Evaluation of orbital stress dissipation in pediatric and adult skulls using electronic speckle pattern interferometry.

OBJECTIVES: To measure and quantitatively compare the degree of force dissipation in pediatric and adult skulls subjected to similar dynamic forces. DESIGN: An anatomical study using electronic speckle pattern interferometry, which allows generation of displacement vectors after application of a force. SUBJECTS: Five human skulls (3 pediatric and 2 adult). INTERVENTION: Each skull was subjected to a reproducible and quantifiable force created by a steel ball pendulum striking a precise periorbital focus: (1) infraorbital foramen, (2) supraorbital notch, (3) malar eminence, and (4) nasofrontal suture. Electronic speckle pattern interferometry was used to construct interferogram fringe patterns to determine skull regions with the greatest degree of displacement. RESULTS: Interferogram analysis revealed that the adult skull has a tendency to dissipate force with minimal resultant displacement. In contrast, the pediatric skulls demonstrated greater displacements (ie, increased fringe density) at the same periorbital foci. CONCLUSIONS: The pediatric skull dissipates periorbital stress differently than the adult skull, as illustrated by quantitative interferogram analysis. This finding parallels clinical data that demonstrate a varying pattern of fractures in pediatric and adult skulls related to craniofacial development.

The impact of airbags and seat belts on the incidence and severity of maxillofacial injuries in automobile accidents in New York State.

OBJECTIVE: To evaluate the effect driver-side and passenger-side airbags have had on the incidence and severity of maxillofacial trauma in victims of automobile accidents. DESIGN: Retrospective analysis of all automobile (passenger cars and light trucks) accidents reported in 1994. SETTING: New York State. PATIENTS: Of the 595910 individuals involved in motor vehicle accidents in New York in 1994, 377054 individuals were initially selected from accidents involving cars and light trucks. Of this subset, 164238 drivers and 62755 right front passengers were selected for analysis. MAIN OUTCOME MEASURES: Each case is described in a single record with approximately 100 variables describing the accident, eg, vehicle, safety equipment installed and utilized or deployed, occupant position, patient demographics, International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnoses, and procedural treatments rendered. A maxillofacial trauma severity scale was devised, based on the ICD-9-CM diagnoses. RESULTS: Individuals using airbags and seat belts sustained facial injuries at a rate of 1 in 449, compared with a rate of 1 in 40 for individuals who did not use seat belts or airbags (P<.001). Those using airbags alone sustained facial injuries at the intermediate rate of 1 in 148, and victims using seat belts without airbags demonstrated an injury rate of 1 in 217 (P<.001). CONCLUSION: Use of driver-side airbags, when combined with use of seat belts, has resulted in a decrease in the incidence and severity of maxillofacial trauma.