Ameloblastic carcinoma of the maxilla: A case report

This study aims to present the clinical features and treatment of a case of maxillary ameloblastic carcinoma. A meloblastic carcinoma is a rare malignant odontogenic carcinoma that has metastatic potential. Due to its rare incidence, there are few studies focusing on its radiological characteristics. When ameloblastic carcinoma demonstrates an aggressive appearance, it may be diagnosed as a malignant tumor; however, in cases showing a non-aggressive appearance, it is difficult to distinguish ameloblastic carcinoma from ameloblastoma. We report a case of ameloblastic carcinoma of the maxilla in a 59-year-old male patient, including the clinical signs, radiological images and pathological features. A partial area was surgically excised under local anesthesia and the material was sent to the Laboratory of Oral Pathology. The histological sections revealed a fragmented odontogenic tumor of epithelial origin, consisting of solid parenchyma and also revealed basal cells resembling ameloblasts, occasionally arranged in palisades. Certain parts of the architecture resembled that of an ameloblastoma; however, the cytology of other areas confirmed the diagnosis of ameloblastic carcinoma of the maxilla. The patient was scheduled for definitive surgery, including a right maxillectomy and radiotherapy. The patient was followed up every 3 months. After 2 years follow-up, there were no clinical or radiological signs of recurrence.

Resultados da expansão de maxila cirurgicamente assistida sem disjunção ptérigomaxilar: uma avaliação tridimensional

A expansão rápida da maxila cirurgicamente assistida tornou-se amplamente utilizada e muito aceitável no tratamento da deficiência maxilar de pacientes adolescentes e adultos. Diversas técnicas cirúrgicas foram propostas ao longo dos anos com o objetivo de solucionar este problema de forma eficiente, com estabilidade dos resultados e baixa morbidade. Controvérsias em relação ao procedimento cirúrgico persistem, principalmente relacionadas a quais osteotomias devem ser realizadas para se obter bons resultados. O objetivo deste trabalho foi avaliar os resultados da expansão ortocirúrgica da maxila realizando osteotomias nas paredes laterais da maxila e na sutura palatina mediana. Foram selecionados dezessete pacientes adultos portadores de deficiência transversa maxilar, com média de idade de 24 anos e 8 meses; todos foram submetidos a exames de tomografia computadorizada convencional e moldagens maxilares previamente ao procedimento cirúrgico e após três meses, no mínimo, do término de ativação e estabilização do aparelho expansor. As medidas do pós-cirúrgico foram confrontadas com as do pré-cirúrgico e os resultados foram comparados e analisados estatisticamente. Foi obtida a expansão desejada clinicamente em todos os pacientes. No entanto, a quantidade de expansão na região de molares foi estatisticamente maior nas áreas referentes aos dentes, enquanto que os resultados obtidos referentes aos caninos se mostraram similares nas três regiões maxilares avaliadas. Quando comparadas às regiões de caninos e molares entre si, a expansão intercaninos foi maior na altura dos forames palatinos e o inverso ocorreu nas regiões de processo alveolar e dentária, nas quais a expansão intermolar foi maior.

Is flapless implant surgery a viable option in posterior maxilla? : a review

This article reviews the literature on the outcome of flapless surgery for dental implants in the posterior maxilla. The literature search was carried out in using the keywords: flapless, dental implants and maxilla. A hand search and Medline search were carried out on studies published between 1971 and 2011. The authors included research involving a minimum of 15 dental implants with a followup period of 1 year, an outcome measurement of implant survival, but excluded studies involving multiple simultaneous interventions, and studies with missing data. The Cochrane approach for cohort studies and Oxford Centre for Evidence- Based Medicine were applied. Of the 56 published papers selected, 14 papers on the flapless technique showed high overall implant survival rates. The prospective studies yielded 97.01% (95% CI: 90.72–99.0) while retrospective studies or case series illustrated 95.08% (95% CI: 91.0–97.93) survival. The average of intraoperative complications was 6.55% using the flapless procedure. The limited data obtained showed that flapless surgery in posterior maxilla areas could be a viable and predictable treatment method for implant placement. Flapless surgery tends to be more applicable in this area of the mouth. Further long-term clinical controlled studies are needed.

Characteristics and dimensions of the Schneiderian membrane: a radiographic analysis using cone beam computed tomography in patients referred for dental implant surgery in the posterior maxilla

To determine the dimensions of the Schneiderian membrane using limited cone beam computed tomography (CBCT) in individuals referred for dental implant surgery, and to determine factors influencing the mucosal thickness.

Flapless dental implant surgery : a retrospective study of 1,241 consecutive implants

Purpose: The purpose of this study was to identify retrospectively the predictors of implant survival when the flapless protocol was used in two private dental practices. Materials and Methods: The collected data were initially computer searched to identify the patients; later, a hand search of patient records was carried out to identify all flapless implants consecutively inserted over the last 10 years. The demographic information gathered on statistical predictors included age, sex, periodontal and peri-implantitis status, smoking, details of implants inserted, implant locations, placement time after extraction, use of simultaneous guided hard and soft tissue regeneration procedures, loading protocols, type of prosthesis, and treatment outcomes (implant survival and complications). Excluded were any implants that required flaps or simultaneous guided hard and soft tissue regeneration procedures, and implants narrower than 3.25 mm. Results: A total of 1,241 implants had been placed in 472 patients. Life table analysis indicated cumulative 5-year and 10-year implant survival rates of 97.9% and 96.5%, respectively. Most of the failed implants occurred in the posterior maxilla (54%) in type 4 bone (74.0%), and 55.0% of failed implants had been placed in smokers. Conclusion: Flapless dental implant surgery can yield an implant survival rate comparable to that reported in other studies using traditional flap techniques.

An evaluation of clinical procedures used in dental implant treatment in posterior maxilla using flapless technique

This study was a measure forward in cultivating the scientific basis for an approach to examine clinical procedure in Flapless dental implant surgery. The thesis is based on: the systematic review, retrospective study of flapless implants, and in vivo study on the osseo-integration in osteoporotic rats. Dr Doan investigated "clinical procedures used in dental implant treatment in posterior maxilla using flapless technique". The work has yielded significant contributions to the area of implant flapless surgery and its effects on osteoporotic patients having implants in the posterior maxilla.

Histomorphometric Evaluation of Bioceramic Molecular Impregnated and Dual Acid-Etched Implant Surfaces in the Human Posterior Maxilla

Background: Physical and bioceramic incorporation surface treatments at the nanometer scale showed higher means of bone-to-implant contact (BIC) and torque values compared with surface topography at the micrometer scale; however, the literature concerning the effect of nanometer scale parameters is sparse. Purpose: The aim of this study was to evaluate the influence of two different implant surfaces on the percentage bone-to-implant contact (BIC%) and bone osteocyte density in the human posterior maxilla after 2 months of unloaded healing. Materials and Methods: The implants utilized presented dual acid-etched (DAE) surface and a bioceramic molecular impregnated treatment (Ossean(R), Intra-Lock International, Boca Raton, FL, USA) serving as control and test, respectively. Ten subjects (59 1 9 years of age) received two implants (one of each surface) during conventional implant surgery in the posterior maxilla. After the non-loaded period of 2 months, the implants and the surrounding tissue were removed by means of a trephine and were non-decalcified processed for ground sectioning and analysis of BIC%, bone density in threaded area (BA%), and osteocyte index (Oi). Results: Two DAE implants were found to be clinically unstable at time of retrieval. Histometric evaluation showed significantly higher BIC% and Oi for the test compared to the control surface (p < .05), and that BA% was not significantly different between groups. Wilcoxon matched pairs test was used to compare the differences of histomorphometric variables between implant surfaces. The significance test was conducted at a 5% level of significance. Conclusion: The histological data suggest that the bioceramic molecular impregnated surface-treated implants positively modulated bone healing at early implantation times compared to the DAE surface.

Rehabilitation of Atrophic Maxilla Using the Combination of Autogenous and Allogeneic Bone Grafts Followed by Protocol-Type Prosthesis

Currently, there are several techniques for the rehabilitation of atrophic maxillary ridges in literature. The grafting procedure using autogenous bone is considered ideal by many researchers, as it shows osteogenic capability and causes no antigenic reaction. However, this type of bone graft has some shortcomings, mainly the restricted availability of donor sites. In recent years, several alternatives have been investigated to supply the disadvantages of autogenous bone grafts. In such studies, allogeneic bone grafts, which are obtained from individuals with different genetic load, but from the same species, have been extensively used. They can be indicated in cases of arthroplasty, surgical knee reconstruction, large bone defects, and in oral and maxillofacial reconstruction. Besides showing great applicability and biocompatibility, this type of bone is available in unlimited quantities. on the other hand, allogeneic bone may have the disadvantage of transmitting infectious diseases. Atrophic maxillae can be treated with bone grafts followed by osseointegrated implants to obtain aesthetic and functional oral rehabilitation. This study aimed to show the viability of allogeneic bone grafting in an atrophic maxilla, followed by oral rehabilitation with dental implant and protocol-type prosthesis within a 3-year follow-up period by means of a clinical case report.

Use of 4 Immediately Loaded Zygomatic Fixtures for Retreatment of Atrophic Edentulous Maxilla After Complications of Maxillary Reconstruction

This article reports the 20-month clinical outcome of the use of 4 zygomatic implants with immediate occlusal loading and reverse planning for the retreatment of atrophic edentulous maxilla after failed rehabilitation with autogenous bone graft reconstruction and maxillary implants. The intraoral clinical examination revealed mispositioned and loosened implants underneath a maxillary complete denture. The panoramic radiograph showed 6 maxillary implants. One implant was displaced into the right maxillary sinus, and the implant anchored in the region of tooth 21 was fractured. The other implants presented peri-implant bone loss. The implants anchored in the regions of teeth 21 to 23 and 11 to 13 were first removed. After 2 months, the reverse planning started with placement of 4 zygomatic fixtures, removal of the implants migrated into the sinus cavity and anchored in the region of tooth 17, and installation of a fixed denture. After 20 months of follow-up, no painful symptoms, peri-implant inflammation or infection, implant instability, or bone resorption was observed. The outcomes of this case confirm that the zygoma can offer a predictable anchorage and support function for a fixed denture in severely resorbed maxillae.

Conservative Management of a Large Keratocystic Odontogenic Tumor in the Maxilla

Keratocystic odontogenic tumor is characterized by high recurrence rates. Conservative or aggressive management has been suggested as a method of treatment. Decompression is a conservative treatment that has been used in the treatment of large odontogenic cysts. The authors report a case of a 14-year-old patient with a keratocystic odontogenic tumor located in the right maxilla, which was treated by decompression followed by enucleation with curettage. The lesion did not recur on follow-up for 3 years after the enucleation surgery.

B-cell lymphoblastic lymphoma in the maxilla of a child: A rare case report

Lymphoblastic lymphoma is a malignant neoplasia that originates from B or T lymphocyte precursors and rarely occurs in the mouth. The authors report a rare case of B-cell lymphoblastic lymphoma in the maxilla of a child. Clinical examination revealed facial asymmetry with a swelling of the right maxilla, covered by healthy mucosa and painful to palpation. Radiographic examination revealed a poorly defined radiolucent lesion. Based on the hypothesis of malignant neoplasia of hematopoietic origin, an incisional biopsy was performed. Histological examination revealed malignant neoplasia with proliferation of monomorphic, lymphoid cells. Immunohistochemical staining was positive for leucocyte common antigen (LCA), CD 10, CD20, CD79, and terminal deoxynucleotidyl transferase (TdT). After the diagnosis of B-cell lymphoblastic lymphoma, the patient underwent chemotherapy, but died of leukoencephalopathy and demyelinization caused by high doses of methotrexate.

Postsurgical stability of oropharyngeal airway changes following counter-clockwise maxillo-mandibular advancement surgery

Purpose: This study evaluated oropharyngeal airway changes and stability following surgical counter-clockwise rotation and advancement of the maxillo-mandibular complex.Methods and Patients: Fifty-six adults (48 females, 8 males), between 15 and 51 years of age, were treated with Le Fort I osteotomies and bilateral mandibular ramus sagittal split osteotomies to advance the maxillo-mandibular complex with a counter-clockwise rotation. The average postsurgical follow-up was 34 months. Each patient's lateral cephalograms were traced, digitized twice, and averaged to estimate Surgical changes (T2-T1) and Postsurgical changes (T3-T2).Results: During surgery, the occlusal plane angle decreased significantly (8.6 +/- 5.8 degrees) and the maxillo-mandibular complex advanced and rotated counter-clock-wise. The maxilla moved forward (2.4 +/- 2.7 mm) at ANS and the mandible was advanced 13.1 +/- 5.1 min at menton, 10 +/- 4.4 mm at point B, and 6.9 +/- 3.7 mm at lower incisor edge. Postsurgical hard tissue changes were not statistically significant. While the upper oropharyngeal airway decreased significantly (4.2 +/- 3.4 min) immediately after surgery, the narrowest retropalatal, lowest retropalatal airway, and the narrowest retroglossal airway measurements increased 2.9 +/- 2.7, 3.7 +/- 3.2, and 4.4 +/- 4.4 mm, respectively. Over the average 34 months Postsurgical period, upper retropalatal airway increased 3.9 +/- 3.7 mm, while narrowest retropalatal, lowest retropalatal airway, and narrowest retroglossal airway remained stable. Head posture showed flexure immediately after Surgery (4.8 +/- 5.9 degrees) and extension postsurgically (1.6 +/- 5.6 degrees).Conclusion: Maxillo-mandibular advancement with counter-clockwise rotation produces immediate increases in middle and lower oropharyngeal airway dimensions, which were constrained by changes in head posture but remain stable over the postsurgical period. The upper oropharyngeal airway space increased only on the longest follow-up. (C) 2006 American Association of Oral and Maxillofacial Surgeons.

All-on-four concept and immediate loading for simultaneous rehabilitation of the atrophic maxilla and mandible with conventional and zygomatic implants

We report the simultaneous rehabilitation of an edentulous patient with a hybrid (zygomatic and conventional implants) all-on-four implant-supported prosthesis for the maxilla and a standard (conventional implants) all-on-four implant-supported prosthesis for the mandible. The transfer impression was made with a multifunctional guide and the upper and lower prostheses were placed 24 h postoperatively. Clinical and radiographic examinations showed no infection or bony resorption 2 years later. Simultaneous maxillary and mandibular rehabilitation with all-on-four immediate loading is a viable, fast and effective option for edentulous patients. (C) 2009 Published by Elsevier Ltd on behalf of The British Association of Oral and Maxillofacial Surgeons.