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Osseointegrated dental implants in the vicinity of oral squamous cell carcinoma (OSCC) will become more common given the increasing popularity of dental implants. Reports and studies of OSCC around dental implants are rare, as is the topic of how to handle OSCC surgically when implants are in contact with the tumour. In view of this uncertainty, a histological study was performed to assess tumour behaviour around implants. The aim was to determine whether an implant facilitates inward growth of the tumour and how this should be taken into account during staging and treatment planning. A total of 20 specimens were collected. The implants were macroscopically in contact with OSCC in 13 of the 20 specimens. Histologically, tumour tissue near the implant was indeed confirmed in nine of these cases. In seven cases, tumour invasion had led to resorption of the underlying jaw bone; tumour between the bone–implant interface was identified in only two of these cases, but without downward growth along the implant. In conclusion, no proof was found to confirm that the bone–implant interface is a preferred route for invasion. Therefore, dental implants in the vicinity of OSCC should not influence staging and treatment planning in this regard. [ABSTRACT FROM AUTHOR]

Although the functional benefits of implants in the rehabilitation of edentulous cancer patients are well-known, most studies report on postponed implant placement. The outcome of immediate implant placement regarding successful rehabilitation, implant loading and survival is unclear. Two hundred and seven edentulous oral cancer patients that received implants during ablative surgery at the Radboud University Medical Centre between 2000 and 2011 were included. Data regarding the oncological treatment, implant placement, follow-up and prosthodontic rehabilitation were recorded retrospectively with a follow-up period of 5–17 years. Functioning implant-retained dentures were made in 73.9% of the patients. Of the surviving patients, 81.9% had functioning dentures after 2 years and 86.3% after 10 years. Patients with ASA score 1 and younger patients were rehabilitated more frequently. The median time of functioning denture placement was 336 days after surgery, with a negative influence of postoperative radiotherapy. Implant survival was 90.7%, and was lower when the implant was placed in a jaw involved in the tumour. Immediate implant placement during oral cancer surgery led to a high number of edentulous patients rehabilitated with implant-retained dentures, which are placed at an early time. [ABSTRACT FROM AUTHOR]

The aim of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the outcomes of short dental implants (≤7 mm) versus vertical bone augmentation followed by regular dental implants (>7 mm) in the deficient posterior mandible. In total, eight RCTs (six using interpositional sandwich grafting and two using a guided bone regeneration technique) were reported in 17 articles at different time points. In the meta-analysis of the sandwich group, the relative risk (RR) for implant loss at 1 year was in favour of short implants (RR 0.41, P = 0.02), while no significant difference was found at 3 years (RR 0.65, P = 0.43), 5 years (RR 1.08, P = 0.86), or 8 years (RR 1.53, P = 0.52). The risk of complications was in favour of short implants (RR 0.34, P = 0.0002), as was the mean difference in marginal bone resorption after 1 year (−0.09 mm, P = 0.17), 3 years (−0.32 mm, P < 0.00001), 5 years (−0.65 mm, P < 0.00001), and 8 years (−0.88, P < 0.00001). The mean residual osseointegration length of the implants was between 2.94 mm and 4.44 mm in the short implants group and between 7.97 mm and 8.62 mm in the regular implants group after 5 years. In conclusion, in the deficient atrophic posterior mandible, short implants and regular implants demonstrate comparable outcomes within the first 5 years. Patients who are fit for surgery should be informed about the risks and benefits of both options. [ABSTRACT FROM AUTHOR]

For decades, hyperbaric oxygen (HBO) has often been part of the treatment of osteoradionecrosis (ORN), despite controversy in the literature about its efficacy. An online survey was conducted to investigate the use of HBO in the treatment of ORN by Dutch oral and maxillofacial surgeons and to assess their perception of its efficacy. Of the 53 Dutch oral and maxillofacial surgery units contacted, 49 (92%) replied. Thirty-five were not head and neck cancer (HNC) units or preferred partner (PP-HNC) units recognized by the Dutch Head and Neck Association. All HNC and PP-HNC units (group 1) treated ORN patients, compared to only 12 (34%) of the non-HNC units (group 2). The average number of ORN patients seen and treated was higher in group 1. The units in group 1 more often referred patients for HBO therapy (HBOT) than those in group 2 (93% vs 84%). The efficacy of HBOT in curing ORN, rated on a scale of 1 to 5 points, was 3.7 in group 1 and 3.2 in group 2. This survey shows a trend towards centralization of ORN care to more experienced units. These units tend to use HBOT in curing ORN. [ABSTRACT FROM AUTHOR]

The aim of this study was to retrospectively evaluate the perceptions of aesthetic outcome following the autologous and prosthetic reconstruction of nasal and auricular defects among patients, professionals (oral and maxillofacial surgeons and ear, nose and throat surgeons) and people unfamiliar with reconstructive surgery. The influence of anatomical subunits on the overall perception of nasal and auricular reconstructions was also determined. A total of 119 patients treated for nasal and auricular defects between 1997 and 2016, with a minimum follow-up period of 6 months, were selected, and photographs of 77 of these patients (65%) were presented in a digital survey and reviewed using a standardized questionnaire. No clinically relevant correlations were found between the age or gender of patients (as well as those of the respondents) and their scores. Prosthetic reconstructions of nasal and auricular defects were considered advantageous over autologous reconstructions in terms of the subjective aesthetic outcome in the view of the professionals, in particular oral and maxillofacial surgeons; however, the patients judged both techniques to be equally effective in terms of aesthetics. No anatomical subunits were found to have a significant impact on the overall match of a nasal or auricular reconstruction with the patient's face. [ABSTRACT FROM AUTHOR]

The purpose is to determine the accuracy of guided implant placement in the orbital, nasal, and auricular region using computer-aided designed stereolithographic skin-supported surgical templates with and without bone fixation pins. Preoperatively, cone-beam CT (CBCT) and multiple detector computed tomography (MDCT) scans were acquired from 10 cadaver heads, followed by virtual planning of implants in the orbital margin, auricular region and nasal floor. Surgical skin-supported templates were digitally designed to allow flapless implant placement. Fixation pins were used for stabilization comprising half of all templates in predetermined bone areas. The accuracy of the surgical templates was validated by comparing the achieved implant location to its virtual planned implant position by calculating the linear and angular deviations. Surgical templates with the use of bone fixation pins produced statistically significant greater implant deviations as compared to the non-fixated surgical templates. The results of this study indicate that significant deviation has to be taken into account when placing cranio-maxillofacial implants using skin-supported surgical templates. Surprisingly, the use of bone-fixated pins worsened the accuracy. [ABSTRACT FROM AUTHOR]

The current standard of care in alveolar cleft repair is timing the procedure in the mixed dentition stage and making use of autologous bone to restore the maxillary defect. Using a synthetic bone substitute bypasses the risk of donor site morbidity and reduces the operation time. In this study, the outcome of alveolar cleft repair using microporous beta-tricalcium phosphate (β-TCP) was investigated in patients with unilateral cleft lip and palate. Twenty patients were enrolled prospectively in this study, divided between two centres. Continuity of the alveolar process, recurrence of oronasal fistulas, and eruption of teeth into the repaired cleft were evaluated at 1 year postoperative. Also, cone beam computed tomography scans were analyzed using a volume-based semi-automatic segmentation protocol. No adverse events were reported. The mean residual bone volume in the repaired cleft at 1 year postoperative was 65%. There was no recurrence of oronasal fistula. Furthermore, 90% of the teeth adjacent to the cleft erupted spontaneously and all patients showed a continuous alveolar process. Secondary alveolar grafting using microporous β-TCP can safely be used in the clinical situation. Residual calcified tissue, canine eruption, and complication rates at the recipient site are comparable to those with autologous grafts. [ABSTRACT FROM AUTHOR]

This retrospective study aimed to analyse the fate of the buccal crest after immediate implant placement (IIP) through the use of cone beam computed tomography (CBCT). In 16 consecutive patients, an implant was placed in a more palatal position after extraction, thereby creating a gap of at least 2 mm between the implant and the buccal crest. Subsequently, this gap was filled with a bone substitute. Preoperatively, immediate postoperatively, and late postoperatively, a CBCT was made to measure the thickness of the buccal crest. After application of the bone substitute, the buccal crest increased in thickness from 0.9 mm to 2.4 mm (mean). At a mean of 103 weeks after IIP, late postoperative CBCT scans showed that the thickness of the buccal crest was compacted to 1.8 mm. In the same period, the height of the buccal crest increased by 1.6 mm (mean) to, on average, 1.2 mm above the implant shoulder. The aesthetic outcome was analysed using the White and Pink Esthetic Score (WES and PES). Both scored high: 8.4 and 11.8, respectively. Within the limitations of this study, the results of this IIP protocol are promising. Long-term prospective research on this topic on a large number of patients is necessary. [ABSTRACT FROM AUTHOR]

Previous research on the accuracy of flapless implant placement of virtually planned implants in the augmented maxilla revealed unfavourable discrepancies between implant planning and placement. By using the osteosynthesis screws placed during the augmentation procedure, the surgical template could be optimally stabilized. The purpose of this study was to validate this method by evaluating its clinically relevant accuracy. Twelve consecutive fully edentulous patients with extreme resorption of the maxilla were treated with a bone augmentation procedure. Virtual implant planning was performed and a surgical template was manufactured. Subsequently, six implants were installed using the surgical template, which was only supported by the osteosynthesis screws. Implant deviations between planning and placement were calculated. A total of 72 implants were installed. Mean deviations found in the mesiodistal direction were 0.817 mm at the implant tip and 0.528 mm at the implant shoulder. The angular deviation was 2.924°. In the buccolingual direction, a deviation of 1.038 mm was registered at the implant tip and 0.633 mm at the implant shoulder. The angular deviation was 3.440°. This study showed that implant placement in the augmented maxilla using a surgical template supported by osteosynthesis screws is accurate. [ABSTRACT FROM AUTHOR]

Purpose Local recurrence is a common and morbid event in patients with unresectable pancreatic adenocarcinoma. A more conformal and targeted radiation dose to the macroscopic tumor in nonmetastatic pancreatic cancer is likely to reduce acute toxicity and improve local control. Optimal soft tissue contrast is required to facilitate delineation of a target and creation of a planning target volume with margin reduction and motion management. Magnetic resonance imaging (MRI) offers considerable advantages in optimizing soft tissue delineation and is an ideal modality for imaging and delineating a gross tumor volume (GTV) within the pancreas, particularly as it relates to conformal radiation planning. Currently, no guidelines have been defined for the delineation of pancreatic tumors for radiation therapy treatment planning. Moreover, abdominal MRI sequences are complex and the anatomy relevant to the radiation oncologist can be challenging. The purpose of this study is to provide recommendations for delineation of GTV and organs at risk (OARs) using MRI and incorporating multiple MRI sequences. Methods and materials Five patients with pancreatic cancer and 1 healthy subject were imaged with MRI scans either on 1.5 T or on 3 T magnets in 2 separate institutes. The GTV and OARs were contoured for all patients in a consensus meeting. Results An overview of MRI-based anatomy of the GTV and OARs is provided. Practical contouring instructions for the GTV and the OARs with the aid of MRI were developed and included in these recommendations. In addition, practical suggestions for implementation of MRI in pancreatic radiation treatment planning are provided. Conclusions With this report, we attempt to provide recommendations for MRI-based contouring of pancreatic tumors and OARs. This could lead to better uniformity in defining the GTV and OARs for clinical trials and in radiation therapy treatment planning, with the ultimate goal of improving local control while minimizing morbidity. [ABSTRACT FROM AUTHOR]

Purpose The aims of this study were to investigate the effectiveness of cone beam computed tomography (CBCT) compared to panoramic radiography (PR), prior to mandibular third molar removal, in reducing patient morbidity, and to identify risk factors associated with inferior alveolar nerve (IAN) injury. Material and methods This multicentre, randomised, controlled trial was performed at three centres in the Netherlands. Adults with an increased risk for IAN injury, as diagnosed from PR, were included in the study. In one arm of the study, patients underwent an additional CBCT prior to third molar surgery. In a second arm of the study, no additional radiographs were acquired. The primary outcome measure was the number of patient-reported altered sensations 1 week after surgery. As secondary outcome measures, the number of patients with objective IAN injury, with long-term (>6 months) IAN injury, the occurrence of other postoperative complications, the Oral Health Related Quality of Life–14 (OHIP-14) questionnaire responses, postoperative pain (visual analogue scale score), duration of surgery, number of emergency visits, and number of missed days of work or study were scored. Results A total of 268 patients with 320 mandibular third molars were analysed according to the intention-to-treat principle. The overall incidence of IAN injury 1 week after surgery was 6.3%. No significant differences between CBCT and PR for temporary IAN injury ( p = 0.64) and all other secondary outcomes were registered. A lingual position of the mandibular canal (MC) and narrowing, in which the diameter of the MC lumen was decreased at the contact area between the MC and the roots, were significant risk factors for temporary IAN injury. Conclusion Although CBCT is a valuable diagnostic adjunct for identification of an increased risk for IAN injury, the use of CBCT does not translate into a reduction of IAN injury and other postoperative complications, after removal of the complete mandibular third molar. In these selected cases of a high risk for IAN injury, an alternative strategy, such as monitoring or a coronectomy, might be more appropriate. ( http://clinicaltrials.gov , NCT02071030 ). [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse changes in the volume of the chin after harvest of a bone graft for secondary reconstruction of an alveolar cleft. Cone-beam computed tomographic (CT) scans of 27 patients taken preoperatively, and immediately and one year postoperatively, were analysed, and 3-dimensional hard-tissue reconstructions made. The hard-tissue segmentation of the scan taken one year postoperatively was subtracted from the segmentation of the preoperative scan to calculate the alteration in the volume of bone at the donor site (chin). A centrally-orientated persistent concavity at the buccal side of the chin was found (mean (range) 160 (0-500) mm 3 ). At the lingual side of the chin, a central concavity remained (mean (range) volume 20 (0-80) mm 3 ). Remarkably, at the periphery of this concavity there was overgrowth of new bone (mean (range) volume 350 (0-1600) mm 3 ). Re-attachment of the muscles of the tongue resulted in a significantly larger central lingual defect one year postoperatively (p = 0.01). We also measured minor alterations in volume of the chin at one year. Whether these alterations influence facial appearance and long term bony quality is to be the subject of further research. [ABSTRACT FROM AUTHOR]

A new method is presented in which the osteosynthesis screws from a first stage bone augmentation of the maxilla are used to stabilize the surgical template during implant placement in the second stage. This method was evaluated in one patient and the results compared to those of previous studies. The technique presented reduces the deviations between implant planning and the final implant position due an optimal fit of the surgical template. [ABSTRACT FROM AUTHOR]

The results of a retrospective study on 24 patients who underwent a Le Fort I osteotomy to improve the condition for implant insertion are presented. They all had an edentulous maxilla, Cawood and Howell class VI. Bone grafts were taken from the anterior or posterior iliac crest and implants were placed between 3 and 6 months after the osteotomy. The follow-up period ranged from 5 to 18 years. Initial complications occurred in seven patients in whom small bony defects were present at the time of the implant insertion procedure. The position of the advanced and downward grafted maxilla remained stable over the years. A total of 135 implants were initially inserted, of which 34 failed over the years. Ten implants were inserted to compensate for lost ones, of which only one failed. The screw implants tended to do better than the cylindrical implants. Two patients lost all implants; they had undergone previous surgery affecting the sinus and were also heavy smokers. The remaining 22 patients were satisfied with their treatment as shown by visual analogue scale scores. The results presented are in keeping with those of other reports and underscore the viability of the procedure. [ABSTRACT FROM AUTHOR]

We present the preliminary results of a study involving a group of consecutive patients who underwent lower border onlay grafting, limited to the symphyseal area, in preparation for implant insertion. This technique allows for maximum-sized implants, followed by prosthetic rehabilitation. The main advantage of this method is the minimal risk of damage to the mental nerve. Sixteen patients were followed for a period of 6 months to 4 years and all were free of neurosensory disturbances. Eight had a removable overdenture placed and were satisfied with the result. This surgical approach allows the patient to wear their dentures during the healing period. A further advantage of lower border grafting over intraoral upper border grafting is that mucosal dehiscences are not seen. [ABSTRACT FROM AUTHOR]

Abstract: As with other techniques, vertical distraction osteogenesis (VDO) can also induce complications. The case of a patient with a residual alveolar ridge in the symphyseal area of 8mm is presented. After performing VDO, the patient returned at 1-day postoperatively complaining of pain and dislocation of the distractor device, due to a fracture of the lower mandibular segment on the right side. After removal of the distractor device and application of osteosynthesis plates, the patient returned 2 weeks later due to a second fracture of the lower segment, yet on the left side. After removing the osteosynthesis material, stabilization of the mandible was achieved with an acrylic splint, which was fixated with peri-mandibular wiring. Finally, reconstruction was accomplished by lower border onlay grafting, limited to the symphyseal area, in preparation for implant insertion. Ultimately, after a healing period of 5 months, two endosseous implants were installed. The patient's function has remained satisfactory for 3 years. Reinforcement of the extreme resorbed edentulous mandible after fracture healing by lower border bone augmentation can be a reliable method to allow implant installation in a second stage. [Copyright &y& Elsevier]

Abstract: In a retrospective study, two mandibular prosthetic rehabilitation strategies supported by implants in oral cancer patients were evaluated: implants placed in the non-resected edentulous symphyseal area during ablative surgery (DAS implants); or at a later stage (postponed (P) implants). Medical files of patients from two head-neck oncology groups from 2000 to 2005 were screened for study inclusion. DAS protocol was used in one group and P protocol in the other. After a 5 year follow-up of 261 edentulous patients with oral cancer in the second group, P implants were placed in 27 patients to support an overdenture. Of the 249 edentulous patients in the first group, 82 patients were given an implant supported overdenture using the DAS implant protocol. Regarding implant loss, no statistically significant differences were seen between the DAS and P implants. In the DAS group, more patients benefited from an implant-supported lower overdenture (39 versus 11%, respectively), and they received their overdenture on average 20.0 months sooner (sd=11.01, p <0.001) after ablative surgery. 17.1% of DAS implants and 4.6% of P implants were never loaded due to tumour and patient related factors including unfavourable implant soft tissue, tumour recurrence near the implant, or radiotherapy induced trismus. [Copyright &y& Elsevier]

Abstract: To allow for implant placement in severe atrophic edentulous mandibles, distraction osteogenesis can be used to gain sufficient bone height. The efficacy of extra-osseous and intra-osseous devices is evaluated. In this retrospective study, 45 patients treated with an extra-osseous device (EOD) were compared with 43 patients treated with an intra-osseous device (IOD). From a statistical point of view, both patient groups were comparable for age and sex ratio. The IOD group gained more bone height (9.8mm) than the EOD group (6.0mm). A significantly higher degree of backward tilting of the device was observed in the EOD group (12.1°), compared with the IOD group (3.0°). There were also significantly more fractures of the basal bone segment and sensory disturbances of the chin area in the EOD group than in the IOD group. The IOD group scored significantly better on bone height gained, backward tilting of the device, occurrence of fractures, and postoperative sensory disturbances. Despite the fact that the mean preoperative bone height for the IOD group was substantially higher (18.6mm) than for the EOD group (11.9mm), it may be concluded that for augmentation procedures of the edentulous mandible, the IOD is more favourable. [Copyright &y& Elsevier]

Abstract: This prospective study evaluated the role of cone beam computed tomography (CBCT) in the treatment of patients with impacted mandibular third molars at increased risk of inferior alveolar nerve (IAN) injury. Subjects with an increased risk of IAN injury, as diagnosed on panoramic radiographs, were enrolled in this study and underwent additional CBCT imaging. Two oral maxillofacial surgeons independently planned the surgical technique and estimated the risk of IAN injury on panoramic radiographs and on CBCT images. A test of symmetry and the McNemar test were executed to calculate the differences between the two imaging modalities. The study sample comprised 40 patients (mean age 27.6 years) presenting 53 mandibular third molars. Risk assessment for IAN injury based on panoramic radiography compared with CBCT imaging differed significantly (P <0.005). After reviewing the CBCT images, significantly more subjects were reclassified to a lower risk for IAN injury compared with the panoramic radiograph assessments. This change in risk assessment also resulted in a significantly different surgical approach (P <0.03). The results of this study show that CBCT contributes to optimal risk assessment and, as a consequence, to more adequate surgical planning, compared with panoramic radiography. [Copyright &y& Elsevier]

Abstract: Alveolar reconstruction of bony defects in cleft lip and palate patients is a widely accepted treatment regimen for which multiple donor sites can be used. For 25 years, autogeneous bicortical mandibular symphyseal bone grafts have been used at the authors’ centre. In cases in which the alveolar defect was too large to match the volume of the mandibular symphyseal bone transplant, β-TCP granules were packed against the bone transplant to fill the defect completely. In a retrospective study, 18 patients, who were treated with mandibular symphyseal bone wrapped in β-TCP granules, were compared with 29 patients, who were treated with mandibular symphyseal bone only. To assess alveolar height, occlusal radiographs were taken directly postoperatively and 1 year later. Mean alveolar bone loss was calculated and compared between groups using Student''s t-test and linear regression analysis. No statistically significant difference in alveolar height was found between the two groups. It was concluded that mandibular symphyseal bone grafts enriched with β-TCP granules can be used successfully in cases in which the alveolar cleft is too large to be grafted with mandibular symphyseal bone alone. [Copyright &y& Elsevier]

Abstract: Transplants from the anterior iliac crest are used for most reconstructive procedures in cranio-maxillofacial surgery. The advantages are easy accessibility, the ability to work in two teams and the amount of corticocancellous bone available; disadvantages are postoperative pain and gait disturbances. To reduce donor-site pain, the effect of a single dose of bupivacaine (10 cc of 2.5mg/cc with 1:80.000 epinephrine) was studied. 200 consecutive patients, who underwent anterior iliac crest bone harvesting for reconstructive procedures, were randomly divided into those receiving bupivacaine and those not. They completed a standardized questionnaire. Patients scored the intensity of the pain and difficulties walking at different times with a visual analogue scale. They recorded analgesics used. 98 questionnaires were eligible for analysis. No differences between the bupivacaine and the control group were detected for postoperative pain and gait disturbance. There is no support for administration of a single dose of bupivacaine to reduce pain in the first postoperative days. The surface area of the removed bone had a significant influence on pain and walking; pain is related to the local osseous damage or periosteal stripping rather than to the length of incision or the operation time. [Copyright &y& Elsevier]

Abstract: The results on 32 consecutive patients, who underwent bone grafting prior to implant surgery, are presented. The grafts were taken from the horizontal part of the mandible, including the full height of the buccal cortico-cancellous plate and were used to reconstruct alveolar defects or to augment sinus floors. 3–5 months postoperatively, 99 implants were inserted in 43 onlay grafts and in 17 sinus floor augmentations. The follow-up ranged from 2–6 years post implant insertion. Parameters examined included: healing of donor site and bone grafts, implant survival, peri-implant condition, donor site morbidity and patient satisfaction. This study indicates that with one full height ramus graft, alveolar defects comprising a bicuspid–molar area, can be augmented. The grafted volume is also sufficient to augment one sinus floor. The implant survival rate (99%) compares well with studies using iliac crest or skull bone. Postoperative complaints were minimal, resulting in extremely high patient satisfaction (97%). [Copyright &y& Elsevier]

Abstract: The aim of this study was to describe the surgical and functional complications following superiorly based posterior pharyngeal wall (SBPP) flap surgery. Records of 130 patients with velopharyngeal insufficiency (VPI) who had undergone SBPP flap surgery as a secondary procedure to reduce nasal resonance in speech were reviewed. Complications were defined as the incidence of revisional surgery required to obtain a more satisfactory result. 20 patients (15%) required revisional surgery. In 4 patients (3%) early revisional surgery was indicated to treat surgical complications (1 postoperative bleeding, 3 flap dehiscences). In 16 patients (12%) late revisional surgery was indicated to achieve a better functional result with regard to nasal resonance in speech. The low incidence of surgical complications indicates that SBPP flap surgery is a safe procedure. After SBPP flap surgery, a satisfactory functional result with respect to nasal resonance was obtained in 88% of patients. This result was improved after revisional surgery. The hypothesis that the patients of an experienced surgeon have fewer complications and better functional results than those of a less experienced one was tested. The individual skill of the surgeon rather than their experience led to a better functional result. [Copyright &y& Elsevier]

Abstract: This study investigated the diagnostic accuracy of cone beam computed tomography (CBCT) compared to panoramic radiography in determining the anatomical position of the impacted third molar in relation with the mandibular canal. The study sample comprised 53 third molars from 40 patients with an increased risk of inferior alveolar nerve (IAN) injury. The panoramic and CBCT features (predictive variables) were correlated with IAN exposure and injury (outcome variables). Sensitivity and specificity of modalities in predicting IAN exposure were compared. The IAN was exposed in 23 cases during third molar removal and injury occurred in 5 patients. No significant difference in sensitivity and specificity was found between both modalities in predicting IAN exposure. To date, lingual position of the mandibular canal was significantly associated with IAN injury. CBCT was not more accurate at predicting IAN exposure during third molar removal, however, did elucidate the 3D relationship of the third molar root to the mandibular canal; the coronal sections allowed a bucco-lingual appreciation of the mandibular canal to identify cases in which a lingually placed IAN is at risk during surgery. This observation dictates the surgical approach how to remove the third molar, so the IAN will not be subjected to pressure. [Copyright &y& Elsevier]

Abstract: Reconstruction of a severely atrophied maxilla by sinus augmentation with a mixture of hydroxylapatite (HA) granules and autologous cancellous bone is claimed to be a predictable means to facilitate implant placement. To the authors’ knowledge, this is the first human histological case report of plasma-sprayed HA-coated implants being loaded after sinus augmentation was performed with a mixture of HA granules and autologous bone. A patient gave consent for post-mortem analysis of his upper jaw, Ten years after successful reconstruction of his maxilla and functional implant loading, the region of augmentation showed stable contours both radiographically and histologically. In 10 years, the granules had only minimally degraded. HA granules outlined the grafted area to protect it against resorption. The plasma-sprayed HA coating on the dental implant was intact, showing 48% contact with the surrounding bone. [Copyright &y& Elsevier]

Abstract: To improve the starting point for placement of dental implants, 45 patients suffering from atrophied edentulous mandibles, with a vertical height varying between 7.3 and 15.8mm, were treated by alveolar vertical distraction osteogenesis (VDO). The mean follow-up period was 3 years, ranging from 1 to 7 years. Associated complications, as occurred during instalment of the distractor device, VDO period and consolidation phase, and also after dental implant placement, were evaluated. Observed complications were: early fractures (2%), late fractures (17%), bleeding or haematoma (4%), infections (6%), skin perforation (2%), mucosal dehiscence (8%), sensory disturbances (28%), sagging chin (13%) and failure of dental implants (13%). In 10 patients 2 complications and in 1 patient 3 complications were monitored. All complications occurred in the first year. It is concluded that VDO to restore vertical bone height in patients with mandibular atrophy is a surgically delicate technique with a high risk of various complications. The likelihood of the most striking complication, namely fracture occurrence, increases with decreasing residual bone height. [Copyright &y& Elsevier]

Abstract: Surgical treatment of malignancies involving the oral cavity often results in an altered anatomical situation, which may severely hamper oral function. Postoperative radiotherapy resulting in reduced salivary secretion further worsens functions such as speech, chewing (mastication) and swallowing. In order to improve oral functioning, the use of dental implants was proposed. To reconstruct the edentulous mandible, especially in cases involving postoperative irradiation, implant-borne prosthetic construction on four permucosal implants has been advocated, but this treatment concept has some practical drawbacks. As the chewing force is reduced as a result of irradiation of the masticatory muscles, it is hypothesized that a fixed prosthetic construction on only two implants is a feasible alternative. Up until now 10 patients have been treated successfully according to this concept at the authors’ clinic. [Copyright &y& Elsevier]