Reproducibility of prompts in computer-aided detection (CAD) of breast cancer

AIM

We evaluated the reproducibility of prompts using the R2 ImageChecker M2000 computer-aided detection (CAD) system.

MATERIALS AND METHODS

Forty selected two-view mammograms of women with breast cancer were digitized and analysed using the ImageChecker on 10 separate occasions. The mammograms were chosen to provide both straightforward and subtle signs of malignancy. Data analysed included mammographic abnormality, pathology, and whether the cancer was prompted or given an emphasized prompt.

RESULTS

Correct prompts were generated in 86 out of 100 occasions for screen-detected cancers. Reproducibility was less in the other categories of more subtle cancers: 21% for cancers previously missed by CAD, a group that contained more grade 1 and small (<10 mm) tumours. Prompts for calcifications were more reproducible than those for masses (76% versus 53%) and these cancers were more likely to have an emphasized prompt.

CONCLUSIONS

Probably the most important cause of variability of prompts is shifts in film position between sequential digitizations. Consequently subtle lesions that are only just above the threshold for display may not be prompted on repeat scanning. However, users of CAD should be aware that even emphasized prompts are not consistently reproducible.

Functional and economic outcome following microdiscectomy for lumbar disc herniation in 672 patients

A retrospective assessment of 809 patients operated on in 1990-1998 was performed. A patient-based outcome questionnaire also was incorporated into the study. The outcome was graded according to the Functional Economic Rating scale. A total of 64% of the patients were relieved of their complaints 3.2-10.2 years (median 6.3 years) after lumbar disc surgery. An excellent outcome, defined as Prolo scale of 9 or 10, was achieved in 55.8%, a good outcome (Prolo scale 7 or 8) in 20.7%, a fair outcome (Prolo scale 5 or 6) in 11.4%, and a poor outcome (Prolo scale of </=4) in 12.1% of the patients. Patients with strenuous occupations had a significantly (P = 0.004) less favorable outcome than patients with less strenuous or sedentary occupations. Criteria for evaluating the results of treating lumbar spinal disorders vary widely. A more universal acceptance of common criteria for judging the outcome of spinal operations should facilitate comparisons among various methods of treatment.

A comparison of propofol and sevoflurane anaesthesia: effects on aortic blood flow velocity and middle cerebral artery blood flow velocity

We compared systemic (aortic) blood flow and cerebral blood flow velocity in 30 patients randomly allocated to receive either propofol or sevoflurane anaesthesia. Cerebral blood flow velocity (CBFv) was measured in the middle cerebral artery using transcranial Doppler. Systemic blood flow velocity (SBFv) was measured in the aorta using transthoracic Doppler sonography at the level of the aortic valve. Bispectral index (BIS) was used to measure the depth of anaesthesia. Measurements were made in the awake patient and repeated during propofol or sevoflurane anaesthesia, with BIS measurements of 40-50. The effects of SBFv on CBFv were estimated by calculating the cerebral/systemic blood flow velocity-index (CsvI). A CsvI value of 100 indicating a 1 : 1 relationship between CBFv and SBFv. The results demonstrated that propofol anaesthesia produced a significantly greater reduction in CsvI than did sevoflurane anaesthesia [propofol: 60 (19); sevoflurane: 83 (16), p = 0.009, t-test]. This suggests a direct reduction in CBFv independent of SBFv during propofol anaesthesia. The greater reduction of CBFv occurring during propofol anaesthesia may be due to lower cerebral metabolic demand compared with sevoflurane anaesthesia at comparable depths of anaesthesia.

Sociotechnical requirements analysis for clinical systems

OBJECTIVE

We explore sociotechnical requirements by examining the use of a computerized patient record system in an intensive care unit of a U.S. hospital and present two sociotechnical requirements, awareness and coordination, embedded in the users' work.

METHOD

The study is based on observation during seven months of the use of a computerized patient record system in a surgical intensive care unit. During that period semi-formal interviews, informal interviews were held.

RESULTS AND CONCLUSIONS

A key step in the design of clinical systems is the development and analysis of requirements. However, traditional requirements analysis is based on a set of assumptions that break down in the highly collaborative, exception-filled clinical domain. Sociotechnical requirement analysis enabled the designers to gather a much richer description of the environment surrounding the computer system, highlighting awareness and coordination, embedded in the users' work.

Outcome after chronic sciatica as the only reason for lumbar microdiscectomy

There are only a few long-term studies on microsurgical disc operations, and none concentrated on long-term follow-up of therapy-resistant sciatica. A total of 258 patients whose only neurologic symptoms were sciatica were included in this study. Patients were operated on between 1990 and 1997. All outcome results have been performed by an independent reviewer. The mean follow-up period was 7.3 years (range 4-11 years). At follow-up 25% of the patients were free of pain, 66% demonstrated marked improvement, and 9% had either no improvement or worsening of pain. At follow-up 65% of the patients reported returning to their original occupation or being able to go into retirement without hindrance. A total of 15% required changing of profession following discectomy (75% of these patients applying for early retirement were rejected), 6% were incapacitated and unable to work, and 14% were forced into early retirement. Patients with a history of sciatica longer than 3 months acquired failed back surgery syndrome considerably more often than those <3 months (p = 0.005).

Microsurgical anterior cervical foraminotomy (uncoforaminotomy) for unilateral radiculopathy: clinical results of a new technique

BACKGROUND

The authors report the clinical application of a new microsurgical technique. The cervical anterior foraminotomy (uncoforaminotomy), which is used for the surgical treatment of unilateral cervical radiculopathy secondary to posterolateral disc herniations or spondylotic foraminal stenoses.

METHOD

Between June 2000 and May 2001, 34 patients (16 men and 18 women with a mean age of 43.8 years, range 29 to 80 years) underwent anterior cervical foraminotomy (uncoforaminotomy) for the treatment of cervical radiculopathy at one or two adjacent levels in the Neurosurgical Department of the University of Vienna. This surgical technique was devised to accomplish direct anterior decompression of the affected nerve root by removing an offending posterolateral sponylotic spur or disc fragment. The nerve root is decompressed from its origin in the spinal cord to the point were it passes behind the vertebral artery laterally. The intervertebral disc of the affected level is maintained in its form and function. Thus, the functioning motion segment is preserved and fusion related sequelae, including graft related complications, graft site complications and the adjacent level disease, are avoided. Prior to its clinical application, anatomical features of the anterior cervical spine were reviewed, and an anatomical morphometric analysis and work-up of the technique was performed in 4 cervical specimens.

FINDINGS

The follow-up period varied from two to 17 months with a mean of 8.2 months. The large majority (97%) of patients were pleased with the results of their operation. The relief of neck pain and redicular pain in the affected dermatome was immediate in all patients. Motor-weakness and sensory deficit improved dramatically immediately postoperatively, and improved to normalisation in the majority of patients within 3 to 6 months. Two of the patients sustained an incomplete transient recurrent laryngeal nerve palsy, which fully resolved within two to 4 weeks. One of the patients had a repeat herniation on the second postoperative day, but recovered completely after re-operation and continued to do well at the 6-month follow-up. No permanent surgery related morbidity or associated complications were encountered.

INTERPRETATION

The results indicate that this new microsurgical technique is an attractive treatment option for adequate anterior decompression of the cervical nerve root via a minimized approach. It was associated with excellent clinical outcome and a less painful postoperative course, allowing patients an almost immediate return to unrestricted full activity.

Neurological outcome following laminectomy in spinal metastases

STUDY DESIGN

Retrospective outcome measurement study.

OBJECTIVES

Patients suffering from malignant tumour disease and metastases to the spine develop a variety of clinical complaints including radicular symptoms and/or spinal cord compression syndromes. Palliative decompressive laminectomy with total or partial tumour resection is an acknowledged method of treatment, despite controversy.

SETTING

The Department of Neurosurgery of the University of Vienna.

METHOD

Patients suffering from metastases with predominant infiltration of the dorsal epidural parts, or patients who could not be operated on via an anterior approach, were included. Eighty-four patients who met these criteria underwent decompressive laminectomy with total or partial tumour removal. The study analyzed motor function, pain relief and continence in a 2- and 4-month post-operative follow-up. According to the criteria of motor performance, 20% of the patients had been mobile pre-operatively.

RESULTS

In the immediate post-operative period 45%, after 2 months 33% and after 4 months 26%, were considered mobile. None of the paraplegic patients showed functional improvement. The median survival time was 6.5 months. Pre-operatively, 56% of the patients had shown continence dysfunction. Post-operatively, 38%, and after 2 months 46% of the patients, developed continence disorders. A significant reduction in analgesic medication was also observed in the post-operative period.

CONCLUSION

In our series, palliative laminectomy with total or subtotal tumour reduction in patients with malignant spinal metastatic disease resulted in amelioration of motor function, pain and continence and therefore improved the patients' quality of life. The improvement in quality of life shows that this method is a valuable option in neurosurgical therapy, except for cases with pre-operative paraplegia. However, in patients with severe pre-operative paraparesis, the authors recommend laminectomy only in very exceptional cases, because of the poor post-operative neurological results.

The complexity of trauma to the cranio-cervical junction: correlation of clinical presentation with Doppler flow velocities in the V3-segment of the vertebral arteries

BACKGROUND

Trauma to the craniocervical junction (CCJ) encompasses a wide and complex spectrum of injury with an even broader range of clinical presentation, and since trauma to this area borderlines neurosurgical main areas of interest, these relatively rare injuries can be overlooked. In fact, there has been an abundance of documentation in the literature since Sir Charles Bell first reported on a case of occipital condyle fracture in 1817 in which a patient suddenly dropped dead as he turned his head to thank physicians and nurses while leaving the hospital. The death was attributed to compression of the medulla oblongata by a fractured occipital condyle.

METHOD

At our department, we have been applying specialized diagnostic procedures in our clinical work-up in the acute and chronic situation of isolated injury to the CCJ as well as polytrauma with CCJ involvement in a total of 33 patients throughout a 3-year period (1997 to 2000). In this article, we present some of our experiences with these diagnostic procedures, introducing the application of V3-segment Doppler of the vertebral artery (VA), which we consider to be an effective supplementary method in a precise work-up in CCJ injury. The V3-segment of the vertebral artery, especially where it courses through its' groove behind the superior facet of the atlas is particularly vulnerable to injury. The authors measured flow velocity of the V3-segment from a point just below and roughly 2 to 3 centimeters dorsal to the mastoid process.

FINDINGS

All patients were investigated for the occurrence of changes in the blood flow in the V3-segment of the VA after suffering a CCJ injury. There was an increase or decrease in the flow velocity in trauma patients with whiplash injuries as well as in patients with occipital condyle fractures and associated ligament injury. In severe injuries, some with fatal outcome, a dissection or thrombosis of the VA was found with a loss of the V3-doppler flow signal, or rather flow void.

CONCLUSION

CCJ injuries in the polytrauma patient as well as in patients presenting with delayed onset of symptoms often remain unrecognised, despite the advances in medicine. CCJ injuries are potentially lethal and can be treated if detected early. The V3 method enables rapid, effective, feasible and inexpensive diagnosis in the initial work-up of CCJ-injury.

Stereotactic radiosurgery for brain metastases from colorectal cancer

PURPOSE

The development of brain metastases represents an ominous event for patients with colorectal cancer. We evaluated results following stereotactic radiosurgery (SR) for patients with metastatic colorectal cancer to identify efficacy of SR and prognostic factors for survival.

METHODS

This is a retrospective study of 60 brain metastases from colorectal cancer in 35 consecutive patients who underwent SR from January 1993 to December 1996. Thirteen patients also underwent additional whole-brain radiation therapy (WBRT). The median dose delivered to the tumor margin was 20 Gray (range 16-28 Gy), in most cases the tumor enclosing the 50% isodose (range 40-60%). Patients were classified into two groups: SR with and SR without WBRT. Univariate and multivariate testing was performed to determine significant prognostic factors.

RESULTS

The median survival time was 6 months after SR and 40 months after diagnosis of primary tumor. A Karnofsky performance scale >70 was a significantly favorable prognostic factor in uni- and multivariate testing. Post-SR imaging was evaluated in 32 patients and in 54 cerebral lesions. Local tumor control was revealed in 94% of patients and 96% of treated tumors. Two patients developed local recurrences, and remote brain disease was revealed in five. No patient experienced a new focal neurologic deficit due to SR. The addition of WBRT to SR did not improve survival and local tumor control rates. Distant control rate was borderline in univariate analysis and significantly improved for patients who received additional WBRT in multivariate analysis.

CONCLUSION

SR for brain metastases from colorectal cancer results in a high local tumor control rate of 94% associated with few complications and therefore provides patients with a higher quality of their remaining life.

A clinical study of a fibrinogen-based collagen fleece for dural repair in neurosurgery

BACKGROUND

There is frequently a need for dural grafts to cover defects resulting from retraction, shrinkage, or excision following neurosurgical procedures. Many substances have been tried as possible dural substitution, and different tissues and materials have been evaluated for use in dural repair.

METHOD

The authors performed a retrospective review of 288 consecutive neurosurgical procedures using a fibrinogen based collagen fleece (TachoComb), a resorbable mesh of collagen from horse tendons, coated with human fibrinogen, bovine thrombin, bovine aprotinin and riboflavin (for marking the coated side), for dural substitution. The fibrinogen and thrombin imitate the last step of the coagulation cascade. On contact with bleeding wounds or other body fluids the coagulation factors dissolve and a link is formed between the collagen carrier and the wound surface. Thrombin converts fibrinogen into fibrin by splitting off peptides. Aprotinin prevents premature lysis of the fibrin clot by plasmin.

FINDINGS

Neither superficial or deep wound infections nor aseptic meningitis were noted. We found good fibrous incorporation of TachoComb into the surrounding normal dura. Postoperative cerebrospinal-fluid (CSF) leaks developed in only five cases, who had to be re-operated, upon as well as one patient with a rebleeding. In another four cases, there was notable subcutaneous cerebrospinal-fluid accumulation without CSF-leak. They required a lumbar cerebrospinal-fluid drainage.

INTERPRETATION

We conclude that TachoComb is a valuable alternative to the patients fibrous tissues for dural repair in cases in which autogenous tissues are either unavailable or insufficient for proper reconstruction.

Transmission of penile cuff pressure to the penile urethra

PURPOSE

We developed a noninvasive method to measure voiding bladder pressure by inflating a penile cuff to interrupt flow. We tested the underlying assumption that cuff pressure is transmitted to the penile urethra.

MATERIALS AND METHODS

In 35 men we simultaneously recorded penile cuff and urethral pressure during 2 experimental protocols for 6 cuffs of various widths and manufactures. Initially a urethral pressure transducer was placed at the mid point of the cuff and urethral pressure was continuously recorded during cuff inflation. In experiment 2 cuff pressure was set at 120 cm. water and the urethral pressure profile was measured by withdrawing the urethral transducer through the cuff width.

RESULTS

There was excellent agreement of cuff with urethral pressure over the range of 0 to 200 cm. water for cuffs 37 to 54 mm. wide. Narrower cuffs showed wider variation with less efficient transmission of cuff pressure to the urethral lumen. Similarly maximum pressure in the urethral pressure profile showed best agreement for cuffs 38 and 46 mm. wide. Wider cuffs produced higher and narrower cuffs produced lower transmitted pressure within the urethra. Cuff performance was also related to penile size. Results had good within-subject repeatability.

CONCLUSIONS

We demonstrated that pressure transmission from cuff to urethra is optimal at a cuff width of 40 to 50 mm. and recommended this width for other investigations of noninvasive bladder pressure measurement.

IS186 insertion at a hot spot in the lon promoter as a basis for lon protease deficiency of Escherichia coli B: identification of a consensus target sequence for IS186 transposition

The radiation sensitivity of Escherichia coli B was first described more than 50 years ago, and the genetic locus responsible for the trait was subsequently identified as lon (encoding Lon protease). We now show that both E. coli B and the first reported E. coli K-12 lon mutant, AB1899, carry IS186 insertions in opposite orientations at a single site in the lon promoter region and that this site represents a natural hot spot for transposition of the insertion sequence (IS) element. Our analysis of deposited sequence data for a number of other IS186 insertion sites permitted the deductions that (i) the consensus target site sequence for IS186 transposition is 5'-(G)(> or =4)(N)(3-6)(C)(> or =4)-3', (ii) the associated host sequence duplication varies within the range of 6 to 12 bp and encompasses the N(3-6) sequence, and (iii) in a majority of instances, at least one end of the duplication is at the G-N (or N-C) junction. IS186-related sequences were absent in closely related bacterium Salmonella enterica serovar Typhimurium, indicating that this IS element is a recent acquisition in the evolutionary history of E. coli.

AtHKT1 is a salt tolerance determinant that controls Na(+) entry into plant roots

Two Arabidopsis thaliana extragenic mutations that suppress NaCl hypersensitivity of the sos3-1 mutant were identified in a screen of a T-DNA insertion population in the genetic background of Col-0 gl1 sos3-1. Analysis of the genome sequence in the region flanking the T-DNA left border indicated that sos3-1 hkt1-1 and sos3-1 hkt1-2 plants have allelic mutations in AtHKT1. AtHKT1 mRNA is more abundant in roots than shoots of wild-type plants but is not detected in plants of either mutant, indicating that this gene is inactivated by the mutations. hkt1-1 and hkt1-2 mutations can suppress to an equivalent extent the Na(+) sensitivity of sos3-1 seedlings and reduce the intracellular accumulation of this cytotoxic ion. Moreover, sos3-1 hkt1-1 and sos3-1 hkt1-2 seedlings are able to maintain [K(+)](int) in medium supplemented with NaCl and exhibit a substantially higher intracellular ratio of K(+)/Na(+) than the sos3-1 mutant. Furthermore, the hkt1 mutations abrogate the growth inhibition of the sos3-1 mutant that is caused by K(+) deficiency on culture medium with low Ca(2+) (0.15 mM) and <200 microM K(+). Interestingly, the capacity of hkt1 mutations to suppress the Na(+) hypersensitivity of the sos3-1 mutant is reduced substantially when seedlings are grown in medium with low Ca(2+) (0.15 mM). These results indicate that AtHKT1 is a salt tolerance determinant that controls Na(+) entry and high affinity K(+) uptake. The hkt1 mutations have revealed the existence of another Na(+) influx system(s) whose activity is reduced by high [Ca(2+)](ext).

CD4 mAb induced apoptosis of peripheral T cells: multiparameter subpopulation analysis by flow cytometry using Attractors

Studies describing the induction of apoptosis for CD4 mAbs do not delineate between epitope-dependent and Fc-driven epitope cross-linking induced cell death. Keliximab and clenoliximab are two CD4 mAbs that differ only in their heavy chain isotypes, being an IgG1 and a modified IgG4, respectively. These antibodies suppress CD4 T cell responses in vitro and in vivo and have been in human clinical trials for the treatment of RA and asthma. Here we compared the apoptotic activity of these mAbs to differentiate between the contributions of epitope-dependent vs. Fc-driven epitope cross-linking induced cell death in vitro as a link to differential CD4 cell depletion in vivo. We developed a simple flow cytometry procedure that measures apoptosis within intact and compromised subpopulations of PBMCs within a few hours of culture. Attractors software was used to quantitate the percentage of apoptotic CD4 T cells, which generate reactive oxygen species (ROS), express external phosphatidyl serine (PS) and cleaved fluorescein diacetate (FDA), within the intact and compromised lymphocyte populations. Treatment of freshly isolated PBMCs with keliximab resulted in the appearance of characteristic apoptotic condensed CD4 T cells that contained reactive oxygen species, were annexin V positive and had intact esterase activity. Apoptosis was evident within 3 h and continued throughout the 72-h culture period. In contrast, clenoliximab alone did not induce apoptosis. The use of multiparameter flow cytometry and Attractors to analyze subpopulations based on scatter properties and biochemical processes during apoptosis provides a sensitive assay in which to quantitate and characterize the induction of cell death. Depletion of CD4 T cells in vivo by keliximab may reflect, in part, antibody-mediated apoptosis of these cells that is dependent on Fcgamma receptors.

Neonatal repair of truncus arteriosus: continuing improvement in outcomes

BACKGROUND

Repair of truncus arteriosus in the neonatal and early infant periods has become standard practice at many centers. We reviewed our recent experience with repair of truncus arteriosus in neonates, with a focus on early and intermediate outcomes.

METHODS

From July 1992 to December 1999, 65 patients 1 month of age or less underwent primary complete repair of truncus arteriosus. Median age was 10 days, and median weight was 3.2 kg. Major associated anomalies included moderate or severe truncal valve regurgitation in 15 patients (23%), interrupted aortic arch in 8 (12%), coronary artery abnormalities in 12 (18%), and nonconfluence of the pulmonary arteries in 3 (5%). Median durations of cardiopulmonary bypass and cardioplegic arrest were 172 minutes and 90 minutes, respectively. Circulatory arrest was employed only in 7 patients undergoing concomitant repair of interrupted arch. Reconstruction of the right ventricular outflow tract was achieved with an aortic (n = 39) or pulmonary (n = 26) allograft valved conduit (median diameter, 12 mm). Replacement (n = 6) or repair (n = 5) of a regurgitant truncal valve was performed in 11 patients, and interrupted arch was repaired in 8.

RESULTS

There were three early deaths (5%). Early reoperations included reexploration for bleeding in 3 patients, emergent replacement of a pulmonary outflow conduit that failed acutely in 1 patient, and placement of a permanent pacemaker in 1. Mechanical circulatory support was required in 1 patient. During the median follow-up of 32 months, there were two deaths. The Kaplan-Meier estimate of survival was 92% at 1 year and beyond. The only demographic, diagnostic, or operative factors significantly associated with poorer survival over time were operative weight of 2.5 kg or less (p = 0.01) and truncal valve replacement (p = 0.009). Actuarial freedom from conduit replacement among early survivors was 57% at 3 years.

CONCLUSIONS

Repair of truncus arteriosus in the neonatal period can be performed routinely with excellent survival, even in patients with major associated abnormalities.

A lateral mass fracture of C1 associated with left vertebral artery and mid-basilar artery occlusion

Extreme acceleration and deceleration forces as well as axial loading are exerted at the occipito-cervical junction of drivers involved in high-velocity motor vehicle accidents, especially with fastened seatbelts. Injury at this level, usually lethal, can go unrecognized despite modern emergency management of the unconscious patient. A precise neurologic and radiographic workup of damage to this area is often not possible or overlooked in the initial phase of such severe trauma. We describe a patient with multiple injuries who sustained a left vertebral artery occlusion associated with a left-sided lateral mass fracture of C1 and a basilar artery occlusion resulting in a locked-in syndrome after an automobile accident.

Solvation effect on organic compound interactions in soil organic matter

We examine sorption of pyridine by soil organic matter (SOM) from different organic media including n-hexadecane, acetonitrile, acetone, and n-hexadecane mixtures with either acetonitrile or acetone and compare it with sorption from water. By using an activity-based comparison, we distinguish between solvent-assisted and solvent-competitive sorption behavior. Pyridine was selected because it forms strong complexes with phenolic and carboxylic groups, such that site interactions should dominate interactions in SOM. It is anticipated that pyridine sorption will be illustrative of the importance of disrupting strong interactions in a condensed, shrunken SOM phase for many organic compounds. It was generally found that activity-normalized pyridine uptake was assisted by polar solvent molecules rather than suppressed due to competition. An explanation is tendered on the basis of our earlier hypothesis of water-assisted disruption of polar SOM contacts. Certain polar moieties of dry SOM are unavailable for compound sorption due to strong interactions between them. By penetrating SOM structure, solvent molecules (and water) solvate (hydrate) polar moieties creating new sorption sites. Solvent molecules must solvate both moieties of the polar contact, such that the driving force for solvent-assisted sorption is solvation of the partner of the disrupted contact that does not directly interact with the sorbate.

Implants in regenerated bone in a primate model

BACKGROUND

Earlier publications from our laboratory described the use of guided bone regeneration to fill large bone voids in the mandible created through en bloc resection in primates. The present report describes placement of implants into the regenerated bone with subsequent prostheses construction and loading.

METHODS

Lesions were created in the mandibles of 9 monkeys in a standardized mandibular defect of 8 x 19 mm. Reinforced expanded polytetrafluoroethylene membranes were placed in the animals and held in place with mini screws and sutures for anywhere from 1 to 12 months. No material was added to the defect. In each animal a root-form implant was placed 12 mm distal to the abutment teeth into the regenerated bone and was loaded with a prosthesis for 12 months. These implants were compared to original implants placed in the same monkeys years earlier in the same location in non-regenerated bone. Digital radiology and histomorphometry are described.

RESULTS

The results show that root-form implants placed in regenerated bone show the same radiological and histomorphometric characteristics as in normal bone when loaded. In addition, the percentage of bone contact with implants seen in regenerated bone versus non-regenerated bone is the same when both are loaded (65 +/- 13% SD in regenerated bone versus 59 +/- 15% SD in non-regenerated bone).

CONCLUSIONS

In a primate model root-form implants placed in regenerated bone and prosthetically loaded show no difference when compared to root-form implants placed in non-regenerated bone and prosthetically loaded.