An In Vitro Model to Evaluate the Accuracy of Guided Implant Placement Based on the Surgeon's Experience.

PURPOSE: To evaluate whether there are differences in the accuracy of guided implant placement based on the surgeon's experience level. MATERIALS AND METHODS: Fifteen surgeons, divided into three groups based on experience level (group I, expert; group II, intermediate; group III, novice), placed six implants in five identical mandibles (75 mandibles and 450 implants). A planning and stereolithographic guide was generated using cone beam computed tomography (CBCT) images and implant planning software (Nemoscan, Nemotec) and was used in all cases. After the implants were placed in each mandible, another scan was taken, and the three-dimensional (3D) images of each scan were blended with the images in the planning guide to evaluate any deviations. Any differences in platform and apex position and the angle of the implant were measured. The differences between each surgeon and each group were compared using multivariate analysis of variance (MANOVA). RESULTS: There were significant differences in the implant angles among the three groups (P = .001). Group III (novices) presented the greatest angle deviation and showed more deviations than group I (experts) (P = .024) and group II (intermediate) (P = .001) did. There were no significant differences between groups I and II (P = .368). There were no significant differences among the groups in terms of platform (P = .135) and apex position (P = .092). CONCLUSION: Some degree of deviation can occur between the planned placement of the implant and its definitive placement, and this deviation may be influenced by the surgeon's experience. Expert surgeons show less angle deviation than novice surgeons. Although these differences (less than 0.5 degrees) are statistically significant, they may be considered clinically irrelevant.

Complication rate in 200 consecutive sinus lift procedures: guidelines for prevention and treatment.

PURPOSE: Maxillary sinus grafting is a predictable and reliable procedure that has been routinely performed for more than 30 years. The complication rate is low, but some cases may require additional surgery, and the outcome of oral rehabilitation may be affected. The purpose of the present study was to evaluate the early and late complications after sinus lift procedures performed in the authors' center, with special attention to risk factors and their connection to the principles of prevention and treatment. MATERIALS AND METHODS: A retrospective analysis of 127 patients was performed. During an 8-year period, patients underwent preprosthetic surgery with implants and a maxillary sinus lift procedure because of maxillary atrophy. In total, 202 sinus lift procedures were performed and 364 implants were placed (117 simultaneously and 247 delayed). Clinical data, local or systemic disease, risk factors, type of surgery, intraoperative and postoperative complications, and the evolution of the implant zone were recorded. RESULTS: The most common intraoperative complication was damage to the Schneiderian membrane (25.7%), which did not show any connection to postoperative complications. Thirty patients (14.9%) developed postoperative complications, including wound infection, abscess, or dehiscence with drainage (9 cases), maxillary sinusitis of the operated area (6 cases), partial exposure of the simultaneous onlay graft (6 cases), and loss of the graft (2 cases). CONCLUSION: Sinus lift surgery is a proven and reliable technique because of the low observed rate of postoperative complications and the success rate of implants placed into the grafted area. To minimize risk, care must be taken with all technical details and risk factors that can lead to fatality.

Costochondral graft with green-stick fracture used in reconstruction of the mandibular condyle: experience in 13 clinical cases.

Since its publication in 1920 by Gillies, costochondral grafts have been used by surgeons to replace and injured mandibular condyle and to reconstruct the temporomandibular joint. This procedure is currently applied in cases of congenital dysplasia, developmental defects, temporomandibular ankylosis, neoplastic disease, osteoarthritis and post-traumatic dysfunction. Over the years, various procedures for the reconstruction with this type of graft have been described. In 1989, Mosby and Hiatt described a technique for setting the graft securely, reducing the space between the graft and the mandibular area. In 1998, Monje and Martín-Granizo developed a variation of this method, enabling a precise adaptation of the costochondral graft to the remaining mandibular ramus. The aim of this study is to evaluate the functional and anatomic results of the costochondral graft treatment by green-stick fracture for reconstruction of the TMJ in the 10 years following the description of this technique. We carry out a retrospective study of thirteen cases of temporomandibular pathology (tumors, ankylosis and hypoplasia) treated during a period of ten years from 1998 to 2008. In all these cases, the technique described by Monje and Martín-Granizo was used: removal of the sixth rib, fixation to a titanium mini-plate using screws, making an internal corticotomy in order to obtain a green-stick fracture of the outer cortex, providing adequate adaptation of the graft to the mandibular ramus. The graft was then set in place, attaching it with titanium screws. This technique was successful in achieving optimal ossification, a good interincisal opening and satisfactory cosmetic results. In conclusion, according to our experience, the green-stick fracture for the adaptation of costochondral grafts to the remaining mandibular ramus has presented outstanding results in the surgical treatment of temporomandibular pathology.

Metastasis of renal clear-cell carcinoma to the oral mucosa, an atypical location.

The majority of cases of metastatic tumors involve the mandible and some the maxilla but they are considerably less common in intraoral soft tissues. In addition, the primary tumor is known in the majority of cases; although in one-third of such cases, metastasis is the first clinical manifestation. The most common primary tumors metastasizing to the mouth are lung carcinoma in men and breast carcinoma in women. An oral metastasis implies a serious prognosis, as in the majority of patients there is multiple organ involvement at the time of diagnosis. We present the case of a 52-year old patient with renal pathology who came to the emergency room due to a rapidly increasing gingival tumor. With the provisional clinical diagnosis of a pyogenic granuloma,the tumor was excised. Subsequent anatomopathological analysis revealed a tumor metastasis compatible with clear-cell carcinoma, and its renal origin was confirmed by means of immunohistochemical techniques.

Efecto inhibitorio de bauhinia variegata L. sobre la glucación no enzimática de la hemoglobina / Inhibitory effect of bauhinia variegata L. on hemoglobin nonenzymatic glycation

Una decocción de las hojas de Bauhinia variegata L. es ampliamente utilizada en la medicina tradicional Venezolana como antidiabética. La decocción de las hojas de esta especie demostró un significativo efecto inhibitorio in vitro sobre la glucación no enzimática de la hemoglobina. Los resultados sugieren un potencial antidiabético de Bauhinia variegata L. para la prevención de las complicaciones diabéticas