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Purpose: The purpose of this study was to compare the stress transfer from a fixed restoration, supported by an implant restored with either a segmented or non-segmented implant abutment, connected to a simulated tooth with decreased foundational support by photoelastic evaluation.Methods: A photoelastic model of a human left mandible, edentulous posterior to the first premolar, was fabricated, with a 3.75×13 mm screw-type implant embedded within the edentulous area. The edentulous areas were restored with a three-unit fixed prosthetic restoration with the distal implant abutment connected to the simulated tooth abutment. The implant abutments consisted of either a segmented conical abutment or a non-segmented UCLA abutment. A hemiseptal periodontal defect was created by the removal of buccal and disto-buccal tissues to simulate decreased support caused by a 4 mm infrabony defect. Vertical occlusal loads were applied at fixed locations on the restorations for the simulated periodontal condition. The stresses which developed in the mandible were monitored photoelastically and recorded photographically.Results: Decrease of the foundational support of the tooth resulted in higher stresses transferred to the mesial and apical aspects of the implant as compared with those in the non-defect control condition. Similar results were obtained for both segmented and nonsegmented abutment restorations.Conclusion: Within the limitations of this study, application of load to the simulated abutment teeth with decreased periodontal support resulted in higher stresses around the supporting implant structure for both abutment designs. The distribution and intensity of the stresses were similar for segmented and nonsegmented abutments.

Statement of problem The effect of palatal support on various types of implant-supported maxillary overdenture designs has not been sufficiently assessed. Purpose The purpose of this study was to photoelastically evaluate the palatal support of 3 designs of maxillary implant-supported overdentures. Material and methods A photoelastic model of an edentulous maxilla was fabricated with four 3.75×13-mm 3i implants. Three maxillary overdenture designs were fabricated: a splinted Hader bar incorporating 2 distal ERA attachments with anterior clips; non-splinted Zaag 4-mm direct abutments and attachments; and nonsplinted Locator 2-mm direct abutments and attachments. All restorative components and attachments were fitted and observed for passivity of fit and alignment. The overdentures were first tested with complete palatal coverage. Unilateral 25-lb loads were applied at the left and right first molars and the incisive papilla area. The photoelastic effects were monitored and recorded photographically. The palatal area was removed from the 3 overdentures and the loading regimens were repeated. Results The highest stresses under central loading were seen with the splinted Hader bar and complete palatal coverage, followed by similar levels of stress with either Zaag or Locator attachments. After removal of the palate, the center load demonstrated greater differences between designs. The highest stresses were observed with the Hader bar, followed by the Zaag and then Locator attachments. Lack of palatal coverage demonstrated higher levels of stress around implants and visible supporting tissues. The unilateral load produced the highest stress for the splinted Hader bar, followed by Locator, and then Zaag. Conclusions Removal of the palatal support produced a greater effect and more concentrated stress difference for maxillary overdentures than differences between the attachment designs tested.

Textured implant surfaces are thought to enhance endosseous integration. Torque removal forces have been used as a biomechanical measure of anchorage, or endosseous integration, in which the greater forces required to remove implants may be interpreted as an increase in the strength of bony integration. The purpose of this study was to compare the torque resistance to removal of screw-shaped titanium implants having a dual acid-etched surface (Osseotite) with implants having either a machined surface, or a titanium plasma spray surface that exhibited a significantly more complex surface topography. Three custom screw-shaped implant types - machined, dual acid-etched (DAE), and titanium plasma sprayed (TPS) - were used in this study. Each implant surface was characterized by scanning electron microscopy and optical profilometry. One DAE implant was placed into each distal femur of eighteen adult New Zealand White rabbits along with one of the other implant types. Thus, each rabbit received two DAE implants and one each of the machined, or TPS, implants. All implants measured 3.25 mm in diameter x 4.00 mm in length without holes, grooves or slots to resist rotation. Eighteen rabbits were used for reverse torque measurements. Groups of six rabbits were sacrificed following one, two and three month healing periods. Implants were removed by reverse torque rotation with a digital torque-measuring device. Three implants with the machined surface preparation failed to achieve endosseous integration. All other implants were anchored by bone. Mean torque values for machined, DAE and TPS implants at one, two and three months were 6.00+/-0.64 N-cm, 9.07+/-0.67 N-cm and 6.73+/-0.95 N-cm; 21.86+/-1.37 N-cm, 27.63+/-3.41 N-cm and 27.40+/-3.89 N-cm; and 27.48+/-1.61 N-cm, 44.28+/-4.53 N-cm and 59.23+/-3.88 N-cm, respectively. Clearly, at the earliest time point the stability of DAE implants was comparable to that of TPS implants, while that of the machined implants was an order of magnitude lower. The TPS implants increased resistance to reverse torque removal over the three-month period. The results of this study confirm our previous results that demonstrated enhanced bony anchorage to dual acid-etched implants as compared to machined implants. Furthermore, the present results indicate that dual acid etching of titanium enhances early endosseous integration to a level which is comparable to that achieved by the topographically more complex TPS surfaces.

Patients with a tracheostomy stoma experience compromised speech due to the associated changes in airflow patterns. Prosthetic obturation of the stoma restores the normal airflow patterns required for proper speech. Standard stent tubes may not adequately obturate the defect and may be uncomfortable to wear. The fabrication of a custom silicone tracheostomal prosthesis, incorporating a speaking valve, provides proper obturation of the defect and improved patient comfort, fit, and function. This article presents the procedures used to make a functional impression of a tracheostomy stoma and to fabricate a custom tracheostomal prosthesis. (J Prosthet Dent 2000;83:578-81.)

Fractionated stereotactic radiation therapy is a useful new approach for treating a number of intracranial neoplasms including meningiomas, pituitary adenomas, craniopharyngiomas, and recurrent gliomas. For the majority of these we employ a conventional fractionation scheme of 180 cGy per fraction for 25 to 30 fractions, using a modified Gill–Thomas–Cosman (GTC) relocatable frame to accommodate fractionated delivery. The GTC system uses a custom acrylic dental appliance to set the frame position and an occipital plate and Velcro straps fix the head in place. Daily reproducibility is evaluated through use of a “depth helmet,” a plastic hemispherical shell containing 25 holes at regularly spaced intervals. The depth helmet attaches to the GTC frame and the distance from the shell to the patient's head is recorded at each of the 25 positions. This paper describes a new simplified approach to the quantitative assessment of day-to-day variability in head fixation using the depth helmet measurements. This approach avoids the need to try and decide on the relative merit of 25 numerical differences at each fitting and provides a straightforward mathematical and conceptual framework for the description of fit and clinical decision making. The mathematical analysis and computer program we have developed uses all 25 measurements to provide a single three-dimensional displacement vector as well as displacement values in the three principal patient dimensions. Measurements at each of the 25 depth helmet positions are automatically separated into three principal axes corresponding to the patients left/right (x), anterior/posterior (y), and superior/inferior (z) using the spherical relations: x = r sin(Φ) cos(θ), y = r sin(Φ) sin(θ), z = r cos(Φ), where θ and Φ are the polar and azimuthal angles respectively and ris the distance from the center of the depth helmet to the surface of the patient's head. For each patient, a set of initial measurements is taken at the CT scanner with the patient in the treatment (supine) position. Because treatment planning is based on the CT scan, this serves as the baseline from which subsequent deviations are recorded. In an analysis of our first 30 patients representing over 750 fractions, the mean RMS deviation, that is, the mean three-dimensional displacement from baseline, was 0.468 ± 0.296 mm. Among individual patients the range was 0.169 mm to 1.438 mm. A closer analysis suggests that in-plane (AP/PA-lateral) deviations occur randomly. Deviations along the superior/inferior direction are greater than those in-plane, and in several patients a small shift along this axis, possibly due to a loosening or stretching of the Velcro straps, has been noted over time. We have found our method to be a useful indicator of day-to-day reproducibility, allowing ready identification and correction of three-dimensional shifts relative to the patient axes. Based on our initial analysis, we can now define quantitative limits of acceptability in repositioning for subsequent fractionated delivery.

Roughened implant surfaces are thought to enhance osseointegration. Torque removal forces have been used as a biomechanical measure of anchorage or osseointegration in which the greater forces required to remove implants may be interpreted as an increase in the strength of osseointegration. The purpose of this study was to compare the torque resistance to removal of screw shaped titanium implants having an acid etched (HC1/H2SO4) surface (Osseotite) with implants having a machined surface. Two custom screw shaped implants, 1 acid etched and the other machined, were placed into the distal femurs of 10 adult New Zealand White rabbits. These implants were 3.25 mm in diameter x 4.00 mm in length without holes, grooves or slots to resist rotation. Following a 2 month healing period, the implants were removed under reverse torque rotation with a digital torque measuring device. Two implants with the machined surface preparation failed to achieve osseointegration. All other implants were found to be anchored to bone. Resistance to torque removal was found to be 4 x greater for the implants with the acid etched surface as compared to the implants with the machined surface. The mean torque values were 20.50 +/- 6.59 N cm and 4.95 +/- 1.61 N cm for the acid etched and machined surfaces respectively. The results of this study suggest that chemical etching of the titanium implant surface significantly increases the strength of osseointegration as determined by resistance to reverse torque rotation.

Resection of head and neck tumors often results in severe facial disfigurement and functional disabilities. Superior rehabilitation efforts rely on close collaboration between the resection surgeon, reconstructive surgeon, and the maxillofacial prosthodontist. Trauma patients are best rehabilitated surgically, whereas patients with head and neck tumors are best rehabilitated prosthetically in combination with specific surgical reconstruction procedures. This article describes these modifications. Surgical advancements such as microvascular free flaps and endosseous implants have greatly enhanced rehabilitative efforts.

A clinical study of 23 craniofacial implants placed in 11 nasal defects was conducted over a 7-year period. Implant-retained nasal prostheses were fabricated, implant success rate was determined, and the soft tissue responses were recorded at 6-month intervals. No data were gathered on two implants because of patient death. The implant success rate was 71.4% ( 15 21 ) but varied significantly by anatomic site. The implant success rate in the glabella was 0% ( 0 4 ), whereas the success rate in the anterior nasal floor was 88.1% ( 15 17 ). All implant failures occurred within the first year of loading. A five-point scale was used to record the health of the peri-implant soft tissues, and the patients were followed up from 6 to 74 months. The unit of measure was a visit/site, and a unit was assigned for each instance an implant site was evaluated. Evaluations were conducted at 6-month intervals for a total of 76 visit/sites for the study period. The results revealed that 85.5% ( 65 76 ) of the visit/sites demonstrated an absence of inflammation; 10.5% ( 8 76 ) of the visit/sites demonstrated slight redness; 1.3% ( 1 76 ) demonstrated peri-implant red and moist tissues; 2.6% ( 2 76 ) demonstrated granulation tissue associated with the implants; and 0% ( 0 76 ) demonstrated infection of the peri-implant soft tissues. Severe soft tissue reactions around implants placed in the anterior nasal floor are rare.

A clinical study of 40 craniofacial implants placed in 13 auricular defects was conducted over a 6-year period. Implant-retained prostheses were fabricated, the implant success rate was determined, and the soft tissue responses were recorded at regular intervals. All of the implants became osseointegrated and none demonstrated failure during the study period. A five-point scale was used to record the health of the peri-implant soft tissues and the patients were followed up for up to 69 months. The results were as follows: 55.1% of the visit/sites demonstrated an absence of inflammation; 32.3% of the visit/sites demonstrated slight redness; 4.7% demonstrated red and moist peri-implant tissues; 5.5% demonstrated granulation tissue associated with the implants; and in 2.4% of the implants, infection of the peri-implant soft tissues was noted. Good patient hygiene compliance combined with thin and immobile peri-implant soft tissues resulted in minimal soft tissue complications.

Osseointegrated implants can be used to facilitate retention stability and support for facial and intraoral prostheses used to restore head and neck defects. Preliminary studies indicate that in nonirradiated maxillectomy patients the success rates are about 75%. In the reconstructed mandible the results appear to be more favorable--over 90% for implants placed in free nonvascularized bone grafts and over 90% for free revascularized bone grafts. Similar high success rates have been observed for most sites used to support facial prostheses. Success rates for auricular sites exceed 95% and for floor of nose sites success rates exceed 90%. Success rates have been lower (77%) for implants placed in the frontal bone for retention of orbital prostheses. Success rates for irradiated bone sites have been lower and range from 60.4% in the maxilla to 68.6% in facial bone sites. Of greater concern is that most implants placed in irradiated sites are beginning to show signs of impending failure.

The collection of autologous platelet-rich plasma (PRP) has demonstrated favorable affects on wound healing in compromised patients. The purpose of this study was to evaluate the expression of PDGF, bFGF, and TGF-beta in irradiated and nonirradiated bone in a rabbit tibia model and the ability of PRP to increase growth factor expression when added to autogenous bone graft in a rabbit cranial defect model.Ten New Zealand White rabbit tibiae and calvariae were utilized for this study. Tibiae were irradiated at 60 to 70 cGy and evaluated for expression of PDGF, bFGF, and TGF-beta. Rabbit calvariae were also analyzed after grafting with autogenous bone and PRP for determination of growth factor expression.Decreased expression of PDGF, bFGF, and TGF-beta was seen in cortical and cancellous bone samples when irradiated bone was compared to nonirradiated rabbit tibiae. An increase in PDGF, bFGF, and TGF-beta expression was detected in cortical autogenous bone grafts with PRP at 1 and 2 months compared to autogenous bone alone.In this study, growth factors, which were decreased in irradiated cortical and cancellous bone, showed increased expression at 1 and 2 months when PRP was added to autogenous bone grafts. Thus, PRP may have potential therapeutic applications when bone grafting is required in patients with reduced bone vascularity, including patients with previous head and neck irradiation, diabetes, and smoking habits.Decreased expression of PDGF, bFGF, and TGF-beta was seen in radiated rabbit tibia as compared to nonirradiated controls, and increased expression of these growth factors was seen in PRP-containing autogenous bone grafts.

This in vitro study determined the stress distribution around an implant placed in a posterior edentulous maxillary model with simulated sinus grafts that had different degrees of stiffness.The composite photoelastic model with a standard threaded implant consisted of simulated crestal cortical, cancellous, sinus cortical, and grafted bone. The graft maturation process and inherent graft quality were represented in the model by varying the stiffness of the graft. Prior to placement of the simulated graft, axial and inclined loads were applied to the implant The stresses that developed in the supporting structures were analyzed photoelastically. The graft was then placed and the testing procedure was repeated over 4 consecutive days, during which time the simulated graft stiffened.The stress analysis indicated that before placement of the simulated graft, loading on the implant transferred the highest stresses to cortical bone. The presence of the simulated graft transferred stress from the native bone simulants to the simulated grafted bone.As the stiffness of the graft increased, a more equitable stress distribution was observed in the multilayer bone surrounding the implant.Loading of an implant in a less stiff grafted sinus could lead to overloading of the native bone as well as the maturing grafted bone.

Statement of problem There is some question about whether implant abutment selection affects the transfer of load between connected implants and natural teeth. Purpose The purpose of this study was to compare stress transfer patterns with either 1 or 2 posterior implants connected to a single anteriorly located simulated natural tooth with either 1 or 2 segmented and nonsegmented implant abutments under relevant functional loads by use of the photoelastic stress analysis technique. Material and methods A model of a human left mandible, edentulous posterior to the first premolar, with two 3.75-mm × 13-mm screw-type implants embedded within the edentulous area, was fabricated from photoelastic materials. The implants were in the first and second molar positions. Two fixed partial denture prosthetic restorations were fabricated with either segmented conical abutments or nonsegmented UCLA abutments. Vertical occlusal loads were applied at fixed locations on the restorations. The photoelastic stress fringes that developed in the supporting mandible were monitored visually and recorded photographically. The stress intensity (number of fringes), stress concentrations (closeness of fringes), and their locations were subjectively compared. Results Loading on the restoration over the simulated tooth generated apical stresses of similar intensity (fringe order) at the tooth and the first molar implant for both abutment types. Low-level stress was transferred to the second molar implant. Loading directed on the implant-supported region of the restoration demonstrated low transfer of stress to the simulated tooth. Nonvertical stress transfer with slightly higher intensity was observed for the nonsegmented abutment. Conclusion Within the limitations of this simulation study, stress distribution and intensity for the 2 implant conditions was similar for segmented and nonsegmented abutment designs. Magnitude of stresses observed for both abutment designs was similar for the single implant condition. Vertical loading produced more nonaxial stresses away from the force applied for the 1 implant condition with the nonsegmented abutment. Direct loading results were similar for both abutment designs. Specific recommendations for selection of implant abutment and application should be based on clinical criteria.

This study assesses the success rate of osseous integrated implantation in assisting the prosthetic obturation of maxillectomy defects. Twenty-three patients received a total of 85 osseous integrated implants used for retaining maxillary obturators between 1985 and 1993. Defects include 13 radical maxillectomies, 5 premaxillary resections, 4 subtotal maxillectomies, and 1 soft-palate resection. Thirteen patients (50 implants) received a radiation dose ranging from 5,040 to 7,940 cGy. Implants can be placed at the time of ablation or subsequently. Efforts were made to spare uninvolved segments of the maxilla, especially premaxillary segments and tuberosities, at the time of ablation. Following a 6-month period of integration, implants were uncovered and utilized in prosthetic rehabilitation. Specific implant sites reveal variable success rates, with the anterior maxilla being 86% successful compared with the posterior maxilla being 57% successful. Radiation reduces the success rate from 80% to 55%, although it does not eliminate a patient from being a candidate for implantation. Prosthetic rehabilitation of large maxillary defects can be greatly facilitated with the use of osseous integrated implants in the remaining midfacial skeleton.

Statement of Problem. The specific degree of retention for overdenture attachments is unknown in relation to design, location, and alignment to supporting dental implants. Purpose. The purpose of this study was to evaluate the initial retention characteristics of 5 implant maxillary overdenture designs under in vitro dislodging forces. Material and Methods. A simulated edentulous maxilla was fabricated with 4 screw-type 3.75 × 13-mm implants anteriorly. Five overdenture designs with the following attachments were evaluated: 4 plastic Hader clips with an EDS bar; 2 plastic anterior Hader clips with an identical EDS bar; 2 Hader clips with 2 posterior ERA attachments; 3 Zaag attachments on a bar; and 4 Zaag attachments with no bar. Overdentures were fabricated with full palatal coverage. Each design was subjected to 10 consecutive retention pulls on a universal testing machine. Data were subjected to analysis of variance and t tests to determine differences. Results. The highest average value after 10 pulls was 19.8 lb for the combination ERA and Hader clip design. The lowest retentive values were recorded for the 2 and 4 Hader clip designs (5.08 ± 0.89 lb and 5.06 ± 0.67 lb, respectively). Retention decreased over the course of consecutive pulls for all designs, especially for the most retentive designs. The smallest retention decrease occurred with the least retentive designs. Conclusion. The results of this in vitro study suggest that the precise selection and placement of attachments may affect the clinical success of maxillary implant-retained overdentures. (J Prosthet Dent 2001;86:603-7.)

Statement of problem. Controversy exists regarding the connection of implants to natural teeth. Purpose. This simulation study measured photoelastically the biologic behavior of implants. Stress transfer patterns with variable implant support and simulated natural teeth through rigid and nonrigid connection were examined under simulated functional loads. Material and methods. A photoelastic model of a human left mandible edentulous distal to first premolar was fabricated having 2 screw type implants (3.75 × 13 mm) embedded within the edentulous area. Two fixed prosthetic restorations were fabricated with either a nonsplinted proximal contact or a soldered proximal contact, and cast precision dowel attachment between implant areas and simulated tooth. Simulated vertical occlusal loads were applied at fixed locations on the restorations. Stresses, which developed in the supporting structure, were monitored photoelastically and recorded photographically. Results. The rigid connector in the 1 implant situation caused only slightly higher stresses in the supporting structure than the nonrigid connector. The distally loaded 1 and 2 implant-supported restoration produced the highest apical stresses, which occurred at the distal implant. The rigid connector demonstrated the greatest stress transfer in the 2 implant-supported restoration. Conclusions. Lower stresses apical to the tooth or implant occurred with forces applied further from the supporting abutment. Although the least stress was observed when using a nonrigid connector, the rigid connector in particular situations caused only slightly higher stresses in the supporting structure. The rigid connector demonstrated more widespread stress transfer in the 2 implant-supported restoration. Recommendations for selection of connector design should be based on sound clinical periodontal health of a tooth and the support provided by implants. (J Prosthet Dent 1999;81:696-703.)

Statement of problem. The success rates of osseointegrated implants used to restore patients who were irradiated for head and neck tumors are influenced by radiation-induced changes in the hard and soft tissues. Purpose. This article examined, by review of the literature, current perspectives on the restoration of irradiated patients using osseointegrated implants. Results. In published reports that investigated both intraoral and extraoral applications, irradiation decreased implant success rates and the amount of reduction was dependent on the location within the craniofacial skeleton. The limited number of implants and patients in these studies precludes definitive conclusions regarding the efficacy of placing implants into irradiated tissues. The implants placed into the irradiated anterior mandible have demonstrated an acceptable implant success rate of 94% to 100% with a minimal risk of osteoradionecrosis. The efficacy of implants in the posterior mandible has not been examined. Implant success rates ranged from 69% to 95% in the irradiated maxilla for intraoral applications. Extraoral applications demonstrated excellent implant success rates in the temporal bone (91% to 100%). The rates in the anterior nasal floor have varied from 50% to 100%. The implant success rates in the frontal bone decreased as the length of the studies increased (96% to 33%). The long-term efficacy of implants in the irradiated frontal bone is poor. (J Prosthet Dent 1998;79:641-7.)

Purpose. A clinical study of 23 craniofacial implants placed in 8 irradiated and nonirradiated orbital defects was conducted over a 7-year period. Material and methods. Implant-retained orbital prostheses were fabricated, implant success rate was determined, and the soft tissue responses were recorded at 6-month intervals. As a result of patient death, no data were gathered on three implants. A five-point scale was used to record the health of the peri-implant soft tissues and the patients were followed from 9 to 72 months. The unit of measure was a visit/site that was assigned for each instance an implant site was evaluated. Evaluations were conducted at 6-month intervals, and for the study period, there were 80 visit/sites. Results. The study revealed that 42.5% (34/80) of the visit/sites demonstrated an absence of inflammation; 23.7% (19/80) of visit/sites demonstrated slight redness; 13.8% (11/80) demonstrated peri-implant red and moist tissues; 6.2% (5/80) demonstrated granulation tissue associated with the implants; and 13.8% (11/80) infection of the peri-implant soft tissues was noted. Implant success rate was 35% (7/20); implant success rate in the nonradiated patients was 37.5% (3/8) and the success rate for radiated patients was 33.3% (4/12). Implants placed in the orbital region demonstrated a high failure rate. Most implant failures occurred late as opposed to early in the study period. Conclusion. Orbital implants should be placed in patients who understand that long-term success rates may be low and require meticulous hygiene maintenance. (J Prosthet Dent 1998;79:304-9.)

Restoration of the edentulous maxilla with implant retained and supported prosthesis is challenging because of inherent anatomic limitations present after the loss of teeth. A fixed-removable prosthesis is one treatment choice for restoration of the edentulous maxilla with implants. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favorable biomechanical stress distribution to the implants. This article presents a procedure for fabrication of a fixed-removable prosthesis with a precision milled bar, Hader clip attachments, and a superstructure prosthesis. The criteria for patient selection and the advantages and disadvantages of this prosthesis are discussed.

Edentulous maxillae can be restored with implant supported fixed restorations containing denture teeth on a metal framework, implant-retained removable overlay prostheses, or porcelain fused-to-metal fixed prostheses. Esthetics and hygiene access are two important factors in determining the restoration best suited for each patient. Treatment planning considerations and treatment procedures for the various techniques are discussed.

Toxic-shock syndrome (TSS) is believed to be caused by a toxin produced by Staphylococcus aureus. An exotoxin has been identified that is associated with strains of S. aureus isolated from patients with TSS. Coded strains of S. aureus were tested for the presence of the exotoxin by polyacrylamide gel isoelectric focusing. Sixty isolates of S. aureus were tested; 28 (100%) of 28 isolates from patients with TSS but only five (16%) of 32 control isolates produced the toxin (P much less than 0.001). This protein exotoxin, which was purified by differential precipitation with ethanol and thin-layer isoelectric focusing, had an isoelectric point of 7.2. When tested by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the toxin migrated as a homogeneous protein with a molecular weight of 22,000. The exotoxin produced fever in rabbits and enhanced susceptibility to lethal shock caused by endotoxin. Other biologic properties of the exotoxin included lymphocyte mitogenicity and the capacity to suppress synthesis of IgM antibody to sheep erythrocytes.

Vaginal isolates ofStaphylococcus aureusfrom 19 patients with menstrual toxic shock syndrome elaborated high concentrations of pyrogenic exotoxin C, but produced low amounts of hemolysin, ...