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Lower Dentition (lower + dentition)
Selected AbstractsComparison of oral sensory function in complete denture and implant-supported prosthesis wearersJOURNAL OF ORAL REHABILITATION, Issue 3 2001Kyung-Soo Jang In order to compare the differences of part of the oral sensory functions among natural dentition, complete denture wearers and implant-supported prostheses wearers, tactile and pressure awareness was measured. Tactile sense was estimated by the thickness perception threshold between upper and lower dentition. Sensibility of pressure feeling was evaluated by threshold of lateral loading on tooth. Within this limited experiment, it could be concluded that an osseointegrated root form implant helped towards restoration of oral sensory functions. [source] Brief communication: High-resolution assessment of the dental developmental pattern and characterization of tooth tissue proportions in the late Upper Paleolithic child from La Madeleine, FranceAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Priscilla Bayle Abstract Affinities and differences in dental maturational patterns between modern humans and Neanderthals remain a matter of discussion. In particular, deciduous teeth are rare for Late Pleistocene humans, and few entire sequences have been detailed for their developmental status. Here, we report the results from the 3D virtual reconstruction and structural analysis of the deciduous lower dentition (nine teeth in situ) of the child from La Madeleine (LM4), France, the first Upper Paleolithic specimen detailed so far by means of high-resolution microtomography (,CT). With respect to the modern dental developmental standards, age at death of this individual is now more likely estimated within the interval 3,4 years. LM4 lacks the slight discrepancy between a proportionally advanced stage of mineralization of the deciduous first molar and a relatively delayed maturational level of the incisors, which is found in Neanderthals (Bayle et al.: J Hum Evol 56 [2009] 66,75). By using a Bayesian approach, we calculated the probability that its maturational sequence is found within the extant human variation as represented by a tomographic (CT) reference sample of 45 children scored according to the same protocol (Liversidge and Molleson: Am J Phys Anthropol 123 [2004] 172,180). Results show that the specific sequence of this Magdalenian individual is found three times in the comparative sample included in this study. LM4 absolute tooth size and relative dental tissue proportions are close to the modern human figures (characterized by proportionally reduced dentine volumes) and lie systematically below the values shown by the Neanderthal child from Roc de Marsal, France (OIS 5a). Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source] Early Complete Failures of Fixed Implant-Supported Prostheses in the Edentulous Maxilla: A 3-Year Analysis of 17 Consecutive Cluster Failure PatientsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2006Odont Dr/PhD, Torsten Jemt DDS ABSTRACT Background, Clusters of implant failures in the edentulous maxilla seem to occur in some patients. To create groups for analysis with higher numbers of these patients implies large original groups for inclusion. Purpose, The aim of this study was to retrospectively describe and compare a group of "cluster failure patients" with randomly selected patients treated in the edentulous maxilla. Materials and Methods, From a group of 1,267 consecutively treated patients in one clinic, all patients presenting failing fixed implant-supported prostheses within the first 3 years of follow-up were included. All patients were treated with turned titanium implants using two-stage surgery. A control group of equal number of patients were created for comparison. Data on patients were retrospectively retrieved from their records, and compared. Results, Seventeen patients (1.3%) met the inclusion criteria in the entire group. The bone resorption index revealed less bone quantity in the study group (p < .05) during implant placement, but there was no difference regarding primary implant stability at first-stage surgery. The distribution of short and long implants showed relatively higher number of short implants in the study group (p < .05), and more patients had a presurgical discussion on the risk of implant failure prior to treatment in this group (p < .05). Only 5 out of 102 implants (4.9%) were lost before prosthesis placement as compared to 38 and 25 lost implants during the following two years in the study group. Smoking habits and signs of bone loss related to periodontitis in the lower dentition were more frequent in the study group, but did not reach a significant level (p > .05). Conclusion, The results indicate that bone quantity, reflected in fixture length, has a significant impact on increased implant failure risk. Other factors of interest as predictors for implant failures could be smoking habits and also possibly signs of periodontitis in the opposing dentition. [source] Quantitative study of bite force during sleep associated bruxismJOURNAL OF ORAL REHABILITATION, Issue 5 2001K. Nishigawa Nocturnal bite force during sleep associated bruxism was measured in 10 subjects. Hard acrylic dental appliances were fabricated for the upper and lower dentitions of each subject. Miniature strain-gauge transducers were mounted to the upper dental appliance at the right and left first molar regions. In addition, thin metal plates that contact the strain-gauge transducers were attached to the lower dental appliance. After a 1-week familiarization with the appliances, nocturnal bite force was measured for three nights at the home of each subject. From the 30 recordings, 499 bruxism events that met the definition criteria were selected. The above described system was also used to measure the maximum voluntary bite forces during the daytime. The mean amplitude of detected bruxism events was 22·5 kgf (s.d. 13·0 kgf) and the mean duration was 7·1 s (s.d. 5·3 s). The highest amplitude of nocturnal bite force in individual subjects was 42·3 kgf (15·6,81·2 kgf). Maximum voluntary bite force during the daytime was 79·0 kgf (51·8,99·7 kgf) and the mean ratio of nocturnal/daytime maximum bite force was 53·1% (17·3,111·6%). These data indicate that nocturnal bite force during bruxism can exceed the amplitude of maximum voluntary bite force during the daytime. [source] | ||||||||||