The changing face of odontogenic infections.

PURPOSE: The purpose of this investigation was to compare characteristics of patients hospitalized with odontogenic infections during the 1980s to those of the 1990s. PATIENTS AND METHODS: This study was a retrospective record review that compared 2 cohorts of patients admitted to the same institution during two 81-month periods, one decade apart. Admission criteria were face or neck swelling suggesting abscess or cellulitis and one or more of the following: temperature above 38 degrees C, white blood cell (WBC) count greater than 10.8 x 10(3)/microL, or concern about airway compromise. Characteristics reviewed were age, gender, race, admission temperature, admission WBC count, fascial space(s) involved, tooth of etiology, duration of hospitalization, and bacteria isolated. Data were compared for statistical significance (P <.05). RESULTS: No significant differences were found between the 2 cohorts for age, gender, race, admission temperature, admission WBC count, space involvement, or length of stay (P <.05). One tooth (mandibular left first molar) of 52 was involved more frequently in the 1990 group (P <.03). Gram-positive cocci were isolated significantly more frequently from the 1990s patients than from the 1980s patients (P <.03). There were also significant differences (P <.02) between cohorts in the isolation frequency of individual genera, such as alpha-hemolytic Streptococci, coagulase negative staphylococci, Staphylococcus epidermidis, Bacteroides melanogenicus, beta-lactamase positive Bacteroides, Eikenella corrodens, and Neisseria species. Eighty-one percent of the bacteria cultured from the 1990s patients were resistant to one or more common antibiotics; 47% of these organisms were Staphylococcus aureus. CONCLUSION: No clinically significant differences existed in the characteristics of patients hospitalized with odontogenic infections between the 1980s and the 1990s. Although there were differences in the type and prevalence of bacteria isolated, this was probably a result of changes in nomenclature, identification protocols, and isolation techniques.

An in vitro evaluation of distractors used for osteogenesis.

OBJECTIVE: The objective of this investigation was to evaluate and compare the mechanical behaviors of distractors used for osteogenesis under various conditions by means of common engineering standards. STUDY DESIGN: Five groups of 5 synthetic mandibles were used in this study (N = 25). The first portion of the investigation compared mandibles without intervention (group A [controls]; n = 5), mandibles that had uniform osteotomies stabilized with an external distractor (group B; n = 5), and mandibles that had simulated sagittal osteotomies rigidly fixated with 3 positional screws (group C; n = 5). The second portion of the investigation compared uniform osteotomies (group B; n = 5) and uniform corticotomies (group D; n = 5) that were stabilized with the same external distractor. The last portion of the investigation compared osteotomies stabilized with an external distractor (group B; n = 5) and osteotomies stabilized with an internal distractor (group E; n = 5). Each construct was subjected to vertical loads on a mechanical testing unit. Common engineering standards, including yield load, yield displacement, maximum load, displacement at maximum load, and stiffness, were measured, recorded, and compared by means of a 1-way analysis of variance and a Scheffé multiple comparison test or independent-samples t test. The means between groups were considered significant for P < .05. A polynomial best-fit curve was calculated for the load/displacement data for each group. RESULTS: During the first portion of the investigation, no significant differences were noted between the control, rigidly fixated sagittal osteotomy, and external distractor with osteotomy groups for displacement at maximum load (P = .19). Significant differences were noted between groups for yield displacement (P = .009), yield load (P < .001), maximum load (P < .001), and stiffness (P < .007). Failures occurred in the control and rigidly fixated groups with fractures of the synthetic mandibles. Failures occurred in the external distractor group with permanent deformation or torsion of the pins. During the second portion of the experiment, no statistically significant differences were noted between the corticotomy and osteotomy groups in stiffness (P = .363), maximum load (P = .207), or yield displacement (P = .940). Statistically significant differences were noted between groups for yield load (P = .036) and displacement at maximum load (P = .010). Failures occurred in both groups with permanent deformation or torsion of the pins. During the last portion of the investigation, statistically significant differences were noted between the external distractor and internal distractor groups in yield load (P < .001), yield displacement (P < .001), maximum load (P = .001), and displacement at maximum load (P = .01); no significant differences were noted in stiffness (P = .71). Failures occurred in the external distractor group with permanent deformation or torsion of the pins. Failures occurred in the internal distractor group with fracture of the model or displacement beyond 30.0 mm. CONCLUSIONS: Different patterns of mechanical behavior were found between the control and rigidly fixated sagittal osteotomy groups and the external distractor group, between the corticotomy and osteotomy groups, and between the internal and external distractor groups.