Incidence of and Factors Associated with Sinus Membrane Perforation During Maxillary Sinus Augmentation Using the Reamer Drilling Approach: A Double-Center Case Series

Maxillary sinus membrane perforation has been reported as the most common intraoperative complication during sinus augmentation, potentially leading to postoperative infection and consequent loss of graft or even implant failure. Numerous anatomical factors have been demonstrated to affect membrane tearing. However, careful use of proper instrumentation, such as a reamer, seems to play an important role in minimizing the incidence of these complications. Hence, the aim of the present study was to (1) investigate the reliability of reamer drilling for lateral window preparation; (2) examine the incidence of membrane perforation; and (3) study the factors that might influence membrane perforation. Results from this study showed the safety and effectiveness of using a reamer to perform lateral window approach sinus augmentation. The sinus membrane perforation rate was found to be 12.5%. A slightly higher perforation rate was noted in thinner maxillary lateral walls (< 1.25 mm). The authors concluded that reamer drilling is a safe and effective alternate technique for opening the lateral window wall when the lateral wall thickness is ≥ 1.25mm.

Mechanical characteristics of the maxillary sinus Schneiderian membrane ex vivo

OBJECTIVES

It has been speculated that certain Schneiderian membrane thickness (SMT) might be more prone to perforation. This investigation was aimed at studying the mechanical characteristics of the Schneiderian membrane under one- and two-dimensional tests and their correlation to the histological SMT in human samples.

MATERIAL AND METHODS

Sixteen Schneiderian membranes were collected from 11 cadaver heads treated with Thiel's embalming method. The samples were processed and analyzed clinically and histologically. One-dimensional maximum elongation until perforation and two-dimensional resistance to ball penetration were performed after the biopsy. Data was analyzed by using the Wilcoxon rank test and the Spearman's rank correlation.

RESULTS

The histological SMT was 1.36 ± 0.42 mm, whereas the clinical thickness was 0.27 ± 0.21 mm, yielding statistical significance (p = 0.000). The resistance under ball penetration was 0.59 ± 0.43 N and the mean maximum elongation in the one-dimension test 11.19 ± 7.14 mm. Expressed in percentage, the mean stretch was 241.36 ± 227.97% (range 31.5 up to 947%). A weak positive correlation was found between the ball penetration test and the SMT (r = 0.10, p = 0.711), while a weak negative correlation was found between stretching test and the SMT (r = -0.021, p = 0.94).

CONCLUSIONS

Mechanical tests seem to indicate that SMT might not significantly predispose to Schneiderian membrane perforation. Hence, other anatomical and operator's factors should be considered of surpassing importance.

CLINICAL RELEVANCE

Thinner SM might be more prone to perforation when detaching it from the maxillary sinus antrum; however, a thick membrane is not prevented to tear, as their resistance under elastic forces is not higher than thinner ones.

Cellular, Vascular, and Histomorphometric Outcomes of Solvent-Dehydrated vs Freeze-Dried Allogeneic Graft for Maxillary Sinus Augmentation: A Randomized Case Series

PURPOSE

The aim of this study was to compare solvent dehydrated human allograft (SDHA; Puros Allograft) and freeze-dried human allograft (FDHA; MinerOss) in order to determine if the allogeneic bone preservation process influences the amount of remaining particles and newly formed bone in maxillary sinus augmentation.

MATERIALS AND METHODS

Subjects requiring maxillary lateral sinus augmentation with ridge height < 5 mm were included in this study. Maxillary sinuses were randomly assigned to be grafted with a 1:1 ratio of cortical and cancellous bone, either SDHA or FDHA. In both groups, the graft material was mixed with autogenous bone graft at a ratio of 1:1. Morphologic and histomorphometric analyses were completed 6 months after the grafting procedure.

RESULTS

Thirty-four subjects were included in this study. All subjects showed similar demographic characteristics at baseline. Half of the sinuses were grafted with SDHA; the remaining half were grafted with FDHA. Histomorphometric analysis of bone core biopsy samples showed no statistically significant difference between the SDHA or FDHA allogeneic bone substitutes (P = .365), with a mean value of 39.54% ± 0.05% and 31.96% ± 0.08% of mineralized tissue for SDHA and FDHA, respectively. However, a slightly higher mean value of remaining particles was obtained for the FDHA compared with SDHA (18.91% ± 0.09% vs 8.65% ± 0.06%, respectively), although the difference was not statistically significant. Additionally, FDHA demonstrated statistically significantly higher osteoblast, fibroblast, and inflammatory cell numbers.

CONCLUSION

Regardless of the preservation process subtype, allogeneic bone grafting material, in combination with autogenous bone, was demonstrated to be effective for maxillary sinus augmentation bone by means of cellular, vascular, and histomorphometric behavior. Nonetheless, FDHA demonstrated higher cellularity compared to SDHA, suggesting accelerated turnover activity for the latter grafting material.

Functional reconstruction after subtotal glossectomy in the surgical treatment of an uncommon and aggressive neoplasm in this location: Primary malignant melanoma in the base of the tongue

Primary malignant melanoma of the oral cavity is a rare neoplasm, especially on the tongue. We report a case of mucosal melanoma at the base of the tongue, an extremely rare location (only about 30 cases have been reported in literature). The extension study doesn´t revealed distant metastatic lesions. The patient was treated by subtotal glossectomy and bilateral functional neck dissection. Tongue is one of the most difficult structures to reconstruct, because of their central role in phonation, swallowing and airway protection. The defect was reconstructed with anterolateral thigh free flap. Surgical treatment was supplemented with adjuvant immunotherapy. The post-operative period was uneventful. At present, 24 months after surgery, patient is asymptomatic, there isn´t evidence of recurrence of melanoma and he hasn´t any difficulty in swallowing or phonation.

Key words:Malignant mucosal melanoma, anterolateral thigh free flap, phonation, swallowing.

Temporomandibular joint arthrocentesis. Review of the literature

The treatment of the temporomandibular joint (TMJ) is still controversial. TMJ arthrocentesis represents a form of minimally invasive surgical treatment in patients suffering from internal derangement of the TMJ, especially closed lock. It consists of washing the joint with the possibility of depositing a drug or other therapeutic substance. Resolution of symptoms is due to the removal of chemical inflammatory mediators and changes in intra-articular pressure. Numerous clinical studies regarding this technique have been published. The goal of this paper is to review all clinical articles that have been published with regard to the critique of this technique. 19 articles with different designs fulfilling selection guidelines were chosen. A series of clinical and procedure variables were analyzed. Although the mean of improvement was higher that 80%, further research is needed to determine more homogeneous indications for TMJ athrocentesis.

Giant cell granuloma of the maxilla. Global management, review of literature and case report

Giant cell granuloma is a relatively rare benign entity but can be locally aggressive. Histologically characterized by intense proliferation of multinucleated giant cells and fibroblasts. Affects bone supported tissues. Definitive diagnosis is given by biopsy. Clinically manifest as a mass or nodule of reddish color and fleshy, occasionally ulcerated surface. They can range from asymptomatic to destructive lesions that grow quickly. It is a lesion to be considered in the differential diagnosis of osteolytic lesions affecting the maxilla or jaw. Its management passed from conservative treatment with intralesional infiltration of corticosteroids, calcitonin or interferon, to the surgical resection and reconstruction, for example with microvascular free flaps.

Key words:Giant cell granuloma, intralesional injection, microvascular free flap, fibula.

Schwannoma of tongue

The schwannomas are nervous tissue tumors. We report a case of schwannoma of oral tongue. Because schwannomas are quite rare in the oral cavity, they are often not immediately included in the differential diagnosis of oropharyngeal masses, causing delay in identification and treatment. The definitive diagnosis requires histopathologic examination.

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.