Oral and Maxillofacial Surgery for the Clinician, 2021
Successful implant dentistry mandates implants to be placed in an appropriate three-dimensional m... more Successful implant dentistry mandates implants to be placed in an appropriate three-dimensional manner that supports the prosthesis adequately. Due to the resorption patterns of edentulous jaws, the ideal position of implants required varying amounts of bone augmentation. Commonly carried out bone-augmentation procedures are Guided Bone Regeneration, onlay bone grafting and sinus floor elevation. This chapter discusses the resorption pattern of edentulous jaws, the biology of alveolar bone of relevance to the maxillofacial surgeon, the biomaterials used for augmentation and the commonly carried out augmentation procedures.
Oral and Maxillofacial Surgery for the Clinician, 2021
Over the past decades, implant dentistry has evolved to be a very predictable treatment modality ... more Over the past decades, implant dentistry has evolved to be a very predictable treatment modality for the replacement of lost teeth and has now become one of the most common oral surgical procedures carried out worldwide. This chapter introduces the history and evolution of dental implants, discusses the concept of osseointegration, mentions the types of implants and discusses clinical decision making and execution of straight forward implant placement. It must be noted that the field of implantology is rapidly developing with new treatment concepts and increasing use of digital technology. The surgical part of implant treatment although extremely important, is only a part of the overall treatment, the other important factors being the laboratory and prosthodontics. This chapter only provides a basic surgical overview of implantology for the beginner surgeon clinician.
Clinical Implant Dentistry and Related Research, 2016
Background and PurposeOsteoporosis is a major skeletal disease affecting millions of people world... more Background and PurposeOsteoporosis is a major skeletal disease affecting millions of people worldwide. Recent studies claim that patients with osteoporosis do not have a higher risk of early implant failure compared to non‐osteoporotic patients. The aim of this study was to assess the effect of skeletal osteoporosis and local bone density on initial dental implant stability.Materials and MethodsSeventy‐three patients were recruited and were assigned (based on a Dual‐energy X‐ray Absorptiometry scan) to either the osteoporosis (Opr), osteopenia (Opn), or control (C) group. Forty nine of the 73 patients received dental implants and had implant stability measured by means of resonance frequency analysis (RFA) at implant placement and at prosthetic abutment placement. On the computerized tomography scans, the cortical thickness and the bone density (Hounsfield Units) at the sites of implant placement were measured.ResultsAt implant placement, primary stability was on average lower in gr...
Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition tha... more Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition that can affect multiple organs. IgG4-RD may show a variety of initial symptoms. In the oral mucosa, lesions present as inflammatory fibrosis with a large number of IgG4-positive plasma cells. Evaluating treatment is a well-known problem in IgG4-RD due to the absence of an established assessment system. There are difficulties in defining the severity of the disease, which is why treatment is primarily based on its clinical manifestations. We present a case report of localized IgG4-RD with ulcerative and proliferative manifestations on the tongue, which clinically mimicked oral squamous cell carcinoma. A tumor-like lesion on the tongue can indicate something else other than the malignant or reactive changes commonly found in the oral mucosa. Multiple differential diagnoses of these atypical oral lesions, including localized IgG4-RD, should be considered.
International Journal of Computer Assisted Radiology and Surgery, 2021
Purpose The management of complex mandible fractures, i.e. severely comminuted or fractures of ed... more Purpose 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. Methods 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 cone beam computed tomography (CBCT) images of a plastic skull model and on twelve retrospective cases with complex mandible fractures. Resul...
In animal studies on bone healing, the effect of housing space and physical activity are seldom t... more In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean ± SEM BW: 3.9 ± 0.11 kg) with a critical bone defect after 12 weeks of rehabilitation in pair-housing in 3 m 2 large floor pens (Floor, n = 10) or standard single housing in 0.43 m 2 cages (Cage, n = 10). In the randomised full-factorial study, a bone replica of calcium phosphate cement (CPC, n = 10) or autologous bone (AB, n = 10) was implanted in the unilateral 20 mm radius defect. Post-mortem, the oxidative capacity was measured by citrate synthase (CS) activity in M. quadriceps and the defect filling volume and density evaluated by microcomputer tomography (μ-CT). Histology sections were evaluated by subjective scoring and histomorphometry. Fourteen rabbits remained until the end of the study. Group Floor (n = 7; 3 CPC + 4 AB) had a higher CS activity and a larger bone defect filling volume and lower density by μ-CT measurements than group Cage (n = 7; 3 CPC + 4 AB). Three out of four rabbits in AB-Floor presented fusion of the defect with reorganisation of trabecular bone, whereas three of four in AB-Cage showed areas of incomplete healing. Floor rabbits had a higher score of bony fusion between the radius and ulna than Cage rabbits. There were no differences between groups in histomorphometry. The study found that a larger housing space increased physical activity and promoted bone formation.
The International Journal of Oral & Maxillofacial Implants, 2019
Cone beam computed tomography (CBCT) is an important imaging technique in maxillofacial evaluatio... more Cone beam computed tomography (CBCT) is an important imaging technique in maxillofacial evaluations. However, application-specific image analysis methods aimed at extracting quantitative information from these images need to be further developed. The aim of this study was to provide a robust and objective method that could assess radiologic changes around dental implants after sinus elevation surgery with simultaneous implant placement. Materials and Methods: The study was performed retrospectively on patients fulfilling the inclusion criteria. The included patients had been CBCT scanned preoperatively, at baseline (early after surgery), and 6 months postoperatively. In order to quantify the radiologic changes, an image analysis workflow was developed based on the postoperative baseline and 6-month scans. The workflow included metal artifact reduction, registration, and a standardized protocol for semiautomatic segmentation. Validation of different steps of the method was conducted by comparing scans from all time points. Comparison of constant volumes (eg, screws and bony parts not subjected to change) was used. Additionally, the Dice similarity coefficient (DSC) was used to measure the overlap of the segmentations. Results: The study included nine maxillary sinuses from six patients. The bone formation was quantified and visualized in 3D. In the validation, no significant differences were found for the constant volumes at the different scanning time points. The DSC showed accurate results with values > 0.92. Conclusion: The method presented in this study provides an objective and robust evaluation of bone formation around dental implants. The same methodologies can be applied in other studies of dental CBCT images, eg, for comparison of grafting materials or surgical strategies.
Congenital granular cell epulis (CGCE) is an uncommon benign lesion found in newborns. It has pre... more Congenital granular cell epulis (CGCE) is an uncommon benign lesion found in newborns. It has predominance for females with an 8:1 ratio in relation to males and is exclusively encountered in the oral cavity. The most affected oral site is located around the canine/incisor region of the maxillary alveolar ridge, where the lesion arises from the soft tissue as a solitary pedunculated mass. CGCE's histogenesis remains obscure and controversial. We present a rare case of 2 separate CGCE lesions adjacent to each other measuring 23 Â 18 Â 10 and 15 Â 10 mm, positioned facially on the right maxillary alveolar process. The patient, a 2-day-old female newborn, did not experience any serious difficulty regarding breathing or deglutition. Complete surgical excision was the treatment of choice in this case, and the procedure was performed under both general and local anesthesia. Histologic and immunohistochemical analysis confirmed the diagnosis of CGCE. The patient showed satisfactory postoperative healing and excellent health at both the 10-day recall appointment and the 6-month follow-up.
Opinions expressed by CE authors are their own and may not reflect those of Dentistry Today. Ment... more Opinions expressed by CE authors are their own and may not reflect those of Dentistry Today. Mention of specific product names does not infer endorsement by Dentistry Today. Information contained in CE articles and courses is not a substitute for sound clinical judgment and accepted standards of care. Participants are urged to contact their state dental boards for continuing education requirements. Dentistry Today is an ADA CERP Recognized Provider.
of the implant crowns and the implants, healthy periimplant tissues, and maintained marginal bone... more of the implant crowns and the implants, healthy periimplant tissues, and maintained marginal bone level of the adjacent teeth. However, provisional crown loosening occurred frequently.
Introduction: Bone augmentation before treatment with endosseous implants is a common procedure f... more Introduction: Bone augmentation before treatment with endosseous implants is a common procedure for rehabilitation of the edentulous jaw. Both machined and surface modified implants have been used in one-stage and two-stage surgery protocols with varying results and survival rates. The influence of surface modification on the integration of implants has been documented in both non-grafted and grafted bone. The aim of this study was to compare the integration and stability of surface modified fluoridated vs. machined implants when placed simultaneously with an onlay bone graft. Material and methods: Eight rabbits were used in this study. A disc shaped bone graft was harvested from each side of the sagittal suture of the calvarial bone and fixed bi-cortically to the proximal tibial metaphysis by means of a dental implant, 9 mm long and 3.5 mm in diameter with a smooth machined surface as control and a blasted, fluoridated surface as test. Test and control sides were randomised. After a healing time of 8 weeks, the rabbits were sacrificed and the implants were removed en block for light microscopic analysis. Bone to implant contact (BIC) was registered as well as the amount of bone filling a rectangle indicating a region of interest (ROI) in the grafted area. Resonance frequency analysis (RFA) was conducted both at the time of surgery and at the end of the study. Results: Our results showed statistically significant differences in BIC within the grafted area and the total bone to implant contact between the test and control sides in favour of the surface modified implants. The bone area filling the threads within a region of interest showed no statistically significant difference between the test and control sides. RFA showed higher implant stability with significant differences at the time of sacrifice in favour of the fluoridated implants. Conclusion: Surface modified fluoridated implants showed a higher degree of osseointegration and stability in onlay bone grafts compared with control implants with machined surface texture.
We present a case where a patient sustained a tympanic plate fracture of the right side while che... more We present a case where a patient sustained a tympanic plate fracture of the right side while chewing a sandwich. Intense pain with temporomandibular joint (TMJ) symptoms such as restrained painful mouth opening and functional pain in full occlusion followed the incident and the fracture was diagnosed after ocular and CT-examination of the right external auditory canal. Non-ruptured soft tissue could be seen protruding into the external auditory canal and the size of the mass changed during movement of the TMJ. Treatment was not needed to resolve the situation and at 3-year follow-up the patient has no clinical symptoms.
Clinical Implant Dentistry and Related Research, 2011
Extensive atrophy of the alveolar process may require a bone-grafting procedure prior to implant ... more Extensive atrophy of the alveolar process may require a bone-grafting procedure prior to implant treatment. Autogenous bone grafts from the iliac crest, used as onlay block and particulate bone, have been used together with sinus-lift procedure in order to rehabilitate patients with extremely resorbed maxillae. However, there are to our knowledge no 5-year follow-up studies evaluating the extent of bone-level change in patients treated with respectively block and particulate autogenous bone grafts. The purpose of this prospective clinical study was to conduct a 5-year follow-up analysis with focus on bone-level alteration in block versus particulate onlay bone grafts. Fifteen out of originally 19 patients who were treated with iliac bone grafts and oral implants in the maxilla have been followed through the first 5 postoperative years. In a first study conducted on 19 patients, the role of platelet-rich plasma in conjunction with autogenous bone was evaluated. In this 5-year follow-up study, the marginal bone alterations have been documented at base line, 1 year and 5 years of loading to the nearest 0,1 mm at mesial and distal surfaces of the implants. Two implants were installed on each side of the midline in either block or particulate bone grafts giving test and control sides in each patient. Additionally, two implants on each side were installed in residual bone/grafted sinus floor. Marginal bone alteration in the anterior maxilla appeared larger at the side augmented by block bone at baseline, and after 1 and 5 years of loading, but the change was not statistically significant. Moreover, there was a significantly higher degree of marginal alteration during the first year of loading, compared with the examinations after 5 years. The present follow-up study showed that there is no significant difference in the extension of resorption between block- and particulate autogenous bone grafts over a 5-year period. Most of the resorption occurred during the first year in function.
British Journal of Oral and Maxillofacial Surgery, 2013
Our aim was to evaluate the treatment given to patients with intraosseus ameloblastomas with spec... more 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.
With the increasing use of three-dimensional (3D) models and Computer Aided Design (CAD) in the m... more With the increasing use of three-dimensional (3D) models and Computer Aided Design (CAD) in the medical domain, virtual surgical planning is now frequently used. Most of the current solutions focus on bone surgical operations. However, for head and neck oncologic resection, soft tissue ablation and reconstruction are common operations. In this paper, we propose a method to provide a fast and efficient estimation of shape and dimensions of soft tissue resections. Our approach takes advantage of a simple sketch-based interface which allows the user to paint the contour of the resection on a patient specific 3D model reconstructed from a computed tomography (CT) scan. The volume is then virtually cut and carved following this pattern. From the outline of the resection defined on the skin surface as a closed curve, we can identify which areas of the skin are inside or outside this shape. We then use distance transforms to identify the soft tissue voxels which are closer from the inside ...
Background: Oral squamous cell carcinoma is the main malignancy of the oral cavity; floor of the ... more Background: Oral squamous cell carcinoma is the main malignancy of the oral cavity; floor of the mouth and the lateral border of the tongue being the most affected sites. This kind of oral neoplasms may require mandibular resection and reconstruction. Treatment options for such mandibular defects include bone grafts, free flaps, and reconstruction plates. Today, the commonly used treatment method is vascularized fibula flaps due to its many advantages when compared to other methods. However, it is a complex procedure and demands much of both practitioners and the patient. Case Presentation: In this report, we present a case of oral squamous cell carcinoma of the gingiva of the mandible which was treated with a partial mandibulectomy and resection. Because of the patients age and fragility an immediate mandibular reconstruction with a pre-shaped reconstruction plate, without hard or soft tissue transfer, was performed. Yearly controls showed pleasing results both aesthetically and fu...
A case of a blowout fracture with sever post traumatic emphysema is described in this study. The ... more A case of a blowout fracture with sever post traumatic emphysema is described in this study. The clinical presentation, diagnosis and management of orbital emphysema associated with blowout fractures are discussed, and the literature reviewed. This case highlights the importance of proper diagnostic measures and necessary treatment when dealing with orbital trauma patients. The clinical examination of motility, visual acuity and pupillary affect are primarily the most important factors of deciding suitable therapy. In an emergency, time is of the essence to reduce the risk of permanent vision loss.
International Journal of Oral and Maxillofacial Surgery, 2007
Injuries to the larynx (voice box) can lead to loss of vital functions; the airway may be obstruc... more Injuries to the larynx (voice box) can lead to loss of vital functions; the airway may be obstructed, the voice distorted or lost, and the protection of the airway during swallowing may fail. In order to preserve these functions, a stable repair that restores the anatomy as closely as possible is needed. The repair should interfere minimally with the neuromuscular functions of the larynx. The case is described of a 59-year-old male who suffered a severe laryngeal fracture in a work-place accident. Utilizing miniplates, the fracture was reduced and fixed in the correct position. After healing, the patient could be decannulated and has regained his voice, swallows without difficulty and has a patent airway. The results have been sustained over a 2-year follow-up.
To evaluate oral health related quality of life (OHQoL) in edentulous patients treated with immed... more To evaluate oral health related quality of life (OHQoL) in edentulous patients treated with immediately loaded implants in the maxilla. Fifty-one edentulous patients in two centers received six maxillary implants each were loaded within 24 h with provisional restoration. Definitive restoration was delivered 20-24 weeks later. OHQoL was evaluated preoperatively with the Oral Health Impact Profile 49 questionnaire (OHIP-49) and on five subsequent occasions. OHIP-49 includes seven domains representing functional limitation, physical pain, psychological discomfort, physical disability, psychological disability, social disability, and handicap. A reduction in OHIP scores indicated an improved OHQoL. Forty-five patients reached the three-year follow up. OHQoL improved after treatment. A plateau of OHQoL improvement was observed at 12 months after surgery. The seven domains improved at different pace, 12 weeks to 12 months after treatment. OHIP showed continuously low scores with no signif...
Several studies have evaluated accuracy of intraoral scanners (IOS), but data is lacking regardin... more Several studies have evaluated accuracy of intraoral scanners (IOS), but data is lacking regarding variations between IOS systems in the depiction of the critical finish line and the finish line accuracy. The aim of this study was to analyze the level of finish line distinctness (FLD), and finish line accuracy (FLA), in 7 intraoral scanners (IOS) and one conventional impression (IMPR). Furthermore, to assess parameters of resolution, tessellation, topography, and color. A dental model with a crown preparation including supra and subgingival finish line was reference-scanned with an industrial scanner (ATOS), and scanned with seven IOS: 3M, CS3500 and CS3600, DWIO, Omnicam, Planscan and Trios. An IMPR was taken and poured, and the model was scanned with a laboratory scanner. The ATOS scan was cropped at finish line and best-fit aligned for 3D Compare Analysis (Geomagic). Accuracy was visualized, and descriptive analysis was performed. All IOS, except Planscan, had comparable overall ...
Oral and Maxillofacial Surgery for the Clinician, 2021
Successful implant dentistry mandates implants to be placed in an appropriate three-dimensional m... more Successful implant dentistry mandates implants to be placed in an appropriate three-dimensional manner that supports the prosthesis adequately. Due to the resorption patterns of edentulous jaws, the ideal position of implants required varying amounts of bone augmentation. Commonly carried out bone-augmentation procedures are Guided Bone Regeneration, onlay bone grafting and sinus floor elevation. This chapter discusses the resorption pattern of edentulous jaws, the biology of alveolar bone of relevance to the maxillofacial surgeon, the biomaterials used for augmentation and the commonly carried out augmentation procedures.
Oral and Maxillofacial Surgery for the Clinician, 2021
Over the past decades, implant dentistry has evolved to be a very predictable treatment modality ... more Over the past decades, implant dentistry has evolved to be a very predictable treatment modality for the replacement of lost teeth and has now become one of the most common oral surgical procedures carried out worldwide. This chapter introduces the history and evolution of dental implants, discusses the concept of osseointegration, mentions the types of implants and discusses clinical decision making and execution of straight forward implant placement. It must be noted that the field of implantology is rapidly developing with new treatment concepts and increasing use of digital technology. The surgical part of implant treatment although extremely important, is only a part of the overall treatment, the other important factors being the laboratory and prosthodontics. This chapter only provides a basic surgical overview of implantology for the beginner surgeon clinician.
Clinical Implant Dentistry and Related Research, 2016
Background and PurposeOsteoporosis is a major skeletal disease affecting millions of people world... more Background and PurposeOsteoporosis is a major skeletal disease affecting millions of people worldwide. Recent studies claim that patients with osteoporosis do not have a higher risk of early implant failure compared to non‐osteoporotic patients. The aim of this study was to assess the effect of skeletal osteoporosis and local bone density on initial dental implant stability.Materials and MethodsSeventy‐three patients were recruited and were assigned (based on a Dual‐energy X‐ray Absorptiometry scan) to either the osteoporosis (Opr), osteopenia (Opn), or control (C) group. Forty nine of the 73 patients received dental implants and had implant stability measured by means of resonance frequency analysis (RFA) at implant placement and at prosthetic abutment placement. On the computerized tomography scans, the cortical thickness and the bone density (Hounsfield Units) at the sites of implant placement were measured.ResultsAt implant placement, primary stability was on average lower in gr...
Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition tha... more Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition that can affect multiple organs. IgG4-RD may show a variety of initial symptoms. In the oral mucosa, lesions present as inflammatory fibrosis with a large number of IgG4-positive plasma cells. Evaluating treatment is a well-known problem in IgG4-RD due to the absence of an established assessment system. There are difficulties in defining the severity of the disease, which is why treatment is primarily based on its clinical manifestations. We present a case report of localized IgG4-RD with ulcerative and proliferative manifestations on the tongue, which clinically mimicked oral squamous cell carcinoma. A tumor-like lesion on the tongue can indicate something else other than the malignant or reactive changes commonly found in the oral mucosa. Multiple differential diagnoses of these atypical oral lesions, including localized IgG4-RD, should be considered.
International Journal of Computer Assisted Radiology and Surgery, 2021
Purpose The management of complex mandible fractures, i.e. severely comminuted or fractures of ed... more Purpose 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. Methods 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 cone beam computed tomography (CBCT) images of a plastic skull model and on twelve retrospective cases with complex mandible fractures. Resul...
In animal studies on bone healing, the effect of housing space and physical activity are seldom t... more In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean ± SEM BW: 3.9 ± 0.11 kg) with a critical bone defect after 12 weeks of rehabilitation in pair-housing in 3 m 2 large floor pens (Floor, n = 10) or standard single housing in 0.43 m 2 cages (Cage, n = 10). In the randomised full-factorial study, a bone replica of calcium phosphate cement (CPC, n = 10) or autologous bone (AB, n = 10) was implanted in the unilateral 20 mm radius defect. Post-mortem, the oxidative capacity was measured by citrate synthase (CS) activity in M. quadriceps and the defect filling volume and density evaluated by microcomputer tomography (μ-CT). Histology sections were evaluated by subjective scoring and histomorphometry. Fourteen rabbits remained until the end of the study. Group Floor (n = 7; 3 CPC + 4 AB) had a higher CS activity and a larger bone defect filling volume and lower density by μ-CT measurements than group Cage (n = 7; 3 CPC + 4 AB). Three out of four rabbits in AB-Floor presented fusion of the defect with reorganisation of trabecular bone, whereas three of four in AB-Cage showed areas of incomplete healing. Floor rabbits had a higher score of bony fusion between the radius and ulna than Cage rabbits. There were no differences between groups in histomorphometry. The study found that a larger housing space increased physical activity and promoted bone formation.
The International Journal of Oral & Maxillofacial Implants, 2019
Cone beam computed tomography (CBCT) is an important imaging technique in maxillofacial evaluatio... more Cone beam computed tomography (CBCT) is an important imaging technique in maxillofacial evaluations. However, application-specific image analysis methods aimed at extracting quantitative information from these images need to be further developed. The aim of this study was to provide a robust and objective method that could assess radiologic changes around dental implants after sinus elevation surgery with simultaneous implant placement. Materials and Methods: The study was performed retrospectively on patients fulfilling the inclusion criteria. The included patients had been CBCT scanned preoperatively, at baseline (early after surgery), and 6 months postoperatively. In order to quantify the radiologic changes, an image analysis workflow was developed based on the postoperative baseline and 6-month scans. The workflow included metal artifact reduction, registration, and a standardized protocol for semiautomatic segmentation. Validation of different steps of the method was conducted by comparing scans from all time points. Comparison of constant volumes (eg, screws and bony parts not subjected to change) was used. Additionally, the Dice similarity coefficient (DSC) was used to measure the overlap of the segmentations. Results: The study included nine maxillary sinuses from six patients. The bone formation was quantified and visualized in 3D. In the validation, no significant differences were found for the constant volumes at the different scanning time points. The DSC showed accurate results with values > 0.92. Conclusion: The method presented in this study provides an objective and robust evaluation of bone formation around dental implants. The same methodologies can be applied in other studies of dental CBCT images, eg, for comparison of grafting materials or surgical strategies.
Congenital granular cell epulis (CGCE) is an uncommon benign lesion found in newborns. It has pre... more Congenital granular cell epulis (CGCE) is an uncommon benign lesion found in newborns. It has predominance for females with an 8:1 ratio in relation to males and is exclusively encountered in the oral cavity. The most affected oral site is located around the canine/incisor region of the maxillary alveolar ridge, where the lesion arises from the soft tissue as a solitary pedunculated mass. CGCE's histogenesis remains obscure and controversial. We present a rare case of 2 separate CGCE lesions adjacent to each other measuring 23 Â 18 Â 10 and 15 Â 10 mm, positioned facially on the right maxillary alveolar process. The patient, a 2-day-old female newborn, did not experience any serious difficulty regarding breathing or deglutition. Complete surgical excision was the treatment of choice in this case, and the procedure was performed under both general and local anesthesia. Histologic and immunohistochemical analysis confirmed the diagnosis of CGCE. The patient showed satisfactory postoperative healing and excellent health at both the 10-day recall appointment and the 6-month follow-up.
Opinions expressed by CE authors are their own and may not reflect those of Dentistry Today. Ment... more Opinions expressed by CE authors are their own and may not reflect those of Dentistry Today. Mention of specific product names does not infer endorsement by Dentistry Today. Information contained in CE articles and courses is not a substitute for sound clinical judgment and accepted standards of care. Participants are urged to contact their state dental boards for continuing education requirements. Dentistry Today is an ADA CERP Recognized Provider.
of the implant crowns and the implants, healthy periimplant tissues, and maintained marginal bone... more of the implant crowns and the implants, healthy periimplant tissues, and maintained marginal bone level of the adjacent teeth. However, provisional crown loosening occurred frequently.
Introduction: Bone augmentation before treatment with endosseous implants is a common procedure f... more Introduction: Bone augmentation before treatment with endosseous implants is a common procedure for rehabilitation of the edentulous jaw. Both machined and surface modified implants have been used in one-stage and two-stage surgery protocols with varying results and survival rates. The influence of surface modification on the integration of implants has been documented in both non-grafted and grafted bone. The aim of this study was to compare the integration and stability of surface modified fluoridated vs. machined implants when placed simultaneously with an onlay bone graft. Material and methods: Eight rabbits were used in this study. A disc shaped bone graft was harvested from each side of the sagittal suture of the calvarial bone and fixed bi-cortically to the proximal tibial metaphysis by means of a dental implant, 9 mm long and 3.5 mm in diameter with a smooth machined surface as control and a blasted, fluoridated surface as test. Test and control sides were randomised. After a healing time of 8 weeks, the rabbits were sacrificed and the implants were removed en block for light microscopic analysis. Bone to implant contact (BIC) was registered as well as the amount of bone filling a rectangle indicating a region of interest (ROI) in the grafted area. Resonance frequency analysis (RFA) was conducted both at the time of surgery and at the end of the study. Results: Our results showed statistically significant differences in BIC within the grafted area and the total bone to implant contact between the test and control sides in favour of the surface modified implants. The bone area filling the threads within a region of interest showed no statistically significant difference between the test and control sides. RFA showed higher implant stability with significant differences at the time of sacrifice in favour of the fluoridated implants. Conclusion: Surface modified fluoridated implants showed a higher degree of osseointegration and stability in onlay bone grafts compared with control implants with machined surface texture.
We present a case where a patient sustained a tympanic plate fracture of the right side while che... more We present a case where a patient sustained a tympanic plate fracture of the right side while chewing a sandwich. Intense pain with temporomandibular joint (TMJ) symptoms such as restrained painful mouth opening and functional pain in full occlusion followed the incident and the fracture was diagnosed after ocular and CT-examination of the right external auditory canal. Non-ruptured soft tissue could be seen protruding into the external auditory canal and the size of the mass changed during movement of the TMJ. Treatment was not needed to resolve the situation and at 3-year follow-up the patient has no clinical symptoms.
Clinical Implant Dentistry and Related Research, 2011
Extensive atrophy of the alveolar process may require a bone-grafting procedure prior to implant ... more Extensive atrophy of the alveolar process may require a bone-grafting procedure prior to implant treatment. Autogenous bone grafts from the iliac crest, used as onlay block and particulate bone, have been used together with sinus-lift procedure in order to rehabilitate patients with extremely resorbed maxillae. However, there are to our knowledge no 5-year follow-up studies evaluating the extent of bone-level change in patients treated with respectively block and particulate autogenous bone grafts. The purpose of this prospective clinical study was to conduct a 5-year follow-up analysis with focus on bone-level alteration in block versus particulate onlay bone grafts. Fifteen out of originally 19 patients who were treated with iliac bone grafts and oral implants in the maxilla have been followed through the first 5 postoperative years. In a first study conducted on 19 patients, the role of platelet-rich plasma in conjunction with autogenous bone was evaluated. In this 5-year follow-up study, the marginal bone alterations have been documented at base line, 1 year and 5 years of loading to the nearest 0,1 mm at mesial and distal surfaces of the implants. Two implants were installed on each side of the midline in either block or particulate bone grafts giving test and control sides in each patient. Additionally, two implants on each side were installed in residual bone/grafted sinus floor. Marginal bone alteration in the anterior maxilla appeared larger at the side augmented by block bone at baseline, and after 1 and 5 years of loading, but the change was not statistically significant. Moreover, there was a significantly higher degree of marginal alteration during the first year of loading, compared with the examinations after 5 years. The present follow-up study showed that there is no significant difference in the extension of resorption between block- and particulate autogenous bone grafts over a 5-year period. Most of the resorption occurred during the first year in function.
British Journal of Oral and Maxillofacial Surgery, 2013
Our aim was to evaluate the treatment given to patients with intraosseus ameloblastomas with spec... more 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.
With the increasing use of three-dimensional (3D) models and Computer Aided Design (CAD) in the m... more With the increasing use of three-dimensional (3D) models and Computer Aided Design (CAD) in the medical domain, virtual surgical planning is now frequently used. Most of the current solutions focus on bone surgical operations. However, for head and neck oncologic resection, soft tissue ablation and reconstruction are common operations. In this paper, we propose a method to provide a fast and efficient estimation of shape and dimensions of soft tissue resections. Our approach takes advantage of a simple sketch-based interface which allows the user to paint the contour of the resection on a patient specific 3D model reconstructed from a computed tomography (CT) scan. The volume is then virtually cut and carved following this pattern. From the outline of the resection defined on the skin surface as a closed curve, we can identify which areas of the skin are inside or outside this shape. We then use distance transforms to identify the soft tissue voxels which are closer from the inside ...
Background: Oral squamous cell carcinoma is the main malignancy of the oral cavity; floor of the ... more Background: Oral squamous cell carcinoma is the main malignancy of the oral cavity; floor of the mouth and the lateral border of the tongue being the most affected sites. This kind of oral neoplasms may require mandibular resection and reconstruction. Treatment options for such mandibular defects include bone grafts, free flaps, and reconstruction plates. Today, the commonly used treatment method is vascularized fibula flaps due to its many advantages when compared to other methods. However, it is a complex procedure and demands much of both practitioners and the patient. Case Presentation: In this report, we present a case of oral squamous cell carcinoma of the gingiva of the mandible which was treated with a partial mandibulectomy and resection. Because of the patients age and fragility an immediate mandibular reconstruction with a pre-shaped reconstruction plate, without hard or soft tissue transfer, was performed. Yearly controls showed pleasing results both aesthetically and fu...
A case of a blowout fracture with sever post traumatic emphysema is described in this study. The ... more A case of a blowout fracture with sever post traumatic emphysema is described in this study. The clinical presentation, diagnosis and management of orbital emphysema associated with blowout fractures are discussed, and the literature reviewed. This case highlights the importance of proper diagnostic measures and necessary treatment when dealing with orbital trauma patients. The clinical examination of motility, visual acuity and pupillary affect are primarily the most important factors of deciding suitable therapy. In an emergency, time is of the essence to reduce the risk of permanent vision loss.
International Journal of Oral and Maxillofacial Surgery, 2007
Injuries to the larynx (voice box) can lead to loss of vital functions; the airway may be obstruc... more Injuries to the larynx (voice box) can lead to loss of vital functions; the airway may be obstructed, the voice distorted or lost, and the protection of the airway during swallowing may fail. In order to preserve these functions, a stable repair that restores the anatomy as closely as possible is needed. The repair should interfere minimally with the neuromuscular functions of the larynx. The case is described of a 59-year-old male who suffered a severe laryngeal fracture in a work-place accident. Utilizing miniplates, the fracture was reduced and fixed in the correct position. After healing, the patient could be decannulated and has regained his voice, swallows without difficulty and has a patent airway. The results have been sustained over a 2-year follow-up.
To evaluate oral health related quality of life (OHQoL) in edentulous patients treated with immed... more To evaluate oral health related quality of life (OHQoL) in edentulous patients treated with immediately loaded implants in the maxilla. Fifty-one edentulous patients in two centers received six maxillary implants each were loaded within 24 h with provisional restoration. Definitive restoration was delivered 20-24 weeks later. OHQoL was evaluated preoperatively with the Oral Health Impact Profile 49 questionnaire (OHIP-49) and on five subsequent occasions. OHIP-49 includes seven domains representing functional limitation, physical pain, psychological discomfort, physical disability, psychological disability, social disability, and handicap. A reduction in OHIP scores indicated an improved OHQoL. Forty-five patients reached the three-year follow up. OHQoL improved after treatment. A plateau of OHQoL improvement was observed at 12 months after surgery. The seven domains improved at different pace, 12 weeks to 12 months after treatment. OHIP showed continuously low scores with no signif...
Several studies have evaluated accuracy of intraoral scanners (IOS), but data is lacking regardin... more Several studies have evaluated accuracy of intraoral scanners (IOS), but data is lacking regarding variations between IOS systems in the depiction of the critical finish line and the finish line accuracy. The aim of this study was to analyze the level of finish line distinctness (FLD), and finish line accuracy (FLA), in 7 intraoral scanners (IOS) and one conventional impression (IMPR). Furthermore, to assess parameters of resolution, tessellation, topography, and color. A dental model with a crown preparation including supra and subgingival finish line was reference-scanned with an industrial scanner (ATOS), and scanned with seven IOS: 3M, CS3500 and CS3600, DWIO, Omnicam, Planscan and Trios. An IMPR was taken and poured, and the model was scanned with a laboratory scanner. The ATOS scan was cropped at finish line and best-fit aligned for 3D Compare Analysis (Geomagic). Accuracy was visualized, and descriptive analysis was performed. All IOS, except Planscan, had comparable overall ...
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Papers by Andreas Thor