Includes bibliographical references. / Use of perforators as recipient vessels in microvascular reconstruction has led to arterial diameter discrepancy becoming an increasingly common finding. Experimental and clinical evidence confirms that patency rates decrease with increasing diameter mismatch, but no good evidence is available to direct the choice of end-to-end microanastomotic technique where a small-to-large discrepancy exists. A programme of research has been conducted comparing two techniques of endto-end arterial microanastomoses, where a small-to-large diameter discrepancy exists of between 1:1.5 and 1:2.5. These techniques are; 45º oblique section of the smaller vessel, and; invaginating the smaller vessel inside the larger.

Includes references. / Despite the success of negative-pressure wound therapy, its mechanism of action remains unclear. The common perception that it reduces tissue pressure and increases perfusion has recently been challenged following the observation that tissue necrosis can be caused as a result of its application. A programme of research has been conducted to clarify how tissue pressure changes during negative-pressure wound therapy and the resultant effect thereof on perfusion. The cause for conflicting evidence from other studies was also investigated.

Background: Maxillary defects caused by trauma or tumour resection in the head and neck region can be devastating to the patient from a cosmetic and functional perspective. Patients who undergo maxillectomy procedures experience a substantial deterioration in their primary oral functions such as breathing, mastication, salivation, deglutition and phonation, which has a collective adverse influence on their quality of life (QOL). The revascularised free fibula flap (RFFF) has been demonstrated to be most reliable for the reconstruction of maxillary defects, and has been regarded as the 'gold standard.' A novel method of regenerating bone and soft tissue through the process of curvilinear transport distraction oseteogenesis (CTDO) has been developed and compared with the RFFF technique. Method: A prospective cohort study of 6 post-maxillectomy patients was compared regarding the clinical outcome of function and aesthetics with a group of 6 patients who had undergone RFFF reconstruction. The new bone (regenerate) was compared with the parent bone from which it had been generated. Objective measuring tools were employed to assess pre and post quality of life (QOL) aspects. The RFFF patients were not subjected to any invasive procedures save to undergo a clinical evaluation and undergo a CT scan of their maxillae. A cohort of 6 participants was treated prospectively using CTDO and the results were analysed within that cohort. These results were compared with a retrospective group of 6 participants of similar age and gender distribution who had undergone RFFF reconstruction as an external control. The patented Hendricks-Vicatos (H-V) maxillary transport distractor was applied to all selected participants by the primary investigator under general anaesthesia at Groote Schuur Hospital or a private clinic. The H-V maxillary transport distractor (5 prototypes) was pre-shaped and pre-fitted onto a 3-D model of the participant's maxilla, in a laboratory. This method reduced clinical installation time. If teeth were present in the area to be distracted, then at least 2 teeth were removed from the maxilla, preferably three months before the date of distraction. In the first few cases, this was the protocol for developing bone stock. This protocol was revised in the last 2 patients of the study, where no teeth were extracted at all. A linear fracture (bi-cortical) was created in the maxilla in a vertical direction (segmentally) to develop a mobile, well-vascularised transport disc. This carrier disc was attached to the metal plate of the 'crawler' via small titanium screws. The crawler was then moved on the reconstruction plate (BiometTM Zimmer Biomet,

Propofol has been gaining increased attention as a sole agent in providing procedural sedation due to its predictable pharmacokinetics and favorable amnestic properties. Oral and maxillofacial surgical procedures are unique in duration and concomitant use of local anesthesia making it difficult to evaluate data obtained from other specialties. The purpose of our study is to evaluate the safety, efficacy and satisfaction among surgeons and patients using propofol only, for procedural sedation during the extraction of third molars. Propofol 10mg/ml was administered using an induction dose of 0.5 to 1mg/kg over 60 seconds followed by bolus doses of 10 – 20mg every minute to achieve a Ramsay sedation score of at least 3. Respiratory compromise was identified in 15% of patients. Hemodynamic compromise was identified in 15%. Patient and surgeon satisfaction was high however propofol does not represent the ideal drug as a sole agent for procedural sedation in oral surgery due to the frequent need for hand restraint (40%).

Magister Chirurgiae Dentium (MChD) / Introduction: A common complication of poorly managed mandible fractures is infection. There is a consensus amongst clinicians in treating infected mandible fractures in an immediate setting. The approach includes drainage of the purulent discharge, debridement of the fracture, removal of teeth in the fracture line and immediate fixation. Fixation can be load bearing or load sharing in nature. Although clinicians advocate for the use of a reconstruction load bearing plate, a double miniplate fixation could be an alternative. Aim: The aim is to assess the outcomes of double miniplate osteosynthesis in the immediate management of infected mandible fractures Material and method: A prospective cohort study was conducted. The sample size was 20 (n =20). Infections were treated with an incision and drainage and the fractures fixated with a double miniplate fixation system. Pain scores, fracture union, fracture stability and surgical times were measured. Follow–up visits included one week, six weeks and three months respectively. Results: Mandibular angle fractures were most commonly infected. The most common cause of infection were teeth in the line of fracture. The buccal fascial space was the most commonly involved fascial space in regard to spread of infection. Nineteen of the twenty cases attained fracture stability. However, complications commonly encountered were persistent infection and wound dehiscence. Conclusion: Although a limited number of clinical cases were treated, the results correspond with the current literature when an immediate miniplate fixation protocol is used in infected mandible fractures. However, complications encountered in the study included the persistence of infection and wound dehiscence.

Syfte: Att systematiskt sammanfatta litteraturen inom området för medicinska behandlingsalternativ för icke-infektiös, kronisk osteomyelit i käkarna, utvärderat genom utläkning i ben och smärtlindring. Metod: En systematisk litteraturöversikt gjordes i fyra databaser; PubMed, Cochrane Library, Web of Science och Scopus. Översikten utfördes enligt instruktioner från ”PRISMA checklist” och ”CRD’s guidance”. En kvalitetsbedömning gjordes av samtliga inkluderade publikationer.Resultat: Sökningen resulterade i 2 100 artiklar. Efter urvalsprocessen återstod tre artiklar som inkluderades i denna systematiska litteraturöversikt. Samtliga studier utvärderade olika typer av bisfosfonatbehandlingar – ibandronat, pamidronat och disodium clodronat. Den smärtlindrande effekten utvärderades i alla tre studierna och utläkningen av benet utvärderades i två av artiklarna. Konklusion: Behandling av icke-infektiös osteomyelit med bisfosfonater visar en reduktion av smärta. Dock är den smärtlindrande effekten beroende på typen av bisfosfonat. Resultaten gällande utläkningen av ben är tvetydiga och därför kan ingen konklusion gällande detta göras. Endast en artikel ansågs i kvalitetsgranskningen ha hög kvalitet. För att kunna ta fram tydliga, evidensbaserade riktlinjer gällande behandling av icke-infektiös osteomyelit behövs fler kliniska studier som håller hög kvalitet. Bisfosfonater verkar vara ett bra behandlingsalternativ av icke-infektiös osteomyelit. Ett alternativ till bisfosfonater, skulle kunna vara behandling med denosumab, som har liknande verkningsmekanism men kortare halveringstid. Dock krävs fortsatta studier inom detta område. / Aim: To systematically review the literature of medical treatment alternatives of non-infectious chronic osteomyelitis in the jaws regarding bone healing and pain relief. Methods: A systematic literature search has been made in four databases; PubMed, Cochrane Library, Web of Science and Scopus. The review was performed with directions from the PRISMA checklist and CRD’s guidance. A quality assessment was made of the included studies.Results: The search resulted in 2 100 articles and after the selection process, only three articles were included in this review. The studies evaluated different types of bisphosphonates - ibandronate, pamidronate and disodium clodronate. The reduction of pain was evaluated in all three articles and the bone healing was assessed in two of the articles. Conclusion: Treatment of non-infectious osteomyelitis with bisphosphonates shows a reduction in pain. However, the pain-relieving effect is most probably dependent on the type of bisphosphonates. The results of bone healing assessed from Tc-scans are ambiguous and therefore no conclusion can be made. Only one article in this review was considered to have high quality in the quality assessment. To enable clear guidelines regarding treatment of non-infectious osteomyelitis, more clinical trials with high quality is desirable. In summary, bisphosphonates seem to be a good alternative in treatment of non-infectious osteomyelitis. An alternative to bisphosphonates might be treatment with denosumab, which have a similar mechanism of action but shorter half-life. However, further research is needed.

Syfte: Att systematiskt sammanfatta litteraturen inom området för medicinska behandlingsalternativ för icke-infektiös, kronisk osteomyelit i käkarna, utvärderat genom utläkning i ben och smärtlindring. Metod: En systematisk litteraturöversikt gjordes i fyra databaser; PubMed, Cochrane Library, Web of Science och Scopus. Översikten utfördes enligt instruktioner från ”PRISMA checklist” och ”CRD’s guidance”. En kvalitetsbedömning gjordes av samtliga inkluderade publikationer.Resultat: Sökningen resulterade i 2 100 artiklar. Efter urvalsprocessen återstod tre artiklar som inkluderades i denna systematiska litteraturöversikt. Samtliga studier utvärderade olika typer av bisfosfonatbehandlingar – ibandronat, pamidronat och disodium clodronat. Den smärtlindrande effekten utvärderades i alla tre studierna och utläkningen av benet utvärderades i två av artiklarna. Konklusion: Behandling av icke-infektiös osteomyelit med bisfosfonater visar en reduktion av smärta. Dock är den smärtlindrande effekten beroende på typen av bisfosfonat. Resultaten gällande utläkningen av ben är tvetydiga och därför kan ingen konklusion gällande detta göras. Endast en artikel ansågs i kvalitetsgranskningen ha hög kvalitet. För att kunna ta fram tydliga, evidensbaserade riktlinjer gällande behandling av icke-infektiös osteomyelit behövs fler kliniska studier som håller hög kvalitet. Bisfosfonater verkar vara ett bra behandlingsalternativ av icke-infektiös osteomyelit. Ett alternativ till bisfosfonater, skulle kunna vara behandling med denosumab, som har liknande verkningsmekanism men kortare halveringstid. Dock krävs fortsatta studier inom detta område. / Aim: To systematically review the literature of medical treatment alternatives of non-infectious chronic osteomyelitis in the jaws regarding bone healing and pain relief. Methods: A systematic literature search has been made in four databases; PubMed, Cochrane Library, Web of Science and Scopus. The review was performed with directions from the PRISMA checklist and CRD’s guidance. A quality assessment was made of the included studies.Results: The search resulted in 2 100 articles and after the selection process, only three articles were included in this review. The studies evaluated different types of bisphosphonates - ibandronate, pamidronate and disodium clodronate. The reduction of pain was evaluated in all three articles and the bone healing was assessed in two of the articles. Conclusion: Treatment of non-infectious osteomyelitis with bisphosphonates shows a reduction in pain. However, the pain-relieving effect is most probably dependent on the type of bisphosphonates. The results of bone healing assessed from Tc-scans are ambiguous and therefore no conclusion can be made. Only one article in this review was considered to have high quality in the quality assessment. To enable clear guidelines regarding treatment of non-infectious osteomyelitis, more clinical trials with high quality is desirable. In summary, bisphosphonates seem to be a good alternative in treatment of non-infectious osteomyelitis. An alternative to bisphosphonates might be treatment with denosumab, which have a similar mechanism of action but shorter half-life. However, further research is needed.

Introduction: An absolute majority of dental infections are treated without major complications. In exceptional situations dental infections can spread to surrounding structures such as the airways or even the brain leading to a life-threatening condition that requires hospitalization. According to literature, some qualified risk factors appear to be common in hospitalized patients. Aim: To outline factors typically seen in patients with acute maxillofacial infections with dental origin at Norrland University Hospital (NUS) and find possible association between these factors and the length of hospital stay.  Methods: A literature review using keywords associated with dental infections and acute throat and head infections was performed. Retrospective structured medical journal reviews of 58 patients suffering from acute maxillofacial infections which required hospitalization at NUS were analyzed. The results were analyzed using IBM SPSS Statistics software and Microsoft Office Excel. Results: The results indicated that overweight/obese people (Body Mass Index ⊵25) require longer care at the hospital due to their infection. Every other of the hospitalized patients had received dental treatment within 14 days prior to hospitalization.  Conclusions: In situations with acute maxillofacial infections of dental origin requiring hospitalization, BMI ⊵25 is eventually a risk factor. A group of patients received dental treatment for their infection, but the infection still exacerbated. How come? This requires deeper analysis with further studies.

Ce travail de thèse traite du développement d’une maille en titane imprimée en 3D pour le comblement des grands défauts osseux. La perte de substance osseuse intervient lors de traumatismes importants ou de chirurgies ablatives (dues à des infections ou à des cancers). Lorsque le défaut atteint un stade critique, la régénération osseuse est impossible et on assiste à une perte de fonction. Il faut alors recourir à des chirurgies reconstructrices comme par exemple la reconstruction mandibulaire. Aujourd’hui, la chirurgie communément pratiquée pour reconstruire la mandibule est la reconstruction par lambeaux libres de fibula, laquelle demande un investissement en temps et en ressource colossale pour des résultats mitigés avoisinant les 10% de taux d’échec. En nous basant sur la littérature internationale, nous avons développé une maille en titane imprimée en 3D pour remplacer l’autogreffe de fibula et ainsi limiter les effets secondaires liés au site donneur tout en offrant aux cellules mésenchymateuses des conditions optimales à la colonisation osseuse. D’un point de vue mécanique, cela consiste à abaisser la rigidité native du titane (110GPa) à une rigidité comprise entre 0,1 et 1 GPa. Pour réaliser cette maille, nous avons mis en place une méthodologie de design qui nous a permis d’innover en mettant au point un système de reprise de charge. Ce système de reprise de charge permet d’adapter la réponse de l’implant en fonction de l’intensité de la sollicitation, ce qui permet de combiner une rigidité faible et une résistance à l’effort élevée. Les différentes itérations de design ont été testées par éléments finis, jusqu’au motif final, lequel a été caractérisée lors de tests mécaniques réels en compression, en traction et en flexion. Remplissant la majorité du cahier des charges, nous avons ensuite mis au point une étude animale, laquelle sera réalisée ultérieurement. Enfin, cette étude a permis de mettre en évidence certaines limitations de l’impression 3D métallique, principalement liés aux surfaces non supportées que nécessitent la reprise de charge. Cette maille très prometteuse est aujourd’hui en cours d’optimisation pour permettre d’être rapidement mise à la disposition des patients. / The work detailed in this thesis is about a titanium 3D printed mesh for large bone defects. Large bone defects are often due to surgical resections, performed after a cancer or an infection. When the defect reach a critical size, bone regeneration is impossible and it often leads to the loss of function. When it happened, the wound need to be cured using reconstructive surgery. The mandibular reconstruction is one of the most performed reconstructive surgery. Nowadays, we reconstruct the mandible with the fibula free flap technique, which require huge amount of time and resources for mixed results (around 10% failure rate). Based on the international literature, we developed a titanium 3D printed mesh to replace the fibula autograft and limit its side effect while offering to mesenchymal cells optimal growing environment. On the mechanical point of view, this environment requires to decrease the titanium initial rigidity from 110GPa to a range between 0.1 and 1GPa. In order to achieve that goal, we have developed a design methodology that lead us to innovation. We developed a load restauration system that allow us to combine low rigidity and high resistance. In order to find the final design, we used finite element modeling. Then, the final design have been tested mechanically in compression, traction and flexion. Because most of the requirements were reached, we designed an animal study which should take place in the next years. Eventually, we discovered some limitation for metallic 3D printing, essentially due to unsupported areas required for the load restauration. This innovative mesh is today optimized in order to be rapidly given to patients in the need.

A compreensão dos fenômenos de reparo ósseo representa parte fundamental da odontologia e da cirurgia bucomaxilofacial. Objetivo: O presente trabalho tem como objetivo avaliar a influência da estimulação de campo magnético sepultado sobre o reparo ósseo em calvária de ratos após reconstrução com enxerto ósseo autógeno, implante de hidroxiapatita granulada sintética ou enxerto alógeno de cartilagem, comparados entre si e aos controles sem estimulação magnética. Materiais e métodos: foram utilizados 95 ratos Wistar machos, divididos em grupos constituidos por 5 animais. Foram realizados defeitos ósseos críticos na calvária dos animais, sendo os mesmos imediatamente reconstruídos, isoladamente com, enxerto ósseo autógeno, hidroxiapatita granulada sintética e enxerto alógeno de cartilagem, sob influência ou não de campos magnéticos sepultados. Foram realizadas avaliações aos 15, 30 e 60 dias pós-operatórios. Apenas um grupo não sofreu intervenção cirúrgica (Naive), para fornecer os dados para obtenção da atividade fisiológica das enzimas fosfatase alcalina e fosfatase ácida. Em todos os tempos experimentais foi realizada a quantificação da neoformação óssea por meio da histomorfometria. A avaliação da intensidade de expressão da proteína osteopontina, foi obtida somente aos 60 dias Resultados: a avaliação histomorfométrica evidenciou interação significativa entre grupos e tempos com p=0,008. Aos 60 dias, nos animais que receberam reconstrução com osso autógeno o grupo sob influência do campo magnético apresentou percentual de preenchimento ósseo superior ao grupo sem influência do estímulo magnético. A mensuração da atividade das enzimas fosfatase alcalina e fosfatase ácida evidenciou interação significativa entre grupos e tempos com p=0,02 e p=0,005 respectivamente. Aos 60 dias, todos os grupos apresentaram atividade de ambas enzimas significativamente inferior ao grupo Naive. A análise imunoistoquímica realizada não evidenciou diferença significativa na expressão da enzima osteopontina com a metodologia empregada. Conclusão: o presente trabalho contribuiu para o entendimento da influência do campo magnético sepultado sobre o reparo ósseo em crânio de rato. A partir dos resultados encontrados, novas metodologias podem ser propostas para complementar os resultados obtidos e fortalecer a presente linha de pesquisa. / Objective: the comprehension of the phenomenon of bone repair represents a fundamental part of dentistry and of oral and maxillofacial surgery. The present work has as its objective, to evaluate the influence of a stimulated magnetic field implanted on the calvarial bone of rats after its reconstruction with autogeneous bone graft, synthetic hydroxyapatite crystals or with the insertion of allogeneic cartilage, in comparison to no magnetic stimulation. Materials e methods: 95 Wistar male rats were used, divided into groups with 5 animals in each. The autogeneous bone graft, the synthetic hydroxyapatite crystals and the insertion of allogeneic cartilage were each used separately in the performed interventions of reconstruction with or without the influence of implanted magnetic fields. Evaluations were performed in 15, 30 and 60 days after surgery. Only one group did not suffer surgical intervention (Naïve); this group provided data for the physiological activity of the alkaline and acid phosphatase enzymes. Also, quantification of bone neoformation was obtained through histomorphometry in all experimental time periods, and evaluation of the osteopontin protein expression of intensity in 60 days. Results: the histomorphometry 60-day evaluation, showed evidence of a significant interaction between the groups and the time of p=0,008 on the animals that received reconstruction with autogeneous bone. The group that was influenced by the magnetic field presented a percent of bone reconstruction superior to that of the group which did not receive magnetic stimulation. In 60 days, activity mensuration of the alkaline and acid phosphatase enzymes, showed evidence of significant interaction between the groups and the times of p=0,02 and p=0,005, respectively. In all groups, activity of both enzymes was present and significantly inferior to the Naive group. The immunohistochemistry analysis performed did not show evidence of any significant difference in the oseopontin enzyme expression with the applied methodology. Conclusion: this work contributed to the understanding of the influence that an implanted magnetic field has on bone reconstruction. From the results found, new methodologies can be proposed as a complementary to obtained results and can strengthen the present line of research.