On Tooth Size and Oceanic Prehistory

1983 ◽  
Vol 24 (2) ◽  
pp. 243-246 ◽  
Author(s):  
Edward F. Harris ◽  
Richard J. Smith ◽  
C. Loring Brace ◽  
Robert J. Hinton
Keyword(s):  
Tooth Size ◽  
Oceanic Prehistory

Sri Lankan Cleft Lip and Palate Study Model Analysis: Clefts of the Secondary Palate

1993 ◽  
Vol 30 (2) ◽  
pp. 227-230 ◽  
Author(s):  
Andrew Mccance ◽  
David Roberts-Harry ◽  
Martyn Sherriff ◽  
Michael Mars ◽  
William J.B. Houston
Keyword(s):  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Model Analysis ◽  
Control Group ◽  
Tooth Size ◽  
Sri Lankan ◽  
Control Groups ◽  
Secondary Palate ◽  
Comparable Control ◽  
And Control

The study models of a group of adult Sri Lankan patients with clefts of the secondary palate were investigated. Tooth-size and arch-dimension comparisons were made with a comparable control group. Significant differences were found between the cleft and control groups in tooth sizes, chord lengths, and arch widths. The cleft group dimensions were generally smaller than those of the control group. Overjets were larger in the cleft group.

Effect of Contact Ratio on Spur Gear Dynamic Load With No Tooth Profile Modifications

1996 ◽  
Vol 118 (3) ◽  
pp. 439-443 ◽  
Author(s):  
Chuen-Huei Liou ◽  
Hsiang Hsi Lin ◽  
F. B. Oswald ◽  
D. P. Townsend
Keyword(s):  
Dynamic Load ◽  
Spur Gear ◽  
Tooth Size ◽  
Contact Ratio ◽  
Gear Dynamics ◽  
Wide Range ◽  
Gear Contact ◽  
Center Distance ◽  
Selection Of ◽  
Better Than

This paper presents a computer simulation showing how the gear contact ratio affects the dynamic load on a spur gear transmission. The contact ratio can be affected by the tooth addendum, the pressure angle, the tooth size (diametral pitch), and the center distance. The analysis presented in this paper was performed by using the NASA gear dynamics code DANST. In the analysis, the contact ratio was varied over the range 1.20 to 2.40 by changing the length of the tooth addendum. In order to simplify the analysis, other parameters related to contact ratio were held constant. The contact ratio was found to have a significant influence on gear dynamics. Over a wide range of operating speeds, a contact ratio close to 2.0 minimized dynamic load. For low-contact-ratio gears (contact ratio less than two), increasing the contact ratio reduced gear dynamic load. For high-contact-ratio gears (contact ratio equal to or greater than 2.0), the selection of contact ratio should take into consideration the intended operating speeds. In general, high-contact-ratio gears minimized dynamic load better than low-contact-ratio gears.

TOOTH SIZE VARIABILITY, INBREEDING, AND EVOLUTION

1966 ◽  
Vol 134 (2 The Biology o) ◽  
pp. 616-623 ◽  
Author(s):  
Howard L. Bailit
Keyword(s):  
Tooth Size ◽  
Size Variability

Secondary Dentition Characteristics in Children With Nonsyndromic Unilateral Cleft Lip and Palate

2018 ◽  
Vol 55 (4) ◽  
pp. 582-589 ◽  
Author(s):  
Elaine Li Yen Tan ◽  
Meaw Charm Kuek ◽  
Hung Chew Wong ◽  
Serene Ai Kiang Ong ◽  
Mimi Yow
Keyword(s):  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Permanent Teeth ◽  
Tooth Size ◽  
Dental Anomalies ◽  
Supernumerary Teeth ◽  
High Prevalence ◽  
Dental Records ◽  
Congenitally Missing ◽  
Maxillary Region

Objective: Children with cleft lip and palate are reported to be commonly associated with higher prevalence of dental anomalies such as hypodontia, supernumeraries, and abnormalities in tooth size, shape, and position. This study investigated the prevalence of dental anomalies in a longitudinal cohort of children with unilateral cleft lip and palate (UCLP). Design: The study was a retrospective analysis of radiographs, study models, and treatment notes. Patients: Sixty patients with repaired UCLP aged 13 years old with complete dental records dating from 5 years of age were included. Methods: Study casts, dental panoramic, anterior maxillary occlusal, and periapical radiographs of the patients were examined for cleft-sidedness, congenitally missing permanent teeth, supernumerary teeth, microdontic, and macrodontic teeth in the anterior maxillary region, presence of malformed permanent cleft-sided lateral incisor and its morphology (peg-shaped, conical shaped, canine-formed), positions of the permanent lateral incisors relative to the cleft side and presence of rotated cleft-sided central incisors. Results: Of the 60 patients studied, 63.3% had hypodontia, 21.7% had supernumerary teeth, 69.6% had microdontia, and 12.5% had macrodontia. All of the cleft-sided permanent lateral incisors had associated anomalies, with a large proportion (43.1%) missing; and when present in 31 subjects, the majority (90.3%) was positioned distal to the cleft. Most of the cleft-sided permanent central incisors were rotated if present, and prevalent at 86.7%. Conclusion: A high prevalence of dental anomalies was observed in this sample of children with UCLP.

A Rare Tooth Anomaly (Double Teeth) in Deciduous Teeth: A Case Report

2021 ◽  
Author(s):  
Fataneh Ghorbanyjavadpour
Keyword(s):  
Case Report ◽  
Lateral Incisor ◽  
Permanent Teeth ◽  
Deciduous Teeth ◽  
Tooth Size ◽  
Genetic Characteristics ◽  
Size And Shape ◽  
Size Discrepancy ◽  
Tooth Size Discrepancy ◽  
Double Teeth

Introduction: The Size and shape of the teeth are genetic characteristics. Anomaly in tooth size and shape is due to disturbances in a sequence of morph differentiation and his to differentiation in tooth bud formation periods and is more common in permanent dentition than deciduous teeth. The most common tooth size discrepancy is in the upper lateral incisor and upper and lowers 2nd premolar teeth. About 5% of malocclusions are due to tooth size discrepancy. For having the best occlusion, we must have the appropriate size and shape of teeth. As there is a relation between deciduous and permanent teeth, proper evaluation and timely intervention are essential for achieving a good occlusion in anterior and posterior segments of permanent teeth. Thus we need interceptive orthodontic in mixed dentition period with a good treatment plan for removing the malformed tooth at the proper time and appliance therapy for eruption guidance of other teeth. Case Report: A rare tooth anomaly (double teeth) in deciduous teeth: The case reported here is a 9- years old boy with a delayed eruption of the right lower permanent lateral incisor and gemination of lower right deciduous canine and crowded upper incisors that refer to the orthodontic department of dental school of Ahvaz Jundishapur University of Medical Sciences on7th October of 2020. Conclusion: After creating patient’s file, the further steps of molding from the patient and gathering all diagnostic records such as panoramic radiography, intraoral photography was carried out and ordered to remove the malformed baby tooth afterward. In the next stage, on the patient’s treatment, we installed a strap onto the patient’s first permanent molars, remolded them, then created a lingual arch to maintain the vegetative space in the lower permanent canine and prevent its collapse, and increased the patient’s overbite.

Age related tooth size variation in the Lengua Indians of Paraguay

1985 ◽  
Vol 75 (3) ◽  
pp. 341-348
Author(s):  
Julius A. Kieser ◽  
H. T. Groeneveld ◽  
Charles B. Preston
Keyword(s):  
Size Variation ◽  
Tooth Size ◽  
Age Related

scholarly journals Posterior tooth size discrepancy

2008 ◽  
Vol 11 (1) ◽  
pp. 8-22 ◽  
Author(s):  
Arlette Oueiss ◽  
Christine Marchal-Sixou ◽  
Ahmad Dallow ◽  
Pascal Baron ◽  
Jacques Faure
Keyword(s):  
Tooth Size ◽  
Posterior Tooth ◽  
Size Discrepancy ◽  
Tooth Size Discrepancy
Sign in / Sign up

Export Citation Format

Share Document