Rehabilitación implanto protésica en paciente con injerto mandibular de larga data / Implant-prosthetic rehabilitation in a patient with a longstanding mandibular graft / Reabilitação protética com implantes em pacientes com enxerto mandibular de longa data

En la actualidad es cada vez más frecuente la consulta de pacientes que siendo sometidos en edades tempranas a cirugías de extirpación tumoral y posterior reconstrucción con injertos presentan problemas tanto funcionales como estéticos, el uso de prótesis implantosoportadas mejora la calidad de vida, pero al mismo tiempo representan un desafío por la baja disponibilidad ósea. Se presenta un caso clínico de rehabilitación protésica implantosoportada en una paciente con gran déficit óseo mandibular como consecuencia de le extirpación de una neoplasia y posterior injerto de costilla. Se colocaron 2 implantes osteointegrados en hueso remanente y rehabilitación con prótesis removible sostenida a una barra colada. Por ser un tratamiento poco invasivo y conservador fue aceptado fácilmente por la paciente y la mejora tanto en la estética como en la función fue notoria.

Nowadays, it is becoming more and more frequent to see patients who underwent surgery for tumor removal and subsequent reconstruction with grafts at an early age, presenting both functional and esthetic problems. The use of implant-supported prostheses improves the quality of life, but at the same time represents a challenge due to the low availability of bone. A clinical case of implant-supported prosthetic rehabilitation is presented in a patient with a great mandibular bone deficit as a consequence of the removal of a neoplasm and subsequent rib graft. Two osseointegrated implants were placed in the remaining bone and rehabilitation with a removable prosthesis supported by a cast bar. Being a minimally invasive and conservative treatment, it was easily accepted by the patient and the improvement in both esthetics and function was notorious.

Atualmente, são cada vez mais frequentes os pacientes submetidos à cirurgia de remoção de tumores e posterior reconstrução com enxertos em idade precoce que apresentam problemas funcionais e estéticos. O uso de próteses implanto-suportadas melhora a qualidade de vida, mas, ao mesmo tempo, representa um desafio devido à baixa disponibilidade de osso. Apresentamos um caso clínico de reabilitação protética implanto-suportada em um paciente com grande déficit ósseo mandibular em consequência da remoção de uma neoplasia e posterior enxerto de costela. Dois implantes osseointegrados foram colocados no osso remanescente e a reabilitação foi feita com uma prótese removível suportada por uma barra de gesso. Por se tratar de um tratamento minimamente invasivo e conservador, foi facilmente aceito pelo paciente e a melhora na estética e na função foi perceptível.

Rehabilitation post maxillary and mandibular reconstruction: Current status and future approaches.

Rehabilitation post reconstruction in head and neck cancer surgery is a vital component to improving quality of life. In this paper we discuss the current approaches to reconstruction of the maxilla and mandible and how they pertain to rehabilitation. There is a detailed discussion of dental rehabilitative challenges with different composite flaps and ways to solve those challenges. We conclude with a discussion about future approaches to reconstruction and how they will impact on improving rehabilitative outcomes and ultimately improve the quality of life of our patients.

Oral rehabilitation of patients after maxillectomy. A systematic review.

Patients who have maxillectomy can be rehabilitated with reconstructive surgery or obturator prostheses with or without osseointegratable implants. To identify studies on possible treatments in this group, we systematically searched the Scopus, Embase, PubMed/Medline, and Cochrane databases to collect data on patients' characteristics, radiotherapy, and results related to speech, swallowing, mastication or diet, chewing, aesthetics, and quality of life. Of the 1376 papers found, six were included, and one other was included after an additional search of references. A total of 252 patients were included, and of them, 86 had reconstructive surgery, 91 were treated with obturator prostheses, 39 had reconstructive surgery or obturator prostheses associated with implants, and 36 had reconstruction plus an obturator prosthesis. Data on radiotherapy were incomplete. There is a lack of consensus about the indication for rehabilitation, as the treatment must be based on the individual characteristics of each patient.

Digitised evaluation of speech intelligibility using vowels in maxillectomy patients.

Among the functional disabilities that patients face following maxillectomy, speech impairment is a major factor influencing quality of life. Proper rehabilitation of speech, which may include prosthodontic and surgical treatments and speech therapy, requires accurate evaluation of speech intelligibility (SI). A simple, less time-consuming yet accurate evaluation is desirable both for maxillectomy patients and the various clinicians providing maxillofacial treatment. This study sought to determine the utility of digital acoustic analysis of vowels for the prediction of SI in maxillectomy patients, based on a comprehensive understanding of speech production in the vocal tract of maxillectomy patients and its perception. Speech samples were collected from 33 male maxillectomy patients (mean age 57.4 years) in two conditions, without and with a maxillofacial prosthesis, and formant data for the vowels /a/,/e/,/i/,/o/, and /u/ were calculated based on linear predictive coding. The frequency range of formant 2 (F2) was determined by differences between the minimum and maximum frequency. An SI test was also conducted to reveal the relationship between SI score and F2 range. Statistical analyses were applied. F2 range and SI score were significantly different between the two conditions without and with a prosthesis (both P < .0001). F2 range was significantly correlated with SI score in both the conditions (Spearman's r = .843, P < .0001; r = .832, P < .0001, respectively). These findings indicate that calculating the F2 range from 5 vowels has clinical utility for the prediction of SI after maxillectomy.

Comparación entre la piezocirugía y los instrumentos rotativos convencionales en la lateralización del nervio dentario inferior / Comparison between the piezosurgery and the conventional rotary surgery in the lateralization of the inferior alveolar nerve

Introducción: la rehabilitación de pacientes desdentados mandibulares posteriores con implantes osteointegrados, se vuelve difícil cuando la cresta alveolar presenta una atrofia severa debido al recorrido superficial del canal mandibular. La lateralización del nervio dentario inferior es una alternativa terapéutica que posibilita la colocación de implantes convencionales y cortos en esta región. Objetivo: comparar la facilidad, efectividad y seguridad de la técnica quirúrgica convencional, realizada con fresas quirúrgicas, y la piezocirugía en la lateralización del nervio dentario inferior. Presentación del caso: paciente con ausencia bilateral de los molares inferiores y cresta alveolar atrófica fue tratada mediante lateralización del nervio dentario inferior y colocación simultánea de implantes. En el lado izquierdo, la lateralización fue realizada con fresas y en el lado derecho, con motor piezoeléctrico. Fue posible observar que la piezocirugía facilitó la técnica quirúrgica, y consecuentemente disminuyó el tiempo operatorio. A la vez, produjo una osteotomía más regular y con menos sangrado, lo cual mejoró la visualización del campo operatorio. Finalmente, el daño neural inmediato fue menor en el lado tratado con motor piezoeléctrico y con recuperación más rápida. Después de 3 meses de seguimiento, los implantes en ambos lados no presentaban pérdida ósea. Conclusiones: el uso del motor piezoeléctrico trajo más beneficios durante la lateralización del nervio dentario inferior, por la simplificación de la técnica quirúrgica y la reducción del sangrado y del daño neural en comparación con el uso de fresas convencionales(AU)

Introduction: the rehabilitation of edentulous posterior mandibular patients with bone-integrated implants becomes difficult when the alveolar crest presents a severe atrophy due to the superficial course of the mandibular canal. The inferior alveolar nerve lateralization is a therapeutic alternative that allows the placement of conventional and short implants in this region. Objective: to compare the easiness, effectiveness, and safety of the conventional surgical technique, performed with surgical drills, and piezosurgery in the lateralization of the inferior alveolar nerve. Case presentation: a patient with bilateral absence of the lower molars and atrophic alveolar crest was treated by lateralization of the inferior alveolar nerve and simultaneous implant placement. On the left side, the lateralization was made with drills and on the right side, with an electric piezotome. It was possible to observe that the piezosurgery facilitated the surgical technique, and consequently decreased the operative time. At the same time, it produced a more regular osteotomy and with less bleeding, which improved the visualization of the operative field. Finally, the immediate neural damage was lower on the side treated with the electric piezotome and with faster recovery. After 3 months of follow-up, the implants on both sides did not show bone loss. Conclusions: the use of the electric piezotome brought more benefits during the lateralization of the inferior alveolar nerve, by the simplification of the surgical technique and the reduction of bleeding and neural damage in comparison with the use of conventional drills(AU)

Implant rehabilitation in fibula-free flap reconstruction: A retrospective study of cases at 1-18 years following surgery.

PURPOSE: To determine the dental implant and prostheses success rate in a cohort of patients who underwent a vascularized fibula-free flap (FFF) for maxillary or mandibular reconstruction. METHODS: The investigators implemented a retrospective cohort study composed of patients who had undergone primary or secondary FFF reconstruction jaw surgery plus placement of 2-6 implants in the reconstructed arch, which were restored with an implant-supported prosthesis. The sample was composed of all patients who underwent FFF surgery between 1998 and 2012 and had either simultaneous or secondary dental implant placement. A total of 28 patients met inclusion criteria. Of these, 22 patients participated in the retrospective review. Patients were examined by an independent observer between January-December 2015. In addition, all patients completed a questionnaire to access satisfaction with the implant-supported prosthesis. RESULTS: The patient cohort consisted of 12 males and 10 females, age 12-70 years. A total of 100 implants were placed, 92 implants in fibular bone and 8 implants in native bone. In the maxilla, 35 implants were placed into fibular bone and 4 into native bone (11 in irradiated patients and 28 in non-irradiated patients). In the mandible, 57 implants were placed into fibular bone and 4 into native bone (15 in irradiated patients and 46 in non-irradiated patients). The mean follow-up after implant loading was 7.8 years (range 1.3-17.5 years). The implant survival rate was 98% (95% CI: 92.2%-99.5%). No statistically significant difference was found in implant success between maxillary and mandibular implants, or between radiated and non-radiated bone. The prostheses success rate, determined by clinical exam and patient satisfaction, was 100%. CONCLUSION: The results of this study suggest that implant survival is high and implant-supported prostheses are a reliable rehabilitation option in patients whose jaws have been reconstruction with a FFF.

Functional Reconstruction of Nonsegmental Mandibular Defect With Fresh Frozen Bone Graft and Delayed Implants Placement.

The loss of teeth and the alveolar bone secondary to resection of mandibular tumors may lead to unfavorable esthetic and functional results with a significant impairment of mastication.The authors report a 53-year-old patient with recurrence of ameloblastoma who was submitted to marginal mandibulectomy. Bone defect was immediately reconstructed using fresh frozen bone graft and 9 months after reconstruction 3 dental implants were inserted in the grafted bone. After 6 months, dental rehabilitation was achieved using a fixed implant-supported prosthesis.The purpose of this clinical report was to show the use of fresh frozen bone graft in the recostruction of mandibular nonsegmental defects.The clinical outcome of bone grafts and dental implants is analyzed retrospectively.

Quadruple zygomatic implants supported rehabilitation in failed maxillary bone reconstruction.

Extreme atrophy of the jaws constitutes a challenge for maxillofacial surgeons. The technique involving Le Fort I osteotomy, bone grafting, and endosseous implants remains the gold standard treatment for class V and class VI atrophy of the maxilla. As severe maxillary atrophy is associated to impaired microvascularization of overlying soft tissues, reconstruction using vascularized free fibula flaps together with endosseous implants is one of the possible treatment plans. When this approach fails, however, retreating these patients using traditional techniques often proves unsatisfactory. This study outlines our clinical experience with full-arch zygoma implant-supported prosthetic rehabilitation to treat severe atrophic maxilla following failure of strategies including multiple Le Fort I procedures or vascularized free fibular flaps.

The Value of SPECT/CT in Monitoring Prefabricated Tissue-Engineered Bone and Orthotopic rhBMP-2 Implants for Mandibular Reconstruction.

Bone tissue engineering shows good prospects for mandibular reconstruction. In recent studies, prefabricated tissue-engineered bone (PTEB) by recombinant human bone morphogenetic proteins (rhBMPs) applied in vivo has found to be an effective alternative for autologous bone grafts. However, the optimal time to transfer PTEB for mandibular reconstruction is still not elucidated. Thus, here in an animal experiment of rhesus monkey, the suitable transferring time for PTEB to reconstruct mandibular defects was evaluated by 99mTc-MDP SPECT/CT, and its value in monitoring orthotopic rhBMP-2 implants for mandibular reconstruction was also evaluated. The result of SPECT/CT showed higher 99mTc-MDP uptake, indicating osteoinductivity, in rhBMP-2 incorporated demineralized freeze-dried bone allograft (DFDBA) and coralline hydroxyapatite (CHA) implants than those without BMP stimulation. 99mTc-MDP uptake of rhBMP-2 implant peaked at 8 weeks following implantation while CT showed the density of these implants increased after 13 weeks' prefabrication. Histology confirmed that mandibular defects were repaired successfully with PTEB or orthotopically rhBMP-2 incorporated CHA implants, in accordance with SPECT/CT findings. Collectively, data shows 99mTc-MDP SPECT/CT is a sensitive and noninvasive tool to monitor osteoinductivity and bone regeneration of PTEB and orthotopic implants. The PTEB achieved peak osteoinductivity and bone density at 8 to 13 weeks following ectopic implantation, which would serve as a recommendable time frame for its transfer to mandibular reconstruction.

Prosthodontic rehabilitation after myofascial flap surgery of hemimaxillectomy defects in the edentulous patient: a clinical report.

OBJECTIVE: The aims of this clinical report were to present and discuss the clinical procedure and the treatment considerations of prosthetic rehabilitation after myofascial flap surgery. DESIGN: A 78-year-old edentulous woman with a squamous cell carcinoma underwent hemimaxillectomy. A temporalis myofascial flap surgery combined with implant-supported prosthesis is one successful approach to the restoration of oral function after hemimaxillectomy. CONCLUSIONS: Although the bulky and mobile nature of a temporalis myofascial flap prevented the retention of a tissue-borne denture, an appropriate impression technique and the fabrication of implant-supported prosthesis using an implant attachment system enhanced the overall satisfaction by the patient.

Stabilising a planning guide in post-mandibulectomy prosthodontic rehabilitation.

Patients presenting with grafted reconstructions of the mandible often lack anatomical features that allow for the consistent placement of a diagnostic denture and planning guide. The mucosa covering the graft appears flat with no discernible ridge form. A method was therefore adapted to provide stability to a guide for the placement of implants. A diagnostic denture was constructed to the try-in stage and duplicated in clear acrylic, with radio-opaque markers placed into potential implant positions. Three mini-implants (Southern implants, Irene, SA) were then placed under local anaesthetic trans-mucosally into the bone graft at positions corresponding to teeth 46, 31 and 36. Access holes were created in the flanges of the diagnostic denture/planning guide to enable it to seat over the mini implant heads and to allow for final positioning. Auto-polymerising resin was then placed to cover each of these heads, thus stabilising the guide. The patient was then referred for a CT scan, to be taken with the planning guide in situ, and a surgical guide was made from the CT data, which also used the mini implants for orientation. At surgery, this ensured the optimal placement of the definitive implants, and the mini-implants could then be removed. This method thus provides enormous beneft to both the planning for, and the placement of, implants into grafted bone in mandibulectomy patients.