Rehabilitation outcome 5 years after 100 lower-limb amputations

Received wisdom commends a policy of maximizing the ratio of below-knee to above-knee amputations in patients with end-stage arterial disease. After adoption of this policy, the long-term outcome of 100 consecutive lower-limb amputations in 96 patients was monitored by annual review for 5 years. The ratio of primary below-knee to above-knee amputations was 2:1, with 9 per cent of below-knee amputations undergoing revision to a higher level. At 2 years after amputation only 26 per cent of patients were successfully walking out of doors, while 40 per cent had died. By 5 years 67 per cent were dead and only 9 per cent continued to walk out of doors with an artificial limb, although a further 8 per cent continued to use the limb within the confines of their own homes. In a previous audit of 193 amputations performed during the 3.5 years to December 1984, stump healing was a problem in 45 per cent of primary below-knee amputations, compared with 25 per cent in the present study. Although the below- to above-knee ratio in 1984 was only 1:2, the overall rehabilitation rate, as determined by the proportion of patients able to walk at 2 years, was 34 per cent. It is concluded that increasing the proportion of below-knee amputations from one-third to two-thirds of lower-limb amputations for occlusive arterial disease does not improve effective rehabilitation rates. Received wisdom on the desirability of a high below- to above-knee ratio may be wrong.

Effects of fit and bonding characteristics of femoral stems on adaptive bone remodeling

Bone atrophy caused by stress-shielding may cause serious complications for the long-term fixation of hip stems. In particular, uncemented total hip arthroplasty is threatened by this problem, because the stems are usually larger and, as a consequence, stiffer than those of cemented implants. In the present study, the effects of fit and bonding characteristics of femoral hip stems were investigated, using the (nonlinear) finite element method in combination with adaptive bone remodeling theory to predict the bone density distribution in a bone or bone/implant configuration. Unknown parameters used in the theory, such as a reference equilibrium loading stimulus and a threshold (dead) zone of this stimulus, were established (triggered) by using the method to predict the density distributions in the natural femur and around fully coated uncemented implants. The computer simulation method can provide long term predictions of remodeling patterns around various implant configurations. Several cases were analyzed, whereby the coating conditions (fully, partly, or noncoated) and the fit characteristics (press fitted or overreamed) were varied. The computer predictions showed that partly coating can only significantly reduce bone atrophy relative to fully coated stems, when the coating is applied at a small region at the utmost proximal part of the stem. For smooth press-fit stems the predicted amount of bone loss (35 percent in the proximal medial region) was less than for a one-third proximally coated or a fully coated stem (50 to 54 percent predicted bone loss in the proximal medial region).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of Ca/P coating resorption and surgical fit on the bone/implant interface

The effect of coating resorption on bone apposition and attachment strength to resorbable hydroxyapatite (HA), nonresorbable HA-coated, and uncoated rough titanium implants was evaluated in interference- and noninterference-fit (gap of 2-3 mm) surgical models 2, 4, and 12 weeks postoperatively. Interference and noninterference fits showed differences in bone bridging. Bone apposition was circumferential around the implants in noninterference fit. Significantly greater bone apposition was seen to nonresorbable HA-coated implants than uncoated and resorbable HA-coated implants at 4 and 12 weeks. Only resorbable HA coatings showed significantly lower bone apposition for noninterference versus interference fit and from 4-12 weeks. At 2 weeks, strengths of bone attachment to resorbable HA-coated implants were greater than the other implants, and decreased to lower values (not significant) than the nonresorbable HA-coated implants at 4 and 12 weeks. Differences in push-out shear strengths between interference- and noninterference-fit surgical models were significant for uncoated implants at 4 weeks, but not for HA-coated implants at any time period. Significant differences were seen between the three implant types only for the noninterference-fit model, where the HA-coated implants showed greater strengths than the uncoated implants (significant at 2 and 4 weeks). This study showed that presence of resorbable or nonresorbable HA coatings is beneficial when a gap of 2-3 mm is present between the implant and the bone. The resorbable HA-coated implants showed greatest strengths at the early time period. At later time periods, resorbable HA-coated implants showed lower bone apposition and attachment strengths than nonresorbable HA coatings.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer-stimulated test fitting of an implantable hearing aid using implantable hearing aid using three-dimensional CT scans of the temporal bone: preliminary study

In preparation for future implantation of the implantable middle ear transducer in patients, a method was sought for preoperatively test fitting a model of the device, using computer generated three-dimensional (3-D) temporal bone images derived from spiral computed tomography (CT) data. A 3-D model of the implantable middle ear transducer was designed using NIH Image software on a Macintosh computer. High resolution human temporal bone CT scans were obtained using a spiral CT scanner (Siemens Somatom Plus S). The 3-D transducer model was superimposed onto 3-D reconstructions of the temporal bone using ANALYZE software on a computer graphics workstation (Sun SPARCstation 10), showing the transducer "implanted" in the temporal bone. Measurements were validated using a cadaver temporal bone. This process produced images demonstrating the "fit" of the current transducer design in the mastoid region of the adult temporal bone. It permitted assessment of the proximity of surrounding structures such as the external auditory meatus, dura, or sigmoid sinus. Preliminary cadaver validation measurements confirmed the accuracy of this method. Three-dimensional CT is a feasible method for preoperative planning of the surgical implantation of devices in the temporal bone. This method of 3-D test fitting will be used in the future to determine optimum orientation and size limitations for human implantable devices.

Check records--a chairside mounting procedure

This article considers the logistical problems involved when the check (interocclusal) record procedure is used to remount complete dentures on an articulator. It reports the development of upper and lower "check record mounting blocks" that may be made to fit any articulator, thus enabling the procedure to be performed easily and quickly at chairside.

Myoelectric prostheses in the management of Poland's syndrome. A report of 2 cases

Two cases of Poland's syndrome are reported in whom myoelectric prostheses have been used. The rare congenital sporadic disorder of Poland's syndrome characterized by absence of pectoralis major and varying degrees of ipsilateral upper limb deficiency has been reported by various authors (Rasjad and Sutiaksa, 1991, Gausewitz et al, 1984; David, 1982; Ireland et al, 1976). Management of the upper limb deficiency depends on the degree of functional and cosmetic disability. We report two cases of Poland's syndrome where myoelectric prostheses have been successfully used. We have been unable to find any published report of the use of a myoelectric prosthesis in Poland's syndrome.

A new method to routinely achieve passive fit of ceramometal prostheses over Brånemark osseointegrated implants: a two-year report

To maintain osseointegration, it is essential that the prosthesis fit with total passivity because the absence of a periodontal ligament makes the implant unable to adapt its position to a nonpassive framework. The traditional system of building a metal framework by melting over mechanized pieces--called gold cylinders in the Brånemark system--has been modified so these pieces are joined to the metal framework by means of physicochemical bonding. This bond is achieved by treating the metallic surfaces with a Silicoater system and a composite resin cement that sets in the mouth using an improved cementing protocol. In this paper, the clinical viability of this new philosophy, shown over 2 years, is presented. A total of 64 prostheses (39 maxillary and 25 mandibular) supported by 214 abutments, with an average observation period of 9 months, were evaluated. The results show that it is possible to routinely obtain a ceramometal prosthesis with a totally passive circular fitting while maintaining the possibility of retrieval, thus making postceramic soldering unnecessary.

Rheumatoid nodules on amputation stumps: report of three cases

We describe three patients, all of them lower limb amputees who also had seropositive, nodular rheumatoid arthritis. In each case, rheumatoid nodules developed on the amputation stump, causing difficulties with prosthesis fit and comfort and impairment of ambulation. Nodules were successfully excised in two cases and the prosthesis modified in the third. The patients were able to resume walking or transferring with their prostheses.

The long-term use of the SoftPerm lens on pellucid marginal corneal degeneration

Pellucid marginal corneal degeneration (PMCD) is a corneal degeneration often confused with keratoconus because of the presence of high regular and irregular astigmatism. Vision correction can be achieved with rigid contact lenses, but the asymmetric topographic profile often makes obtaining a stable lens fit difficult. This study describes the fitting and satisfactory daily wear during 4 years of a combination lens design (2 years Saturn II and 2 years SoftPerm) on a patient with PMCD. The lens consisted of a central rigid gas permeable portion surrounded by a soft hydrophilic "skirt." Although the degree of astigmatism was high, 1.6 mm (8.00 D) by keratometry and 12.00 D by refraction, the patient was able to wear the lens comfortably 12 hours per day and achieve visual acuity of 20/20. Routine keratometry, pachymetry, and slit lamp examination showed no significant corneal changes resulting from lens wear.

Silicone rubber contact lenses for the compromised cornea

Silicone rubber contact lenses (SRCLs) are infrequently used because of the risk of developing unpredictable lens tightening, their poor availability, and their expense. However, their high oxygen transmissibility and nonabsorption of water make them valuable as therapeutic lenses. SRCLs are routinely used in our management of severely dry eyes, decompensated or vascularised corneas, and conditions where the corneal shape is flat or irregular. The records of 48 consecutive patients fitted with SRCLs between January 1989 and June 1990 were studied. The clinical history, indications, complications, success, and duration of SRCL wear were analysed. Therapeutic goals, which included epithelial healing, sealing of corneal perforations, and improved comfort and vision, were achieved in 53 of 62 eyes. The best corrected acuity was attained using SRCLs in 58 of 62 eyes. Failure of lens wear was due to lens tightening (four eyes), spoilation (two), discomfort, fornix shortening, handling problems, and decentration (one each). Infective keratitis complicated one case, but SRCL wear was resumed after successful treatment. With adequate follow-up, SRCLs have a low complication rate and are well tolerated even in severely compromised eyes, for which conventional lenses may be contraindicated. Their continued use as therapeutic lenses is advocated in carefully selected cases.

Blink-induced variations in visual performance with toric soft contact lenses

BACKGROUND

Blink-induced lens movement causes a reduction in visual performance that is potentially greater with toric than with spherical soft contact lenses because of the combination of vertical lens movement and rotation. This study examined the effect of the two most common methods of toric lens stabilization (prism ballast and dynamic stabilization) on vision.

METHOD

Four toric soft contact lens wearers were the subjects (astigmatic range 1.25 to 2.25 D). Stimulus presentation (10.5 cpd sine wave grafting flashed for 16 ms) occurred at specified times up to 400 ms after the blink. Contrast thresholds were determined monocularly with spectacles and the two types of contact lenses.

RESULTS

For the grouped data, the prism balasted lens gave better overall visual performance than the dynamic stabilization at all times after the blink. Separate analysis of subject data suggested that this general pattern was not true for all individuals.

CONCLUSIONS

Clinical evaluation of different lens designs on individual patients is required for achieving the optimum visual performance with toric soft lenses.

Ultrasound biomicroscopy for the assessment of Molteno tube position

Due to anatomic distortion or surgical complications, it may be difficult to determine the precise position of an implanted Molteno tube. We performed ultrasound biomicroscopy (high-resolution ultrasound) to test the usefulness of this modality in localizing implanted Molteno tubes in 10 patients with Molteno tubes. A 50-megahertz transducer with a penetration of approximately 4 mm was used to produce a magnified image of the anterior segment. The Molteno tube was visualized without complication in all of these cases.

Reconstructive amputation after grade IIIC open tibial fracture. One method of preserving residual limb length

A high percentage of patients with grade IIIC open tibial fractures eventually undergo amputation. Maintaining an adequate residual limb length is advantageous with regard to biomechanics, energy expenditure, and prosthetic fitting. This case report presents new considerations for maintaining residual limb length in the presence of comminuted proximal tibial fractures. These considerations include (a) using an autogenous fibular strut graft for stabilizing the reconstructed residual limb and (b) determining the level of amputation based on soft-tissue integrity rather than on fracture level. We present one technique for preserving an adequate residual limb length in the face of significant proximal tibia comminution.

Bitoric rigid contact lens with prism fitting in rare cases of moderate corneal and residual astigmatism

We reviewed all records of bitoric rigid gas permeable (RGP) contact lenses with prism ballast fittings performed at Tulane University Hospital and affiliated clinics from 1985 to 1993. We found eight eyes of six patients fit were fit with this lens, which is indicated for the patient with a moderately astigmatic cornea in addition to residual refractive astigmatism. In this design, a small amount of prism is added to a standard bitoric design to achieve rotational stability. All patients achieved 20/25 or better vision. We provide an outline for fitting bitoric RGP contact lenses with prism ballast.

Passive fit of implant-retained prosthetic superstructures improved by electric discharge machining

PURPOSE

An absolutely passive fit at the interface with the superstructure and the abutment cylinders is needed for implant longevity. In this study, a method of cast framework correction using electric discharge machining (EDM) was evaluated.

MATERIALS AND METHODS

An original research model incorporating strain gages was devised to measure the fit of implant superstructures in three dimensions as cast and to compare this relationship with the fit following framework machining with EDM.

RESULTS

Visually, the fit of the frameworks was excellent, and the results of ANOVA demonstrated that the mean fit of the frameworks significantly improved (P > .04) after machining with EDM.

CONCLUSIONS

The EDM process offers a rapid, accurate, and simple technique to correct for casting inaccuracies in the fabrication of hybrid implant prostheses.

Effect of prescribed prism on monocular interpupillary distances and fitting heights for progressive add lenses

Success in fitting progressive addition lenses is dependent upon the accurate placement of the progressive zone. Both eyes must track simultaneously within the boundary of the progressive corridor. Vertical prism will displace the wearer's lines of sight and consequently eye position. Because fitting heights are measured using an empty frame, subjects with vertical phorias usually will fuse, and not show the vertical differences in pupil heights during the measuring process. Therefore, when prescriptions contain vertical prism one must consider the changes in measured fitting heights that will occur once the lenses are placed in the frame. Fitting heights must be altered approximately 0.3 mm for each vertical prism diopter prescribed. The fitting height adjustment is opposite from the base direction of the prescribed prism. An explanation of the effect of prescribed horizontal prism on monocular interpupillary distance (PD) measurements is also included.

Soft lens movement: temporal characteristics

The time-course of on-eye hydrogel lens movement has not been carefully scrutinized, despite the importance of lens movement in optimizing lens fit and corneal physiology. We conducted a study to define the time-course of soft lens movement using 26 subjects. Video slitlamp recordings were made of lens movement at 5-min intervals for 30-min wear and after 8-h wear of 38 or 67% water content lenses (N = 14 and 12, respectively). Lens mobility profiles were statistically indistinguishable for high and low water content lenses, and for experienced and neophyte lens wearers. Lens movement displayed biphasic temporal characteristics, decreasing significantly over the first 25 min from a median of 0.6 to 0.3 mm (Wilcoxon matched-pairs signed-rank test, p = 0.002), then increasing significantly to 0.5 mm after 8 h of wear (p = 0.03). Although some subjects exhibited little alteration in lens movement, 31% showed a decrease in lens movement > 0.25 mm during the first half-hour of wear. Optimal predictability of lens mobility after 8-h wear was achieved 5 min after insertion, with 77% of subjects displaying lens movement within +/- 0.25 mm of the final value. In-office assessment of lens movement is best achieved 5 min after insertion, although clinical and real world lens mobility will differ significantly in about one in four patients.

The relationship between the design, position, and articular wear of acetabular components inserted without cement and the development of pelvic osteolysis

Between 1983 and 1987, an acetabular component with a unique chamfered-cylinder design was inserted without cement in 134 hips. With use of this design, initial stability is achieved through a cylindrical interference fit with the peripheral rim of the acetabulum, without the need for pegs, spikes, or screws. At an average of sixty-four months (range, forty to ninety-six months) after implantation, follow-up data were available for 113 hips (ninety-three patients). No component had been revised for loosening or was radiographically loose. However, the prevalence of balloon-like osteolysis of the pelvis was 17 per cent (nineteen hips). This bone loss was generally not associated with pain or other symptoms. Ten of the nineteen hips that were associated with pelvic osteolysis (including six of the nine that were associated with osteolysis of the ilium) had been reconstructed with use of an acetabular component that had no holes in the shell (that is, the shell was completely solid). This finding indicates that, while elimination of holes through the acetabular shell may have advantages, it will not prevent pelvic osteolysis. The osteolysis of the ilium was associated with a lateral opening of the acetabular component of more than 50 degrees (p < 0.0001). All of the hips in this series had insertion of a porous-ingrowth femoral resurfacing component made of titanium alloy. These components are no longer used. Revision of the femoral side due to osteolysis provided a unique opportunity to inspect directly forty-two clinically well functioning acetabular components. All of the polyethylene liners and acetabular shells were found to be rigidly fixed. Inflammatory tissue at the periphery of the implant-bone interface resulted in circumferential resorption of periacetabular bone despite rigid fixation of the component. This is direct evidence that a process of bone resorption similar to that reported at the cement-bone interface of cemented acetabular components can occur at the implant-bone interface of components inserted without cement. At the reoperation, a communication that had led to the pelvic osteolysis was found through areas of bone resorption at the periphery of the implant-bone interface. These areas were essentially cystic and were filled with a mixture of fluid and friable, yellow-tan tissue. It appeared that the osteolytic process had expanded into the soft cancellous bone and marrow while being contained by the denser cortical shell of the pelvic bones.(ABSTRACT TRUNCATED AT 250 WORDS)

The optometry game: enhancing test selection and lens prescribing skills by use of computer simulations

The Optometry Game is a computer simulation developed to aid students in practicing test selection and lens prescription skills. Features of the simulation include a game format, digitally reproduced voices and patient pictures, and the ability of the user to customize the game for a variety of applications. Twenty optometry students evaluated the game by playing a variety of simulated patients and found it to be potentially useful in various classroom learning environments.

Shear bond strength of resin bonded ceramic after different try-in procedures

Final cementation of porcelain laminate veneers may require a previous colour match try-in. The purpose of this in vitro study was to evaluate the effect on shear bond strength of resin bonded to porcelain after the application of different try-in procedures. Forty porcelain specimens were fabricated, flattened with 600 grit SiC, etched with hydrofluoric acid and silane treated. After 24 h the specimens were divided into four groups at random and prior to bonding of a dual cure resin composite button were treated as follows: Group 1, no treatment (control); Group 2, non-activated resin applied for 5 min, cleaned in acetone for 3 min; Group 3, as for Group 2, with silane reapplied; Group 4, as for group 3, but re-etched for 30 s before reapplication of silane. After bonding the specimens were stored in water at room temperature for 7 days. Shear bond strength data were as follows: Group 1, 18.6 +/- 1.6; Group 2, 15.9 +/- 1.7; Group 3, 16.7 +/- 2.6; Group 4, 15.3 +/- 3.0 MPa. Fractured surfaces examined, under light microscopy and scanning electron microscopy (SEM), showed cohesive failure within the porcelain in all cases. The reduction in mean bond strength after application of a try-in resin was significant in Groups 2 and 4 compared with the control (ANOVA P < 0.05). No other significant differences were measured. In conclusion a single reapplication of silane maintained the bond strength of resin to porcelain when final cementation was preceded by a try-in procedure and cleaning.

A quantitative in vitro assessment of fit and screw fixation on the stability of a cementless hemispherical acetabular component

This investigation quantifies in vitro the effect of component fit, as well as the effect of adjuvant screw fixation, on the initial stability of cementless hemispherical titanium acetabular total hip arthroplasty components and assesses apposition of the acetabular components to bone. Six, fresh human hemipelvi (3 matched pairs) were harvested at autopsy. Titanium alloy acetabular components with a porous surface of commercially pure titanium fiber mesh (Harris Galante Porous acetabular components, Zimmer, Warsaw, IN) were used for implantation. Initially, each acetabulum was underreamed to achieve a 2 mm press-fit with the acetabular component. Pressure-sensitive film had been placed along the dome and medial wall at the bone-implant interface to assess the completeness of seating. After the implant was impacted into the acetabular cavity, relative motion between the implant and bone was measured during simulated single leg stance. Adjuvant fixation of the implant was then obtained with the insertion of four 6.5 mm cancellous screws. High-contrast roentgenograms of the specimens in multiple views were obtained after initial cup insertion and again after screw insertion. The stability of each implant under load was measured with four, three, two, one, and no screws in place. Further reaming of the bone was done to create a 1 mm press-fit. The sequence was then repeated. Further reaming was done to create an exact-fit and the sequence was repeated again. Under these conditions, 1 mm press-fit with or without screws provided the optimum combination of fit stability.(ABSTRACT TRUNCATED AT 250 WORDS)

Contact lenses in the geriatric patient

Contact lenses in the elderly patient are often prescribed for visual correction and/or corneal rehabilitation. The success of contact lenses in the geriatric patient is often limited by such factors as abnormal adnexal physiology, decreased manual dexterity, high degrees of refractive error, and low vision. Assessment of these factors prior to contact lens fitting can greatly increase the success of these unique contact lens applications. Indications and contraindications for contact lenses in the elderly, the need for special lens handling and care by family members, and available specialty lenses will be discussed.

Checklist for the removable prosthesis wax trial insertion appointment

A checklist is described that is designed to permit a systematic evaluation of the factors involved in the trial insertion appointment. The checklist aids both the student and the instructor in assuring that items are not overlooked during this important appointment. More equitable grading of the student's preparation and knowledge is facilitated. The checklist also serves as an excellent patient approval form.

Rotational path partial denture design: a 10-year clinical follow-up--Part I

A conventional removable partial denture that uses a straight path of placement requires that all rests and clasps be seated simultaneously. The incorporation of a dual, curved, or rotational path of placement permits one portion of the framework to be seated first, followed by the remainder of the framework. This procedure usually permits a reduction in the number of clasps in the framework without compromising the biomechanical properties of the prosthesis. Rotational path designs that eliminate clasps reduce tooth coverage by components and often enhance esthetics, thereby contributing to improved patient acceptance.

Rotational path partial denture design: a 10-year clinical follow-up--Part II

A review of the rotational path removable partial denture design concept has been presented. The rigid direct retainers used in these designs satisfy the basic requirements of clasp designs. The reported results of a survey of the members of The Academy of Prosthodontics may provide insight into the reasons for reluctance on the part of some practitioners to use the concept more often when indicated. Possible reasons include the following: lack of sufficient understanding of the concept, difficulty in obtaining knowledgeable laboratory support, absence of documented evidence of long-term clinical success, and a general lack of confidence in the efficacy of the procedure as described in the literature. This article presents references that are available to improve the understanding of technicians and dentists with regard to the rotational path concept. In addition, several patients followed up for 10 or more years demonstrated long-term clinical success.

Esthetic implant restorations

The success achieved with osseointegrated implants in the treatment of edentulous patients created a demand for their use in partially edentulous patients as well. New challenges confronted restorative clinicians with this group of patients, particularly esthetic challenges. New components and techniques had to be developed to improve the esthetic results. The "UCLA" abutment allows the restoration to connect directly to the implant fixture, emerging through the mucosa with a natural appearance. Esthetic titanium abutments can now also be used for a subgingival restorative design that creates a natural and gradual emergence profile similar to the UCLA abutment while maintaining more of the time-tested biomechanical principles of the older cylindrical titanium abutments.

Photogrammetric measurements of implant positions. Description of a technique to determine the fit between implants and superstructures

A photogrammetric technique was designed to measure the position of dental implants in 3 dimensions to enable assessment of the fit of superstructures placed on the implants. A relatively simple camera set-up was developed and tested. Calibration of the camera was performed in a high-precision analytical plotter and revealed a film measurement accuracy of 0.005 mm. The achieved measuring accuracy for clear and well defined points on clinical components was found to be around 0.02 mm. To find the center points of the implants, points on the circumference were measured. These points are not well defined, which resulted in an estimation of the center point of the implant with a precision of 0.05 mm. Independent measurements of a prosthesis with 5 implants were also within the precision of 0.05 mm. The angular orientation of the top surface of the implant cylinder (abutment, brass replica of gold alloy cylinder of the framework) was measured with a precision of 0.01 radians, which corresponded to an error with a peripheral gap of about 0.03 mm. This value was about 5-10 times lower than the clinical fit between frameworks and abutments, measured in 3 randomly selected clinical cases.

The use of hypnosis in the management of 'gagging' and intolerance to dentures

Hypnosis is not a therapy, but can provide the clinician with a set of techniques which may be used to augment or facilitate a particular course of treatment. The importance of the patient's history and clinical findings in the diagnosis of intolerance to dentures and the selection of patients for hypnosis is discussed. Principles of treatment using relaxation, anxiety control, conditioning/desensitisation and confidence boosting techniques are described. Some examples of typical case histories are used to illustrate the application of a variety of techniques that have been found to be successful.

The adhesive-corrected implant framework

To avoid stress between bone, implant and supra construction, the connection between implants must be passive. This is clinically difficult, if not impossible, to achieve with current procedures. Two techniques are presented in which pre-machined titanium abutment cylinders or discs are intra-orally luted to a cast supra structure. The objective is to create a stress-free implant frame-work connection. Possible advantages and disadvantages are discussed.

Laparoscopic prosthesis fixation rectopexy for complete rectal prolapse

Five women aged 64-81 years with complete rectal prolapse and incontinence were treated by laparoscopic mobilization of the rectum and posterior fixation to the presacral fascia using Marlex mesh. Mobilization was carried out with standard straight laparoscopic instruments in the first two patients (operating times 3.5 and 4.5 h) and with coaxial curved instruments and ultrasonic dissection in the succeeding three (operating times 2.5, 2.0 and 2.5 h). Restoration to full continence (grade 1) was observed in two patients and to grade 2 in a further two. No recurrence of the prolapse occurred during follow-up of 4-27 months.

Achieving a passive fit for a screw-retained implant-supported maxillary complete arch ceramometal prosthesis: clinical report

A technique is described for the fabrication of a full arch maxillary passive-fitting, screw-retained, rigid ceramometal prosthesis. The two posterior segments containing Screw-Bloc attachments are cast initially. The waxed anterior segment with its attachments is then aligned to the cast posterior segments and cast. Porcelain is fired to the individual segments in an attempt to reduce deformation, which occurs when large ceramometal restorations are constructed. When the prosthesis is completely fabricated, the segments are assembled on the master cast and the attachments on the posterior segments are tapped to receive the screws, which rigidly attach them to the anterior segment. The Screw-Bloc attachment has an irregular configuration that resists rotation of the individual segments. The segments are united once the passively aligned screws are tightened. A clinical report is presented.

Measurement of changes in complete mandibular denture security using visual analogue scales

The security of mandibular dentures for edentulous patients has been quantified using a visual analogue scale. Relining "loose" dentures was shown to produce an increase in the patients' assessments of denture security for 21 out of 23 patients. The security of a denture after relining was found to correlate with the form of the residual mandibular ridge as measured by the mean anterior ridge height.

Copy denture technique: a critique

Many people requesting new complete dentures will have worn dentures (often the same set) successfully for many years. These people are experienced in wearing dentures of a particular shape and size and are familiar with the polished surface shape, the position of the teeth, the base extension and the vertical dimension of occlusion. By maintaining, or slightly modifying these aspects to overcome faults that have developed, patients should find it easier to accept and learn to use their new dentures.

Computed tomography and complete dentures. Morphometric analysis

Ten edentulous patients who were wearing complete dentures that appeared to be well-fitting clinically but were not satisfactory to the patient, were imaged with the use of direct coronal computed tomography. Sections were selected to pass through the maxillary first molar region to study the relationships between the maxillary denture and the supporting tissues, at rest, in maximal intercuspation, and during simulated function. The radiation dose was minimized by limiting the number of cuts made to seven through the same site in different jaw positions both with and without function. Computed tomography offers useful diagnostic information when evaluating patients who have persistently unresoluable denture problems.

Stump problems in traumatic amputation

Stump problems in amputations resulting from employment related injuries were investigated in 397 cases in the Chugoku and Shikoku districts of Japan between 1987 and 1991. Ninety-seven patients (24%) had stump problems which interfered the prosthetic fitting. Stump problems of the upper extremity were seen in about 9% (17 amputees), two thirds of which were skin troubles. Stump problems of the lower extremity were seen in about 37% (80 amputees). Certain complaints were associated with specific methods of amputation; abnormal keratosis in Syme's amputation, equinus deformity in Chopart's amputation, reduced muscle power in above the knee (A/K) amputation and joint dysfunction in below the knee (B/K) amputation. Adequate prosthetic fitting was achieved by the modification of the socket and alignment in almost all amputees with stump problems. In only two cases, Chopart's amputation required subsequent Syme's amputation due to equinus deformity with abnormal keratosis. In almost every case, stump problems are avoidable by means of surgeons' deliberate evaluation of the affected limb and adequate choice of the amputation level.

Marginal fit of restorations before and after cementation in vivo

Triturated luting cements provide convenient clinical handling. This study clinically evaluated the influence of two trituration capsule cement systems on the marginal fit of inner copings for telescoping crowns. Using a randomized parallel design, one coping was cemented using zinc phosphate cement (Phosphacap) and one using a glass-ionomer cement (Ketac-Cem Maxicap) for each of 12 patients. A blind examination of the marginal fit of the restorations was made before and after cementation using the replica technique and a scanning electron microscope. The mean marginal discrepancies for all cast copings were approximately 30 microns (median 23 microns) before cementation. They increased significantly after cementation to 86 microns (median 63 microns) in the zinc phosphate cement copings but to only to 47 microns (median 44 microns) in the glass-ionomer cement copings.

A comparison of microscrew and suture fixation for porous high-density polyethylene orbital floor implants

Twenty oral and maxillofacial surgeons compared the surgical features of microscrew fixation technique with a suture technique for fixation of porous high-density polyethylene orbital floor implants. One investigator then compared material features of these two fixation techniques using recently procured bovine ribs. The microscrew technique was found to be quicker (P > .01) and easier (P > .001), and it provided a higher quality of fixation (P > .001) than the suture technique. The microscrew/implant system had a greater pullout strength (P > .001) and shear strength (P > .001) than the suture/implant system.

Marginal adaptation

A critical review of studies assessing the marginal adaptation of direct placement, plastic restorations is presented. The effects upon adaptation of cavity design and location of cavity margins are examined, together with the effects of differing placement and finishing techniques. Both the choice of restorative material and the use of liners/bases are shown to influence the quality of restoration margins. Techniques used in both in vivo and in vitro assessment are reviewed, however it appears that a wide variety of methodologies exist and the establishment of standard, published criteria for the qualitative assessment of marginal adaptation is recommended.

Retention designs for bone-anchored facial prostheses

A facial prosthesis can be retained by bone-anchored implants and by a retentive bar. Because tissue response is critical around the abutments, the retentive bar should be constructed so that it is comfortable, conveniently hygienic, and designed without compromising the contours of the prosthesis.