The mixed dentition analysis described by Moyers, and later validated by Tanaka, was performed on 80 American blacks to compare prediction equations between Caucasians and blacks. For the black sample, separate regression formulas were determined for the 39 males and 41 females and the combined black sample. Although sexual dimorphism of tooth size was not a consideration in the Moyers predicti...

BACKGROUND When designing studies that have a binary outcome as the primary endpoint, the hypothesized proportion of patients in each population experiencing the endpoint of interest (i.e., π 1,π 2) plays an important role in sample size and power calculations. Point estimates for π 1 and π 2 are often calculated using historical data. However, the uncertainty in these estimates is rarely addre...

We consider the problem of sample size determination for three-level mixed-effects linear regression models for the analysis of clustered longitudinal data. Three-level designs are used in many areas, but in particular, multicenter randomized longitudinal clinical trials in medical or health-related research. In this case, level 1 represents measurement occasion, level 2 represents subject, and...

Although there have been suggestions that prenatal factors could affect crown dimensions (Bailit and Sung, Archs Oral Biol 13:155-166, 1968; Cohen, Baum, Garn, Osario and Nagy, in: Orofacial Growth and Development, Dahlberg and Graber, eds., Mouton Publishers, The Hague, 1977, pp 119-126), limitations of sample size and investigative design restrict conclusions on the magnitude of the influence...

OBJECTIVES To review the literature on Bolton's tooth-size discrepancies (TSD) with specific attention to the prevalence of TSD, and the possible influence of different classes of malocclusion, gender and racial group. Also examined were the validity of the standard deviations from Bolton's samples as an indicator of significant TSD, methods of measurement of TSD and their reproducibility. Base...

Objective. To examine the accuracy of Moyers 50%, Tanaka and Johnston, Ling and Wong and Jaroontham and Godfrey methods in predicting the mesio-distal crown width of the permanent canines and premolars (C + P(1) + P(2)) in Malay population. Materials and Methods. The study models of 240 Malay children (120 males and 120 females) aged 14 to 18 years, all free of any signs of dental pathology or ...

UNLABELLED Regards and Tribute: Late Dr Narender Hasija was a mentor and visionary in the light of knowledge and experience. We pay our regards with deepest gratitude to the departed soul to rest in peace. Bolton's ratios help in estimating overbite, overjet relationships, the effects of contemplated extractions on posterior occlusion, incisor relationships and identification of occlusal misfit...

In postnatal dental development, and in crown size itself, there is a demonstrable "distance gradient" so that teeth closer together within a jaw quadrant show higher correlations. Thus, adjacent teeth exhibit systematically higher commonality in both tooth formation and crown size than more remote teeth in the same quadrant, despite absolute differences in formation (calcification, root elonga...

internal inflammatory root resorption (iirr) is a rare condition of the root canal and if it is left untreated it may lead to destruction of the surrounding dental hard tissues. odontoclasts are responsible for this situation which can potentially perforate the root. many initiating factors have been mentioned for iirr, almost all causing chronic inflammation in the vital pulp. iirr is usually ...

Life history variables (LHV) in primates are closely correlated with the ages of tooth eruption, which are a useful proxy to predict growth and development in extant and extinct species. However, it is not known how tooth eruption ages interact with LHV in polymorphic species such as modern humans. African pygmies are at the one extreme in the range of human size variation. LHV in the Baka pygm...