Fibula free flap reconstruction of the mandible in cancer patients: Evaluation of a combined surgical and prosthodontic treatment concept

The final goal of mandibular reconstruction following ablative surgery for oral cancer is often considered to be dental implant-supported oral rehabilitation, for which bone grafts should ideally be placed in a suitable position taking subsequent prosthetic restoration into account. The aim of this study was to evaluate the efficacy of a standardized treatment strategy for mandibular reconstruction according to the size of the bony defect and planned subsequent dental prosthetic rehabilitation. Data of 56 patients, who had undergone such a systematic mandibular fibula free flap reconstruction, were retrospectively analyzed. Early complications were observed in 41.5% of the patients but only in those who had been irradiated. Late complications were found in 38.2%. Dental implant survival rate was 92%, and dental prosthetic treatment has been completed in all classes of bony defects with an overall success rate of 42.9%. The main reasons for failure of the complete dental reconstruction were patients' poor cooperation (30.4%) and tumour recurrence (14.3%) followed by surgery-related factors (10.8%) such as implant failure and an unfavourable intermaxillary relationship between the maxilla and the mandible. A comparison of our results with the literature findings revealed no marked differences in the complication rates and implant survival rates. However, a systematic concept for the reconstructive treatment like the method presented here, plays an important role in the successful completion of dental reconstruction. The success rate could still be improved by some technical progress in implant and bone graft positioning.

Interventions for the management of mandibular fractures

BACKGROUND Fractures of the mandible (lower jaw) are a common occurrence and usually related to interpersonal violence or road traffic accidents. Mandibular fractures may be treated using open (surgical) and closed (non-surgical) techniques. Fracture sites are immobilized with intermaxillary fixation (IMF) or other external or internal devices (i.e. plates and screws) to allow bone healing. Various techniques have been used, however uncertainty exists with respect to the specific indications for each approach. OBJECTIVES The objective of this review is to provide reliable evidence of the effects of any interventions either open (surgical) or closed (non-surgical) that can be used in the management of mandibular fractures, excluding the condyles, in adult patients. SEARCH METHODS We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 28 February 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 1), MEDLINE via OVID (1950 to 28 February 2013), EMBASE via OVID (1980 to 28 February 2013), metaRegister of Controlled Trials (to 7 April 2013), ClinicalTrials.gov (to 7 April 2013) and the WHO International Clinical Trials Registry Platform (to 7 April 2013). The reference lists of all trials identified were checked for further studies. There were no restrictions regarding language or date of publication. SELECTION CRITERIA Randomised controlled trials evaluating the management of mandibular fractures without condylar involvement. Any studies that compared different treatment approaches were included. DATA COLLECTION AND ANALYSIS At least two review authors independently assessed trial quality and extracted data. Results were to be expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated to include both clinical and methodological factors. MAIN RESULTS Twelve studies, assessed as high (six) and unclear (six) risk of bias, comprising 689 participants (830 fractures), were included. Interventions examined different plate materials and morphology; use of one or two lag screws; microplate versus miniplate; early and delayed mobilization; eyelet wires versus Rapid IMF™ and the management of angle fractures with intraoral access alone or combined with a transbuccal approach. Patient-oriented outcomes were largely ignored and post-operative pain scores were inadequately reported. Unfortunately, only one or two trials with small sample sizes were conducted for each comparison and outcome. Our results and conclusions should therefore be interpreted with caution. We were able to pool the results for two comparisons assessing one outcome. Pooled data from two studies comparing two miniplates versus one miniplate revealed no significant difference in the risk of post-operative infection of surgical site (risk ratio (RR) 1.32, 95% CI 0.41 to 4.22, P = 0.64, I(2) = 0%). Similarly, no difference in post-operative infection between the use of two 3-dimensional (3D) and standard (2D) miniplates was determined (RR 1.26, 95% CI 0.19 to 8.13, P = 0.81, I(2) = 27%). The included studies involved a small number of participants with a low number of events. AUTHORS' CONCLUSIONS This review illustrates that there is currently inadequate evidence to support the effectiveness of a single approach in the management of mandibular fractures without condylar involvement. The lack of high quality evidence may be explained by clinical diversity, variability in assessment tools used and difficulty in grading outcomes with existing measurement tools. Until high level evidence is available, treatment decisions should continue to be based on the clinician's prior experience and the individual circumstances.

Patients with oral tumors. Part 1: Prosthetic rehabilitation following tumor resection. Resection prosthetics: surgery, implants and prosthetic treatment

The present study reports on the surgical and prosthodontic rehabilitation of 46 patients, 31 male and 15 female, after resection of oral tumors. The treatment was carried out from 2004 to 2007 at the Department of Prosthodontics, University of Bern, with a follow-up time of 3 to 6 years. The average age at diagnosis was 54 years. 76% of all tumors were squamous cell carcinoma, followed by adenocarcinoma. Resection of the tumors including soft and/or hard tissues was performed in all patients. 80% of them additionally underwent radiotherapy and 40% chemotherapy. A full block resection of the mandible was perfomed in 23 patients, and in 10 patients, the tumor resection resulted in an oronasal communication. 29 patients underwent grafting procedures, mostly consisting of a free fibula flap transplant. To enhance the prosthetic treatment outcome and improve the prosthesis stability, a total of 114 implants were placed. However, 14 implants were not loaded because they failed during the healing period or the patient could not complete the final treatment with the prostheses. The survival rate of the implants reached 84.2% after 4 to 5 years. Many patients were only partially dentate before the tumors were detected, and further teeth had to be extracted in the course of the tumor therapy. Altogether, 31 jaws became or remained edentulous. Implants provide stability and may facilitate the adaptation to the denture, but their survival rate was compromised. Mostly, patients were fitted with removable prostheses with obturators in the maxilla and implant-supported complete dentures with bars in the mandible. Although sequelae of tumor resection are similar in many patients, the individual intermaxillary relations, facial morphology and functional capacity vary significantly. Thus, individual management is required for prosthetic rehabilitation.

Influence of contact points on the performance of caries detection methods in approximal surfaces of primary molars: an in vivo study

This in vivo study aimed to evaluate the influence of contact points on the approximal caries detection in primary molars, by comparing the performance of the DIAGNOdent pen and visual-tactile examination after tooth separation to bitewing radiography (BW). A total of 112 children were examined and 33 children were selected. In three periods (a, b, and c), 209 approximal surfaces were examined: (a) examiner 1 performed visual-tactile examination using the Nyvad criteria (EX1); examiner 2 used DIAGNOdent pen (LF1) and took BW; (b) 1 week later, after tooth separation, examiner 1 performed the second visual-tactile examination (EX2) and examiner 2 used DIAGNOdent again (LF2); (c) after tooth exfoliation, surfaces were directly examined using DIAGNOdent (LF3). Teeth were examined by computed microtomography as a reference standard. Analyses were based on diagnostic thresholds: D1: D 0 = health, D 1 –D 4 = disease; D2: D 0 , D 1 = health, D 2 –D 4 = disease; D3: D 0 –D 2 = health, D 3 , D 4 = disease. At D1, the highest sensitivity/specificity were observed for EX1 (1.00)/LF3 (0.68), respectively. At D2, the highest sensitivity/ specificity were observed for LF3 (0.69)/BW (1.00), respectively. At D3, the highest sensitivity/specificity were observed for LF3 (0.78)/EX1, EX2 and BW (1.00). EX1 showed higher accuracy values than LF1, and EX2 showed similar values to LF2. We concluded that the visual-tactile examination showed better results in detecting sound surfaces and approximal caries lesions without tooth separation. However, the effectiveness of approximal caries lesion detection of both methods was increased by the absence of contact points. Therefore, regardless of the method of detection, orthodontic separating elastics should be used as a complementary tool for the diagnosis of approximal noncavitated lesions in primary molars.

Geochemistry and mineralogy of selected carbonaceous claystones at DSDP Hole 76-534

Four dominant depositions of carbonaceous claystones are recognized to have occurred during the early Aptian to middle Albian at Site 534. There are correlations of stable isotope ratios with organic carbon content and of clay content with clay mineralogy of the samples. Almost all organic carbon in these sequences has very negative terrestrial isotope ratios, and the clay of that age indicates predominance of aluminous montmorillonite, which is thought to be of terrigenous origin. It is suggested that development of coastal vegetation belts and deltaic outbuilding with consequent outpouring of land-plant detritus and terrigenous elastics into the deep basins probably led to formation of the "black shale" facies.

Sedimentology and origin of lower Cretaceous pelagic carbonates and redeposited clastics at DSDP Hole 76-534A

Drilling at Site 534 in the Blake-Bahama Basin recovered 268 m of Lower Cretaceous, Berriasian to Hauterivian, pelagic carbonates, together with volumetrically minor intercalations of claystone, black shales, and terrigenous and calcareous elastics. Radiolarian nannofossil pelagic carbonates accumulated in water depths of about 3300 to 3650 m, below the ACD (aragonite compensation depth) but close to the CCD (calcite compensation depth). Radiolarian abundance points to a relatively fertile ocean. In the Hauterivian and Barremian, during times of warm, humid climate and rising sea level, turbiditic influxes of both terrigenous and calcareous sediments, and minor debris flows were derived from the adjacent Blake Plateau. The claystones and black shales accumulated on the continental rise, then were redeposited onto the abyssal plain by turbidity currents. Dark organic-rich and pale organic-poor couplets are attributed to climatic variations on land, which controlled the input of terrigenous organic matter. Highly persistent, fine, parallel lamination in the pelagic chalks is explained by repeated algal "blooms." During early diagenesis, organic-poor carbonates remained oxygenated and were cemented early, whereas organic-rich intervals, devoid of burrowing organisms, continued to compact later in diagenesis. Interstitial dissolved-oxygen levels fluctuated repeatedly, but bottom waters were never static nor anoxic. The central western Atlantic in the Lower Cretaceous was thus a relatively fertile and wellmixed ocean basin.

Lithology and organic geochemistry at DSDP Hole 76-534

The organic facies of Early and middle Cretaceous sediments drilled at DSDP Site 534 is dominated by terrestrially derived plant remains and charcoal. Marine organic matter is mixed with the terrestrial components, but through much of this period was diluted by the terrestrial material. The supply of terrestrial organic matter was high here because of the nearness of the shore and high runoff promoted by a humid temperate coastal climate. Reducing conditions favored preservation of both marine and terrestrial organic matter, the terrestrial materials having reached the site mostly in turbidity currents or in the slow-moving, near-bottom nepheloid layer. An increase in the abundance of terrestrial organic matter occurred when the sea level dropped in the Valanginian and again in the Aptian-Albian, because rivers dumped more terrigenous elastics into the Basin and marine productivity was lower at these times than when sea level was high. A model is proposed to explain the predominance of reducing conditions in the Valanginian-Aptian, of oxidizing conditions in the late Aptian, and of reducing conditions in the Albian-Cenomanian. The model involves influx of oxygen-poor subsurface waters from the Pacific at times of high or rising sea level (Valanginian-Aptian, and Albian- Cenomanian) and restriction of that influx at times of low sea level (late Aptian). In the absence of a supply of oxygenpoor deep water, the bottom waters of the North Atlantic became oxidizing in the late Aptian, probably in response to development of a Mediterranean type of circulation. The influx of nutrients from the Pacific led to an increase in productivity through time, accounting for an increase in the proportion of marine organic matter from the Valanginian into the Aptian and from the Albian to the Cenomanian. Conditions were dominantly oxidizing through the Middle Jurassic into the Berriasian, with temporary exceptions when bottom waters became reducing, as in the Callovian. Mostly terrestrial and some marine organic matter accumulated during the Callovian reducing episode. When Jurassic bottom waters were oxidizing, only terrestrial organic matter was buried in the sediments, in very small amounts.

Geochemistry of evaporite in the Red Sea

One of the major shipboard findings during Leg 23 drilling in the Red Sea was the presence of late Miocene evaporites at Sites 225, 227, and 228. The top of the evaporite sequence correlates with a strong reflector (Reflector S) which has been mapped over much of the Red Sea (Ross et al., 1969, Phillips and Ross, 1970). This indicates that the Red Sea appears to be extent. Miocene sediments, including evaporites, are known from a few outcrops along the coastal plains of the Gulf of Suez to lat 14°N (Sadek, 1959, cited in Friedman, 1972; Heybroek, 1965; Friedman, 1972). Along the length of the Red Sea, the presence of Miocene salt is indicated by seismic reflection studies (Lowell and Genik, 1972) and confirmed by drilling. The recently published data from deep exploratory wells (Ahmed, 1972) demonstrate the great thickness of elastics and evaporites which were deposited in the Red Sea depression during Miocene time. The Red Sea evaporites are of the same age as the evaporites found by deep sea drilling (DSDP Leg 13) in the Mediterranean Sea. Therefore, Reflector S in the Red Sea is comparable to Reflector M in the Mediterranean. It is assumed that during Miocene time a connection between these two basins was established (Coleman, this volume) resulting in a similar origin for the evaporites deposited in the Red Sea and in the Mediterranean Sea. The origin of the Mediterranean evaporites has been discussed in great detail (Hsü et al., 1973; Nesteroff, 1973; Friedman, 1973). The formation of evaporites may be interpreted by three different hypotheses. 1) Evaporation of a shallow restricted shelf sea or lagoon which receives inflows from the open ocean. 2) Evaporation of a deep-water basin which is separated from the open ocean by a shallow sill (Schmalz, 1969). 3) Evaporation of playas or salt lakes which are situated in desiccated deep basins isolated from the open ocean (Hsü et al., 1973). The purpose of this study is to show whether one of these models might apply to the formation and deposition of the Red Sea evaporites. Therefore, a detailed petrographic and geochemical investigation was carried out.

Geochemistry and isotopes at DSDP Hole 79-546

At Site 546, below the Mazagan Escarpment at a water depth of 4 km, 36 m of salt rock was cored from the top of one of a field of salt domes. The core was studied by thin section and a variety of geochemical procedures. The salt rock contains 0.1 to 3% carnallite and lesser amounts of sylvite and polyhalite, which with the corresponding high level of bromide place it within the potash evaporite facies. The bromide profile is of a dominantly marine evaporite deposited in moderately shallow brine which, however, was not repeatedly desiccated. A mineralogical argument suggests that the brine surface was not below sea level. An average of about 5% elastics, with dispersed anhydrite, darken the salt rock to deep shades of red, brown, and gray green. Most of the included materials are in highly deformed boudins or dispersions in the salt rock that has also undergone cataclasis in a subsequent, probably tectonic, deformation. The salt rock is slightly deficient in anhydrite, and the usual separate beds and laminae of anhydrite are virtually absent. Stable isotope ratios of sulfur and oxygen in the sulfate are clearly derived from sea water of Permian to Scythian age, in contrast to the late Triassic or Early Jurassic age of evaporites onshore in Morocco and Portugal and the corresponding evaporites offshore Maritime Canada. In contrast to those evaporites off the axis of Atlantic rifting, the salt at Site 546 may have been deposited in a very early central rift fed by marine waters from Tethys through the Gibraltar or South Atlas fracture zones.

Percepção dos Ortodontistas quanto à época ideal para o tratamento ortodôntico da má oclusão de Classe II de Angle.

O objetivo deste estudo foi verificar, por meio de questionário, a percepção dos ortodontistas quanto a época ideal para o tratamento ortodôntico da má oclusão de Classe II de Angle, avaliar a eficiência deste tipo de tratamento em uma ou duas fases e identificar os diversos métodos de tratamento utilizados. A amostra constituiu de 163 ortodontistas brasileiros que responderam ao questionário via e-mail. O questionário continha perguntas do tipo aberta, semi aberta e fechada, e, para sua validação, foi realizado um teste piloto entre 15 ortodontistas, participantes ou ex-alunos do Programa de Pós-graduação em Odontologia da Universidade Metodista de São Paulo, que não foram inclusos neste trabalho. Os dados foram tabulados com a utilização de frequência absoluta (n) e frequência relativa (%). Para verificar a correlação entre as variáveis ordinais foi utilizado o Coeficiente de Correlação de Spearman. Para verificar a associação entre variáveis qualitativas nominais foi utilizado o teste do qui-quadrado. Em todos os testes foi adotado nível de significância de 5% (p<0,05). Todos os procedimentos estatísticos foram executados no programa Statistica v.5.1 (StatSoft Inc., Tulsa, USA). Observou-se que os ortodontistas brasileiros preferem tratar os pacientes portadores da má oclusão de Classe II durante a fase da dentadura mista tardia, onde a procura por tratamentos nos consultórios e/ou clínicas tem maior ocorrência entre 10 a 13 anos e no sexo feminino. Dentre as modalidades de tratamento, verificou-se que 25 a 50% dos profissionais tratam seus pacientes em duas fases, seja na utilização do Aparelho Extra Bucal (49,1%), Bionator (33,1%) ou propulsores mandibulares, como APM (17,8%), e, Elásticos Classe II (8,6%).

Comparación entre los efectos de un programa de entrenamiento de fuerza explosiva mediante bandas elásticas y un programa de entrenamiento con electro-estimulación de cuerpo completo

El objetivo del presente estudio fue analizar los cambios en el rendimiento en función de dos métodos de entrenamiento, el desarrollado mediante electro-estimulación muscular integral (EMI) frente a otro en el que se utilizaron bandas elásticas y que denominamos entrenamiento funcional con elásticos (EFE). La muestra estuvo compuesta por un grupo de diez (N=10) personas físicamente activas (23,04 ± 2,5 años). Se utilizó un diseño cuasi-experimental con medidas pre-post. Y fueron analizados los resultados de las pruebas: salto vertical con ayuda de brazos; y velocidad de desplazamiento en una carrera de ida y vuelta de 12 metros de distancia (6+6). Se realizó un análisis descriptivo de casos y medias. Y dado el tamaño de la muestra se calculó el tamaño del efecto, el cual fue bajo o moderado (d<0,5). Por último se compararon las diferencias de las medias de los grupos mediante la U de Mann Whitney, y las diferencias de las medias en función del tiempo (pre-post) mediante Friedman; en ambos casos los resultados no fueron significativos (p<0,5). En cuanto a los valores descriptivos del pre-post en ambos grupos: el grupo que entrenó con bandas elásticas obtuvo mejores resultados en ambas pruebas que el grupo que entrenó con EMI. En conclusión, el entrenamiento con bandas elásticas, a pesar de no ser significativo, parece mostrarse más efectivo que el entrenamiento con electro-estimulación muscular integral. Si bien, dadas las limitaciones del estudio estos datos hay que tomarlos con la pertinente cautela.