Retrospective review of 78 rehabilitated head and neck postoncological patients: a new classification method

BACKGROUND

Numerous studies have been published about the prosthetic rehabilitation of the postoncological maxillo-facial patient, but the guidelines that emerge lack a correlation between the anatomical classification of the treated site, which generally is preparatory upon surgery, and the type of prosthetic rehabilitation appropriate to the new anatomical and functional condition. With this correlation, it would be possible to obtain a multidisciplinary and predictable therapeutic process, able to identify from the beginning the best type of prosthetic rehabilitation.

METHODS

The authors analyzed a sample of 78 patients treated in the Maxillofacial Surgery Unit of "Sapienza" University of Rome for a tumor of the head and neck area, and at a later stage prosthetically rehabilitated in the years from 2010 to 2013 in the Prosthetic Rehabilitation Unit of the same University because of the consequences of the ablative surgery. After having analyzed data concerning the treatment of the maxillofacial tumor, Authors classified the kind of prosthetic rehabilitation. Removable prosthesis was chosen in 18 cases, while implant (or teeth)-supported rehabilitation was performed in 60 cases.

RESULTS

Authors correlated the kind of surgical reconstruction to the prosthetic rehabilitation performed. In the maxilla removable prosthesis was chosen in 8 cases, while implant supported rehabilitation was performed in 18 cases. In the mandible 10 cases were rehabilitated through a removable prosthesis and 42 through a teeth or implant supported prosthesis.

CONCLUSIONS

It is evident the need to perform a careful evaluation of the patient, in order to identify the best possible prosthetic rehabilitation.

[Nickelid titanium mesh for orbital floor reconstruction]

The treatment plan for patients with mid-face fractures was presented in this article. In maxillofacial department of the I.M. Sechenov First Moscow State Medical University we used nickelid titanium mesh for reconstruction of the orbital floor. The clinical case with good result of treatment was presented here.

[Maxillary brown tumor revealing primary hyperparathyroidism: apropos of a case and review of the literature]

Les tumeurs brunes sont des lésions ostéolytiques rarement révélatrices des hyperparathyroïdies. Elles surviennent habituellement au stade terminal de l'hyperparathyroïdie primaire ou secondaire. Durant les 3 dernières décennies, le diagnostic des hyperparathyroïdies est le plus souvent fait à la phase asymptomatique grâce aux dosages systématiques du calcium et l'avènement des nouvelles techniques, de dosage de la parathormone. Nous rapportons l'observation d'une patiente avec hyperparathyroïdie primaire révélée par une tumeur du maxillaire, dont la TDM avait mis en évidence un processus ostéolytique agressif. L'intervention chirurgicale a consisté en une maxillectomie droite avec reconstruction. Le résultat anatomo-pathologique a conclu en une tumeur à cellule géantes bénigne du maxillaire. Le diagnostic de tumeur brune a été évoqué et confirmé après la réalisation d'un bilan phosphocalcique qui a mis en évidence une hypercalcémie, avec une hypophosphorémie. La recherche étiologique a objectivé à la TDM cervicale un processus en situation rétro et infra thyroïdienne droite en faveur d'un adénome parathyroïdien. Le dosage de la parathormone: 322 pmol/L a confirmé le diagnostic. Nous rappelons à travers cette observation la difficulté d’établir un diagnostic correct chez les patients avec un processus ostéolytique du maxillaire et la nécessité de rechercher une hyperparathyroïdie devant une lésion à cellules géantes vue le caractère insidieux de cette endocrinopathie.

[Perspectives of use of polytetrafluoroethylene with nanostructured surface in dentistry]

The perspectives of use of porous polytetrafluorethilen (PTPE) with modified surface combined with mesenchymal stem cells for tissue-engineering constructions were studied. The paper also describes the mode of PTPE surface modification consisting in nanostructured metallic or ceramic layer application resulting in biocompatibility and surface adhesion rates increase. The magnetic atomizing of Ti and Ti-Ca-P-C-O-N nanolayers enhances the material integration potential as well as adhesion rates thus making it perspective when combined with mesenchymal stem cells for bone defects plasty.

Maxillary sinus floor augmentation using a nano-crystalline hydroxyapatite silica gel: case series and 3-month preliminary histological results

The aim of this case series is to histologically examine a new hydroxyapatite in sinus lift procedure after 3 months. Ten 2-stage sinus lifts were performed in 10 healthy patients having initial bone height of 1-2mm and bone width of 5mm, asking for a fixed implant-supported rehabilitation. After graft material augmentation, a rough-surfaced mini-implant was inserted to maintain stability of the sinus widow. A bioptical core containing a mini-implant was retrieved 3 months after maxillary sinus augmentation with NanoBone(®) and processed for undecalcified histology. From the histomorphometric analysis, NanoBone(®) residuals accounted for the 38.26% ± 8.07% of the bioptical volume, marrow spaces for the 29.23% ± 5.18% and bone for the 32.51% ± 4.96% (new bone: 20.64% ± 2.96%, native bone: 11.87% ± 3.27%). Well-mineralized regenerated bone with lamellar parallel-fibred structure and Haversian systems surrounded the residual NanoBone(®) particles. The measured bone-to-implant contact amounted to 26.02% ± 5.46%. No connective tissue was observed at the implant boundary surface. In conclusion, the tested material showed good histological outcomes also 3 months after surgery. In such critical conditions, the use of a rough-surfaced mini-implant showed BIC values supposed to be effective also in case of functional loading. Although longer follow-up and a wider patient size are needed, these preliminary results encourage further research on this biomaterial for implant load also under early stage and critical conditions.

[Rehabilitation by hollow obturator prosthesis immediately after total maxillectomy for malignant tumor]

OBJECTIVE

The feasibility and clinical effects of hollow obturator prosthesis for the repair of maxillofacial defect immediately after maxillectomy for cancer were assessed.

METHODS

Thirteen patients with T3-4aN0M0 maxillary neoplasm were treated by the prostheses immediately after maxillectomy. According to the 3D-CT reconstruction of nasal sinus, the 3D stereoscopic prototype was constructed before the surgery. Simulating surgery with Surgicare 5.0 software and then the prosthesis 3D stereoscopic model was shaped. The prosthesis was made quickly and precisely with methacrylate resins according to the model and the print mold before surgery, with supplementary tooth at the bottom of prosthesis. In the surgery, the prosthesis was installed instantly after maxillectomy. The patients were followed up at 1, 3 and 6 month after the surgery, respectively. The facial features and the pronunciation clarity were examined and the questionnaires were carried out in the patients, with comparation by paired t-test. The hollow obturator prosthesis would be replaced by permanent prosthesis made of methacrylate resins at 6 month after the surgery.

RESULTS

The hollow obturator prostheses were installed accurately and maxillofacial defects were repaired immediately after maxillectomy in the 13 patients. Postoperative follow-up showed there were significant differences in eyeball sagging (t = 4.67, P < 0.05), mid-facial region collapse (t = 5.67, P < 0.05), and pronunciation clarity (t = 16.38, P < 0.05) between patients with and without prostheses. Questionnaires showed that all the patients were satisfied with the retention of prostheses, the improvement of appearance, the improvement of the symptom of water choking and speech definition. Six months after the surgery, the hollow obturator prostheses were replaced smoothly by permanent prostheses in 11 of the 13 patients.

CONCLUSION

The precise and instant repair of maxillofacial defect by prosthesis after maxillectomy can improve survival quality of patient.

Multiple retentive means for prosthetic restoration of a large facial defect - a case report

A 70-year-old man who suffered from extensive extra and intraoral defects was rehabilitated with a prosthesis using multiple retaining means. The treatment was performed in two parts: externally involving the construction of an episthesis supported only by the remaining intact boundaries of the defect and retained by mini-dental implants and spectacle frame with a modified ear hook; and intraorally by an acrylic resin obturator to restore the function of the hemi-sectioned hard and soft palate. The episthesis was securely retained with minimal movement and/or dislodgment of the prosthesis during function. Multiple retentive techniques may be used to fix heavy external prostheses as an alternative to conventional implants or biological adhesives.

[Clinical application of bone regeneration by in vivo tissue engineering]

With regard to the graft materials, cortical bone block, vascularized bone flap and particulate cancellous bone and marrow (PCBM) have been used for the reconstruction of maxillofacial skeleton. Needless to say, the aim of cortical bone block and vascularized bone flap transfer is the transplantation of bony tissue of its own. On the other hand, the main objective of PCBM grafting is the transplant of osteogenic stem cells derived from uncommitted marrow mesenchymal cells. After PCBM grafting, active new bone formation occurs from osteogenic stem cells followed by bone remodeling and replacement of host bone. This process means that PCBM grafting is the method of bone regeneration that is based on in vivo tissue engineering. In this paper, clinical application of PCBM grafting for the reconstruction of maxillofacial skeleton is introduced by showing the repair of maxillary bony defect of cleft lip and palate patients, alveolar ridge augmentation and the reconstruction of large mandibular segmental defects.

Assessment of the quality of life in patients with oral cavity and jaw cancer in three regions of Bulgaria

PURPOSE

The aim of the present study was to assess the quality of life (QoL) in 103 patients with oral cavity and jaw cancer, using an original rating scale.

PATIENTS AND METHODS

In order to assess the QoL in such patients an original rating scale was developed and validated. For statistics alternative analysis, non parametric tests, correlation analysis, and graphic analysis were used.

RESULTS

Most patients were rated as grade III or IV according to the 5-grade scale (grade IV the most severe). Their QoL was significantly deteriorated, resulting in depression and despair. Reconstruction and prosthesis implantation and social rehabilitation were needed in these patients. QoL was assessed in 19 patients prior to and following prosthesis implantation. Prior to implantation most patients were rated as grade III or IV, whereas the majority of them were rated as grade 0 or 1 following prosthesis implantation. Prosthesis implantation contributed to improvement of speaking and feeding and elimination of disfigurement.

CONCLUSION

After assessment of QoL, patients rated as grade III or IV should have access to complex medical management, including prosthesis implantation and social rehabilitation.

The Role of Functional Orthodontic Stress on Implants in Residual Alveolar Cleft

BACKGROUND

The most widely accepted protocol for alveolar cleft reconstruction is repair during the mixed dentition stage (age, 9 to 11 years), before eruption of the canine teeth. Alveolar bone grafting should not be considered as an isolated therapy but always as an integrated part of comprehensive orthodontic treatment.

METHODS

The authors evaluate the results of transitional secondary osteoplasty, comparing the use of autogenous cancellous bone versus heterogenetic implants, in patients with unilateral complete clefts who did or did not undergo orthodontic treatment. From 1990 to 1994, 48 patients aged between 9 and 11 years with unilateral alveolar cleft underwent alveolar grafting by transitional secondary osteoplasty. In 30 patients (group A), autogenous cancellous bone was used, and in 18 patients (group B), a heterogenetic implant consisting of demineralized bone powder containing bone morphogenetic protein and hydroxylapatite was used.

RESULTS

Twenty-two patients in group A and 12 patients in group B underwent orthodontic treatment. After 10 to 12 years of follow-up, the clinical and radiographic examinations revealed that the best alveolar bone repair results were obtained using autologous bone graft in association with orthodontic treatment. Also, in the patients who underwent heterogenetic implantation, the orthodontic treatment clearly improved the quality of the osteoplasty.

CONCLUSIONS

The essential conditions for a successful osteoplasty include meticulous operative technique and orthodontic treatment. The latter plays an essential role at several stages of development in children with clefts. The "functional stress" on the autologous or heterogenetic implant exerts a decisive influence on the quality and volume of the osteoplasty, preventing progressive resorption.

Post-operative re-construction of dentoalveolar tissue and the mandible and maxillae using prosthetic therapy

OBJECTIVE

To determine the range of ablative surgery and rehabilitative procedures performed on maxillofacial structures.

DESIGN

A retrospective descriptive study.

SETTING

University of Nairobi Dental Teaching Hospital.

SUBJECTS

Patients operated on at the institutions theatre, and followed up at the University of Nairobi Dental Teaching Hospital Oral Surgery Outpatient Clinic during the period February 1996, August 1998.

RESULTS

Forty four patients underwent ablative surgery during the study period. Complete records were available for 38 patients, 27 females and 11 males aged 10 to 79 years (mean 32.6 years). Surgical procedures performed included: partial mandibulectomy, marginal mandibular resection, subtotal maxillectomy, sequestrectomy and enucleation. Six (15.8%) patients who underwent mandibular resection had rigid bone plating. Five (13.2%) patients who had maxillary involvement were given surgical obturators post-operatively with one receiving a complete denture after full recovery. A total of 22 (57.9%) patients who would have reaped benefits from prostheses therapy received none. Individual patient follow-up periods ranged from seven days for two patients who had cyst enucleation to two years for three cases with ameloblastoma, and two cases with squamous cell carcinoma.

CONCLUSION

It is concluded that prosthetic rehabilitation of patients undergoing extensive surgery at the University of Nairobi Dental Teaching Hospital is largely inadequate.

Rehabilitation of a bilateral maxillectomy patient with a free fibula osteocutaneous flap*

Rehabilitation of patients who have undergone bilateral maxillectomy is difficult because of extensive loss of bone and soft tissue. In this clinical report, prosthodontic rehabilitation of oral function in a bilateral maxillecitomy patient combined with a new fibular osteocutaneous flap, which was designed to have two oronasal slits for the retention of an obturator prosthesis, was described. A 58-year-old man with a maxillary alveolar carcinoma underwent bilateral maxillectomy. The defect was reconstructed using a vascularized fibular bone wrapped circumferentially with a peroneal flap, which was fixed with miniplates between the right malar prominence and cut edge of the left zygoma remaining two slits anterior and posterior to the graft. Two and half weeks after the surgery, a delayed surgical obturator was delivered and an obturator prosthesis was delivered 6 weeks after the surgery. This obturator prosthesis could be extended into the slits to engage the tissue undercuts, and was stable during use. Mastication, deglutition, articulation and the mid-facial profile of the patient were rehabilitated. After installation of the obturator prosthesis, relining of the prosthesis base was carried out alongside the healing process of the graft, and adjustment of occlusions and high-pressure spots was carried out. No clinical disorders were observed either in the grafted tissue or the obturator prosthesis with a 3-year prognosis. Newly designing a fibular osteocutaneous flap combined with tissue-borne obturator prosthesis is one successful approach to the restoration of oral function, and increases the patient's quality of life after bilateral maxillectomy.

Successful upper alveolar reconstruction for gingival cancer using a fibular osteoadipofascial flap without osseointegrated implants

An upper alveolar skeletal reconstruction with closure of the palatal fistula using an osteocutaneous free flap is considered an ideal reconstructive strategy after curative surgery for cancer of the lower maxilla. Although installation of osseointegrated implants into the bone has advantages for utilizing a dental prosthesis, it is often time and cost prohibitive. In the case of 1 patient, we reconstructed and fit the patient with a conventional denture, eliminating the need for installation of osseointegrated implants. The patient underwent upper alveolar reconstruction using a fibular osteoadipofascial flap, followed by a skin graft for creation of an alveololabial sulcus. It was then possible for the patient to wear a conventional denture without implants. One explanation for this success is that the regenerated mucosa on the adipofascial flap and skin graft was immobile, which allowed it to serve as a base for the dental prosthesis. The alveololabial sulcus that had been constructed kept the denture in place. This reconstruction confirmed that a fibular osteoadipofascial flap might be a useful choice in restoring a natural upper alveolar osseous and soft tissue structure.

Systematic review of the evidence supporting intra-oral maxillofacial prosthodontic care

The literature on maxillofacial prosthodontics may be considered to be dominated by articles describing case reports or case series. Prospective, well-controlled clinical trials are scarce owing to the inherent difficulty of performing such trials in patients suffering from oral cancer. The aim of this study was to perform a systematic review of the literature relating to intra-oral maxillofacial prosthodontics based on the principles of evidence-based dentistry. A detailed report of the findings is presented and critically assessed and a discussion of the outcome in respect to the various confounding factors is carried out. Finally, suggestions for future research in the field of maxillofacial prosthodontics are made.

Residual facial disfigurement after the ablative surgery of a lachrymal gland carcinoma: a clinical report of the prosthetic rehabilitation

Facial disfigurement after ablative surgery of a massive adeno-carcinoma of the lachrymal gland is described. A rehabilitation with a maxillofacial prosthesis was proposed to restore the aesthetic appearance of the patient without inserting craniofacial implants. Retention of a maxillofacial prosthesis, that is not anchored to implants, depends on the use of adhesives or on mechanical devices like glasses. This clinic report describes a residual anatomic defect which allowed for the double choice of wearing the facial prosthesis both with or without glasses. A retentive backside of the prosthesis was developed to engage the facial defect undercuts, which enhanced retention when the patient used the skin glue without glasses. A unique foam silicone was utilized to reduce the weight of the prosthesis and to permit its retention only by skin adhesive.

Extra-oral craniofacial endosseous implants and radiotherapy

This paper discusses the use of extra-oral endosseous craniofacial implant (EOECI) therapy in irradiated bone. The survival rate of EOECIs in irradiated bone is reviewed and the controversy over the optimal time prior to place implants is described. The advantages and disadvantages of pre- and post-implant radiotherapy are addressed. The EOECI rehabilitation and osteoradionecrosis and the evidence of the potential role of hyperbaric oxygen are reviewed. Strategies for improving the clinical outcome of EOECIs are suggested.

Advances in head and neck reconstruction

There are numerous advances that have taken place over the last several years in head and neck reconstruction. In this article, the author has outlined three exciting developments. The first is in the area of palatomaxillary reconstruction using free tissue transfer. In select cases, depending on the nature of the defect, soft tissue flaps have been highly successful. However, in more extensive defects, the author chooses to transfer vascularized bone composite flaps to achieve successful dental restoration as well as closure of the palatal defect. Sensory restoration through the use of sensate flaps has been a topic of considerable controversy. The author presents his experience with three patients who underwent a unique reconstruction of the laryngopharynx that has demonstrated conclusively that targeted sensory restoration can be achieved through neural anastomoses. By anastomosing the sensory nerve to the superior laryngeal nerve, there are implicit physiologic implications with respect to the feedback that is achieved and its role in achieving glottic closure during deglutition. Extensive laryngeal reconstruction with subglottic involvement can be a very challenging problem. The author describes a new technique using vascularized tracheal autografts with the thyroid gland as a carrier. This provides the necessary ingredients for transferring a cartilaginous infrastructure within a thin layer of vascularized mucosa to restore the framework and the lining to the laryngotracheal region. Three patients have been restored who had extensive glottic and subglottic stenoses that have since been decannulated and are successfully eating as well as speaking. In addition, the author feels that this is a very promising technique for the management of chondrosarcomas, in which a significant portion of the cricoid arch requires reconstruction.

Maxillofacial rehabilitation of a large facial defect resulting from an arteriovenous malformation utilizing a two-piece prosthesis

Large facial defects involving the oral cavity can be difficult to restore prosthetically because of a lack of anatomic undercuts, limited means of retention, mobility of soft tissue margins, and the weight of the prosthesis. Use of skin adhesives may be precluded because of the presence of persistent moisture and saliva. The maxillofacial rehabilitation, including the design and fabrication of a 2-piece silicone prosthesis retained by the teeth, of a patient with a large facial defect as a result of treatment for an arteriovenous malformation is described. The pathogenesis and therapeutic alternatives for arteriovenous malformations is also discussed.

Comparison of maxillary implant-supported prosthesis in irradiated and non-irradiated patients

In order to investigate the influence of radiation therapy after the treatment of maxillary implant-supported prostheses, 27 patients received a total of 131 implants in maxilla after oral cancer treatment and/or reconstructive surgery. Among them, 25 received maxillary implant-supported prostheses. The cumulative survival rates of implants and prostheses were evaluated by the product-limit-estimates method according to Kaplan-Meier. The cumulative survival rate of implants and prostheses in irradiated patients was compared with that in non-irradiated patients by statistical Log-rank test. The results showed that 112 implants were observed after implant loading. The implants cumulative survival rate was approximately 65% for overall patients. The cumulative prosthesis successful rate was approximately 88% for all 25 patients. Log-rank test analysis revealed that there was a significant difference in cumulative implants survival rates between non-irradiated and irradiated maxillary bone (P < 0.01). It was concluded that the implants and prostheses in irradiated patients have significantly lower survival rates than in non-irradiated patients.

[Application of prosthetic replacement for bilateral maxillectomy defect]

A 59-year-old woman with large hard palate cancer underwent surgical resection. We constructed a maxillary prosthesis to be connected to the patient's mandibular denture. Bilateral maxillectomy resulted in total loss of the hard palate and bilateral alveolar and partial loss of the soft palate. A obturator prosthesis was prepared beforehand to fit the surgical cavity. The patient recovered functional speech and swallowing at a relatively early stage, achieving satisfactory cosmetic results.

Prosthetic rehabilitation of a patient following maxillectomy with orbital exenteration

The maxillectomy patient despite the drastic nature of the procedure can often be restored to an acceptable aesthetic and functional condition. The treatment of maxillectomy patient presents an excellent opportunity for the surgeon and the prosthodontist to coordinate their efforts to enhance the patient's rehabilitation. This clinical report describes the prosthetic rehabilitation of a patient with squamous cell carcinoma of the right maxilla requiring maxillectomy with orbital exenteration.

Preshaped hydroxyapatite tricalcium-phosphate implant using three-dimensional computed tomography in the reconstruction of bone deformities of craniomaxillofacial region

We prepared solid life-sized models and templates of implants based on three-dimensional computed tomography data in six cases with a bone deformity of the craniomaxillofacial region. After simulation surgery using these models and templates, the preshaped hydroxyapatite-tricalcium phosphate (HAP-TCP) implants were prepared to fill in the facial bone defects, and implantation was performed. Consequently, implants fitted the individual bone defects, and satisfactory facial contouring was obtained in five cases. In one case with severe cutaneous scarring in the grafted site, it was necessary to reduce the volume of the preshaped HAP-TCP implant during surgery. In conclusion, the three-dimensional, solid, life-sized model and template are useful for preoperative detailed simulation, and the use of preshaped HAP-TCP implants based on the template probably contributes to successful reconstruction of complex facial bone deformities and to the reduction of surgical invasion, resulting in achievement of better results.

Prosthodontic guidelines for surgical reconstruction of the maxilla: a classification system of defects

Surgical reconstruction of maxillectomy defects has been described as an alternative to prosthetic rehabilitation to close the oral cavity. Advancements in microvascular surgical techniques require comprehensive treatment planning guidelines for functional rehabilitation. This retrospective study evaluated acquired maxillectomy defects after surgical reconstruction and/or prosthodontic rehabilitation in an attempt to establish surgical and prosthodontic guidelines that could be organized into a classification system. Forty-seven consecutive patient treatments of palatomaxillary reconstruction at a single facility, The Mount Sinai Medical Center (New York, N.Y.), were reviewed. All patients were rehabilitated with a tissue-borne obturator, a local advancement flap, a fasciocutaneous free flap, or a vascularized bone-containing free flap. Palatomaxillary defects were divided into 3 major classes and 2 subclasses. The aim of this defect-oriented classification system was to organize and define the complex nature of the restorative decision-making process for the maxillectomy patient.

Premaxillary augmentation: adjunct to rhinoplasty

Recession of the premaxillary area is a relatively common deformity. Typically, it presents as a mild weakness of the central maxilla, but in certain instances, such as in the Black and Asian communities, it may be moderate to severe. This condition can be compounded by a narrow nasolabial angle, recessed alar bases, and sunken cheeks. To resolve this deficiency, a new design for premaxillary augmentation is suggested. A bat-shaped premaxillary implant is used for correction. The implant is introduced by means of an intranasal or intraoral approach, while the patient is under either local or general anesthesia. Thirty-three patients have been managed for premaxillary recession and have been corrected by premaxillary augmentation. Satisfactory cosmetic results have been achieved, with only a few minor complications.

Need for evidence-based practice in prosthodontics

STATEMENT OF PROBLEM

Patients, their insurers, the courts, and the scientific community are demanding more evidence to support the effectiveness of health care strategies.

PURPOSE

This article describes evidence-based practice, its origins, and value as a way of addressing the demand for evidence of treatment effectiveness in maxillofacial prosthetics.

MATERIAL AND METHODS

A limited review of maxillofacial prosthetics literature was performed using Medline over the years 1966 to 1998. The retrieved articles were classified by methodologic design and assessed for the strength of their evidence.

RESULTS

Focused and speedy (but not necessarily comprehensive) literature searching methods are available. Critical appraisal skills are available and needed to assess the quality of evidence in support of a treatment and to maintain clinical skills.

CONCLUSION

With appropriate skills and the availability of literature searching hardware and software, evidence-based practice is a powerful means for the practitioner to establish the effectiveness of individual patient treatment, and to prevent the diminution of clinical skills over the course of a career. These skills should be included in training programs.

[Functional complementation of intra- and extra-oral implants. Apropos of a case of extensive loss of substance of the face]

The respective indications for oral or extra-oral implants lead to no confusion: stabilization of dental prostheses for the first, stabilization of maxilo-facial epitheses for the others. We demonstrate that the complementarity of the two types of implants can prove to be very useful in maintaining the maxillary dental prosthesis and the epithesis in a case of severe loss of facial substance affecting particularly the pre-maxilla. This complementary characteristic made it possible to recover fairly rapidly phonation and deglutition, and to remedy somewhat the esthetic damage. In other words to create the essential conditions for a return to everyday life.

Quantification of bone ingrowth into porous block hydroxyapatite in humans

This study sought to quantify bone ingrowth from a single bone-implant surface into porous block hydroxyapatite used in maxillofacial applications. Seventeen maxillary hydroxyapatite implants (implant time of 4-138 months, 39-month mean) were harvested for analysis from 14 patients. The implants had been placed into the lateral maxillary wall during orthognathic surgery, juxtapositioned to the maxillary sinus. Ingrowth was measured in 100-microm increments from a bone-implant interface to a depth of 1500 microm. Bone ingrowth averaged over the 14 patients (0-1100 microm depth) is described by the equation % ingrowth - 20% * (depth in millimeters) + 41.25% (R2 = 0.98, n = 10 incremental depths). Beyond 1100 microm, the average ingrowth remained constant at 15.0 +/- 0.7%. The duration of implantation also showed as affect on the percent ingrowth into the implants at the incremental depths, and the percent ingrowth asymptotically approached a maximum. Overall, the composite average data from all depths is best described by the logarithmic function % ingrowth = 15% * ln(implantation time in months) - 24.0% (R2 = 0.71, n = 14 patients). Several factors may come into play in determining bone ingrowth including the mechanical environment, the osteoconductivity of the implant material, and the osteogenic capability of the tissues in the pore spaces. Measurements of bone ingrowth are most influenced by the depth into the implant and the time the implant was in the body; the age of the patient had little affect on bone ingrowth.

Malar augmentation: a 5-year retrospective review of the silastic midfacial malar implant

OBJECTIVES

To determine the effectiveness and safety of the Silastic midfacial malar implant and to review indications, patient selection, technique, and complications of malar augmentation.

DESIGN

Five-year retrospective review of clinical cases with at least 2-year follow-up.

PATIENTS

A cohort of 60 consecutive private patients with complaints of malar hypoplasia or facial asymmetry.

SETTING

A plastic surgery clinic.

INTERVENTION

Silastic midfacial malar implants were fitted in each patient. Most underwent implantation via the canine fossa approach and in conjunction with another facial plastic procedure.

MAIN OUTCOME MEASURES

Subjective patient satisfaction, photographic grading using a visual analog scale, and complications.

RESULTS

Of the 60 patients, 51 (85.0%) reported an excellent result after at least a 2-year follow-up. Ten patients (16.7%) had some form of undesirable sequelae; however, only 4 (3.4%) of 118 implants had to be revised. Photographically, all 60 patients graded postoperative improvement.

CONCLUSIONS

Findings support the contention that the Silastic midfacial malar implant is a safe and effective alloplastic alternative to treat malar hypoplasia and facial asymmetry. The complication and revision rates are acceptable. Relative technical ease of insertion makes malar augmentation an excellent adjunct for rhytidectomy and rhinoplasty.

Effect of nitinol implant porosity on cranial bone ingrowth and apposition after 6 weeks

The present study addresses two aspects of the use of nitinol in cranial bone defect repair. The first is to verify that there is substantial bone ingrowth into the implant after 6 weeks; the second is to determine the effect of pore size on the ability of bone to grow into the implant during the early (6-week) postoperative period. Porous equiatomic (equal atomic masses of titanium and nickel) nickel-titanium (nitinol) implants with three different morphologies (differing in pore size and percent porosity) were implanted for 6 weeks in the parietal bones of New Zealand White rabbits. Ingrowth of bone into the implants and apposition of bone along the exterior and interior implant surfaces were calculated. The mean pore size (MPS) of implant type #1 (353 +/- 74 microm) differed considerably from implant types #2 (218 +/- 28 microm) and #3 (178 +/- 31 microm). There was no significant difference among implant types in the percentages of bone and void/soft tissue composition of the aggregate implants. The amount of bone ingrowth also was not significantly different among the implant types. Implant #1 was significantly higher in pore volume and thus had a significantly higher volume of ingrown bone (2.59 +/- 0.60 mm3) than implant #3 (1. 52 +/- 0.66 mm3) and a greater amount, but not significantly greater, than implant #2 (1.76 +/- 0.47 mm3). Pore size does not appear to affect bone ingrowth during the cartilaginous period of bone growth in the implant. This implies that within the commonly accepted range of implant porosities (150-400 microm), at 6 weeks bone ingrowth near the interface of nitinol implants is similar.

Facial rehabilitation by the application of osseointegrated craniofacial implants

A new approach to the facial rehabilitation of patients with congenital and acquired deformities is introduced in this short note. This method involves having a bone implant that allows the anaplastologist to fabricate a custom prosthesis for use in patients with disfigurement. The design of the implantation site is done before the surgical procedure. The titanium oxide fixtures and abutments are submerged and extrude through the skin by a small window. The attachment for the replacement part is achieved by using a metallic bar or magnets. A small space is left at the interface for ventilation of the skin and to avoid any maceration that will compromise the integrity and long-term accepted outcome. This new method is not a replacement of the traditional techniques but an augmentation for the accepted methods in facial rehabilitation.

Surgical and prosthetic treatment of congenital absence of the nose: a case report

This paper presents a case of a 5-year old girl with a congenital absence of the nose. Congenital arrhinia is a very rare malformation of the midfacial bones. The difficulties of treating a child with this abnormality are discussed.

Maxillofacial prosthodontics and reconstruction: a Canadian view

A craniofacial osseointegration and maxillofacial prosthetic rehabilitation unit in Edmonton, Canada was visited by the author as part of a higher specialist training programme. The unit has an international reputation as a centre of excellence for the treatment of patients with head and neck abnormalities. The report examines the activities of the unit and how it achieves its 'patient centred' approach to care.

[Is a maxillary prosthesis difficult for patients with trismus?]

Of patients with a postoperative maxillary defect, around 30% are though to have trismus to some extent. In these patients, some difficulty in fabricating a maxillary prosthesis is expected. In this study, 54 patients with trismus were compared with a control group to find some proof of difficulty in making a maxillary prosthetics. Fifty-four of trismus less than 20 mm of a mandibular stroke were experienced out of 185 patients with maxillary prosthetics between October 1984 and October 1992. The trismus was divided into 4 groups of less than 5 mm (1 case), 5 mm-10 mm (10 cases), 11 mm-15 mm (19 cases), and 16 mm-20 mm (24 cases). These case were analyzed by in taking an impression failure, average weight of the prosthesis, time needed to complete the prosthesis and some special form of prosthesis. No apparent differences among the 4 groups or with the control group were found. The cause of the difficulty in making a prosthesis for such patients with trismus are suggested not to be simply due to the range of mouth opening but also to the complexed space formed by the dental defect, alveolar bone defect, spreadability of the lip and the cheek, the mandibular stroke and the so-called scar bundle of the cheek next to the defect.

An algorithm for maxillectomy defect reconstruction

A maxillectomy defect creates a communication from oral cavity to nasal cavity that may extend to the orbit. Functional deglutition and speech problems with a significant soft tissue deficit ensue. This paper defines the reconstruction options for the spectrum of inferior partial maxillectomy defects to midface-orbital exonerations. Treatment protocols from maxillectomy patients treated in January 1991 to February 1996 at a major tertiary care institution were reviewed (n = 108). An ascension of care from dental obturator, nonvascularized graft, local flap, regional flap, and free tissue grafts (n = 28) is described. These data and experience were organized to provide a treatment algorithm to assist in presurgical planning for maxillectomy reconstruction.

The use of percutaneous implants for the prosthetic rehabilitation of orbital defects in irradiated cancer patients: a report of clinical outcomes and complications

This retrospective study evaluated the use of percutaneous craniofacial implants for the prosthetic rehabilitation of patients with a history of orbital exenteration and irradiation for oncologic tumors of the head and neck. A total of 24 implants were placed in six patients. All implants were determined to be osseointegrated at the time of uncovering. Three implants were subsequently resubmerged beneath the soft tissue because of positional interferences with prosthesis fabrication. The remaining 21 implants were ultimately used to retain six orbital prostheses. Two implants failed to maintain osseointegration during the follow-up period and were subsequently removed without complications. This represents an overall integration success rate of 90.5% over a mean follow-up period of 32.8 months (range = 11 to 68 months). The significance of these findings and their relationship to comparable reports in the literature are discussed.

Immediate maxillofacial prosthodontic rehabilitation after radical mid-face tumor resection

Mid-facial surgical defects can adversely affect a patient's esthetics and psychological well-being. Fabrication of a definitive mid-facial prosthesis can be a time-consuming procedure. It is crucial to minimize the time between the tumor resection and initial prosthetic rehabilitation. This article describes a method for rapid fabrication of a transitional facial prosthesis for mid-facial defects.

Lactosorb panel and screws for repair of large orbital floor defects

In a series of five patients with extensive fractures of the orbital floor, we used a biodegradable sheet for bridging of the bony defects. To achieve optimal support of the orbital contents in their anatomically correct position, we fixed the sheet with at least two resorbable screws to the infraorbital rim. This new technique appears to be superior to conventional methods because it offers reproducible results without the need for secondary interventions.

Effects of implant anchorage on midface prostheses

STATEMENT OF PROBLEM

Acquired midface defects may produce functional and psychologic impairments that adversely effects a patient's quality of life. Conventional prostheses may lack adequate retention and stability, diminishing the patient's confidence that the prosthesis will remain in place during routine activities.

PURPOSE

The experience with and patient response to endosseous implants in prosthetic restoration of midface defects is presented in this study.

MATERIAL AND METHODS

Five patients in age from 36 to 88 years were treated with 19 titanium endosseous root-form implants to provide retention and stability for prostheses. Patients responded to a questionnaire rating overall use, effectiveness, and satisfaction of their prosthesis, before and after the use of implants.

RESULTS

All 19 implants were judged to be osseointegrated at abutment connection. Of the 17 implants used prosthetically, 14 (82%) remained osseointegrated and 3 (18%) failed. Analysis of the questionnaire tends to indicate an improvement of the quality of life for the patients with an implant-retained prosthesis.

[The management of extra-oral implants. Anachronisms and paradoxes]

Used in France for ten years and in Sweden since 1977. Extra-Oral Implants (EOI) represent one of the new therapeutic approach of facial defects treatment by maxillo-facial prostheses fixed on implants and of some transmission deafnesses. Audiologic applications are free of charges for the patient but not the prosthetic applications; the authors note this paradox and some other anachronisms. Finally the authors wonder why Extra-Oral implantology is a "correct" science and why Intra-Oral Implantology remains absent from the Administrative texts as if it was a sort of doubtful therapy without scientific principles.

Long-term ingrowth and apposition of porous hydroxylapatite implants

Bone implant materials are often used to fill in bone gaps that frequently result from orthognathic and craniofacial reconstruction. The substrate hydroxylapatite (HA) is commonly implanted into the bone voids, resulting from these conditions due to its established biocompatibility and osteoconductive properties. The porous structure of HA provides a three-dimensional guideline for fibrovascular ingrowth, facilitating the process that ultimately results in the deposition of new bone. Porous HA (Interpore, 200) implants were implanted in the mandible or maxilla of nine humans and removed after 14-30 months (19.1-month mean). There was no evidence of an inflammatory response. The sample composition and apposition against the implant were determined using point counting and a digitizing tablet and software. Percent ingrowth in available space (%IAS) was defined as %Bone/(%Bone + %Void). A new measure of implant saturation (%IAS-%Apposition of bone) was established to help determine the fundamental manner in which long-term HA implants incorporate bone. In the mean, the samples were composed of 27% bone, 21% void, and 53% implant. The apposition percentages averaged 60% bone, 16% void, and 24% soft tissue. The %IAS averaged 58%, and implant saturation averaged -3%, indicating that a near-balance between the implant and surrounding bone has been established.