The Ice Man's diet as reflected by the stable nitrogen and carbon isotopic composition of his hair.
(1/37)
Establishing the diets of ancient human populations is an integral component of most archaeological studies. Stable isotope analysis of well-preserved bone collagen is the most direct approach for a general assessment of paleodiet. However, this method has been limited by the scarcity of well-preserved skeletal materials for this type of destructive analysis. Hair is preserved in many burials, but is often overlooked as an alternative material for isotopic analysis. Here we report that the stable carbon and nitrogen isotope values for the hair of the 5200 year-old Ice Man indicates a primarily vegetarian diet, in agreement with his dental wear pattern. Whereas previous investigations have focused on bone collagen, the stable isotope composition of hair may prove to be a more reliable proxy for paleodiet reconstruction, particularly when skeletal remains are not well preserved and additional archaeological artifacts are unavailable. (+info)
Long-term follow-up of maxillary incisors with severe apical root resorption.
(2/37)
The purpose of the study was to analyse the mobility of teeth with severe orthodontically induced root resorption, at follow-up several years after active treatment, and to evaluate mobility in relation to root length and alveolar bone support. Seventy-three maxillary incisors were examined in 20 patients, 10-15 years after active treatment in 13 patients (age 24-32 years) and 5-10 years after active treatment in seven patients (age 20-25 years). All had worn fixed or removable retainers; seven still had bonded twistflex retainers. Total root length and intra-alveolar root length were measured on intra-oral radiographs. Tooth mobility was assessed clinically according to Miller's Index (0-4) and the Periotest method. Crestal alveolar bone level, periodontal pocket depth, gingival, and plaque indices, occlusal contacts during occlusion and function, and dental wear were recorded. There was a significant correlation (P < 0.05) between tooth mobility, and total root length and intra-alveolar root length. No correlation was found between tooth mobility and retention with twistflex retainers. None of the variables for assessment of periodontal status, occlusion and function were related to total root length or tooth mobility. It is concluded that there is a risk of tooth mobility in a maxillary incisor that undergoes severe root resorption during orthodontic treatment, if the remaining total root length is < or = 9 mm. The risk is less if the remaining root length is > 9 mm. Follow-up of teeth with severe orthodontically induced root resorption is indicated. (+info)
Consensus-based recommendations for the diagnosis and management of dentin hypersensitivity.
(3/37)
These consensus recommendations for the diagnosis and management of dentin hypersensitivity were developed by a broadly constituted board of dentists and dental hygienists drawn from general dental practice, specialist practice, academia and research from across Canada, joined by 2 international dentists with subject matter expertise. The need for consensus recommendations was made evident by the lack of clear and robust evidence in the dental literature, as well as confusion about diagnosis and management demonstrated by an educational needs assessment survey. High prevalence of the condition, underdiagnosis and widespread availability of noninvasive, efficacious and inexpensive preventive treatment further underscored the need for direction. This paper outlines the key elements of the scientific basis for the causes, diagnosis and management of dentin hypersensitivity; where such evidence is deficient, the document relies on the compound experience of the board. A simple algorithm was developed to guide clinicians through the diagnostic process and assist them in determining appropriate case management. Finally, the board makes a series of recommendations to raise awareness, to improve dental education, to develop symbols for charting, to develop an index for case assessment and for further research. (+info)
Rates of anterior tooth wear in Middle Pleistocene hominins from Sima de los Huesos (Sierra de Atapuerca, Spain).
(4/37)
This study presents quantitative data on the rates of anterior tooth wear in a Pleistocene human population. The data were obtained for the hominin sample of the Sima de los Huesos site in Atapuerca, Spain. The fossil record belongs to a minimum of 28 individuals of the same biological population, assigned to the species Homo heidelbergensis. We have estimated the original and the preserved crown height of the mandibular incisors (I1 and I2) of 11 individuals, whose age at death can be ascertained from the mineralization stage and tooth eruption. Results provide a range of 0.276-0.348 and 0.288-0.360 mm per year for the mean wear rate of the mandibular I1 and I2, respectively, in individuals approximately 16-18 years old. These data suggest that incisors' crowns would be totally worn out toward the fifth decade of life. Thus, we expect the life expectancy of this population to be seriously limited. These data, which could be contrasted with results obtained on hominins at other sites, could be of interest for estimating the death age of adult individuals. (+info)
Oral habits of temporomandibular disorder patients with malocclusion.
(5/37)
The purpose of this study was to clarify the relationship between oral habits and symptoms of temporomandibular joint disorder in patients who had sought orthodontic treatment by analyzing their present and past history. The subjects were 57 female patients (average age: 23 years and 6 months old) who had visited the "Temporomandibular Disorder Section" in our orthodontic department. Their chief complaints were the symptom of TMJ and the abnormalities of occlusion such as maxillary protrusion, open bite, crowding, mandibular protrusion, cross bite, deep bite, edge-to-edge bite, and spacing. Their present conditions and past histories were examined and evaluated. The most typical primary symptom was joint sound (23 patients, 40.0%). The second was joint sound and pain (15 patients, 26.3%). Of the symptoms present at the time of examination, the most prevalent were joint sound and pain (20 patients, 35.1%). The 48 patients (82.8%) had significant oral habits. Unilateral chewing was seen in 35 patients (72.9%), bruxism in 27 (56.3%), abnormality of posture in 14 (29.2%), habitual crunching in 10 (20.8%) and resting the check on the hand in 4 (8.3%), respectively. When comparing the primary symptoms to those at the time of examination, the patients with unilateral chewing and bruxism tended to have more complicated symptoms. In conclusion, the TMD symptoms of the patients with notable oral habits did not change or become worse during a period of about 5 years. (+info)
Dental crowding in a prehistoric population.
(6/37)
The aims of this study were to investigate dental crowding from the Copper Age and examine the extent and patterns of wear. Crowding was estimated in 43 adult mandibles using Little's irregularity index. Dental wear, dental diameters, arch width and the presence of third molars were also studied as possible aetiological factors for crowding. The remains were found at the archaeological site of Roaix, located in the south of France. Radiocarbon dating indicated that the lower layer was from 2150 +/- 140 years BC (date +/- 1 standard deviation) and the upper level from 2090 +/- 140 years. The graves were estimated to contain the remains of 150 adults and 50 children. Forty-three intact mandibles were used for this study. All of the mandibles presented incisor crowding with a majority of minimal and moderate irregularities, but in seven cases there were extreme irregularities and in two canine impaction was observed. These results are in contrast with the literature where it is reported that malocclusions were rare in prehistoric populations. The findings of this study suggest that crowding may be of a genetic origin and might not be caused by excessive tooth size or changes in environmental factors (masticatory activity). (+info)
Relationship between large tubules and dentin caries in human deciduous tooth.
(7/37)
The purpose of this study was to elucidate the relationship between large tubules and dentin caries by using human deciduous incisors that showed various levels of attrition but no macroscopical lesions resulting from caries. The teeth were cut longitudinally in the mesio-distal direction and the exposed surfaces observed with a high-resolution field emission scanning electron microscope. The inside of each large tubule showed dense collagen fibers running parallel to its long axis and small spherical bodies of aggregated crystals, but no marked attrition. In teeth where attrition had exposed dentin at the incisal edge, oral bacteria had infiltrated the large tubules. Furthermore, in teeth with advanced attrition, it was difficult to distinguish between the large tubules and the surrounding dentin matrix, and numerous bacteria were observed in both areas. These findings support the hypothesis that large tubules play a role in the pathway of caries formation in coronal dentin when incisal dentin is exposed by attrition. This suggests that early treatment of exposed dentin surfaces might be effective in preventing dental caries. (+info)
Craniofacial identification by computer-mediated superimposition.
(8/37)
Mass disasters are associated with a large number of fatalities, with victims being visually unidentifiable in most cases. Dental identification, although being an important and valuable identification method, is subject to the availability and quality of antemortem and postmortem dental records. This paper presents a simple-to-use method of human identification using an antemortem photograph showing anterior teeth with superimposition onto a postmortem image using specific features of Adobe Photoshop. We present cases and discuss the benefits and difficulties of this method. (+info)