Date of Award

Spring 1-1-2013

Document Type


Degree Name

Master of Science (MS)



First Advisor

Waliszewski, Michael P.

Second Advisor

Waliszewski, Kenneth

Third Advisor

Thompson, Geoffrey


Aim: This study was designed to analyze the third National Health and Nutrition Examination Survery (NHANES III) database to determine whether excessive overlap of the anterior teeth was related to an increase in structural dental problems.

Materials and Methods: The NHANES III database was procured from the

National Center for Healthcare Statistics for the purpose of investigating whether a relationship exists between tooth condition and occlusal characteristics of horizontal and vertical overlap. The sample population was limited to those aged 18-50 to incorporate those people who had both Restoration and Tooth Condition Scores and Occlusal Characteristics. The subject set was statistically analyzed using SAS v9.2 software to demonstrate any possible relationships.

Results: Our study reaffirmed the characteristics of naturally occurring

occlusions. It was shown that 59.5% of the population has a horizontal overlap between 1-3mm, 56% of the population has a vertical overlap of 1-3mm, and 4.6% of the population has an open bite. It was also suggested that the majority of the population has a sound dentition with 83.61% of all teeth recorded being sound. The anterior relationship to tooth condition score comparison was also made for individual at-risk teeth. Teeth numbers 9 (maxillary left central incisor), 12 (maxillary left first premolar), and 14 (maxillary left first molar) were analyzed. The vast majority of teeth were again found to be sound, approximately 85% (tooth 9), 75% (tooth 12), and 71% (tooth 14). No association was found between overlap and tooth condition scores for any individual tooth.

Conclusions: According to the NHANES III data file documentation currently

available through the Center for Disease Control and Prevention, no relationship exists

between the degree of anterior overlap and tooth condition. Due to large differences in the raw data found within this database when compared to previously published data, the reliability of the NHANES III database can be called into question.