| 1. |
- Chrcanovic, Bruno, et al.
(författare)
-
Survival and complications of implants to support craniofacial prosthesis : A systematic review
- 2016
-
Ingår i: Journal of Cranio-Maxillofacial Surgery. - : Elsevier BV. - 1010-5182 .- 1878-4119. ; 44:10, s. 1536-1552
-
Forskningsöversikt (refereegranskat)abstract
- OBJECTIVE: To assess the survival rate of craniofacial implants (CIs) to support facial prosthesis/epithesis and the prevalence of surgical/biological complications based on previously published studies.METHODS: An electronic search was undertaken in March/2016. Only studies with a minimum of 5 patients were included. Untransformed proportions of implant failures for different regions were calculated. A meta-analysis evaluated the influence of radiotherapy on the failure rates. A meta-regression was performed considering the follow-up period as covariate.RESULTS: Seventy publications included 2355 patients and 8184 CIs (545 failures). The probability of a failure was 5.5% for all CIs (95%CI 4.5-6.5, P < 0.001), 1.2% for CIs in the auricular region (95%CI 0.8-1.5, P < 0.001), 12.2% for the nasal region (95%CI 9.0-15.5, P = 0.017), and 12.1% for the orbital region (95%CI 9.3-15.0, P < 0.001). Radiotherapy statistically affected the CIs rates (OR 5.80, 95%CI 3.77-8.92, P < 0.00001). There was no statistically significant influence of the follow-up time on the proportion of implant failures (P = 0.814). Soft tissue adverse reactions were the most common complications.CONCLUSIONS: Implants placed in the auricular region have a lower probability of failure than those in the nasal and orbital regions. Soft tissue adverse reactions were the most common complications. Radiotherapy significantly affected the CIs failure rates.
|
|
| 2. |
- Hammarfjord, Oscar, et al.
(författare)
-
Surgical treatment of recurring ameloblastoma, are there options?
- 2013
-
Ingår i: British Journal of Oral & Maxillofacial Surgery. - : Elsevier BV. - 0266-4356 .- 1532-1940. ; 51:8, s. 762-766
-
Tidskriftsartikel (refereegranskat)abstract
- Our aim was to evaluate the treatment given to patients with intraosseus ameloblastomas with special emphasis on recurrence and the outcomes of primary and secondary resection. Forty-eight patients who were treated for intraosseous ameloblastoma at 8 centres across Sweden met the inclusion criteria. They showed typical distribution of age, sex, site of lesion, and characteristic presenting features. Eleven of the 48 were initially treated with radical resection and none recurred. Twenty-two of the remaining 37 who were initially treated by conservative resection presented with recurrences. Sixteen of the 22 then had conservative secondary resections, which resulted in further recurrence in 6 patients. Initial radical resection is therefore superior to conservative management as far as recurrences are concerned. We argue, however, that a conservative surgical approach is adequate for many intraosseous ameloblastomas with limited extension, because relapse can be followed by radical resection if clinically indicated in selected cases.
|
|
| 3. |
- Nilsson, Johanna, et al.
(författare)
-
Comparison analysis of orbital shape and volume in unilateral fractured orbits
- 2018
-
Ingår i: Journal of Cranio-Maxillofacial Surgery. - : Elsevier BV. - 1010-5182 .- 1878-4119. ; 46:3, s. 381-387
-
Tidskriftsartikel (refereegranskat)abstract
- Facial fractures often result in changes of the orbital volume. These changes can be measured in three-dimensional (3D) computed tomography (CT) scans for preoperative planning and postoperative evaluation. The aim of this study was to analyze the orbital volume and shape before and after surgical treatment of unilateral orbital fractures using semi-automatic image segmentation and registration techniques. The orbital volume in 21 patients was assessed by a semi-automatic model-based segmentation method. The fractured orbit was compared relative to the contralateral orbit. The same procedure was performed for the postoperative evaluation. Two observers performed the segmentation procedure, and the inter- and intraobserver variability was evaluated. The interobserver variability (mean volume difference ± 1.96 SD) was −0.6 ± 1.0 ml in the first trial and 0.7 ± 0.8 ml in the second trial. The intra-observer variability was −0.2 ± 0.7 ml for the first observer and 1.1 ± 0.9 ml for the second observer. The average volume overlap (Dice similarity coefficient) between the fractured and contralateral side increased after surgery, while the mean and maximum surface distance decreased, indicating that the surgery contributed to a re-establishment of size and shape. In conclusion, our study shows that the semi-automatic segmentation method has precision for detecting volume differences down to 1.0 ml. The combination of semi-automatic segmentation and 3D shape analysis provides a powerful tool for planning and evaluating treatment of orbital fractures.
|
|
| 4. |
|
|
| 5. |
- Nilsson, Johanna, et al.
(författare)
-
Evaluation of in-house, haptic assisted surgical planning for virtual reduction of complex mandibular fractures
- 2021
-
Ingår i: International Journal of Computer Assisted Radiology and Surgery. - : Springer. - 1861-6410 .- 1861-6429. ; 16:6, s. 1059-1068
-
Tidskriftsartikel (refereegranskat)abstract
- The management of complex mandible fractures, i.e severely comminuted or fractures of edentulous/atrophic mandibles, can be challenging. This is due to the three-dimensional loss of bone, which limits the possibility for accurate anatomic reduction. Virtual surgery planning (VSP) can provide improved accuracy and shorter operating times, but is often not employed for trauma cases because of time constraints and complex user interfaces limited to two-dimensional interaction with three-dimensional data. In this study, we evaluate the accuracy, precision, and time efficiency of the Haptic Assisted Surgery Planning system (HASP), an in-house VSP system that supports stereo graphics, six degrees-of-freedom input and haptics, to improve the surgical planning. Three operators performed planning in HASP on Computed Tomography (CT) and Come Beam Computed Tomography (CBCT) images of a plastic skull model and on twelve retrospective cases with complex mandible fractures. The result shows an accuracy and reproducibility of less than 2mm when using HASP, with an average planning time of 15 minutes, including time for segmentation in the software BoneSplit. This study presents an in-house haptic assisted planning tool for cranio-maxillofacial surgery with high usability that can be used for preoperative planning and evaluation of complex mandible fractures.
|
|
| 6. |
- Nilsson, Johanna
(författare)
-
On Virtual Surgical Planning in Cranio-Maxillofacial Surgery
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The complex three-dimensional (3D) anatomy of the cranio-maxillofacial (CMF) region makes surgery a challenging task. Virtual surgical planning (VSP) has the potential to increase accuracy, reproducibility and shorten operation time. Key challenges in VSP are to accurately separate, or segment, certain structures of interest, such as the orbit, from the rest of the image, as well as to create an accurate 3D model of the facial bones and dentition for orthognathic surgery planning. The time required for planning and fabrication of guides for trauma surgery is another challenge. The overall aim of this thesis was to develop and evaluate new virtual planning tools for CMF-surgery and to investigate their usefulness. Study I, II discuss and evaluate image fusion of CT/CBCT and intraoral scanning for orthognathic surgery. A method for virtual bite registration in centric relation (CR) was also proposed. The workflow has the potential to eliminate traditional laboratory work, and may facilitate 3D computer-assisted-planning in orthognathic surgery. Study III deals with orbit segmentation and presents a semi-automatic method, using a deformable model tracing the inside of the orbit via haptic 3D interaction. The method was validated in retrospective unilateral orbital fracture cases. The fractured orbits were compared to the intact side by volume and shape analyses. The method showed high accuracy, precision, time-efficiency and thereby potential to be a powerful tool for planning and evaluating reconstruction of orbital fractures. Study IV evaluates an in-house haptic-assisted VSP system for complex mandibular fractures on a series of retrospective cases and an artificial case. The system showed high precision and time-efficiency, but relatively low accuracy. This study proposes a novel, fast and user-friendly way of integrating VSP into planning mandible trauma surgery and could help in reducing operating time and increase accuracy. Study V is a systematic review and meta-analysis studying potential time benefits using VSP in CMF surgery. The study suggests that VSP shortens the operating time and ischemia time for reconstructive surgery. VSP also appears to shorten the preoperative planning time for orthognathic surgery.
|
|
| 7. |
- Nilsson, Johanna, et al.
(författare)
-
Time matters - Differences between computer-assisted surgery and conventional planning in cranio-maxillofacial surgery : A systematic review and meta-analysis
- 2020
-
Ingår i: Journal of Cranio-Maxillofacial Surgery. - : Elsevier BV. - 1010-5182 .- 1878-4119. ; 48:2, s. 132-140
-
Forskningsöversikt (refereegranskat)abstract
- The aim of the study was to assess if there is a time difference (operative time, ischemia time, planning time and hospitalization) between computer-assisted surgery (CAS) and conventional planning in cranio-maxillofacial surgery. An electronic search was performed in June 2018. Studies comparing time difference between CAS and traditional planning were included. 28 publications were included, with 536 patients in the CAS group and 784 in the control group. 18 studies reported on mandibular/maxillary reconstruction and a meta-analysis was conducted on 15 of these studies. This meta-analysis was undertaken to demonstrate the difference between the groups regarding operative time, ischemia time and hospitalization for mandibular/maxillary reconstruction and showed a decreased operative time for the CAS group with a mean difference of -84.61 min, 95% confidence interval [-106.77, -62,45], p <0.001. Ischemia time was also decreased, with a mean difference of -36.14 min, 95% confidence interval [-50.57, -21.71], p < 0.001. This systematic review and meta-analysis suggests that CAS is shortening the operative time and ischemia time for mandibular/maxillary reconstruction. It also leads to a reduction in hospitalization. Additionally, CAS seems to shorten the preoperative planning time for orthognathic surgery.
|
|
| 8. |
- Nilsson, Johanna, 1986-, et al.
(författare)
-
Time matters - differences between virtual surgical planning and conventional planning in cranio-maxillofacial surgery: a systematic review and meta-analysis
-
Ingår i: International Journal of Oral and Maxillofacial Surgery. - 0901-5027 .- 1399-0020.
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to assess if there is a time difference (operative time, ischemia time, planning time and hospitalization) between virtual surgical planning (VSP) and conventional planning in cranio-maxillofacial surgery (CMF). An electronic search was performed in June 2018. Studies comparing time difference between VSP and traditional planning were included. A meta-analysis was undertaken to demonstrate the difference between the groups regarding operative time, ischemia time and hospitalization duration for CMF reconstruction. 27 publications were included, with 524 patients in the VSP group and 770 in the control group. Most studies reported on mandible/maxilla reconstruction and the meta-analysis showed a decreased operative time for the VSP group with a mean difference of -84.61 min (95%CI -106.77, -62,45, p<0.00001). Ischemia time was also decreased, with a mean difference of -36.14 min (95% confidence interval -50.57, -21.71, p<0.00001). This systematic review and meta-analysis suggests that VSP is shortening the operation time and ischemia time for reconstructive CMF surgery. VSP also seems to shorten the preoperative planning time for orthognathic surgery.
|
|
| 9. |
- Nilsson, Johanna, et al.
(författare)
-
Virtual bite registration using intraoral digital scanning, CT and CBCT : In vitro evaluation of a new method and its implication for orthognathic surgery
- 2016
-
Ingår i: Journal of Cranio-Maxillofacial Surgery. - : Elsevier BV. - 1010-5182 .- 1878-4119. ; 44:9, s. 1194-1200
-
Tidskriftsartikel (refereegranskat)abstract
- Three-dimensional (3D) computer-assisted planning requires detailed visualisation of the craniomaxillofacial region and interocclusal relationship. The aim of this study was to establish and evaluate a method to create a 3D model of the craniomaxillofacial region and to adopt intraoral digital scanning to place the lower jaw into a centric relation (CR) without the need of additional plaster casts and model surgery. A standard plastic skull modified by metallic dental wires and brackets was subjected to computed tomography (CT), cone beam computed tomography (CBCT), and intraoral digital scanning. We evaluated two different virtual bite registrations, a digital scan of the buccal dental surfaces and scanning of the wax bites to position the lower jaw into a CR, and assessed the accuracy of the integration of intraoral scanning to the CT/CBCT scans. The mean registration error of corresponding mesh points for the CT and intraoral scanned images was 0.15 ± 0.12 mm, while this error was 0.18 ± 0.13 mm for the CBCT and intraoral scanned images. The mean accuracy of the two virtual bite registrations ranged from 0.41 to 0.49 mm (buccal scan technique) and from 0.65 to 1.3 mm (virtualised wax bite technique). A method for virtual bite registration was developed. It has the potential to eliminate plaster casts and model surgery and may facilitate 3D computer-assisted planning of orthognathic surgery cases.
|
|
| 10. |
- Nysjö, Johan, 1985-, et al.
(författare)
-
Rapid and Precise Orbit Segmentation through Interactive 3D Painting
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- In this paper, we present an efficient interactive tool for segmenting and measuring the volume of the bony orbit (eye-socket) in computed tomography (CT) images. The tool implements a 3D painting interface that allows the user to quickly segment or "paint" the fat and soft-tissue content of the orbit by sweeping a volumetric brush over the image. The brush modifies and updates the segmentation result in real-time and takes distance and gradient information into account to fill out and find the exact boundaries of the orbit. A smooth and consistent delineation of the anterior boundary is obtained by fitting a thin-plate spline to user-selected landmarks. We evaluate the tool on 10 CT images of intact and fractured orbits and show that it achieves high intra- and inter-operator precision (mean spatial overlap 95%, less than 1 ml volume variability) and produces segmentation results that are similar to manually corrected reference segmentations, but only requires a few minutes of interaction time.
|
|
