compare students' perception of 3D and series models. It shows that 3D technology makes it possible to obtain models of similar quality while offering a more realistic experience. Conclusion There are still many ways in which these models could be improved. For example, modifying the quality of resins could improve the milling sensation, and the design could be improved to achieve better contact points. Nevertheless, these 3D models offer the possibility to give the patient a more central place in the education of future practitioners.

Proteus syndrome (PS) is a sporadic and rare congenital disorder characterized by a patchy or mosaic postnatal overgrowth, sometimes involving the face. The onset of overgrowth typically occurs in infancy and can commonly involve skin, connective tissue, central nervous system, eyes and viscera. The progressive overgrowth causes severe complications, such as skeletal deformities, cystic lung disease, invasive lipomas, connective tissue hyperplasia, benign and malignant tumours and deep venous thrombosis with pulmonary embolism, which can cause premature death. This disorder is caused by somatic mosaicism for a specific activating AKT1 mutation that would be lethal in a non-mosaic state. In this report, current knowledge of the aetiology, the diagnosis and the craniofacial manifestations of the disorder are reviewed. The short-term management of a 7-year-old patient with unusual oral manifestations is described. For the first time mutation of AKT1 (c.49G > A) gene was detected both in cranial exostosis and in central odontogenic fibroma of the lower jaw.

The subarcuate fossa, or petromastoid canal, is a hypostotic feature of the temporal bone used for assessing the age at death of immature individuals. The present study uses the high-resolution micro-CT record of 20 extant human infant and juvenile temporal bones to more precisely assess the age-related maturational pattern of this bony structure. In the perspective of the application of our analytical protocol to the study of the hominid fossil record, the main goals of this contribution are to extend the amount and to improve the quality of the linear and volumetric information on the human subarcuate fossa by the application of new 3D imaging techniques.

Keratocysts, also known as keratocystic odontogenic tumors (KCOT), make up 7% of all odontogenic cysts and develop asymptomatically in most cases. Enucleation is the benchmark treatment. However, there are surgical alternatives. Marsupialization and decompression are necessary in some cases, mainly when the KCOT is large, thus causing an increased risk of bone fracture, or if it has engulfed important elements such as the inferior alveolar nerve or teeth, consequently causing alveolar bone growth failure. The authors describe the case of a nine-year-old child treated for a large keratocyst situated in sector 4 (lower right jaw), impacting both premolars and the canine (45, 44 and 43). Surgical decompression associated with orthodontic multiband treatment were delivered to pull, and then place the three teeth in occlusion on the dental arch. With seven years hindsight since the first surgical procedure and three years since finishing orthodontic treatment, the cooperation between orthodontists and surgeons can be considered a success, from both the functional and esthetic points of view.

Acute leukaemia is the most common type of childhood cancer, the acute lymphoblastic type accounting for the majority of cases. Children affected by leukaemia receive various forms of treatments including chemotherapeutic agents and stem cell transplants. Leukaemia and its treatment can directly or indirectly affect oral health and further dental treatments. The oral complications include mucositis, opportunistic infections, gingival inflammation and bleeding, xerostomia and carious lesions. An additional consideration in children is the impact of the treatments on the developing dentition and on orofacial growth. The aim of this review is to describe the oral complications in children with acute lymphoblastic leukaemia and the methods of prevention and management before, during and after the cancer treatment.

SUMMARYThe pathogenicity of Trichomonas species is well documented. Although their exact involvement in gum disease is not fully understood, recent studies suggest a correlation between these protozoa and periodontitis. This case report details the first chair-side observation in Europe of an oral trichomonad infection in a child with periodontitis, by direct microscopy. The dramatic recovery of the patient, observed following administration of an anti-parasitic treatment, confirms the necessity of further investigation in this field.

Ectodermal dysplasias (ED) are a clinically and genetically heterogeneous group of hereditary disorders that have in common abnormal development of ectodermal derivatives. Hypohidrotic ectodermal dysplasia (HED) is characterized by abnormal development of eccrine sweat glands, hair, and teeth. The X-linked form of the disease, caused by mutations in the EDA gene, represents the majority of patients with the hypohidrotic form. Autosomal dominant and autosomal recessive forms are occasionally seen, and result from mutations in at least three genes (WNT10A, EDAR, or more rarely EDARADD). We have screened for mutations in EDAR (commonly involved in the hypohidrotic form) and WNT10A (involved in a wide spectrum of ED and in isolated hypodontia) in a cohort of 36 patients referred for EDA molecular screening, which failed to identify any mutation. We identified eight EDAR mutations in five patients (two with homozygous mutations, one with compound heterozygous mutations, and two with heterozygous mutation), four of which were novel variants. We identified 28 WNT10A mutations in 16 patients (5 with homozygous mutations, 7 with compound heterozygous mutations, and 4 with heterozygous mutations), seven of which were novel variants. Our study allows a more precise definition of the phenotypic spectrum associated with EDAR and WNT10A mutations and underlines the importance of the implication of WNT10A among patients with ED. © 2013 Wiley Periodicals, Inc.

Objective: The aim of this study was to evaluate the attitude of parents towards the oral health of their children before oral rehabilitation under general anesthesia (GA).Study design: Children receiving dental treatment under GA between November 2013 and July 2014 in the Pediatric Dentistry Department (University Hospital Center, Toulouse, France) were enrolled in an oral health preventive program. An anonymous questionnaire was self-administered by the parents during the pre-operative session. Results: The sample comprised 67 children with a mean age of 4.8 years. 48 % of the parents had difficulties in maintaining the oral hygiene of their child. Two thirds of them reported a lack of cooperation. An adult cleaned the child's teeth in 43% of the cases. 14% of the study population brushed their teeth twice a day or more. In addition, half of the parents reported that they modified food consumption or teeth cleaning habits of their children since the initial consultation. Conclusions: This study suggests a low compliance of parents and children with the recommendations on oral hygiene and food consumption given at the initial visit and demonstrates the feasibility of a preventive program in this population.

Periodontitis is a chronic-, infectious-disease of the human periodontium that is characterized by the loss of supporting tissues surrounding the tooth such as the periodontal ligament (PDL), cementum and alveolar bone. Regeneration of the periodontium is dependent on the participation of mesenchymal stem/stromal cells (MSC) resident in the PDL. Enamel matrix derivative (EMD), an extract from immature porcine enamel rich in amelogenin protein but that also contain bone morphogenetic protein (BMP), is used to treat periodontal defects. The effects of EMD on MSC cells of the PDL are not well characterized. In this in vitro study, we identify PDL progenitor cells from multiple individuals and demonstrate that EMD stimulates them. We show that the effect of EMD on cell proliferation and migration is mediated through the amelogenin it contains, while the differentiation of these progenitor cells to cell types of mineralized tissue is mainly due to BMP signaling.

Polyvalvular heart disease has been reported in a handful of "private" syndromes that have been recently suggested to represent a single dominantly inherited condition, the polyvalvular heart disease syndrome. We report five cases in two unrelated families (one sporadic case in the first family and three siblings and their father in the second family) with the same association of polyvalvular heart disease, distinctive facial appearance, and, except the father in family 2, major joint hypermobility. Interestingly, in three of our patients (2 siblings and the sporadic case), electron microscopy revealed characteristic ultrastructural skin abnormalities with abnormal amorphous or microfibrillar deposits under the capillary basal membrane in the papillary dermis, suggestive of a connective tissue disorder, but different from Marfan syndrome or Ehlers-Danlos syndrome. Moreover, in family 2, three others sibs died in early infancy of their heart defect. Our two families and the other published cases might illustrate intrafamilial and interfamilial variability within a single condition. However, our two families disclose major joint hypermobility, normal stature, and ultrastructural skin abnormalities that were not described in the previous reports. These discrepancies let us to consider them as affected by a distinct disorder of the connective tissue.

International audience

Oral candidiasis is one of the most common opportunistic fungal infections of the oral cavity in human. Among children, this condition represents one of the most frequent affecting the mucosa. Although most diagnoses are made based on clinical signs and features, a microbiological analysis is sometimes necessary. We performed a literature review on the diagnosis of oral candidiasis to identify the techniques most commonly employed in routine clinical practice.A Medline-PubMed search covering the last 10 years was performed.Microbiological techniques were used in cases requiring confirmation of the clinical diagnosis. In such cases, direct microscopy was the method most commonly used for diagnosing candidiasis.Direct microscopy appears as the method of choice for confirming clinical diagnosis and could become a routine chair-side technique.

La prevention des lesions carieuses initiales chez l'enfant et plus particulierement lors des traitements orthodontiques repose sur l'instauration et le suivi, des le plus jeune âge, de l'hygiene bucco-dentaire, sur la fluoration systemique et topique.Les phenomenes de de-remineralisation de l'email sont complexes.La fluoration systemique garde tout son interet, mais elle ne doit etre instauree qu'apres un bilan fluore pour ecarter tout risque de fluorose. La fluoration topique reste fondamentale, pourvu que le praticien soit vigilant et suscite une cooperation entiere du jeune patient, assortie d'une surveillance bucco-dentaire reguliere.

Une patiente âgee de 7 ans consulte pour un bilan bucco-dentaire au cours duquel de nombreuses anomalies sont relevees : hypotaurodontisme, calcifications intrapulpaires, cicatrices cutanees anormales… L’anamnese evoque une cicatrisation de mauvaise qualite apres blessures et des luxations articulaires recidivantes (epaule droite, notamment). Devant ce tableau clinique, des investigations complementaires sont menees au CHU de Toulouse, dans le service de pediatrie, qui amenent a poser le diagnostic de syndrome d’Ehlers-Danlos (SED). Cette pathologie du collagene s’accompagne de signes generaux typiques, parfois discrets, mais aussi de symptomes bucco-dentaires qui peuvent constituer des signes d’appel.L’objectif de cet article est de presenter les principaux symptomes mais egalement de definir quelques principes pour la prise en charge de ces patients par l’odontologiste.

Hypophosphatasia is an inheritable disorder characterised by defective bone mineralisation due to the impaired activity of tissue-non-specific alkaline phosphatase (AP). Clinical presentation ranges from stillbirth without mineralised bone to pathological fractures in late adulthood. During childhood, the main manifestations include rickets, growth delay and dental problems. Fractures and bone pain usually characterise the adult form. A 9-year-old girl was referred for repetitive fractures after minimal trauma. She had normal growth, normal sclerae, no rickets and minimal dental abnormalities. Her sister had also presented fractures. The proband, her sister and mother had low total and bone-specific AP levels and E435K mutation in exon 12 of the liver/bone/kidney AP gene. Low AP levels must lead to genetic analysis. Bone fragility and repetitive fractures may be symptoms of hypophosphatasia in childhood, which must not be neglected. Associated factors such as vitamin D or calcium deficiency must be prevented. In conclusion, hypophosphatasia must not be forgotten as an aetiological factor of repetitive fractures or bone pain in children and AP activity should be checked accurately.

The shoveling of the maxillary central incisor is a non-metric dental characteristic frequently used in anthropology as an indicator of population relations for its taxonomic and phylogenetic relevance for many decades. This dental morphological feature is defined as the degree of elevation of the mesial and distal marginal ridges on the lingual surface of the maxillary incisors, canines and mandibular incisors, with more pronounced pit-like forms. From the 19th century until today, several attempts have been made to classify and assess the shoveling differences between fossil and modern human populations, first using detailed descriptive approaches and later developing ordinal feature notation systems. The standard gold technique for shoveling analysis is based on a seven-grade ordinal scale that has been adapted and integrated into a formal system for scoring non-metric features of dental morphology: the Arizona State University Dental Anthropology System (ASUDAS). This widely-used standard protocol is based on reference plaster plaques representing the casts of selected teeth showing a gradient of expression of a particular trait. Ordinal notation, even if controlled by strict definitions of characteristics, visual references, and observer experience, includes an inevitable element of subjectivity. Moreover, the conventional information support used by ASUDAS can lead to loss of information over time. Some researchers have attempted to reduce visual subjectivity by measuring the depth of lingual shoveling, but with little success in their results due to method accuracy problems. First, we developed a new quantitative morphometric approach to assess the shoveling variation of modern human maxillary central incisors (UI1). We analyzed by virtual imaging 87 modern human UI1 (Europe, Africa, Asia) and the 7 UI1 of the ASU-UI1 reference plaque using geometric morphometry and the positioning of sliding reference points. The results of the distribution of shoveling according to populations according to our new morphometric method are in close correlation with the distribution of shoveling widely described in the literature. In addition, our results showed some limitations in the use of ASUDAS plaques, suggesting that they do not necessarily represent an objective gradient of expression of this non-metric dental characteristic. [...]; Le shoveling de l'incisive centrale maxillaire est une caractéristique dentaire non-métrique utilisée en anthropologie comme indicateur des relations entre les populations. Ce trait morphologique dentaire est défini comme le degré d'élévation des crêtes mésiales et distales marginales sur la surface linguale des incisives maxillaires avec des formes plus prononcées renfermant une fosse. Plusieurs tentatives ont été faites pour classer et évaluer les différences de shoveling entre les populations humaines modernes et fossiles, en utilisant d'abord des approches descriptives détaillées et en élaborant par la suite des systèmes de notation ordinale des traits. A ce jour, la technique gold standard pour l'analyse du shoveling est basée sur une échelle ordinale de sept grades qui a été adaptée et intégrée à un système formel de notation des traits non métriques de la morphologie dentaire: le Arizona State University Dental Anthropology System (ASUDAS). Ce protocole standard est basé sur des plaques de plâtre de référence représentant les moulages de dents sélectionnées montrant un gradient d'expression d'un trait particulier. La notation ordinale, même si elle est contrôlée par des définitions strictes des caractéristiques, des références visuelles et l'expérience de l'observateur, comprend une part inévitable de subjectivité. De plus, les supports d'information conventionnels utilisés par ASUDAS peuvent entrainer des pertes d'information dans le temps. Dans un premier temps, nous avons élaboré une nouvelle approche morphométrique quantitative pour évaluer la variation du shoveling des incisives centrales maxillaires humaines modernes (UI1). Nous avons analysé par imagerie virtuelle 87 UI1 humaines modernes (Europe, Afrique, Asie) et les 7 UI1 de la plaque de référence ASU-UI1 en utilisant la morphométrie géométrique et le positionnement de points de repères glissants. Les résultats de la répartition du shoveling en fonction des populations selon notre nouvelle méthode morphométrique sont en étroite corrélation avec la répartition du shoveling largement décrite dans la littérature. En outre, nos résultats ont mis en évidence certaines limites dans l'utilisation des plaques ASUDAS, laissant supposer qu'elles ne représentent pas nécessairement un gradient objectif d'expression de cette caractéristique dentaire non métrique. [...]

The shoveling of the maxillary central incisor is a non-metric dental characteristic frequently used in anthropology as an indicator of population relations for its taxonomic and phylogenetic relevance for many decades. This dental morphological feature is defined as the degree of elevation of the mesial and distal marginal ridges on the lingual surface of the maxillary incisors, canines and mandibular incisors, with more pronounced pit-like forms. From the 19th century until today, several attempts have been made to classify and assess the shoveling differences between fossil and modern human populations, first using detailed descriptive approaches and later developing ordinal feature notation systems. The standard gold technique for shoveling analysis is based on a seven-grade ordinal scale that has been adapted and integrated into a formal system for scoring non-metric features of dental morphology: the Arizona State University Dental Anthropology System (ASUDAS). This widely-used standard protocol is based on reference plaster plaques representing the casts of selected teeth showing a gradient of expression of a particular trait. Ordinal notation, even if controlled by strict definitions of characteristics, visual references, and observer experience, includes an inevitable element of subjectivity. Moreover, the conventional information support used by ASUDAS can lead to loss of information over time. Some researchers have attempted to reduce visual subjectivity by measuring the depth of lingual shoveling, but with little success in their results due to method accuracy problems. First, we developed a new quantitative morphometric approach to assess the shoveling variation of modern human maxillary central incisors (UI1). We analyzed by virtual imaging 87 modern human UI1 (Europe, Africa, Asia) and the 7 UI1 of the ASU-UI1 reference plaque using geometric morphometry and the positioning of sliding reference points. The results of the distribution of shoveling according to populations according to our new morphometric method are in close correlation with the distribution of shoveling widely described in the literature. In addition, our results showed some limitations in the use of ASUDAS plaques, suggesting that they do not necessarily represent an objective gradient of expression of this non-metric dental characteristic. [...]; Le shoveling de l'incisive centrale maxillaire est une caractéristique dentaire non-métrique utilisée en anthropologie comme indicateur des relations entre les populations. Ce trait morphologique dentaire est défini comme le degré d'élévation des crêtes mésiales et distales marginales sur la surface linguale des incisives maxillaires avec des formes plus prononcées renfermant une fosse. Plusieurs tentatives ont été faites pour classer et évaluer les différences de shoveling entre les populations humaines modernes et fossiles, en utilisant d'abord des approches descriptives détaillées et en élaborant par la suite des systèmes de notation ordinale des traits. A ce jour, la technique gold standard pour l'analyse du shoveling est basée sur une échelle ordinale de sept grades qui a été adaptée et intégrée à un système formel de notation des traits non métriques de la morphologie dentaire: le Arizona State University Dental Anthropology System (ASUDAS). Ce protocole standard est basé sur des plaques de plâtre de référence représentant les moulages de dents sélectionnées montrant un gradient d'expression d'un trait particulier. La notation ordinale, même si elle est contrôlée par des définitions strictes des caractéristiques, des références visuelles et l'expérience de l'observateur, comprend une part inévitable de subjectivité. De plus, les supports d'information conventionnels utilisés par ASUDAS peuvent entrainer des pertes d'information dans le temps. Dans un premier temps, nous avons élaboré une nouvelle approche morphométrique quantitative pour évaluer la variation du shoveling des incisives centrales maxillaires humaines modernes (UI1). Nous avons analysé par imagerie virtuelle 87 UI1 humaines modernes (Europe, Afrique, Asie) et les 7 UI1 de la plaque de référence ASU-UI1 en utilisant la morphométrie géométrique et le positionnement de points de repères glissants. Les résultats de la répartition du shoveling en fonction des populations selon notre nouvelle méthode morphométrique sont en étroite corrélation avec la répartition du shoveling largement décrite dans la littérature. En outre, nos résultats ont mis en évidence certaines limites dans l'utilisation des plaques ASUDAS, laissant supposer qu'elles ne représentent pas nécessairement un gradient objectif d'expression de cette caractéristique dentaire non métrique. [...]