Mortality after tricuspid valve procedures: A 27-year, single-center experience.

OBJECTIVE: To assess mortality after tricuspid valve (TV) surgery in a large single-center patient cohort. METHODS: Data from 392 TV procedures performed between 1989 and 2015 in 388 adult patients were retrospectively reviewed. The patients were divided into groups according to the type of concomitant procedure, ie, coronary artery bypass grafting (CABG) (TV + CABG group; n = 87), other valve surgery (TV + valve group; n = 240), or an isolated TV procedure with or without another minor procedure (isolated TV group; n = 65), and the era of the operation, ie, 1989-2005 (n = 173) or 2006-2015 (n = 219). Control groups of patients who underwent other valve procedures and/or CABG during the same time periods were used for comparison. RESULTS: During the most recent era, the annual number of TV procedures increased 2.4-fold, mainly for TV + valve procedures (2.8-fold). Within the TV + valve group, a larger proportion of patients had mild-to-moderate tricuspid regurgitation (grade ≤2) compared with the first-time period (P = .001). The TV + CABG group had significantly greater mortality than both the other groups during both time periods, whereas isolated TV procedure had the lowest mortality rates with the exception of the TV + valve group during the most recent era (P = .41). Survival for patients undergoing TV + valve procedures has improved significantly during the last decade (P = .001) and was comparable with that for other valve operations during this period. CONCLUSIONS: In the last decade, TV repair has been performed more frequently and at lower grades of tricuspid regurgitation compared with previously, and mortality after TV procedures has decreased.

Estimating Long-Term Vagus Nerve Stimulation Effectiveness: Accounting for Antiepileptic Drug Treatment Changes.

OBJECTIVE: To investigate the effectiveness of vagus nerve stimulation (VNS) in combination with pharmacological therapy in a longitudinal retrospective study at a single center. MATERIALS AND METHODS: Data from 130 consecutive patients implanted with a VNS device between the years 2000 and 2013 was analyzed. Seizure frequency and pharmacological antiepileptic drug (AED) treatments were recorded prior to as well as at one, two, and five years after VNS implantation. RESULTS: Median age at epilepsy onset was five years and mean years from diagnosis to VNS implantation was 16.5 years. There was a significant seizure reduction overall (all p < 0.001). The responder (≥50% seizure frequency reduction) rate increased from 22.1 to 43.8% between the first and fifth year for the cohort as a whole, with the largest increase between the first and second year (22.1-38.1%) and regardless of AED changes. VNS effectiveness did not differ between patients who altered or remained on the same AEDs. Patients were treated with a median of three AEDs throughout the study and the number of AEDs significantly increased after two (p = 0.007) and five (p = 0.001) years. CONCLUSIONS: VNS is a well-tolerated palliative neuromodulatory treatment for drug resistant epilepsy with a 43.8% seizure reduction after five years. Our data supports the idea that VNS effectiveness increases with time. Therefore we suggest that VNS should be evaluated for at least two years after implantation. AED changes should try to be kept to a minimum during evaluation in order to determine the effectiveness of VNS.

Quality of Life after Free Fibula Flap Reconstruction of Segmental Mandibular Defects.

BACKGROUND: Free fibula flap (FFF) is considered gold standard in the reconstruction of mandibular defects. Despite the frequent use, patients' quality of life (QoL) after reconstruction has been sparsely investigated. This study aims to evaluate QoL and outcomes in patients who have undergone FFF reconstruction of segmental mandibular defects. METHODS: A retrospective cohort study of consecutive patients (n = 73) operated at a single center during the years 2000 to 2014 was performed. Charts were reviewed and all living patients (n = 41) were invited to fill out three quality of life questionnaires (QLQ): SF-36, EORTC QLQ-C30, and QLQ-H&N35. Factors associated with poor outcome were derived from regression models and the results of the QLQs were compared with Swedish reference populations. Subgroup analysis was performed for two groups depending on reconstructive indication: cancer and osteoradionecrosis (ORN). RESULTS: The response rate of the QLQs was 93%. General QoL did not differ from reference populations, but the study group had significantly larger proportions of poor functioning patients in three domains in EORTC QLQ-C30: global health status, role functioning, and social functioning. Patients also reported a high incidence of poor functioning/high symptom burden in EORTC QLQ-H&N35, with a significantly higher frequency in the ORN group compared with the cancer group for the domains "swallowing" and "social eating." The overall flap success rate was 92% and complication rate was 48%. Previous surgery had a significant association with reoperation due to bleeding, and longer duration of surgery was significantly associated with local infection. CONCLUSION: When evaluated with validated QLQs, most patients experienced persistent functional loss in one or several domains, but still perceived a general QoL that is close to that of reference populations. Patients having ORN as the indication for surgery, as compared with cancer, reported a higher frequency of poor functioning patients in disease-specific QoL domains.

Surgical treatment for isolated mitral valve endocarditis: a 16-year single-centre experience.

OBJECTIVES: Despite progress in management, mitral valve endocarditis (MVE) is still a life-threatening disease. We report our experience in surgical treatment of infective isolated MVE. METHODS: A total of 140 operations in 128 patients for MVE performed between January 2000 and December 2015 were included in a retrospective study. There were 109 (78%) operations for native and 31 (22%) operations for prosthetic valve endocarditis. Preoperative and postoperative characteristics and mortality of patients were registered. Cox regression identified factors associated with mortality. Mean follow-up period was 68 months (range 1-168 months) and 100% complete. RESULTS: There were 13 deaths within 30 days after the 140 operations (9%). Severe perioperative complications occurred in 59 (42%) operations. Overall cumulative survival was 73% ± 4 at 5 years and 62 ± 5% at 10 years after the first operation. Age, diabetes, EuroSCORE II and perivalvular abscess were independent predictors for long-term mortality. Valve repair was performed in 76 (54%) operations and replacement in 64 (46%) operations. Thirty-day mortality for repair was 1%, and 5-year and 10-year cumulative survival was 86 ± 4% and 77 ± 6%, respectively. In the replacement group the 30-day mortality was 19% and cumulative survival at 5 years and 10 years was 55 ± 7% and 41 ± 8%, respectively. Postoperative complications occurred in 21% and 67%, respectively, after operations for repair and replacement. Ten (8%) patients had 12 reoperations for recurrent endocarditis. CONCLUSIONS: MVE requiring surgical treatment is a challenging disease with high hospital mortality after valve replacement. Mitral valve repair can be performed in suitable endocarditis patients with excellent results. Age, diabetes and EuroSCORE were independently associated with mortality in a multivariable model.

Patient determinants as independent risk factors for postoperative complications of breast reconstruction.

BACKGROUND: Breast reconstruction is an essential component in the treatment of breast cancer. Postoperative complications after breast reconstruction are common and affect patient satisfaction. Determining independent risk factors using patient characteristics could be advantageous for patient assessment and counseling. METHODS: We retrospectively enrolled 623 consecutive patients who underwent reconstruction with a deep inferior epigastric perforator flap (DIEP), latissimus dorsi flap (LD), lateral thoracodorsal flap (LTDF), or tissue expander with a secondary implant (EXP) in this study. Information on demographic and perioperative factors was collected, as well as information on all postoperative complications. Logistic regression was used to analyze associations between possible patient-related risk factors and postoperative complications. RESULTS: Smoking was associated with the highest number of early overall complications [odds ratio (OR) 2.05, 95% confidence interval (CI) 1.25-3.37, P=0.0005], followed by body mass index (BMI) (OR 1.07, 95% CI 1.01-1.13, P=0.017). High BMI was associated with the highest number of late overall postoperative complications (OR 1.06, 95% CI 1.00-1.11, P=0.042), followed by history of radiotherapy (OR 1.66, 95% CI 1.01-2.74, P=0.046). When the risk factors were combined, the risk for postoperative complications rose exponentially. CONCLUSIONS: Our results provide evidence that patients should cease smoking and overweight patients should lose weight before undergoing breast reconstruction. Additionally, if the patient has received radiotherapy, the reconstruction method should be carefully chosen. High BMI, history of radiotherapy, and smoking are independent risk factors for many types of both early and late postoperative complications in breast reconstructive surgery. Combining these risk factors multiplies the risk of postoperative complications.

Long-Term Health-Related Quality of Life after Breast Reconstruction: Comparing 4 Different Methods of Reconstruction.

BACKGROUND: Studies have confirmed that breast reconstruction is beneficial to improve health-related quality of life (HR-QoL) in breast cancer patients. Our aim was to compare 4 different methods of breast reconstruction on patient satisfaction and HR-QoL using both general and specific patient-reported outcome instruments. METHODS: Retrospectively, 459 patients who underwent breast reconstruction with a deep inferior epigastric artery perforator (DIEP) flap, latissimus dorsi flap, lateral thoracodorsal flap, or expander with secondary implant and who had responded to the questionnaires were enrolled. Questionnaire answers, together with demographic and follow-up data, were statistically analyzed and compared between groups. Short-Form 36 Health Survey (SF-36) results were also compared with those from a sample of 930 age-matched women from the Swedish population. RESULTS: There were slight differences in the SF-36 results but no significant differences in Psychological General Well-Being Index and EuroQoL-5 Dimension Questionnaire results between groups. Analysis of Breast-Q showed that the DIEP group had significantly higher score on the scale satisfaction with breast, significantly higher score in satisfaction with outcome than the lateral thoracodorsal flap (P = 0.014) and EXP groups (P = 0.024). There were no significant differences in most of the domains of the HR-QoL instruments. The higher satisfaction with breasts and outcome in the DIEP group is interesting, considering the higher complication rates associated with this reconstruction method. CONCLUSIONS: Patients who underwent breast reconstruction with a DIEP flap were more satisfied with their reconstructed breast and outcome than the other 3 groups. Breast reconstruction centers should make DIEP reconstruction widely available to patients after mastectomy.

Blood loss and duration of surgery are independent risk factors for complications after breast reconstruction.

BACKGROUND: Complications after breast reconstructive surgery are common, and they can be caused by a wide range of factors. The aim of the present study was to identify independent perioperative risk factors for postoperative complications after breast reconstruction. METHODS: A retrospective study was performed of 623 consecutive breast cancer patients who had undergone deep inferior epigastric perforator (DIEP) flap, latissimus dorsi (LD) flap, lateral thoracodorsal flap (LTDF), or tissue expander with secondary implant (EXP). Data on demography, perioperative parameters, and complications were collected. Logistic regression models adjusted to the reconstruction method and to confounding demographic factors were used for statistical analysis. RESULTS: Increased blood loss for each 10-ml step increased the risk for overall early complications (p = 0.017), early seroma (p = 0.037), early resurgery (p = 0.010), late local overall complications (p = 0.024), and late fat necrosis (p = 0.031). Longer duration of surgery for each 10-minute step increased the risk of overall early complications (p = 0.019), but, in the univariate model, there was an increased risk for nine different types of complications (p = 0.004-0.029). There was no association between the experience of the surgeon performing the procedure and the frequency of complications. CONCLUSIONS: Duration of surgery and blood loss during surgery are independent risk factors for postoperative complications, and should be minimised. Further research is needed to establish the association between the experience of the surgeon and the occurrence of complications.

Surgical Treatment for Infective Endocarditis: A Single-Centre Experience.

Background A considerable proportion of patients with acute infective endocarditis require surgical treatment. The aim of this study was to collate our short- and medium-term results of surgical treatment of infective endocarditis and to compare the results in native and prosthetic endocarditis. Method Total 254 operations for infective endocarditis from January 2008 to May 2015 were included in this retrospective study. There were 182 operations for native valve endocarditis and 72 for prosthetic valve endocarditis. Patient characteristics, operative details, complications, and mortality were registered. Results The endocarditis was left sided in 247 operations (146 aortic, 78 mitral, and 23 double-valve) and right-sided in 7 (5 tricuspid and 2 pulmonary). Twenty-two patients (8.7%) died within 30 days (7.7% with native valve endocarditis and 11.1% with prosthetic valve endocarditis, p = 0.31). Severe perioperative complications occurred in 99 of 254 operations (39%). Overall cumulative survival at 1 and 5 years was 86% and 75%, respectively, and it was not significantly different for native and prosthetic endocarditis (p = 0.31). Eighteen patients (8%) had one (n = 16) or two (n = 2) recurrent episodes of endocarditis requiring surgery. Conclusion Surgery for infective endocarditis is still associated with a high early mortality rate and a considerable complication rate. Long-term outcome is acceptable. In our study population, morbidity and mortality were not significantly different in native and prosthetic endocarditis.

Re-interventions after endovascular aortic repair for infrarenal abdominal aneurysms: a retrospective cohort study.

BACKGROUND: Early morbidity and mortality are generally lower after endovascular aortic repair (EVAR), than after open repair but re-interventions and late complications are more common. The aim of the present study was to make a detailed description of re-interventions after EVAR-including incidence, indications, procedures, and outcome-with special reference to non-access-related re-interventions. METHODS: This is a retrospective single-center cohort study of re-interventions after standard EVAR with special reference to non-access-related re-interventions. Consecutive patients (n = 405) treated with standard EVAR for non-ruptured (n = 337) or ruptured (n = 68) infrarenal aneurysms between 2005 and 2013 were analysed. Median follow-up was 29 months (range 0-108). RESULTS: Eighty-nine patients (22 %) underwent 113 re-interventions during follow-up. Twenty-seven patients (7 %) had 28 access related re-intervention, 65 patients (16 %) had 85 non-access related reinterventions. Non-access related re-interventions were more common in ruptured aneurysms than in unruptured aneurysms (22 vs. 15 %, p = 0.002). The most frequent indications were endoleak type I (n = 19), type II (n = 21), or type III (n = 5); stent graft migration (n = 9); and thrombosis (n = 14). The most frequent procedures were embolization of endoleak type II (n = 21), additional iliac stent graft (n = 19), proximal extension (n = 12), thrombolysis (n = 8), iliac limb bare-metal stenting (n = 6), and stent graft relining (n = 7). Endovascular technique was used in 83 % of re-interventions. Thirty-day mortality after non-access-related re-interventions was 15 % when initiated from symptoms (rupture or infection) and 0 % when initiated from follow-up findings (p = 0.014). Cumulative survival five years after EVAR was 72 % in patients with a re-intervention and 59 % in patients without (p = 0.21). CONCLUSIONS: Non-access-related re-intervention rates are still considerable after EVAR and more frequent after ruptured aneurysms. Endoleak embolization is the most frequent procedure, followed by additional iliac stent grafts. Outcomes after re-interventions are generally good, except when initiated by rupture or infection.

Reexploration for Bleeding and Its Association With Mortality After Cardiac Surgery.

BACKGROUND: Excessive bleeding after cardiac surgical procedures sometimes necessitates reexploration. This study described the associations between reexploration for bleeding and morbidity and mortality after cardiac surgical procedures. In addition, independent predictors of reexploration were identified. METHODS: This retrospective observational study based on prospectively registered data included 5,392 consecutive cardiac surgical operations performed from 2009 through 2013. Reexplorations for bleeding within 24 hours of surgical procedures and perioperative morbidity and mortality (30-day, 90-day, and from 90 days until the end of follow-up) were registered. Factors independently associated with mortality, morbidity, and reexploration were identified with multivariable logistic or Cox regression models. Mean follow-up time was 2.4 years (range 0 to 5 years). RESULTS: In this study, 320 patients (6.0%) underwent surgical reexploration. These patients had higher unadjusted mortality at 30 days, 90 days, and more than 90 days (all p < 0.0001). The increased risk remained statistically significant after adjustment for other risk factors at 90 days (odds ratio [OR]: 1.82; 95% confidence interval [CI]: 1.13 to 2.93; p = 0.013) and at more than 90 days (hazard ratio: 1.72; 95% CI: 1.14 to 2.61; p = 0.010). Reexploration was, after adjustment, independently associated with prolonged stay in the intensive care unit (>24 hours), perioperative stroke, perioperative renal injury, need for dialysis postoperatively, prolonged mechanical ventilation (>72 hours), and postoperative mechanical circulation support. Independent risk factors for reexploration were low body mass index, high EuroSCORE, low preoperative fibrinogen plasma concentration, long extracorporeal circulation time, combined valve and coronary artery bypass operations, and dual antiplatelet therapy less than 5 days preoperatively. CONCLUSIONS: Excessive bleeding leading to reexploration is associated with a twofold increased early postoperative mortality rate. Reexploration for bleeding is also associated with mortality beyond 90 days after operation.

Tonically active NMDA receptors--a signalling mechanism critical for interneuronal excitability in the CA1 stratum radiatum.

In contrast to tonic extrasynaptic γ-aminobutyric acid (GABA)A receptor-mediated signalling, the physiological significance of tonic extrasynaptic N-methyl-D-aspartate (NMDA) receptor (NMDAR)-mediated signalling remains uncertain. In this study, reversible open-channel blockers of NMDARs, memantine and phencyclidine (PCP) were used as tools to examine tonic NMDAR-mediated signalling in rat hippocampal slices. Memantine in concentrations up to 10 µM had no effect on synaptically evoked NMDAR-mediated responses in pyramidal neurons or GABAergic interneurons. On the other hand, 10 µM memantine reduced tonic NMDAR-mediated currents in GABAergic interneurons by approximately 50%. These tonic NMDAR-mediated currents in interneurons contributed significantly to the excitability of the interneurons as 10 µM memantine reduced the disynaptic inhibitory postsynaptic current in pyramidal cells by about 50%. Moreover, 10 µM memantine, but also PCP in concentrations ≤ 1 µM, increased the magnitude of the population spike, likely because of disinhibition. The relatively higher impact of tonic NMDAR-mediated signalling in interneurons was at least partly explained by the expression of GluN2D-containing NMDARs, which was not observed in mature pyramidal cells. The current results are consistent with the idea that low doses of readily reversible NMDAR open-channel blockers preferentially inhibit tonically active extrasynaptic NMDARs, and they suggest that tonically active NMDARs contribute more prominently to the intrinsic excitation in GABAergic interneurons than in pyramidal cells. It is proposed that this specific difference between interneurons and pyramidal cells can explain the disinhibition caused by the Alzheimer's disease medication memantine.

A retrospective review of the incidence of various complications in different delayed breast reconstruction methods.

BACKGROUND: Breast reconstruction is a common standard procedure in many centres after breast cancer surgery. The aim of the present study was to investigate and compare the incidence of various complications in different reconstruction methods. METHOD: Six hundred and eighty-five patients were retrospectively classified into five groups: (1) Deep inferior epigastric perforator flap (DIEP), (2) latissimus dorsi flap (LD), (3) lateral thoracodorsal flap (LTDF), (4) expander with secondary implant (EXP), and (5) direct implant (DI). Demographic and perioperative data, the incidence of complications, and follow-up data were collected. RESULTS: There was a significant difference between groups regarding overall early complications (p < 0.001). The DIEP group had the highest incidence of overall complications (50.0%) (p < 0.05). DIEP also had the highest incidence of fat necrosis (18.3%), skin necrosis (22.1%), and incidence of reoperation for complications (26.9%) compared to the other reconstruction methods. In the entire group of patients, the overall incidence of late complications (occurring >30 days after surgery) that needed surgical corrections was 54.7%. The incidence of late complications was 46.2% for DIEP, 66.4% for LD, 74.8% for LTDF, 44.9% for EXP, and 62.9% for DI. The DIEP group had higher incidences of late local complications (fat necrosis, skin necrosis, haematoma, seroma, and wound rupture combined), and scars requiring treatment than the other reconstruction methods. CONCLUSION: Meticulous registration of incidence of different complications in five different breast reconstruction methods revealed high complication rates with all methods. The differences in incidence of complications were related to the operation method used. Based on these results, careful individual planning of a breast reconstruction is mandatory.

Surgical Treatment of Aortic Prosthetic Valve Endocarditis: A 20-Year Single-Center Experience.

BACKGROUND: Despite progress in diagnostic methods and treatment, aortic prosthetic valve endocarditis (PVE) remains a life-threatening disease. We report the outcome of all operations for aortic PVE performed at our institution over the past 20 years. METHODS: Eighty-seven operations performed in 84 patients between 1993 and 2013 were included in this retrospective study. An aortic homograft was used in 56 (64%) cases, a mechanical prosthesis was used in 20 (23%) cases, and a bioprosthesis was used in 11 (13%) cases. Early and late complications and mortality were compared between the first and second decades of our experience. Predictors of mortality were identified with Cox regression. Mean follow-up was 5.5 years (range 0-17 years). RESULTS: Nine patients (10%) died within 30 days, and severe perioperative complications occurred in 36 patients (41%). Overall cumulative survival was 80% at 5 years and 65% at 10 years. Four (12.9%) of the patients treated with mechanical or biological prostheses had a recurrent episode of endocarditis, compared with none of the patients treated with homografts (p = 0.006). During the second decade, 30-day mortality was lower (3.6% versus 22%; p = 0.007) and 5-year cumulative survival was higher (88% versus 66%; p = 0.027). Age, preoperative serum creatinine, and severe perioperative complications were independent predictors of mortality during follow-up. CONCLUSIONS: Aortic PVE is associated with a high rate of early complications and substantial early mortality. Patients who survive the immediate postoperative period have satisfactory long-term survival. The risk of recurrent endocarditis is low, especially in patients treated with homografts. The results have improved during the past decade.

Conservative Healing of an 11 × 9-cm Aplasia Cutis Congenita of the Scalp with Bone Defect.

Objectives Aplasia cutis congenita is a rare congenital condition, and it is difficult to find scientific support for optimal treatment strategies. In addition, these may vary due to defect size, tissue layers involved, contemporary malformations, and the physiologic status of the affected child. Clinical Presentation This case report describes complete skin coverage in 20 weeks and uneventful healing of a large 11 × 9-cm defect of the vertex, involving both skin and skull bone, using conservative treatment. To prevent infection and promote healing, the defect was kept moist and covered at all times, and it was treated with surgical debridement when necessary. For infection control, ionized silver-coated dressings were used in addition to prophylactic antibiotics over the first 3.5 weeks. Follow-up was 2 years. Conclusion Surgical treatment is usually preferred for larger aplasia cutis congenita defects, but it is accompanied with potential risks and will exacerbate secondary reconstruction of alopecia or skull bone defects. This case shows that even very complex defects may be treated conservatively.

Importance of Ca(2+) modifications for osseointegration of smooth and moderately rough anodized titanium implants - a removal torque and histological evaluation in rabbit.

BACKGROUND: Incorporation of Ca(2+) into the titania of anodized titanium surfaces has been found to enhance osseointegration. It provides a stable surface when the ions are incorporated into the oxide layer during the anodizing process. The Ca(2+) may suggestively be prominent sites for mineral induction, attract proteins, and catalyze intracellular cascades. PURPOSE: The aim of the present study was to evaluate the osseointegration of smooth (S(a) < 0.5 µm) and moderately rough (S(a) 1.0-2.0 µm) commercially pure titanium implants, with and without Ca(2+) , in order to reflect on the importance of surface chemistry in relation to topography. MATERIALS AND METHODS: Anodized implants with (OxCa) or without Ca(2+) (Ox), blasted implants (Bl), and blasted anodized implants, with (BlOxCa) or without Ca(2+) (BlOx), were inserted in rabbit femur and tibia. The implant surfaces were characterized using interferometry, scanning electron microscopy, and X-ray photoelectron spectroscopy prior to implant installation. Removal torque (RTQ) measurements were executed on all implants after a healing period of 12 weeks. The implants were, thereafter, removed en bloc with surrounding tissues and prepared for histological evaluations. RESULTS: RTQ measurements of tibial implants revealed significantly higher values for BlOxCa implants (90.7 ± 23.3 Ncm) compared to OxCa (64.6 ± 18.2 Ncm) and BlOx implants (69.7 ± 17.5 Ncm) (p = 0.029). Ca(2+) modification of smooth implants placed in the femur did not reveal any differences. CONCLUSION: Ca(2+) modification of smooth implants resulted in similar interfacial shear strength as moderately rough implants and Ca(2+) modification of moderately rough implants demonstrated the significantly strongest interfacial shear strength when placed in rabbit tibia. This possibly demonstrated surface chemistry compensating for lesser roughness.

Effect of nanoporous TiO2 coating and anodized Ca2+ modification of titanium surfaces on early microbial biofilm formation.

BACKGROUND: The soft tissue around dental implants forms a barrier between the oral environment and the peri-implant bone and a crucial factor for long-term success of therapy is development of a good abutment/soft-tissue seal. Sol-gel derived nanoporous TiO2 coatings have been shown to enhance soft-tissue attachment but their effect on adhesion and biofilm formation by oral bacteria is unknown. METHODS: We have investigated how the properties of surfaces that may be used on abutments: turned titanium, sol-gel nanoporous TiO2 coated surfaces and anodized Ca2+ modified surfaces, affect biofilm formation by two early colonizers of the oral cavity: Streptococcus sanguinis and Actinomyces naeslundii. The bacteria were detected using 16S rRNA fluorescence in situ hybridization together with confocal laser scanning microscopy. RESULTS: Interferometry and atomic force microscopy revealed all the surfaces to be smooth (Sa≤0.22 µm). Incubation with a consortium of S. sanguinis and A. naeslundii showed no differences in adhesion between the surfaces over 2 hours. After 14 hours, the level of biofilm growth was low and again, no differences between the surfaces were seen. The presence of saliva increased the biofilm biovolume of S. sanguinis and A. naeslundii ten-fold compared to when saliva was absent and this was due to increased adhesion rather than biofilm growth. CONCLUSIONS: Nano-topographical modification of smooth titanium surfaces had no effect on adhesion or early biofilm formation by S. sanguinis and A. naeslundii as compared to turned surfaces or those treated with anodic oxidation in the presence of Ca2+. The presence of saliva led to a significantly greater biofilm biovolume but no significant differences were seen between the test surfaces. These data thus suggest that modification with sol-gel derived nanoporous TiO2, which has been shown to improve osseointegration and soft-tissue healing in vivo, does not cause greater biofilm formation by the two oral commensal species tested than the other surfaces.

Nanoporous TiO(2) thin film on titanium oral implants for enhanced human soft tissue adhesion: a light and electron microscopy study.

BACKGROUND: Previous experimental studies have demonstrated direct soft tissue attachment for nanoporous titanium dioxide (TiO(2) ) thin film on implants, while implants without TiO(2) thin film have not shown this capability. PURPOSE: The aims were to evaluate and compare TiO(2) surface-modified experimental microimplants with unmodified microimplants with respect to tissue interaction of the human oral mucosa evaluated by light microscopy on ground sections and semithin sections and transmission electron microscopy on ultrathin sections, and to characterize the inflammatory response and the level of the marginal bone resorption. MATERIALS AND METHODS: The study was a single-center, randomized, comparative, clinical investigation with intrasubject comparison of implants with and without TiO(2) thin film in 15 patients. RESULTS: Two comparator microimplants showed mild erythema and expulsion of fluids. The surrounding tissues around all test implants were clinically healthy. The oral mucosa in contact with the abutment part of the microimplant was 72% for the test implants and 48% for the comparator implants, a statistically significant difference (p =.0268). No statistically significant difference was found in other histological variables. The marginal bone loss in 14 weeks was 0.5 mm for the stable test (n = 11) and 1.7 mm for the stable comparator implants (n = 9; p = .0248). CONCLUSIONS: The nanoporous TiO(2) surface modification has potential clinical benefits because of increased adherence of soft tissue and possible reduced bone resorption.