Sexual dimorphisms in three-dimensional masticatory muscle attachment morphometry regulates temporomandibular joint mechanics.

Temporomandibular joint (TMJ) disorders disproportionally affect females, with female to male prevalence varying from 3:1 to 8:1. Sexual dimorphisms in masticatory muscle attachment morphometry and association with craniofacial size, critical for understanding sex-differences in TMJ function, have not been reported. The objective of this study was to determine sex-specific differences in three-dimensional (3D) TMJ muscle attachment morphometry and craniofacial sizes and their impact on TMJ mechanics.

Effect of scan substrates on accuracy of 7 intraoral digital impression systems using human maxilla model.

Objective: This study aimed to determine how the accuracy of digital impressions was affected by four common dental substrates using seven prevalent IOS systems to scan the complete arch of a human maxilla.

Setting And Sample Population: The Department of Oral Rehabilitation at the Medical University of South Carolina. A single cadaver maxilla.

Evaluation of the trueness and precision of complete arch digital impressions on a human maxilla using seven different intraoral digital impression systems and a laboratory scanner.

Objectives: An impression accuracy study using a cadaver maxilla was performed using both prepared and intact teeth as well as palatal tissue.

Materials And Methods: Three crown preparations were performed on a cadaver maxilla. Seven different digital impression systems along with polyvinylsiloxane impressions were used to create digital models of the maxilla.

Three-dimensional temporomandibular joint muscle attachment morphometry and its impacts on musculoskeletal modeling.

In musculoskeletal models of the human temporomandibular joint (TMJ), muscles are typically represented by force vectors that connect approximate muscle origin and insertion centroids (centroid-to-centroid force vectors). This simplification assumes equivalent moment arms and muscle lengths for all fibers within a muscle even with complex geometry and may result in inaccurate estimations of muscle force and joint loading. The objectives of this study were to quantify the three-dimensional (3D) human TMJ muscle attachment morphometry and examine its impact on TMJ mechanics.

Electrical Conductivity Method to Determine Sexual Dimorphisms in Human Temporomandibular Disc Fixed Charge Density.

To investigate potential mechanisms associated with the increased prevalence of temporomandibular joint (TMJ) disorders among women, the study objective was to determine sex-dependent and region-dependent differences in fixed charge density (FCD) using an electrical conductivity method. Seventeen TMJ discs were harvested from nine males (77 ± 4 years) and eight females (86 ± 4 years). Specimens were prepared from the anterior band, posterior band, intermediate zone, medial disc and lateral disc.