Mimicking lip features in free-flap reconstruction of lip defects

This paper introduces a technique of lip reconstruction using free flaps in which recognisable landmarks are mimicked by strategic placement of flap junctions. The technique was applied in 15 patients undergoing reconstruction of combined cheek and lip defects using single (n= 9) or double (n= 6) free flaps. Attention to flap design and strategic placement of flap junctions successfully created the vermilion-cutaneous junction, oral commissure and labiomental groove. The presence of these distinguishing features improved the appearance of the reconstructed lip.

Salvia miltiorrhiza and ischemic diseases

The demonstration of beneficial effects of salvia miltiorrhiza (DanShen) on ischemic diseases has revolutionized the management of angina pectoris, myocardial infarction (MI) or stroke in Chinese society. Experimental studies have shown that DanShen dilated coronary arteries, increased coronary blood flow, and scavenged free radicals in ischemic diseases, so that it reduced the cellular damage from ischemia and improved heart functions. Clinical trials also indicated that DanShen was an effective medicine for angina pectoris, MI, and stroke. This review will focus on DanShen's effects in angina pectoris, MI and stroke.

Anti-diabetic property of ethanolic extract of Andrographis paniculata in streptozotocin-diabetic rats

AIM

To investigate the anti-diabetic effect of a crude ethanolic extract of Andrographis paniculata in normal and streptozotocin (STZ)-induced diabetic rats.

METHODS & RESULTS

Oral administration of the extract at different doses (0.1, 0.2, and 0.4 g/body weight) significantly reduced the fasting serum glucose level in STZ-diabetic rats compared to the vehicle (distilled water), but not in normal rats. This effect was dose-dependent. A similar result was seen with metformin (0.5 g/body weight). In the glucose tolerance test, an oral administration of the extract at the same doses suppressed the elevated glucose level in normal and diabetic rats, as did metformin. The effects were also dose-respondent. In the long-term experiment, the extract (0.4 g/body weight), metformin (0.5 g/body weight), and vehicle were given twice daily to diabetic rats for 14 d. On d 15, fasting serum glucose levels were found to be significantly lower in the extract- and metformin-treated groups (P < 0.001) than in the vehicle-treated group. The mean food and water intakes over 14 days were significantly lower in the extract-treated group (P < 0.05, P < 0.01, respectively) and also in the metformin-treated group (both P < 0.001) when compared to the vehicle-treated group. No significant change in insulin level was observed among the 3 groups of diabetic rats. The extract, like metformin, maintained the leptin levels after 14-d treatment, whereas this level was significantly decreased (P < 0.05) in the vehicle-treated group. The activity of hepatic glucose-6-phosphatase (G-6-Pase) was significantly reduced by the extract as well as by metformin (both P < 0.05). No significant difference in hepatic glycogen stores was noted among the 3 groups. The extract caused 49.8% reduction of fasting serum triglyceride levels, compared to 27.7% with metformin. However, neither the extract nor metformin significantly affected serum cholesterol level.

CONCLUSION

The ethanolic extract of A paniculata possesses antidiabetic property. Its antidiabetic effect may be attributed at least in part to increased glucose metabolism. Its hypotriglyceridemic effect is also beneficial in the diabetic state.

Proliferative potential in nasopharyngeal carcinoma: correlations with metallothionein expression and tissue zinc levels

Metallothionein (MT) is a cysteine-rich protein with pleiotropic functions and a high binding affinity for heavy metals. The present study was designed to examine the relationship between MT expression and tissue zinc levels in conjunction with cell proliferation in nasopharyngeal cancer (NPC). Proliferative activity in NPC was quantified by Ki67 immunolabelling and MT expression was determined by immunohistochemistry. Total zinc and subcellular zinc fractions were analysed by flame atomic absorption spectrometry. MT immunostaining was observed in the nuclei of NPC cells, with the percentage MT immunopositivity ranging from 3.0 to 59.7%. Thirteen tumours displayed weak MT staining and the remaining 11 showed moderate to strong immunostaining. There was a significant positive correlation between MT and Ki67 positivity (P = 0.0127). Tissue zinc levels were higher in NPC as compared with benign nasopharyngeal tissues (4.800 +/- 0.4610 versus 2.889 +/- 0.4045 microgram/g dry wt tissue, respectively; P = 0.0122). Nuclear zinc levels in NPC were significantly higher than levels in membrane and cytosolic fractions (mean zinc levels 1.4840 +/- 0.1489, 0.6286 +/- 0.0789 and 0.3014 +/- 0.0250 microgram/mg protein, respectively). A linear relationship was also observed between nuclear zinc levels and MT immunostaining (P = 0.0024) as well as with Ki67 immunopositivity (P = 0.0123). Our results show that MT and zinc are correlated with proliferative activity in NPC, providing further insights into the biology of this enigmatic and aggressive tumour.

Cytotoxic prenylated depsidones from Garcinia parvifolia

Leaf extracts of Garcinia parvifolia provided relatively high yields of four novel, cytotoxic prenylated depsidones. The structures were determined mainly by detailed NMR spectral analysis and X-ray crystallography.

Effects of cis-unsaturated fatty acids on doxorubicin sensitivity in P388/DOX resistant and P388 parental cell lines

It has been reported that several cis-unsaturated fatty acids (c-UFAs) could increase doxorubicin (DOX) accumulation in cancer cells and hence elevate its cytotoxicity. However, some researchers showed that c-UFA pretreatment did not affect its cytotoxicity in special cell lines. It is possible that the different results occurred due to different cellular characteristics. We hypothesized that c-UFA treatment might modulate the activities of some antioxidant enzymes to affect the resistance of cells to DOX. In the present study, we examined how c-UFA pretreatment affected DOX cytotoxicity on mouse leukemia cell line, P388, and its resistant subline, P388/DOX, which we found to have significantly higher glutathione peroxidase (GPx) activity as well as P-glycoprotein (p-gp) overexpression. We chose two c-UFAs, gamma-linolenic acid (GLA) (18:3n-6) and docosahexaenoic acid (DHA) (22:6n-3). Cytotoxicity was measured by MTT (3-(4.5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and trypan blue exclusion assays. DOX accumulation and p-gp expression were measured by flow cytometry. The activities of catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), and GPx were determined for both cell lines with and without treatment with GLA or DHA. Significant DOX accumulation occurred in both cell lines with GLA or DHA pretreatment, but without any change in p-gp expression in either cell line. Sensitivity to DOX cytotoxicity was improved by GLA or DHA pretreatment in P388/DOX in which only SOD activity was significantly increased, but not in the parental cell line P388 in which both SOD and CAT were significantly increased by the pretreatment. However, combined pretreatment of GLA or DHA with antioxidants, pyrrolidinedithiocarbamate (PDTC) or Vitamin C, could sensitize not only P388/DOX but also P388 cells to DOX. We conclude that the effects of c-UFA pretreatment on the sensitivity of cancer cells to DOX not only depend on the change in drug accumulation but also the change in the levels of antioxidant enzyme activities, and suggest that combined administration of c-UFAs, antioxidants, and DOX may be more effective in treating leukemia.

Effects of Averrhoa bilimbi leaf extract on blood glucose and lipids in streptozotocin-diabetic rats

The present study was designed to investigate the hypoglycemic and hypolipidemic activities of an ethanolic extract of Averrhoa bilimbi Linn. leaves (Oxalidaceae, Common name: Bilimbi) in streptozotocin (STZ)-diabetic rats. The optimal hypoglycemic dose (125 mg kg(-1)) was determined by performing the oral glucose tolerance test (OGTT) in both normal and STZ-diabetic rats. To investigate the effect of repeated administration of an ethanolic extract of Averrhoa bilimbi (ABe) leaves, diabetic rats were treated with vehicle (distilled water), ABe (125 mg kg(-1)) or metformin (500 mg kg(-1)) twice a day for 2 weeks. Like metformin, ABe significantly lowered blood glucose by 50% and blood triglyceride by 130% when compared with the vehicle. ABe also significantly increased the HDL-cholesterol concentrations by 60% compared with the vehicle. ABe thus significantly increased the anti-atherogenic index and HDL-cholesterol/total cholesterol ratio. However, like metformin, ABe did not affect total cholesterol and LDL-cholesterol concentrations, but significantly reduced the kidney lipid peroxidation level. These data show that ABe has hypoglycemic, hypotriglyceridemic, anti-lipid peroxidative and anti-atherogenic properties in STZ-diabetic rats.

Navigating the internet maze

The 'internet-driven information age' is a term in common usage, implying that everyone can access all the information they need, when they need it. The purpose of this brief paper is to outline some web sources that highlight the possibilities and potential for accessing web-based knowledge. From this the clinician will be encouraged to follow leads along the labyrinth of links to a greater appreciation of how this resource can be used to shape their practice. Examples of web links are provided for: search engines; library-based sources, including medical databases and electronic journals; evidence-based practice databases, mail-groups; electronic conferences; research centres; and general health sources. Importantly, this review does not aspire to be all-inclusive, for the web changes, chameleon-like, to the seasons. The web is here to stay. It will provide the framework for much education and will guide clients to a greater appreciation of their disease or disability than ever before. It may ultimately be the tool through which health fund agents will promote best practice, including self-help to clients, and therefore direct discriminating individuals to select health practitioners who have been endorsed by professional and fund agencies as providing a contemporary service which conforms to evidence-based practice.

Lipid peroxidation in small and large phospholipid unilamellar vesicles induced by water-soluble free radical sources

The susceptibility of small and large egg yolk phosphatidylcholine unilamellar vesicles to Fe(2+)/histidine-Fe(3+)- and Fenton reagent (Fe(2+)-H(2)O(2))-induced lipid peroxidation was evaluated by measuring the formation of thiobarbituric acid reactive substances (TBARS). It has been found that surface curvature or phospholipid packing exerts significant effect on the oxidative susceptibility of the unsaturated lipid bilayers and the highly curved and loosely packed small unilamellar vesicles (SUVs) exhibit much less resistance to the oxidative stress induced by the water-soluble free radical sources. The presence of lipid hydroperoxides in sonicated vesicles was excluded as the cause for higher level of lipid peroxidation in the phospholipid SUVs. Instead, the experimental results can be explained by the difference in ability of the water-soluble oxidants to penetrate the two types of lipid membranes. This hypothesis is supported by data obtained from fluorescence lifetime and quenching studies.

The lateral forearm flap as a modification of the lateral arm flap: vascular anatomy and clinical implications

The forearm extension of the lateral arm flap was introduced on the basis of the vascular territory of the posterior radial collateral artery extending beyond the elbow into the forearm. However, there is controversy as to whether the posterior radial collateral artery extends as a single trunk below the elbow or if it terminates more proximally with only a rich vascular plexus extending beyond the elbow. The purpose of this study was to revisit the artery's anatomy in the region of the elbow and to study its distribution in the forearm. Using latex and barium-gelatin injections of the posterior radial collateral artery in ten cadaveric upper limbs, it was observed that terminal branching of the artery occurred 4.5 cm proximal to the lateral epicondyle of the humerus. Distal to the epicondyle, the terminal branches of the posterior radial collateral artery were seen to fan out as finely arborized branches supplying the lateral forearm skin. No single, constant vascular trunk to the forearm skin could be identified. Furthermore, in its distribution toward the periphery, the terminal branches of the posterior radial collateral artery took an increasingly superficial course. Proximal to the epicondyle, the vessels lay deep within the subcutaneous fat, whereas distal to the epicondyle, they were very close to skin. These findings suggest that lateral forearm skin cannot be islanded without risk of vascular disruption and that the distally sited flap should include skin proximal to the epicondyle for safety.

Antihyperglycaemic and anti-oxidant properties of Andrographis paniculata in normal and diabetic rats

1. Oxidative stress is believed to be a pathogenetic factor in the development of diabetic complications. In the present study, we investigated the ethanolic extract of the aerial parts of Andrographis paniculata for antihyperglycaemic and anti-oxidant effects in normal and streptozotocin-induced type I diabetic rats. 2. Normal and diabetic rats were randomly divided into groups and treated orally by gavage with vehicle (distilled water), metformin (500 mg/kg bodyweight) or the extract (400 mg/kg bodyweight), twice a day for 14 days. 3. At the end of the 14 day period, the extract, like metformin, significantly increased bodyweight (P < 0.01) and reduced fasting serum glucose in diabetic rats (P < 0.001) when compared with vehicle, but had no effect on bodyweight and serum glucose in normal rats. Levels of liver and kidney thiobarbituric acid-reactive substances (TBARS) were significantly increased (P < 0.0001, P < 0.01, respectively), while liver glutathione (GSH) concentrations were significantly decreased (P < 0.005) in vehicle-treated diabetic rats. Liver and kidney TBARS levels were significantly lower (P < 0.0001, P < 0.005, respectively), whereas liver GSH concentrations were significantly higher (P < 0.05) in extract- and metformin-treated diabetic rats compared with vehicle-treated diabetic rats. Andrographis paniculata significantly decreased kidney TBARS level (P < 0.005) in normal rats. Hepatic superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were significantly lower in vehicle-treated diabetic rats compared with vehicle-treated normal rats. The extract, as well as metformin, significantly increased the activity of SOD and CAT, but had no significant effect on GSH-Px activity in diabetic rats. The extract and metformin did not produce significant changes in the activity of these anti-oxidant enzymes in normal rats. 4. Our results show that oxidative stress is evident in streptozotocin-diabetic rats and indicate that the ethanolic extract of A. paniculata not only possesses an antihyperglycaemic property, but may also reduce oxidative stress in diabetic rats.

Extended lower trapezius island myocutaneous flap: a fasciomyocutaneous flap based on the dorsal scapular artery

The lower trapezius island myocutaneous flap is a useful flap in head and neck reconstruction. It is thin and pliable and can reach defects in most areas of the head and neck. Its usefulness in head and neck reconstruction has often been limited or discouraged by reports of significant failure rates. In this study, the vascular anatomy and clinical use of the extended lower trapezius myocutaneous flap based solely on the dorsal scapular artery system are elucidated, and experience gained performing 20 flaps over the past 5 years by using the extended lower trapezius myocutaneous flap is reported. The vascular anatomy of the dorsal scapular artery system is reviewed in 13 fresh cadaveric dissections by using methylene blue, latex injection studies, and radiologic examination.

Cytotoxic and immunopotentiating effects of ethanolic extract of Nigella sativa L. seeds

In-vitro cytotoxic screening of extracts of Nigella sativa L. seeds (Ranunculaceae) indicated cytotoxicity in the ethyl-acetate fraction (EAF) against different classes of cancer cell lines, P388, Molt4, Wehi 164, LL/2, Hep G2, SW620 and J82, as measured by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The ethyl-acetate column chromatographic fraction (CC-5) showed selectivity against Hep G2, Molt4, and LL/2. CC-5 was relatively non-toxic against human umbilical cord endothelial cells at 50 microg/ml. CC-5 had no stimulatory effect on mouse splenocytes as such. CC-5 and water fraction, however, enhanced the proliferative response in the presence of ConA (3 microg/ml), but not LPS (1 and 6 microg/ml). These data indicate that CC-5 possesses a potent cytotoxic effect as well as a potentiating effect on the cellular immune response. The mechanism whereby it produces this needs to be resolved.

Flavonol-cinnamate cycloadducts and diamide derivatives from Aglaia laxiflora

Leaf extracts of the Malaysian plant Aglaia laxiflora provided two cytotoxic compounds, a new rocaglaol rhamnoside (1), a known rocaglaol (2), new (but inactive) flavonol-cinnamaminopyrrolidine adducts (3-6), and their probable biosynthetic precursors (7 and trimethoxyflavonol). All structures were elucidated primarily by 2D NMR spectroscopy. The structure and stereochemistry of aglaxiflorin A (3) were confirmed by single-crystal X-ray crystallography.

The mechanism underlying the hypocholesterolaemic activity of aqueous celery extract, its butanol and aqueous fractions in genetically hypercholesterolaemic RICO rats

Drinking aqueous celery extract for 8 weeks caused a significant reduction in serum total cholesterol (TC) level in growing genetically hypercholesterolaemic (RICO) rats. In addition, administration of butanol fraction (Fbu) and aqueous fraction (Faq) of celery extract for 7 days by intraperitoneal (i.p.) infusion effectively decreased the serum TC and high-density lipoprotein cholesterol (HDL-C) levels of adult RICO rats. The 8-week study showed that oral intake of celery extract could enhance the 14C-cholesterol/metabolites excretion. The liver and small intestinal sterol synthesis were not affected. Also, long term drinking of aqueous celery extract did not lead to any undesirable side effects on liver functions. The Fbu and Faq lowered serum TC level mainly through increased bile acid excretion but not by modulating the activity of the rate-limiting enzyme for cholesterol biosynthesis, HMG-CoA reductase. Hence, the mechanism elucidated supports that suggested by the 8-week study. A preliminary chemical characterisation of Fbu and Faq fractions by thin layer chromatography (TLC) showed the presence of sugars and amino acids. There is a possibility that polar compounds with sugar or amino acid side chains(s) could contribute to the hypocholesterolaemic action of celery extract.

Anatomic basis of safe percutaneous subclavian venous catheterization

BACKGROUND

The technique of percutaneous catheterization of the subclavian vein by the infraclavicular approach is dependent on the location of the subclavian vein in relation to the clavicle. The purpose of this study was to analyze the anatomic relationship between these two structures and how it is influenced by changes in shoulder positioning.

METHODS

Dissections of the infraclavicular region were performed in seven fresh cadavers and linear measurements made to determine the extent of overlap between the vein and the clavicle in different shoulder positions.

RESULTS

When the shoulder was in neutral position, the subclavian vein was overlapped by the medial third or more of the clavicle and this segment of bone was able to serve as a landmark for the vein. However, shoulder elevation displaced the clavicle cephalad and reduced the degree of overlap. Mild shoulder retraction increased the area of contact between the vein and the undersurface of the clavicle, whereas protraction lifted the clavicle off the vein.

CONCLUSION

Infraclavicular subclavian venipuncture should be performed with shoulders in a neutral position and also in slight retraction. An appreciation of the anatomic relationship between the clavicle and the subclavian vein is the key to successful execution of this technique.

Effects of an ethanolic extract of Gynura procumbens on serum glucose, cholesterol and triglyceride levels in normal and streptozotocin-induced diabetic rats

AIM OF STUDY

The aim was to demonstrate the effects of the leaves of Gynura procumbens (Lour.) Merr. on blood sugar and lipid levels in experimental animals.

METHODOLOGY

We obtained an ethanolic extract of the leaves of G. procumbens and monitored the effects of an oral administration of (i) different single doses of the extract on oral glucose tolerance in streptozotocin-induced diabetic and normal rats and (ii) fourteen doses over 7 days on serum cholesterol and triglyceride levels in streptozotocin-induced diabetic rats. Metformin and glibenclamide were used as positive control drugs.

RESULTS

The extract, at single doses of 50, 150 and 300 mg/kg orally, significantly suppressed the elevated serum glucose levels in diabetic rats; 150 mg/kg was found to be the optimum hypoglycaemic dose. The extract however did not significantly suppress the elevated serum glucose levels in normal rats, unlike glibenclamide. Metformin, but not glibenclamide, improved glucose tolerance in the diabetic rats. When the optimum dose was given to diabetic rats for 7 days, the extract significantly reduced serum cholesterol and triglyceride levels in these rats.

CONCLUSION

These results indicate that the leaves of G. procumbens may have biguanide-like activity.

Lipid peroxidative stress and antioxidative enzymes in brains of milk-supplemented rats

Skim milk cultured with lactic acid bacteria has been previously reported to reduce lipid peroxidation in rat livers. In this study, the effects of skim milk and cultured milk supplementation on peroxidative stress in brains of weanling rats were investigated. We observed a reduction of brain thiobarbituric acid reacting substances (TBARS) concentration in milk-supplemented animals as compared with controls. In brains of control rats, the superoxide dismutase (SOD) enzyme levels were significantly higher than those from the milk-supplemented animals. In addition, SOD activity in control animal brains had a positive correlation with the TBARS concentration. There was no significant differences in the brain glutathione-S-transferase (GST) levels of all the three groups of animals. The results suggest that milk supplementation may be beneficial in reducing peroxidative stress in the developing rat brain.

Prefabrication of jejunum for challenging reconstruction of cervical esophagus

A significant benefit exists for a jejunal replacement of the cervical esophagus, if indicated. The absence of available recipient vessels may impede free tissue transfer. If vascular induction between a vascular carrier and the selected jejunal segment is done as a kind of flap prefabrication, the jejunal interposition flap can be used without the need for complex microsurgery.

Strategies in multiple toe transplantation for bilateral type II metacarpal hand reconstruction

Multiple toe transplantation has been established as an effective means of restoring prehensile function in the metacarpal hand. The attainable outcome, however, must be weighed against potential donor site morbidity. Restoration of prehensile function in bilateral type II metacarpal hands can be achieved by reconstructing three opposable digits in the dominant hand and two opposable digits in the nondominant hand. This article outlines the strategy for optimizing functional outcome and discusses the rationale behind toe selection to reduce donor morbidity.

Combined third and fourth toe transplantation

Multiple toe transplantation has been established as an effective technique for restoring prehensile ability in the metacarpal hand. The combined third and fourth toe transplant is a new toe transplant that has been developed for bilateral metacarpal hand reconstruction. Since 1991, the combined third and fourth toe transplant was added to the armamentarium of toe transplants for metacarpal hands, although its role in metacarpal hand reconstruction has not been described previously. This article introduces the indications for combined third and fourth toe transplant, outlines relevant vascular anatomy, and discusses technical considerations pertaining to toe harvest and transplantation.

The onset of atherosclerotic lesion formation in hypercholesterolemic rabbits is delayed by iron depletion

The theory that iron may play a significant role in atherogenesis by promoting the formation of free radicals is controversial. Previous results using the new technique of nuclear microscopy showed a seven-fold increase in iron concentrations within newly formed atherosclerotic lesions in hypercholesterolemic rabbits compared to healthy artery tissue. In a follow-up time sequence study described here, we show that iron accumulation occurs at the onset of lesion formation. In addition, weekly bleeding decreases the iron uptake into the artery wall and delays the onset of atherogenesis. These results provide direct evidence for a key role of iron in initiating atherogenesis.

A review of mandibular fractures in a craniomaxillofacial trauma centre

This report is a retrospective review of 74 cases of mandibular fractures managed in a craniomaxillofacial trauma centre between January 1994 and May 1998. Demographic data revealed that 85% of the patient population were male, with a mean age of 27.5 years. The commonest causes of injury were motor vehicle accidents (48.6%), followed by assault (16.2%) and accidental falls (17.6%). In 25 patients (33.8%) the fractures were single. Of these, fractures of the condylar region were the most common (8 patients). The remaining patients sustained fractures in two or more anatomic sites. There were other associated facial fractures in 45.9% of patients. Trauma to other systems was present in 37.8%, with orthopaedic and neurosurgical injuries being the most common. Surgical management in the form of open reduction and internal fixation was carried out in 61 patients (82.4%). Maxillo-mandibular fixation was used as an adjunct to maintain occlusion and bony reduction in unstable and comminuted fractures (15 patients, 20.3%), and as the primary mode of treatment in patients with stable, undisplaced fractures, particularly condylar fractures, in which the pretraumatic occlusal relationship was not disrupted (9 patients, 12.2%). A successful outcome was defined as a stable and healed fracture, with restoration of functional occlusion, facial symmetry and facial aesthetics. Complications observed included temporomandibular joint dysfunction (10.8%), malocclusion (9.5%), infection (8.1%), implant exposure (5.4%), and non-union or delayed union (4.1%).

Selective laser sintering: application of a rapid prototyping method in craniomaxillofacial reconstructive surgery

Advances in technology have benefited the medical world in many ways and a new generation of computed tomography (CT) scanners and three-dimensional (3-D) model making rapid prototyping systems (RPS) have taken craniofacial surgical planning and management to new heights. With the development of new rapid prototyping systems and the improvements in CT scan technology, such as the helical scanner, biomedical modelling has improved considerably and accurate 3-D models can now be fabricated to allow surgeons to visualise and physically handle a 3-D model on which simulation surgery can be performed. The principle behind this technology is to first acquire digital data (CT scan data) which is then imported to the RPS to fabricate fine layers or cuts of the model which are gradually built up to form the 3-D models. Either liquid resin or nylon powder or special paper may be used to make these models using the various RPS available today. Selective laser sintering (SLS), which employs a CO2 laser beam to solidify special nylon powder and build up the model in layers is described in this case report, where a 23-year old Chinese female with panfacial fracture and a skull defect benefited from SLS biomodelling in the preoperative workup.