Stimulation of dental implant osseointegration by low-Intensity pulsed ultrasound: An in vivo preliminary study in a porcine model.

PURPOSE: Several studies have evaluated the interest of Low Intensity Pulsed Ultrasound (LIPUS) in the osseointegration of dental implants in murine or rabbit models. However, the thinness and narrowness bones make it difficult to study the effect of LIPUS. The purpose of this study is to assess the ability of LIPUS to stimulate bone formation in contact with a titanium dental implant in a porcine model. METHODS: Eight adults mini-pigs were used. An implant is placed on each tibial crest in the metaphysis. The right side was treated with LIPUS at 1 MHz and 300 mW/cm2 of acoustic intensity during 15 minutes per day on 5 consecutive days and during 42 days. The left side was not treated. The Bone Volume/Total Volume ratio (BV/TV), the Intersection Surface (IS) of the volume of interest by the binarized bone and the Trabecular bone Thickness (TbTh) around the implant were analyzed. RESULTS: At 42 days, BV/TV ratio is significantly higher on the treated side (42,1+/-8,76% versus 32,31+/-10,11%, p < 0,02); as well as TbTh with 0,13+/-0,01 mm versus 0,10+/-0,01 mm (p < 0,01). IS is also significantly higher on the treated side (40,7 +/- 12,68 mm2 versus 33,68+/-9,44 mm2 at 200 µm from the implant surface; p < 0,01). CONCLUSION: The present study showed that LIPUS can significantly increase bone formation and accelerate the healing process at the bone-implant interface in a porcine model. Its low toxicity, low immunogenicity and non-invasion make it a complementary treatment of choice for improving the bone formation around titanium implants.

[Tooth extraction in irradiated areas]. / Les extractions dentaires en territoire irradié.

Tooth avulsion after head and neck radiotherapy has always been and is still a risk gesture when the avulsion is situated on the irradiation sites. The post-operating effects can become complicated with a delay in healing which can eventually induce an osteoradionecrosis. Dental treatment before the begining of radiotherapy aiming at the elimination of any suspicious tooth, and the generalisation of fluorotherapy aiming at limiting the decayed degeneration, did not make the avulsion indication disappear. At present tooth avulsion is still possible in case of tooth infection or broken tooth.

Guided implant surgery on oral cancer patients: in vitro study.

PURPOSE: Many oral cancer patients (OCPs) are unable to wear conventional prostheses due to the disease and treatment effects, so they are candidates for oral rehabilitation with osseointegrated implants. A guide suitable for OCPs was designed and tested. METHODS: Image-guided systems based on a custom template for oral implant placement are now widespread among healthy patients, but this has not been extended to OCPs. The EasyGuideT system (Keystone Dental, Burlington, MA, USA) for template stabilization is used on healthy edentulous patients, achieved by bone screws, mini-implants or stereolithography with a bone support. All these systems are invasive and cannot be used in many oral cancer patients. We adapted the EasyGuideT to OCP rehabilitation. The first stage focused on developing a template-positioning system for use on edentulous mandibles that is non-invasive, repeatable, stable on the oral mucosa, consistent with the operating room asepsis, and comfortable for the patient. This repositioning system consists of a cube fiducial marker and an extra-oral support using a facial thermoplastic mask. The mask is linked to the surgical template through the cube. The second stage consisted of direct evaluation of the repositioning system reproducibility, performed on 5 adult cadaver skulls. RESULTS: The translation errors and rotation errors obtained using the modified EasyGuideT system were satisfactory in ex vivo experiments on cadaver skulls. CONCLUSION: A non-invasive repositioning system for image-guided implant surgery on oral cancer patients is clinically feasible using a cube fiducial marker and extra-oral support with a facial thermoplastic mask.

[Osteonecrosis of the jaw and bisphophonates in oncology]. / Ostéonécrose des maxillaires et bisphosphonates en cancérologie.

Bisphosphonates are potent osteoclastic inhibitors that are indicated in the prevention of bone complications. They could also be of interest in the prevention of bone metastases. Several recent international publications have highlighted the onset of osteonecrosis of the jaw (ONJ) in patients treated with bisphosphonates. These osteonecroses manifest in the form of bone exposure, recent tooth mobility, swelling and inflammation and, occasionally, localised pain but they can remain asymptomatic for weeks or even months. The prevalence of these osteonecroses in cancer patients treated with bisphosphonates could range from 1 to 10%. In most cases (60 to 80%), ONJ develops after alveolo-dental surgery (e.g. tooth extraction). Length of exposure to bisphosphonate probably increases the risk. Our recommendations regarding the diagnosis, classification, prevention and treatment of cases of ONJ observed during bisphosphonate administration are based on published studies and our experience. It is obvious that the use of bisphosphonates is undoubtedly beneficial in the treatment of bone complications but the incidence of ONJ during long-term treatments and at high doses warrants preventive measures. These measures are straightforward : bucco-dental repair prior to treatment, good hygiene and regular monitoring during treatment. Current, non-invasive procedures are still permitted. In other cases, the suspension of treatment is indicated until healing is complete. The increase in the incidence of ONJs, serious adverse events, raises the issue regarding duration and administration of bisphosphonate treatment in the management of bone metastases. Studies are currently underway in an attempt to answer this issue.

Comparison of the efficacy and safety of miconazole 50-mg mucoadhesive buccal tablets with miconazole 500-mg gel in the treatment of oropharyngeal candidiasis: a prospective, randomized, single-blind, multicenter, comparative, phase III trial in patients treated with radiotherapy for head and neck cancer.

BACKGROUND: Topical antifungal treatments are recommended but rarely used as first-line therapy for oropharyngeal candidiasis (OPC) in patients with cancer. Miconazole Lauriad 50-mg mucoadhesive buccal tablet (MBT) Loramyc reportedly delivered rapid and prolonged, effective concentrations of miconazole in the mouth. The objective of the current study was to compare MBT with miconazole 500-mg oral gel (MOG) in patients with head and neck cancer. METHODS: Two hundred eighty-two patients with head and neck cancer received a 14-day treatment of either single-dose MBT or MOG administered in 4 divided doses. The primary endpoint was clinical success at Day 14, and secondary endpoints included clinical success at Day 7, clinical cure, improvement in clinical symptoms, mycologic cure, recurrence rate, and safety. RESULTS: The success rate was statistically not inferior (P < .0001) in the MBT population to the rate observed in the MOG group (56% vs 49%, respectively; P < .0001). After adjustment for the extent of lesions and salivary secretions, a trend toward superiority was observed in favor of MBT (P = .13), particularly among patients with multiple lesions (P = .013). Results for secondary endpoints were comparable to those observed for the primary endpoint. Compliance with MBT was excellent, and >80% of patients completed treatment. Both treatments were safe. CONCLUSIONS: The success rate of MBT Loramyc was significantly not inferior to that of MOG in the treatment of cancer patients with OPC; and, after adjusting for prognostic variables, it was more effective than MOG. MBT was well tolerated and, thus, may be recommended as first-line treatment in cancer patients who have OPC as an alternative to systemic antifungal agents. Society.