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Journal of Instrumentation 15(05), P05006 (2020). doi:10.1088/1748-0221/15/05/P05006, This article explores the viability of nitrogen enriched silicon for particle physics application. For that purpose silicon diodes and strip sensors were produced using high resistivity float zone silicon, diffusion oxygenated float zone silicon, nitrogen enriched float zone silicon and magnetic Czochralski silicon. The article features comparative studies using secondary ion mass spectrometry, electrical characterization, edge transient current technique, source and thermally stimulated current spectroscopy measurements on sensors that were irradiated up to a fluence of 10$^{15}$ n$_{eq}$/cm$^2$. Irradiations were performed with 23 MeV protons at the facilities in Karlsruhe (KIT), with 24 GeV/c protons at CERN (PS-IRRAD) and neutrons at the research reactor in Ljubljana. Secondary ion mass spectrometry measurements give evidence for nitrogen loss after processing, which makes gaining from nitrogen enrichment difficult., Published by Inst. of Physics, London

In order to cope with the occupancy and radiation doses expected at the High-Luminosity LHC, the ATLAS experiment will replace its Inner Detector with an all-silicon Inner Tracker (ITk), consisting of pixel and strip subsystems. In the last two years, several prototype ITk strip modules have been tested using beams of high energy electrons produced at the DESY-II testbeam facility. Tracking was provided by EUDET telescopes. The modules tested are built from two sensor types: the rectangular ATLAS17LS, which will be used in the outer layers of the central barrel region of the detector, and the annular ATLAS12EC, which will be used in the innermost ring (R0) of the forward region. Additionally, a structure with two R0 modules positioned back-to-back has been measured, demonstrating space point reconstruction using the stereo angle of the strips. Finally, one barrel and one R0 module have been measured after irradiation to 40% beyond the expected end-of-lifetime fluence. The data obtained allow for thorough tests of the module performance, including charge collection, noise occupancy, detection efficiency, and tracking performance. The results give confidence that the ITk strip detector will meet the requirements of the ATLAS experiment.

There is a lack of consistency among published reports in the definition of what constitutes close resection margins (1-5mm) in the surgical treatment of oral and oropharyngeal squamous cell carcinoma (SCC). Our aim was to define what would constitute close resection margins in predicting local recurrence and disease-specific survival. The study comprised 192 previously untreated patients with oral and oropharyngeal SCC who were recruited at the Southern General Hospital, Glasgow, from 2001 to 2007 with a minimum follow-up of 2 years. Resection was the primary treatment and the surgical margins were recorded for all patients. Statistical analyses were aided by the Statistical Package for the Social Sciences, version 15.0, and MedCalc software. The status of the surgical margins was evaluated using a receiver operating characteristic (ROC) curve to define the cut-off point. Cox's proportional hazard model was used to establish predictive factors for local recurrence and disease-specific survival. Of 192 patients, 23 (12%) had involved margins (1.0mm), 107 (56%) had close margins (1.0-2.0mm (16.1%); 2.1-3.0mm (12%); 3.1-4.0mm (10.4%); 4.1-5.0mm (17.2%), and 62 (32.3%) had clear margins (5mm). No predictive cut-off point was found that related close surgical margins to local recurrence. However, there was a significant adverse association between surgical margins ≤1.6mm and disease-specific survival. In recommending postoperative adjuvant treatment for oral and oropharyngeal SCC, we suggest that surgical margins within 2mm should be considered as the cut-off. However, other clinical and pathological prognostic factors should also be taken into consideration when recommending further treatment.

A systematic study was carried out using plastic model skulls to quantify the accuracy of the transfer of face bow registration to the articulator. A standard Dentatus semi-adjustable articulator system was compared to a purpose built orthognathic articulator system by measuring the maxillary occlusal plane angles of plastic model skulls and of dental casts mounted on the two different types of articulators. There was a statistically significant difference between the two systems; the orthognathic system showed small random errors, but the standard system showed systematic errors of up to 28°.

The errors produced by occlusal wafers constructed on casts of the teeth mounted on a standard articulator and an improved orthognathic articulator were investigated by carrying out simulated orthognathic surgery on plastic skulls. The wafers were used to relocate the position of the maxillae of the skulls. The vertical and horizontal displacements of the maxillae were determined from measurements of the positions of markers on the skull and teeth. Comparison of the magnitudes of the actual and intended movements showed that wafers constructed on the standard articulator had systematic prediction errors of up to 5 mm, but the improved orthognathic articulator showed much smaller random errors. There was a statistically significant improvement in overall accuracy in predicting maxillary Le Fort I position with the use of the improved orthognathic articulator which the authors recommend for clinical use.

We present a new method for replicating the skull and occlusal surface with an accurate physical model that could be used for planning orthognathic surgery. The investigation was made on 6 human skulls, and a polyvinyl splint was fabricated on the dental cast of the maxillary dentition in each case. A cone beam computed tomogram (CBCT) was taken of each skull and a three-dimensional replica produced. The distorted dentition (as a result of magnification errors and streak artefacts) was removed from the three-dimensional model and replaced by new plaster dentition that was fabricated using the polyvinyl splint and a transfer jig replication technique. To verify the accuracy of the method the human skulls and the three dimensional replica model, with the new plaster dentition in situ, were scanned using a laser scanner. The three-dimensional images produced were superimposed to identify the errors associated with the replacement of the distorted occlusal surface with the new plaster dentition. The overall mean error was 0.72 and SD was (0.26) mm. The accuracy of the method encouraged us to use it clinically in a case of pronounced facial asymmetry.

History and admission findings In the 20-year-old patient increasing arthralgia since the age of seven years had caused functional impairment. As seronegative osteodestructive rheumatoid arthritis had been suspected, he was treated with methotrexate and steorid for ovemore than one year, without success.r Investigations The clinical examination revealed a compromised function of the knee and hip joints. Conventional radiographs showed severe degenerative changes in these regions. The radiographs of the lumbar and the thoracic spine were suggestive of osteoporotic fractures. Diagnosis, treatment and course The clinical and radiological findings led to the suspicion of a hereditary collagenous disease. Genetic analyses revealed a COL2A1 mutation. The treatment included analgesics, non-steroidal antirheumatic drugs, opiates and regular physiotherapy to build up and maintain muscle strength. Conclusion In young adult patients with osteoarthritis mutations in the COL2A1 gene should considered. This mutation with the substitution pArg75Cys should be in focus because of the phenotypes in clinical manifestations.

The results of orthognathic surgery may differ significantly from the planned outcome using dental models. The orientation of dental models mounted on articulators using conventional face bows does not accurately replicate the orientation of the patients' teeth and jaws, but introduces a systematic error. A mathematical analysis showed that the misalignment of the maxillary model introduces errors in the perioperative wafers, which may lead to the incorrect surgical positioning of the maxilla reported in the literature. The results of the mathematical analysis were validated by image analysis of photographs of mounted maxillary models, used to simulate five orthognathic procedures. No significant difference between the experimental results and the theoretical predictions from the mathematical equations was noted. Planning for maxillary forward and upward movement produced more advancement and only 50% of maxillary impaction. Planning for maxillary forward and downward movement produced less advancement and more inferior displacement in relation to horizontal and vertical reference planes.

The purpose of this study was to evaluate the accuracy of model surgery prediction after orthognathic surgery and to identify possible errors associated with the prediction process. The study included 46 patients who had undergone orthognathic surgical procedures; 22 in Group A who had had a Le Fort I osteotomy; and 24 in Group B who had had a Le Fort I osteotomy and mandibular setback surgery. The immediate postoperative and preoperative lateral cephalograms were analysed to calculate surgical changes; these were compared with those obtained from model surgery prediction and a statistical analysis was undertaken. The maxilla was more under-advanced and over-impacted anteriorly than predicted by model surgery. The amount of mandibular setback was more than that predicted by model surgery. None of the differences between prediction planning and actual surgical changes was statistically significant at p

Patients who require orthognathic surgery may have asymmetry of the position of the temporomandibular joints relative to the maxilla, which is impossible to reproduce on the current semiadjustable articulators used for surgical planning. We describe a highly-adjustable spirit level orthognathic face bow that allows records to be made of patients with asymmetrical maxillae. The orthognathic articulator also allows the position of the condylar components of the articulator to be adjusted in three dimensions. The use of the new face bow and articulator made it possible to mount the dental casts of asymmetrical faces to reproduce their clinical appearance. The devices were evaluated by comparing the measurements of anatomical variables obtained from cephalometric radiographs with equivalent values obtained from the orthognathic articulator and casts mounted on the articulator. Although the measurements showed significant intersubject variability, the angle between the horizontal and maxillary occlusal plane, occlusal cant angle, and intercondylar widths, were not significantly different.

Orthognathic surgery that involves movement of the maxilla relative to the skull is usually planned using casts mounted on an articulator. Accurate positioning of the maxilla relative to the skull is essential for reliable planning, but current methods of mounting casts on articulators are inaccurate and unreliable. We propose that the casts should be mounted using the relation between the horizontal plane and the resting head position to define the position of the skull. A photographic study of 10 subjects confirmed the reproducibility of the head position and its relation to the horizontal plane. A face bow incorporating a circular spirit level was used to transfer the relation between the horizontal and the maxillary dentition to a semiadjustable articulator. The angle between the horizontal and maxillary occlusal planes was measured from six lateral cephalograms and compared with those of casts mounted on a semiadjustable articulator using a face bow with either an orbital pointer or a spirit level. The face bow with a spirit level produced considerably more accurate results.

The aim of this study was to investigate the feasibility of reconstructing critical size continuity osteoperiosteal defects of the mandible using a composite of recombinant BMP-7 contained in a bovine type-1 collagen carrier wrapped in a pedicled sterno-occipitalis muscle flap. At 3 months following surgery, bridging of the surgical defect was noted in three subjects (60%). Histologically, the induced bone regenerate showed maturation from woven to lamellar bone. Islands of cartilage were distributed throughout the defect. Replacement ossification of the degenerated muscle was a common feature in all specimens. Microradiography showed a gradual increase in the calcification of mineralized tissue from the margin to the centre of the newly generated bone. This research represents a proof of the concept that bone can be satisfactorily formed within a muscular scaffolding at the site of the created defect in a one-stage procedure.

This investigation aimed to compare and contrast practical difficulties experienced by 54 children from three different centres (Mexico City, New York, Paris) treated with either extra-oral or intra-oral distraction devices. The possible effect of distraction osteogenesis on pain/sleeping difficulty, speech and eating problems and disturbance of recreational activities and alteration in sensation were investigated. It was expected that intra-oral devices would reduce the difficulties associated with the distraction process and their psychological effect on the child. Some benefits resulting from the use of intra-oral devices were identified, these included fewer sleeping problems (P = 0.006) and less disturbance of recreational activities (P = 0.002). However, eating and maintaining oral hygiene were more problematic with intra-oral devices the differences between the intra-oral and extra-oral groups was approaching significance at P = 0.07. A major disadvantage of the extra oral device was scarring. In both groups the alteration of lip sensation was temporary, pain was limited to the time of activation of the distraction device. A high level of patients' cooperation was mandatory for successful completion of the treatment.

Fourteen patients or their immediate family were interviewed about their experiences of having either unilateral or bilateral external distraction osteogenesis of the mandible. The patients showed a high level of co-operation with treatment. Six of the 14 patients required repeat distractions, and had been informed and accepted that this was a possibility before the initial distraction. However, patients or their parents expressed some reservations about the extraoral distractors, which prevented them from practising their favourite sport and made them vulnerable to bullying by their friends and colleagues. Patients had moderate pain when the appliances were removed. They all expressed their satisfaction with the results and would recommend this treatment to others. Problems, including speech, eating, pain, and sleeping difficulties, were encountered by patients at all stages of treatment. Of considerable concern was the disruption of education when the child was treated during the school term.

Infection of soft tissues surrounding extra-oral craniofacial endosseous implants is a common clinical problem. The aim of this study was to analyse the microflora associated with such implants, in both health and disease. Eighteen patients with a total of 49 implants were studied. Each patient was seen on two occasions for both a clinical examination and for collection of microbiological samples, using swabs and paper points, from the peri-abutment soft tissues. Specimens were cultured on blood agar and on agars selective for staphylococci and yeasts. Isolates were identified and selective antibiotic susceptibility testing undertaken. No single organism emerged as a predominant cause of peri-abutment skin infection but Staphylococcus aureus, Gram-negative bacilli and yeasts were all present as potential pathogens in this context. Culture and sensitivity results should therefore guide the treatment of these infections.

Objectives: Correction of craniofacial microsomia (CFM) presents several challenges concerning the modality of surgical intervention. The aim of this study was to assess early and late surgical outcome, by undertaking Euclidean distance matrix analysis (EDMA) of CFM patients exhibiting an unilateral mandibular deformity that was surgically corrected by an inverted L osteotomy and autogenous bone graft. Design: Longitudinal study. Preoperative, ≈1-year postoperative and ≈3-year postoperative assessments of 14 consecutive children (mean age 9 years) with CFM. Posteroanterior cephalographs were scanned and five homologous mandibular landmarks were digitized in triplicate (< 1% digitization error). Average mandibular geometries, scaled to an equivalent size, were generated using a generalized rotational fit program (Procrustes superimposition) and subjected to EDMA. Results: The mean pre- and both postoperative mandibular configurations differed statistically (p < .01). Early postoperative improvemen...

We compared the use of one miniplate (n = 36) with that of two miniplates (n = 26) for the treatment of the mandibular angle in a randomised trial. There were no significant differences between the groups in total morbidity (22/36 compared with 14/26) or for individual complications. We conclude that two miniplates seem to confer no extra benefit to patients, but a much larger trial would be required to show this conclusively.

We describe a vision-based three-dimensional facial data capture system designed for the planning of maxillofacial operations. We describe the system requirements and outline the methods used to develop a complete three-dimensional facial capture system. Our approach is based upon imaging the face using two stereo-pair sets of cameras. Scale-space-based stereo-matching is then used to recover correspondences between each of the captured stereo-pairs. Photogrammetric routines based on adjustment of bundles are used off-line to calibrate the system by imaging a single object that references all cameras to the same co-ordinate frame. This calibration scheme allows us to convert stereo correspondences to world points for each pair of cameras without the need for any subsequent fusion of data. Initial results show that we are able to capture key facial landmarks to within 0.5 mm.

Sensory disturbance following orbitozygomatic complex fractures was studied in 65 patients from 4 treatment groups which represented potentially varying degrees of sensory disturbance. The fracture-type-dependent treatments were: no surgical intervention ( n =20), closed reduction with or without wire fixation ( n =17), open reduction with miniplate fixation ( n =15) and/or reconstruction of the orbital floor ( n =13). In order to assess the sensory function of different classes of afferent fibres, several methods of sensory testing were applied. On average 6.3 months after treatment, the patient's report was obtained, and tests regarding touch, two methods of two-point discrimination, and cold were applied on the cheek and upper lip. The degree of sensory disturbance was method-dependent. In patients who underwent closed reduction, pronounced levels of positive correlation occurred between results from different tests or from both test sites. The levels of these correlations were, in general, low for all other treatments. These findings suggest that afferent fibres of both large and small diameter tended to be permanently damaged in the patient group with closed reduction. In contrast, the types of sensory afferent fibres that were involved in the trauma and/or their recovery were highly variable within patients and sites for all other treatment groups.

Sensory disturbance following orbitozygomatic complex fractures was studied in 65 patients in relation to type of fracture and method of treatment. The fracture-type-dependent treatments were: no surgical intervention (n=20), closed reduction with or without wire fixation (n=17), open reduction with miniplate fixation (n=15) and/or reconstruction of the orbital floor (n=13). Several methods were applied to assess sensory function, on average 6.3 months after treatment, i.e. the patient's report and tests regarding touch, two methods of two-point discrimination, and cold, all applied on the cheek and upper lip. The various examinations indicated that, on average, the long-term sensory disturbance was most pronounced and severe in patients who underwent closed reduction without miniplate fixation. As the sensory disturbance of patients with open reduction and miniplate fixation approached the base-line level of patients for whom surgical intervention was not indicated, open reduction with miniplate fixation can be recommended as treatment for frontozygomatic suture fractures. The degree of sensory disturbance of patients who underwent orbital floor reconstruction was intermediate compared to patients with closed and open reduction respectively.

1. GABAergic innervation of oxytocin neurones is particularly abundant during lactation, but little is known about its functional role. In this study, the role of GABAA receptors in the suckling-induced bursting activity of oxytocin neurones was investigated in lactating rats. GABAA agonists or antagonists were applied by pressure injection into the immediate neighbourhood of recorded neurones while simultaneous recordings were made from oxytocin neurones in the contralateral supraoptic nucleus. 2. GABA and the GABA agonist isoguvacine decreased the basal electrical activity while application of GABAA antagonists (picrotoxin and gabazine) increased the basal electrical activity. However, in marked and unexpected contrast, application of GABA and isoguvacine facilitated or triggered milk-ejection reflex bursting activity whereas GABAA antagonists interrupted this reflex activity. 3. Systemic injection of hypertonic saline is known to increase the firing rate of neurones in the supraoptic nucleus and temporarily to interrupt suckling-induced bursting activity. Application of GABA into one supraoptic nucleus counteracted this inhibitory effect on milk ejection. 4. These observations can be explained if the role of the important GABAergic innervation of oxytocin neurones during lactation is to favour the expression of the stereotyped suckling-induced bursting activity. It might do this by attenuating inputs unrelated to suckling which are incompatible with bursts.

Purpose: A retrospective review of silicone rubber (Silastic; Dow Corning, Midland, MI) implants placed in orbits was undertaken. These implants were used to reconstruct defects in the orbital floor and/or walls secondary to trauma, or those created during malar or orbital osteotomies. The purpose of the study was to determine the incidence of removal of these implants from the surgical site. Materials and Methods: The records of 311 patients treated over a 20-year period were reviewed. Of these, 302 had received silastic implants secondary to trauma. Results: Forty-one patients (13%) had their implant removed at a second operation. The reasons for removal included infection, migration of the implant, worsening eye signs such as diplopia, and others. Conclusion: Because there was a clinically significant rate of removal of this material, consideration should be given to the use of other available materials.

61 orthognathic surgery patients were studied (39% male, 61% female). It confirms that the group of patients we see in the West of Scotland are well adjusted psychologically and that the majority seek orthognathic surgery for aesthetic reasons. The degree of satisfaction is high (87%). Dissatisfaction is not related to sex, age or procedure. Patients who were dissatisfied tend to have higher neuroticism scores on the Eysenck Personality Inventory and those patients who had had unreal expectations of post surgical pain, numbness and swelling, were likely to express dissatisfaction with the outcome in the early stages. Several patients initially expressed some dissatisfaction with the outcome after 3 months then went on to increase their score and by 12 months became satisfied with the procedure. The authors outline the importance of adequate patient preparation prior to surgery and the use of printed literature is recommended.

Central oxytocin administration has a profound facilitatory effect on the patterning of the milk-ejection reflex in the lactating rat. Lesion and microinjection studies indicate that this action is, in part, mediated via a population of limbic neurones in the bed nuclei of the stria terminalis and ventrolateral septum, which have been shown to possess oxytocin receptors and to be activated by selective oxytocin-receptor agonists in vitro. In vivo electro-physiological recordings reveal that some of these neurones display cyclical activity which is highly correlated to each milk ejection, and are rapidly activated following i.c.v. administration of oxytocin. coincident with the facilitation of milk ejection activity. A hypothetical model is proposed in which this population of limbic neurones serves to gate the activity of a pacemaker which, in turn, coordinates the bursting of hypothalamic magnocellular neurones. The oxytocin innervation of these neurones and their expression of oxytocin receptors increases in the post-partum period, and the resultant enhanced sensitivity leads to a greater facilitatory response during lactation. Inhibitory opioid and noradrenergic inputs which converge on these oxytocin-sensitive neurones may function to switch off the facilitatory circuit during periods of stress. Thus, this population of limbic neurones participates in the regulation of neuroendocrine activity during lactation by providing an appropriate degree of feedback to alter the patterning of the milk-ejection reflex.

During cone beam computed tomography (CBCT) scanning, intra-oral metallic objects may produce streak artefacts, which impair the occlusal surface of the teeth. This study aimed to determine the accuracy of replacement of the CBCT dentition with a more accurate dentition and to determine the clinical feasibility of the method. Impressions of the teeth of six cadaveric skulls with unrestored dentitions were taken and acrylic base plates constructed incorporating radiopaque registration markers. Each appliance was fitted to the skull and a CBCT performed. Impressions were taken of the dentition with the devices in situ and dental models were produced. These were CBCT-scanned and the images of the skulls and models imported into computer-aided design/computer-aided manufacturing (CAD/CAM) software and aligned on the registration markers. The occlusal surfaces of each dentition were then replaced with the occlusal image of the corresponding model. The absolute mean distance between the registration markers in the skulls and the dental models was 0.09 ± 0.02 mm, and for the dentition was 0.24 ± 0.09 mm. When the method was applied to patients, the distance between markers was 0.12 ± 0.04 mm for the maxilla and 0.16 ± 0.02 mm for the mandible. It is possible to replace the inaccurate dentition on a CBCT scan using this method and to create a composite skull which is clinically acceptable.

In the preceding article, a dorsochiasmatic area (DCh) was described that projects to both paraventricular (PVN) and supraoptic (SON) nuclei. The main afferents of the DCh, revealed by local injections of retrograde tracers, are the hypothalamic PVN and SON, lateral septal nuclei (LSV and SHy), bed nuclei of the stria terminalis (BST), anteroventral third ventricle region, particularly the median preoptic nucleus (MnPO), the subfornical organ, medial preoptic areas, arcuate hypothalamic nucleus, ventromedial hypothalamic nuclei, paraventricular thalamic nucleus, and, more caudally, several structures of the posterior hypothalamus and mesencephalon. The relations between DCh and BST, LSV, SHy, or MnPO appeared reciprocal. In view of their reciprocal relationships with the hypothalamo-neurohypophyseal system and some of their related extrahypothalamic structures, the DCh might be involved in the regulation of the vasopressin (AVP) and/or oxytocin (OT) systems, or in reproductive behavior.

In the 20-year-old patient increasing arthralgia since the age of seven years had caused functional impairment. As seronegative osteodestructive rheumatoid arthritis had been suspected, he was treated with methotrexate and steorid for ovemore than one year, without success.rThe clinical examination revealed a compromised function of the knee and hip joints. Conventional radiographs showed severe degenerative changes in these regions. The radiographs of the lumbar and the thoracic spine were suggestive of osteoporotic fractures.The clinical and radiological findings led to the suspicion of a hereditary collagenous disease. Genetic analyses revealed a COL2A1 mutation. The treatment included analgesics, non-steroidal antirheumatic drugs, opiates and regular physiotherapy to build up and maintain muscle strength.In young adult patients with osteoarthritis mutations in the COL2A1 gene should considered. This mutation with the substitution pArg75Cys should be in focus because of the phenotypes in clinical manifestations.

Article de synthese sur les effets centraux de l'ocytocine chez les mammiferes: effets physiologiques et comportementaux; site cerebral et mecanisme d'action de l'ocytocine; sites de liaisons de l'ocytocine dans le cerveau et relation avec son activite biologique

We have used a two-part interlocking titanium plate for cranioplasty in two patients with large skull defects in which reconstruction with a titanium plate was required and extensive contouring of the plate was necessary.

Purpose To investigate whether there were any significant differences in the mode of presentation, treatment, and outcome of patients presenting with a primary diagnosis of ameloblastoma in Glasgow, Scotland and San Francisco, CA. Materials and Methods All cases of ameloblastoma seen in both institutions between January 1, 1980 and December 31, 1999 were included in this study. Mode of presentation, radiographic appearance, histologic appearance, treatment, and follow-up were recorded. Results There were no significant differences in the clinical features on presentation (swelling, followed by pain, and altered sensation), the radiographic appearance (unilocular approximately 30% and multilocular 70%), or management with either local treatment (enucleation and/or curettage in just over 50% of cases) or radical treatment (a form of resection in under 50%) in the 50 cases included in this study. Primary care by conservative treatment led to a recurrence in approximately 80% of cases and this included cases of unicystic ameloblastoma. Conclusion The mode of presentation, diagnosis, and management of the ameloblastoma was remarkably similar in Glasgow and San Francisco. The recurrence rate following local enucleation and curettage was unacceptably high, and this included the cases of unicystic ameloblastoma, which should be treated more aggressively than has been recommended in the past.

This study compared the morbidity associated with transconjunctival and transcutaneous approaches for orbital floor exploration with respect to the position of the lower eyelid following surgery. Two groups of 32 volunteers and 32 patients (12 transconjunctival and 20 transcutaneous) were recruited and three-dimensional (3D) imaging was carried out at 6 months following surgery. In the transcutaneous group, there were significant variations in the shape of the lower eyelid, with more medial displacement of the exocanthion. No significant differences were detected in the transconjunctival group compared to controls. The use of a 3D imaging system provided an objective method of assessing this aspect of morbidity associated with the use of lower eyelid incisions.

The aim of the study was to compare the incidence of sella turcica bridging and sella turcica dimensions in 150 Caucasian subjects who had combined surgical-orthodontic correction of their malocclusion with a randomly selected group of 150 Caucasian subjects who were treated contemporaneously by orthodontic means only. Pretreatment lateral cephalometric radiographs were scanned and analyzed. A sella turcica bridge was identified as a continuous band of bony tissue extending from the anterior cranial fossa to the posterior cranial fossa. The dimensions of the sella turcica were measured. In the group treated by combined surgical-orthodontic means, the incidence of bridging was 16.7%, whereas it was 7.3% in the orthodontics-only group (P = .012). Significant increases in the mean surface area (P = .02) and mean perimeter of the sella turcica (P = .01) were found for the combined surgical-orthodontic group compared with the orthodontics-only group. The mean interclinoid distance was significantly smaller in the surgical-orthodontic group (P = .02). These findings appear to indicate the greater likelihood of sella turcica bridging and abnormal sella turcica dimensions in subjects treated by combined surgical-orthodontic means rather than by orthodontics only.

The published experience of extra-oral endosseous craniofacial implants (EOECIs) is reviewed. The definition of osseointegration, concept of success, the relative merit of one- or two-stage implant placement, EOECI design and control of peri-abutment skin infection are discussed. A plea is made for more consistent and objective reading of clinical experience of this technique.

Records of patients undergoing the surgical removal of miniplates placed during the management of maxillofacial trauma (n=49) and orthognathic surgery (n=16) in a single unit, over a 2-year period have been analysed. Data concerning indications for plating, age and sex distribution, site of plating, time between insertion and removal, antibiotic prophylaxis, general medical factors and clinical indications for plate removal were evaluated for all patients. In addition, data for trauma patients included the site of fracture, and time delay between injury and plate insertion. Infection and/or wound dehiscence were the predominant causes for plate removal in both groups, in spite of the routine use of prophylactic antibiotics in a predominantly young, healthy cohort of patients. A removal rate of approximately 10% was found in the two groups of patients. This low rate would seem to imply that the routine removal of miniplates is not clinically indicated.

Fourteen patients or their immediate family were interviewed about their experiences of having either unilateral or bilateral external distraction osteogenesis of the mandible. The patients showed a high level of co-operation with treatment. Six of the 14 patients required repeat distractions, and had been informed and accepted that this was a possibility before the initial distraction. However, patients or their parents expressed some reservations about the extraoral distractors, which prevented them from practising their favourite sport and made them vulnerable to bullying by their friends and colleagues. Patients had moderate pain when the appliances were removed. They all expressed their satisfaction with the results and would recommend this treatment to others. Problems, including speech, eating, pain, and sleeping difficulties, were encountered by patients at all stages of treatment. Of considerable concern was the disruption of education when the child was treated during the school term.

We report our experience of endosseous implants designed to retain various types of facial prostheses that were inserted by the West of Scotland Oral and Maxillofacial Surgery Service between January 1988 and September 1998. Forty-seven patients were given a total of 150 implants, most of which were auricular (n= 85) or orbital (n= 53). The functioning success rates were 100% and 75%, respectively. Soft tissue infection was the commonest complication, and could occur at any time after exposure of the implant, suggesting that life-long follow-up is required.

Infection of soft tissues surrounding extra-oral craniofacial endosseous implants is a common clinical problem. The aim of this study was to analyse the microflora associated with such implants, in both health and disease. Eighteen patients with a total of 49 implants were studied. Each patient was seen on two occasions for both a clinical examination and for collection of microbiological samples, using swabs and paper points, from the peri-abutment soft tissues. Specimens were cultured on blood agar and on agars selective for staphylococci and yeasts. Isolates were identified and selective antibiotic susceptibility testing undertaken. No single organism emerged as a predominant cause of peri-abutment skin infection but Staphylococcus aureus, Gram-negative bacilli and yeasts were all present as potential pathogens in this context. Culture and sensitivity results should therefore guide the treatment of these infections.

ObjectivesCorrection of craniofacial microsomia (CFM) presents several challenges concerning the modality of surgical intervention. The aim of this study was to assess early and late surgical outcome, by undertaking Euclidean distance matrix analysis (EDMA) of CFM patients exhibiting an unilateral mandibular deformity that was surgically corrected by an inverted L osteotomy and autogenous bone graft.DesignLongitudinal study. Preoperative, ≈1-year postoperative and ≈3-year postoperative assessments of 14 consecutive children (mean age 9 years) with CFM. Posteroanterior cephalographs were scanned and five homologous mandibular landmarks were digitized in triplicate (< 1% digitization error). Average mandibular geometries, scaled to an equivalent size, were generated using a generalized rotational fit program (Procrustes superimposition) and subjected to EDMA.ResultsThe mean pre- and both postoperative mandibular configurations differed statistically (p < .01). Early postoperative improvements in mandibular form were noted; increases in length arising in the treated mandibular body (≈ 19%) and ramus (≈ 13%). Comparing early and late postoperative configurations, a decrease of ≈ 22% in the late postoperative mandibular body length was evident, but the ramus maintained steady vertical growth (≈ 7%). Comparing the preoperative and late postoperative configurations, the decrease observed in the mandibular body on the treated side was reduced to ≈ 8% while the ramus maintained good growth (≈ 20%) on that side.ConclusionMandibular morphology is improved significantly in CFM patients surgically treated by an inverted L osteotomy, but relapse in the mandibular body is evident after ≈ 3 years. Nevertheless, ramus growth proceeds well after the surgical reconstruction.