Final Prosthesis Research Articles

Classification system on the selection of number of implants and superstructure design on the basis available vertical restorative space and interforaminal distance for implant supported mandibular overdenture.

Purpose:The rehabilitation of the edentulous mandible is a challenge due to various limiting factors, of which the available vertical restorative space (AVRS) has been well understood in the literature. However, other anatomic variations such as arch form, arch size, and also the interforaminal distance (IFD) (due to the presence of mandibular nerve) are influential in the selection of size and position of implants, and thereby the prosthetic design.Materials and Method:In the present study, 30 edentulous patients from a group of 300 edentulous patients, representing all the three jaw relations (Class I, II, and III) were evaluated for designing a classification that could help in a comprehensive treatment plan for the edentulous mandible. Dental panoramic radiographs of each individual with a trial or final prosthesis were made. The horizontal IFD and AVRS values were calculated.Results:One-way analysis of variance followed by post-hoc test (multiple comparison) and Bonferroni method having P < 0.05 as significant value showed an overall mean of 38.9 mm for horizontal distance and 13.69 mm for the AVRS in 30 edentulous patients.Conclusion:The results showed that in the majority of cases (90%) there is insufficient space to place a bar attachment supported by five implants for mandibular overdentures. This suggests that a universal treatment plan cannot be followed due to varying anatomic factors. Hence, it becomes imperative to have a set of clinical guidelines based on the AVRS and IFD, for the selection of implant number and type of attachment. The article proposes a simple classification system based on the AVRS and IFD for establishing guidelines in the treatment planning of the edentulous mandible, to aid in selection of implant size, number, and position along with the associated prosthetic design.

Consecutive Case Series of Healed Single-Molar Sites Immediately Restored with Wide-Diameter Implants: A 1-Year Evaluation.

Introduction. To evaluate outcomes of wide-diameter (6 mm) implants immediately provisionalized with cement-retained single crowns in posterior molar sites. Materials and Methods. Forty-eight consecutive patients received a total of 53 moderately rough-surface, 6 mm diameter implants in healed sites. All implants were immediately provisionalized with a cement-retained provisional crown. Final prosthesis with cement-retained porcelain fused to metal crowns was delivered 3–6 months later. Patients were followed up for 1 year. Outcome measures were implant failures and success rate, complications, marginal bone levels, bone level changes, papilla index, bleeding on probing, and inflammation. Results. One patient was lost to follow-up. At one year, the implant survival and success rate were 98.1%. The mean marginal bone loss after 1 year was −0.17 ± 1.84 mm. Ideal papilla score was recorded at 83.8% of the sites. More than 95.6% of the sites showed no bleeding or inflammation. No procedure-related or device-related adverse events were reported. Conclusion. Wide-diameter (6 mm) implants can safely and successfully replace single posterior molars. Longer follow-up studies are necessary to evaluate the long-term success of these implants.

Implant – Supported Full Mouth Rehabilitation: A Guided Surgical and Prosthetic Protocol

Implant – Supported Full Mouth Rehabilitation: A Guided Surgical and Prosthetic Protocol

Full Mouth Rehabilitation of an Ectodermal Dysplasia Patient with Hypodontia and Reduced Vertical Dimension Using Metal Ceramic Restorations: A Case Report

Oral rehabilitation of the hypohidrotic ectodermal dysplasia (HED) patient is recommended to improve both the sagittal and vertical skeletal relationship as well as to provide improvements in esthetics, speech, and masticatory efficiency. It has also proven to boost the self-esteem of the patient. This clinical report describes the full mouth reha- bilitation of a HED patient who was clinically monitored for a period of 3 months to evaluate her adaptability to the new increased vertical dimension at occlusion achieved with the help of an overlay removable partial denture (ORPD) for a period of 3 weeks, and provisional restoration for an additional period of 3 months to determine esthetic and functional outcome with provisional restoration, which was followed by the placement of final definitive prosthesis, designed based on shortened dental arch (SDA) scheme, which eliminates the need for invasive implant surgeries. The occlusal cant was corrected by a conservative approach using the macroesthetic elements of smile design, which helps to establish the occlusal plane in a simple and reliable technique.

From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients.

Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT), the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA) temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy) and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results.

Marginal Bone Remodeling around healing Abutment vs Final Abutment Placement at Second Stage Implant Surgery: A 12-month Randomized Clinical Trial.

The periimplant bone level has been used as one of the criteria to assess the success of dental implants. It has been documented that the bone supporting two-piece implants undergoes resorption first following the second-stage surgery and later on further to abutment connection and delivery of the final prosthesis. The aim of this multicentric randomized clinical trial was to evaluate the crestal bone resorption around internal connection dental implants using a new surgical protocol that aims to respect the biological distance, relying on the benefit of a friction fit connection abutment (test group) compared with implants receiving conventional healing abutments at second-stage surgery (control group). A total of partially edentulous patients were consecutively treated at two private clinics, with two adjacent two-stage implants. Three months after the first surgery, one of the implants was randomly allocated to the control group and was uncovered using a healing abutment, while the other implant received a standard final abutment and was seated and tightened to 30 Ncm. At each step of the prosthetic try-in, the abutment in the test group was removed and then retightened to 30 Ncm. Horizontal bone changes were assessed using periapical radiographs immediately after implant placement and at 3 (second-stage surgery), 6, 9 and 12 months follow-up examinations. At 12 months follow-up, no implant failure was reported in both groups. In the control group, the mean periimplant bone resorption was 0.249 ± 0.362 at M3, 0.773 ± 0.413 at M6, 0.904 ± 0.36 at M9 and 1.047 ± 0.395 at M12. The test group revealed a statistically significant lower marginal bone loss of 20.88% at M3 (0.197 ± 0.262), 22.25% at M6 (0.601 ± 0.386), 24.23% at M9 (0.685 ± 0.341) and 19.2% at M9 (0.846 ± 0.454). The results revealed that bone loss increased over time, with the greatest change in bone loss occurring between 3 and 6 months. Alveolar bone loss was significantly greater in the control condition than the test condition. The results of this prospective study demonstrated the benefit of placing a prosthetic component with a stable connection at second-stage surgery, in terms of reduced marginal bone remodeling when compared with conventional procedure. The use of a stable connection in a healing component during try-in stages prior to final restoration placement leads to less periimplant marginal bone loss.

Bloch-Sulzberger症候群（色素失調症）を有する顎形態異常患者を顎矯正手術により治療した1例

Bloch-Sulzberger syndrome (Incontinentia pigmenti) is a genetic disease that displays multiple forms of symptoms including those of the skin, teeth and eyes. Here, we report the case of a patient with Bloch-Sulzberger syndrome on whom we performed orthognathic surgery under general anesthesia. The patient was a 21-year-old female. Oral cavity findings were congenital defects in the right upper jaw 7542, left upper jaw 12578, right lower jaw 754, and left lower jaw 125. Late-stage residual E in the left upper jaw, and abnormal crown morphology of tooth 23 in the right lower jaw and tooth 3 in the left upper jaw were observed. Right cephalometric radiographic analysis revealed marked skeletal mandibular protrusion at SNA: 77.6°, SNB: 89.1°, and ANB: −11.5°. Mandibular protrusion with anomaly in the number of teeth was diagnosed; sagittal split ramus osteotomy and Le Fort 1 osteotomy were performed under general anesthesia. At 18 months postsurgery, the patient is wearing the final prosthesis and occlusion has been confirmed. The present status of occlusion is good and the patient is also satisfied.

Outcome of immediate implant placement with bone augmentation in the anterior maxillary supporting partial denture

Background: Immediate implantation was suggested to reduce the number of surgical interventions and to preserve the alveolar ridge. Implant placement demands a thorough understanding of anatomic, biologic, surgical, and prosthetic principles. Purpose: The aim of the present study was to evaluate the 18 months survival rate of osseointegration, on the basis of clinical and radiographic examinations, for simultaneous bone grafting with immediate implants supporting partial denture with locator attachment in the maxillary esthetic area. Materials and Methods: A total of twenty patients randomly assigned received 45 immediate implants with bone graft supporting maxillary partial overdentures. The clinical analysis of probing depth, bleeding index, plaque index, and radiographic analysis of crestal bone level at a follow-up interval of 6, 12, and 18 months was evaluated. Results: All implants achieved successful osseointegration. The soft tissue architecture remained stable throughout the healing period of the implants as well as after final prostheses delivery, contributing to esthetically pleasing and biologically sound results. Conclusions: Immediate implants with locator attachment supporting maxillary partial denture can be safe, reliable, and a predictable option for the replacement of teeth in the anterior maxillary zone, providing stability to the peri-implant soft tissue.

Comparative Evaluation of Flexural Strength of Provisional Crown and Bridge Materials-An Invitro Study

Provisional restorations serve a key role as a functional and esthetic try-in for the design of the final prosthesis. During selection of materials for this restoration, clinicians must consider physical properties, ease of handling, cost and patient satisfaction and approval. To evaluate and compare the flexural strength of provisional crown and bridge materials available commercially. This in-vitro study was done to compare the flexural strength of six temporary crown and bridge materials available commercially at 24 hours, 8 days and after repair. Three poly methyl methacrylate based materials (DPI, SC10 and Trulon) and three bis-acrylic based composite resins (Protemp, Cooltemp and Luxatemp) were selected. A total of 72 specimens of dimensions 64mm×10mm×2.5mm were prepared from these materials (12 from each material) and divided into two groups (n=36). Specimens were stored in artificial saliva and were fractured after 24 hours and 8 days using Universal Testing Machine. The fractured samples from the 8 days study were then subjected to repair. A uniform space of 2mm and a 450 bevel was maintained for all the repaired samples for better distribution of forces. Flexural strength of these repaired samples was recorded using the same machine. RESULTs were recorded and statistically analysed by one-way Anova and Post hoc tests. RESULTs revealed that there was decrease in flexural strength for all the materials tested from 24 hours to 8 days, though flexural strength between poly methyl methacrylate and bis-acrylic resins was similar at 24 hours and 8 days time interval. A substantial decrease was noticed in the strength of bis-acrylic composite resins after repair. From the current study it can be suggested that though there is decrease in flexural strength for all the materials from 24 hours to 8 days, both can be used to fabricate the provisional restorations. However, in the event of a fracture of a bis-acrylic provisional restoration, it may be more advantageous to make a new provisional restoration than to repair the fractured one.

EFFECT OF IMPLANT ANGULATION AND TRAY TYPE ON DIMENSIONAL ACCURACY OF OPEN TRAY IMPLANT IMPRESSIONS

Statement of the problem: Impression making is a critical clinical step to record accurately the three-dimensional intraoral relationships among implants, teeth and adjacent structures. Inaccuracy during impression making inevitably leads to laboratory errors resulting in lack of precision and misfit of the final prostheses. Several clinical variables may affect the precision of impression particularly in the presence of multiple angulated implants. Purpose: The aim of this study was to evaluate the effect of implant angulation and tray type on dimensional accuracy of open tray implant impressions. Materials and methods: A unilateral free end saddle dentate acrylic maxillary model resembling Kennedy class II starting from a missing canine was used in this study. Three models were duplicated from the acrylic model into epoxy resin master models. In each model, three implants were inserted in the sites of missing canine, second premolar and second molar. According to the direction of implant insertion, the master models were classified into three groups: Group 1: The three implants were inserted with 0° angulation (straight, control group). Group 2: The three implants were inserted with 15° angulation. Group 3: The three implants were inserted with 25° angulation. For all groups, open tray impressions were taken. Impressions of each group were subdivided according to the tray type into two subgroups: Subgroup A: Open tray impressions using custom made trays. Subgroup B: Open tray impressions using ready-made trays. All impressions were poured with type IV dental stone to obtain stone casts. Dimensional accuracy of the impressions was assessed using the travelling microscope. Reference distances were measured by standardized measurement protocol on the stone casts and compared with similar distances in the master models. Results: The results showed that there was a statistically significant difference between the three implant angulations. 25° angulation showed the highest mean of dimensional changes while, there was no statistically significant difference between 0° and 15° angulations in dimension II and III (P value = 0.009 & <0.001 respectively). Regarding the effect of tray type, the results showed that there was statistically significant difference in dimensional changes and the percent of dimensional changes between the two tray types in dimension III (P value = 0.019). Custom made tray showed statistically significant higher dimensional changes compared to ready-made tray. Conclusions: Impressions with ready-made trays showed less dimensional changes in case of 25° angulated implants.

Post-operative hemimaxillectomy rehabilitation using prostheses supported by zygoma implants and remaining natural teeth

OBJECTIVES:This study aimed to evaluate the stability of prostheses supported by zygoma implants and remaining teeth for subjects who had undergone hemi-maxillectomy.METHODS:Ten patients were included in the study. Oral rehabilitation was performed using a temporary prosthesis that was supported by remaining teeth for the first three months. Then, a zygoma implant was placed to provide support for a final prosthesis in addition to the remaining teeth. Each prosthesis was tailor-made according to biomechanical three-dimensional finite element analysis results. The patients were assessed using the prosthesis functioning scale of the Memorial Sloan-Kettering Cancer Center. In addition, retention and bite force were recorded for both the temporary prosthesis and the final prosthesis.RESULTS:The mean bite force of the prosthetic first molar was increased to 69.2 N. The mean retentive force increased to 13.5 N after zygoma implant insertion. The bite force on the prosthetic first molar was improved to 229.3 N.CONCLUSION:Bite force increased significantly with the support of a zygoma implant. The use of zygoma implants in the restoration of maxillary defects improved functional outcome and patient satisfaction.

Beyond osseointegration: Clearing the prosthetic dilemma

It is important for clinicians to understand and adopt a holistic approach to treat their patients. It is a well-known fact that implants have become the forerunners or most preferred option for prosthodontic rehabilitation in patients. However, the patient approaches the clinician not for the implant, but for replacement of the tooth that they lost, i.e., the prosthesis. This article elucidates the various steps undertaken prior to fabrication of the final prosthesis after the surgical phase of implant placement such as impression making techniques, types of abutment options available to clinicians, and abutment selection.

Innovative Replication and Recuperation of Complex Torus Palatinus: A Prosthodontic Case Report

ABSTRACT The prevalence and morphological appearance of torus palatinus has been well documented in the literature. However, adequate literature regarding the precise impression technique and rehabilitation of edentulous maxillary arch with torus is less. Intraoral growths present challenges when trying to capture exact details for impressions starting from the primary to the final stage since the complete seating of conventional impression trays is not possible. In addition, the ability to withstand occlusal loading is compromised as the mucosa tends to be thin. As the extensions of these bony growths can vary, the design of the prosthesis should be optimal to give adequate retention and stability to the prosthesis. Although customized disposable trays are available, they are not cost effective and involve a complex armamentarium. This case report presents a modified impression technique where optimal accuracy was achieved with a design framework having better retention and stability of the final prosthesis. How to cite this article Rajeev V, Arunachalam R. Innovative Replication and Recuperation of Complex Torus Palatinus: A Prosthodontic Case Report. World J Dent 2016;7(4):208-212.

Effects of Abutment Removal and Reconnection on Inflammatory Cytokine Production Around Dental Implants.

The purpose of this study was to examine effects of abutment change on inflammatory cytokine production around implants. Ten partially edentulous patients with a mean age of 60 years were recruited and divided into 2 groups. External Brånemark implants with anodic oxidized surface were installed and submerged in all patients. In the control group, the healing abutments were delivered at the second surgery, and they were removed more than 3 times till the final prosthesis delivery. In the test group, the final abutments were delivered at the second surgery. At different time points during the treatment, periimplant crevicular fluid was collected, and proinflammatory cytokines (interleukin-1β [IL-1β] and tumor necrosis factor [TNF]-α) were measured with enzyme-linked immunosorbent assay. The bone level was measured on the radiograms and clinical indices were also taken. All implants were osseointegrated. In the test group, IL-1β level and probing depths were less in test group patients compared with the control group patients, whereas TNF-α level and bone level were not different between the groups. Although TNF-α and bone levels were not significantly different, delivering final abutment at the second surgery would induce less inflammation in the tissues around the implant.

PROSTHETIC EAR RECONSTRUCTION APPLYING COMPUTER TOMOGRAPHIC (CT) DATA AND ADDITIVE MANUFACTURING TECHNOLOGIES

The treatment of auricle defect can be by surgical or prosthetic ear rehabilitation depending on the condition. Current practice by surgeon for prosthetic ear rehabilitation require patient to go for osseointegrated craniofacial implant surgery for retention of the prosthetic ear. Impression technique play a vital role in accurate reproduction of affected and unaffected ears, orientation of the ear during wax try in and fabrication of ear prostheses. Traditionally, the wax pattern was created from the impression taken from patient and the final prosthesis is processed with silicone material. This conventional method has always been time consuming, massive work and caused discomfort to patient. Moreover the accuracy of the final prosthetic sometimes was not satisfied. Improvement in medical imaging technology whereby data from computerized tomography (CT) in 2D format can be converting to 3 dimensional images gave tremendous view for surgeon to visualize the result. A new and impressive advance in the development of additive manufacturing technology is now being able to be applied in medical field. The widespread use of computer-aided design (CAD) combine with computer aided manufacturing (CAM) produced the momentum and desire to translate the 3-D images into physical models. Studies and research have indicated the viability of using medical imaging technology, computer aided design (CAD) and additive manufacturing techniques in prosthetics. This paper proposed a novel method of fabricating the prosthetic ear applying mirror image technique to reconstruct the missing ear, and then fabricate the 3D model of the prosthetic ear using Stereolitography (SLA) technology that will become the master mold to produce the final prosthetic ear. This method eliminates the traditional wax pattern procedure. A clinical study is done onto a patient in HUSM and comparison is made between traditional method vs new approach using computer aided technology. Result showed that there is significant different between traditional and new approach design. The new method also shows time reduction during design and fabrication stage.

Nuovo approccio per soluzioni conometriche

ObjectivesThe aim of this study is to present a new approach to achieve a final restoration on immediate loaded implants and with custom conical abutments, with no need for implant impression. Materials and methodsWe treated the edentulous maxilla of a patient who had a complete denture. After obtaining a CBCT scan and initial impressions, we processed the case through Simplant (Dentsply IH, Mölndal, Sweden), a software for guided surgery. We obtained the master cast by modifying the initial cast through Simplant surgical guide. Four Atlantis custom abutments (Dentsply IH; conus abutments with 5° angulation) were subsequently ordered and the final prosthesis was fabricated in the lab. During the second appointment in dental office, we inserted four Astra Tech EV implants (Dentsply IH) through flapless guided surgery, screwed the conical abutments and finally inserted the immediate load overdenture. ResultsWe inserted the implants and applied the overdenture in one appointment with no complications. ConclusionsWe significantly decreased the time spent on dental chair and completed the treatment in a minimally invasive and predictable way. The techniques and materials used are supported by strong scientific evidence and are quite versatile.

Distal femoral fracture during primary total knee arthroplasty.

To review 6 cases of periprosthetic distal femoral fracture during total knee arthroplasty (TKA). Of 778 women and 691 men who underwent primary TKAs using posterior-stabilised (n=1240), cruciate-retaining (n=165), or semiconstrained (n=64) implant, 5 women and one man with a mean age of 73.3 years and a mean body mass index of 31.6 kg/m(2) sustained an intra-operative periprosthetic distal femoral fracture and were followed up for a mean of 12.8 (range, 2-39) months. Respectively in patients with a posterior-stabilised, cruciate-retaining, or semi-constrained implant, the intra-operative fracture rates were 0.32%, 0%, and 3.13%. For women, the respective rates were 0.46%, 0%, and 5.10%. Intra-operative fracture was 9.69 times (p=0.03) more likely to occur in patients with a semi-constrained implant than those with a posterior-stabilised implant, and was 4.44 times (p=0.22) more likely to occur in women than in men. Half of the fractures occurred during the trial phase when the tibia was reduced onto the femur, and half during final prosthesis implantation. Distal femoral fracture during primary TKA is rare and associated with the use of a semiconstrained implant. Preserving as much bone in the distal femur is advised.

Systematic approach to preparing ceramic–glass composites with high translucency for dental restorations

ObjectiveCeramic composites are promising materials for dental restorations. However, it is difficult to prepare highly translucent composites due to the light scattering that occurs in multiphase ceramics. The objective of this work was to verify the effectiveness of a systematic approach in designing specific glass compositions with target properties in order to prepare glass infiltrated ceramic composites with high translucency. MethodsFirst it was necessary to calculate from literature data the viscosity of glass at the infiltration temperature using the SciGlass software. Then, a glass composition was designed for targeted viscosity and refractive index. The glass of the system SiO2–B2O3–Al2O3–La2O3–TiO2 prepared by melting the oxide raw materials was spontaneously infiltrated into porous alumina preforms at 1200°C. The optical properties were evaluated using a refractometer and a spectrophotometer. The absorption and scattering coefficients were calculated using the Kubelka–Munk model. ResultsThe light transmittance of prepared composite was significantly higher than a commercial ceramic–glass composite, due to the matching of glass and preform refractive indexes which decreased the scattering, and also to the decrease in absorption coefficient. SignificanceThe proposed systematic approach was efficient for development of glass infiltrated ceramic composites with high translucency, which benefits include the better aesthetic performance of the final prosthesis.

Esthetic restoration of malpositioned anterior teeth by tooth shape and gingival contour modification : a clinical report

In esthetic treatments, it is important to consider the arrangement of teeth and the relation between the teeth and soft tissues. A precise diagnosis and establishing an appropriate treatment plan is essential in an esthetic treatment of anterior maxillary teeth. For a fixed prosthesis to meet esthetic expectations, It is crucial to achieve symmetry and adequate proportions of the gingival contour around the crowns. To achieve an esthetic improvement and creating a favorable environment for gingival healing of a physiologic gingival contour, gingivectomy, crown lengthening and forced eruption can be applied to the appropriate site. All ceramics or porcelain laminate veneer can be selected for esthetic improvement of teeth contour and shade. In this case report, malposition of the remaining teeth made it hard to get an esthetic appearance. Gingivectomy, crown lengthening and provisional restoration insertion were performed before the final prosthesis fabrication to reform the gingival form. This case presents satisfying result esthetically and functionally.

Alignment in knee flexion position during navigation-assisted total knee arthroplasty.

The aim of this study was to demonstrate the lower limb alignment in knee flexion position after navigation-assisted total knee arthroplasty using the gap technique and to identify the correlative factors. One hundred and twenty consecutive osteoarthritic knees (120 patients) were prospectively enrolled for intraoperative data collection. All TKA surgeries were performed using the navigation system (OrthoPilot™, version 4.0; B. Braun Aesculap, Tuttlingen, Germany). Before and after final prosthesis implantation, the lower limb navigation alignment in both knee extension (0°) and knee flexion (90°) position was recorded. The knee flexion alignment was divided into three groups: varus, neutral and valgus alignment. To determine the factors of the alignment in knee flexion position, preoperative demographics, radiologic and intraoperative data were obtained. Pearson's correlation (r) analysis was performed to find the correlation. The Knee Society Score and Western Ontario and McMaster Universities Osteoarthritis Index were compared between groups. Although all postoperative extension alignment was within neutral position (between -2° and +2°), postoperative knee flexion alignment was divided into three groups: varus (≤-3°), 24 cases (20%); neutral (between -2° and +2°), 85 cases (70.8%) and valgus (≥+3°) alignment, 11 cases (9.2%). There were a good correlation of alignment in knee flexion position with the rotation of femoral component relative to posterior condylar axis (r=-0.502, p=0.000) and weak correlations with posterior femoral cut thickness (lateral condyle) (r=0.207, p=0.026), medial flexion (90°) gap after femoral component rotation adjustment (r=0.276, p=0.003). Other variables did not show correlations. There were no statistical clinical differences between varus, neutral and valgus knee flexion alignment groups. About 30% of the cases showed malalignment of more than 3° in knee flexion position although with neutral alignment in extension position. The knee flexion alignment had a good correlation with the rotation of femoral component relative to posterior condylar axis. Neutral alignment in knee flexion position may be adjusted by femoral component rotation especially by the use of navigation system. IV.