Can CT predict the development of oroantral fistula in patients undergoing maxillary third molar removal?

PURPOSE: In maxillary wisdom tooth extraction, the necessity of CT is unknown. The purpose of this study was to investigate whether CT adding to orthopantomography is useful for predicting oroantral perforation during maxillary third molar extraction. METHODS: Various risk factors for oroantral perforation during maxillary third molar extraction were investigated by univariate and multivariate analyses. We analyzed those of all patients and the patients who underwent CT, respectively. The proximity of the roots to the maxillary sinus floor (root-sinus [RS] classification) and Archer classification were assessed using panoramic radiography. The number of roots and vertical relationship were assessed using CT. RESULTS: A total of 604 out of 3299 patients underwent CT adding to orthopantomography. In all cases, multivariate analyses except for CT findings showed that the RS classification type III/IV and the Archer classification Type B/C/D in panoramic findings were significantly correlated with oroantral perforation as radiological findings. In cases for which CT was performed, multivariate analyses showed that one root (OR 12.87) and the vertical relationship Type D (OR 5.63) in CT findings, besides the RS classification type III/IV (OR 4.47) in panoramic findings, were significantly related to oroantral perforation. CONCLUSION: The RS classification and the Archer classification in panoramic findings can predict the risk of oroantral perforation. The usefulness of CT adding to orthopantomography is limited. However, when the relationship between the upper wisdom tooth and maxillary sinus floor (RS classification) is unclear, to check whether the number of roots is one and the apex of one root is projecting into the maxillary sinus in CT findings, is useful for the prediction.

A Retrospective Evaluation of Partial Glossectomy for Early Tongue Cancer Using a Carbon Dioxide Laser.

OBJECTIVE: The purpose of this study was to retrospectively evaluate the postoperative results of partial glossectomy for early tongue cancer using a carbon dioxide laser (CO2 laser). BACKGROUND DATA: CO2 lasers are frequently used for the excision or treatment of soft tissue in a range of diseases, including oral cancer, leukoplakia, mucocele, anomalies of the labial and lingual frenum, and peri-implantitis. MATERIALS AND METHODS: We retrospectively reviewed 31 primary cases of early superficial tongue cancer that were treated using CO2 lasers. In this study, early superficial cancer of the tongue is defined as a T1 or T2 tumor (TNM classification, NOMO; type, superficial spread, or exophytic; depth, <5 mm). The lesions were stained with 10% Lugol's solution and excised with a 5- or 10-mm safety margin from the nonstained area or induration using a CO2 laser. The raw surface was covered with a polyglycolic acid sheet using fibrin glue spray (n = 23), sutures (n = 6), or both (n = 2). Five of the patients showed a bleeding tendency: 1 was taking warfarin 100 mg per day, 1 was taking 350 mg per day, 2 were taking aspirin 100 mg per day, and 1 was taking aspirin 200 mg per day. RESULTS: There were no cases of postoperative bleeding. Regarding postoperative pain, all patients could stop taking analgesic drugs by 1 month after undergoing the operation. In regards to postoperative difficulty to swallow, all could start swallowing rice gruel 2 days after the operation. The surgical margin was unclear in two cases due to the thermal denaturation of the excisional margin. The 2-year local control rate was 100% and subsequent cervical lymph node metastasis rate was 6.5%. CONCLUSIONS: In terms of recurrence, metastasis, postoperative bleeding, postoperative pain, and swallowing, partial glossectomy for early tongue cancer using a CO2 laser might therefore help improve the postoperative course.

Efficacy of pimobendan on survival and reoccurrence of pulmonary edema in canine congestive heart failure.

The aim of this study was to evaluate the efficacy of pimobendan with conventional therapies on survival and reocurrence of pulmonary edema in dogs with congestive heart failure (CHF) caused by myxomatous mitral valve disease (MMVD). Records of 197 client-owned dogs from 14 veterinary hospitals were included in this study. Dogs were administered conventional treatments with or without pimobendan. Sixty-four dogs received a standard dose of pimobendan (0.20-0.48 mg/kg every 12 hr (q12hr)), 49 dogs received a low dose of pimobendan (0.05-0.19 mg/kg q12hr), and 84 dogs received conventional therapy alone. Dogs in the standard-dose and low-dose pimobendan groups had significantly longer median survival times than dogs in the conventional group (334, 277 and 136 days, respectively; P<0.001). The reoccurrence rate of pulmonary edema in the standard-dose group was significantly lower than in the low-dose and conventional groups (43%, 59% and 62%, respectively; P<0.05). Combination of pimobendan with a conventional treatment regimen significantly prolonged survival time after an initial episode of pulmonary edema in dogs with CHF caused by MMVD. There was no difference in survival between dogs administered standard and low doses of pimobendan, but pimobendan did prevent the reoccurrence of pulmonary edema in a dose-dependent manner.

Effectiveness of photocoagulation using an Nd:YAG laser for the treatment of vascular malformations in the oral region.

OBJECTIVE: The purpose of this study is to make a clinical evaluation of vascular malformations in the oral region treated by photocoagulation with an Nd:YAG laser, to determine its effectiveness. BACKGROUND DATA: The Nd:YAG laser, with a wavelength of 1064 nm in the near-infrared part of the electromagnetic spectrum, has unique characteristics, such as absorption by oxygenated hemoglobin, negligible absorption by water, and a deep depth of penetration, all of which are ideal for performing the photocoagulation of vascular malformations. METHODS: The subjects were 67 patients (69 cases) with vascular malformations in the oral region who visited our hospital from 2004 to 2011, and were treated by photocoagulation using an Nd:YAG laser. They consisted of 23 male patients and 44 female patients, ranging from 7 to 89 years of age. Lesion size was classified for convenience into two groups (<15 mm or ≥ 15 mm) for clinical analysis and evaluation. The lesions were located at sites including the lip, tongue, buccal mucosa, gingiva, mouth floor, and soft palate, and ranged in size from 3 to 42 mm along the major axis. Fifty patients (74.6%) were treated on an outpatient basis, whereas 17 patients (25.4%) were treated in the hospital. All patients were treated using an Nd:YAG laser at an output of 8-15 W under local anesthesia. RESULTS: No patient developed serious complications from this treatment. However, it was necessary to irradiate the laser beam two or more times in cases of deep-seated lesions. CONCLUSIONS: We were able to obtain satisfactory results without clinical complications, using only external irradiation. These results suggest that the Nd:YAG laser is effective for the treatment of vascular malformations in the oral region.

Clinical evaluation of application of polyglycolic acid sheet and fibrin glue spray for partial glossectomy.

PURPOSE: The aim of this study was to evaluate the usefulness of covering open wounds with a polyglycolic acid (PGA) sheet and a fibrin glue spray after partial glossectomy. MATERIALS AND METHODS: We clinically evaluated postoperative pain and scar contracture in 44 patients who underwent partial glossectomy followed by covering with a PGA sheet and a fibrin glue spray (PGA sheet group), as compared with 29 patients who were closed primarily (primary closure group). RESULTS: Duration of nonsteroidal anti-inflammatory drugs was almost the same between the PGA sheet group and the primary closure group. The degree of scar contracture was mild in many cases in both groups. In the case in which the excision area was wide and depth was shallow, there was a tendency for the scar contracture to be less in the PGA sheet group. CONCLUSIONS: Our findings showed that the use of a PGA sheet and fibrin glue spray for open wounds resulting from partial glossectomy was useful in terms of rapid relief from postoperative pain and prevention of scar contracture.

Prevention of lingual inclination of the transport segment in vertical distraction osteogenesis in the mandible.

Vertical distraction osteogenesis can extend not only to hard tissues but also to soft tissues. There is a tendency to cause progressive lingual inclination of the distracted segment. This study describes a method for preventing the lingual inclination of the transport segment in patients with vertical distraction osteogenesis in the anterior region of the mandible and reports the results of long-term follow-up. The subjects included 5 patients who had severely atrophic ridges in the anterior mandible. In all cases, a part of the mental protuberance was scraped out, and the distractor was placed suitably in a labioinclination beforehand. Therefore, the transport segments did not lean to the lingual side and had long-term stability.

Analysis of the 619 Brånemark System TiUnite implants: a retrospective study.

The purpose of this retrospective study was to determine the outcome of Brånemark System TiUnite® implants (Nobel Biocare/Sweden), and to identify the risk factors associated with implant failure. A total of 151 patients (83 maxillae and 91 mandibles) received 619 implants from July 2003 until May 2010. The patients included 86 males and 65 females, with a median age of 51.6 years and an age range of 16 to 90 years at the time of implant surgery. Seventeen maxillae and 16 mandibles were completely edentulous, and 66 maxillae and 75 mandibles were partially edentulous. All the patients were followed until June 2011. Among the 619 implants, 9 maxillary implants and 8 mandibular implants were unsuccessful. The overall survival rate was 96.82%. A logistic regression analysis identified that a history of steroid treatment, application of a dento-maxillary prosthesis, a lack of mechanical coupling between the implants, and the length of the implants (≤8.5mm) were significant predictors of implant failure.

Maxillary sinus floor elevation combined with a vertical onlay graft.

We performed maxillary sinus floor elevation combined with a vertical onlay graft for a total of 11 sides of nine patients (1 woman and 8 men) in our Hospital. On CT, the preoperative minimum alveolar bone thickness with a mean of 1.8 mm was improved to 15.3 mm within a month after this surgery. A total of 20 dental implants were placed and there was only one failed implant. With the average follow-up of 15.6 months, an average of 3.4 mm of bone absorption was found in the site of the maxillary sinus and 1.1 mm in the site of the onlay graft. The crown-implant ratio in all cases was within the permissible range. Consequently, this bone augmentation surgery was considered to be useful.

Analysis of 472 Brånemark system TiUnite implants:a retrospective study.

PURPOSE: The purpose of this retrospective study was to determine the success of Brånemark System TiUnite implants (Nobel Biocare/Sweden) placed in partially or completely edentulous jaws restored with fixed or removable prostheses. PATIENTS AND METHODS: A total of 131 jaws from 110 patients (64 maxillae and 67 mandibles) received 472 implants from July 2003 until March 2008. The patients included 57 men and 53 women, with a median age of 49.6 years and an age range of 16 to 90 years at the time of implant surgery. Twelve maxillae and 10 mandibles were completely edentulous, and 52 maxillae and 57 mandibles were partially edentulous. A single implant was placed in 21 jaws (10 maxillae and 11 mandibles), while multiple implants were placed in the other patients. Among the 131 jaws, removable prostheses were mounted in 10 maxillae and 8 mandibles, and the other jaws were restored with fixed prostheses. RESULTS: Among the 472 implants, 6 maxillary implants and 5 mandibular implants were unsuccessful. The success rate for the implants was 96.56% (96.07% in the maxillae and 97.18% in the mandibles).

Effects of calcium phosphate cement on the peripheral nerve fibers.

Calcium phosphate cement (CPC) is a bioactive ceramic substance. To clarify the effects of CPC on the peripheral nerve, we applied CPC on the peripheral nerve fibers of experimental animals and investigated the nerve fibers by electron microscopy and by immunoblotting analysis using an anti-myelin-associated glycoprotein (anti-MAG) antibody. The results showed that there was neither axonal sprouting at the nodes of Ranvier nor down-regulation of MAG beyond the normal level in the nerve fibers. These findings suggest that there is no harm in using CPC near the peripheral nerve fibers.

Expression of beta-catenin and integrin-linked kinase in the mouse sciatic nerve.

In the present study, the expressions of beta-catenin and integrin-linked kinase (ILK) in the adult mouse peripheral nerve were investigated by means of immunoblotting analyses and electron microscopy using the immunogold pre -embedding method. As a result, beta-catenin and ILK were shown to be expressed both in the axon and the Schwann cell of the myelinated and unmyelinated fibers. By electron microscopy, some molecules of beta-catenin and ILK tended to concentrate under the axolemma in the unmyelinated fibers, while these molecules were distributed in a scattered form throughout the axoplasm in the myelinated fibers. Concerning the cytoplasm of the Schwann cells, the loop region was too slender to detect whether beta-catenin and ILK were associated with the plasmalemma; however, beta-catenin and ILK were distributed diffusely without any relationship in regard to the plasmalemma or the cell organelles around the nucleus region. The density of beta-catenin and ILK around the nucleus region was greater than that within the nucleus region. From these results, some molecules of beta-catenin mediate the axon-Schwann cell adhesion of the unmyelinated fibers, while other molecules are thought to be separated from the cadherin-catenin complex on the plasmalemma. Accordingly, it is hypothesized that the cell-cell adhesion property in the peripheral nerve is not strong but dynamic, and this adhesion is possibly regulated by ILK.

Ror2 expression in squamous cell carcinoma and epithelial dysplasia of the oral cavity.

In this study, the expressions of Ror2 in the normal mucosa, the epithelium dysplasia, and squamous cell carcinoma (SCC) of the oral cavity were investigated, and possible differences in the expression patterns of Ror2 and of p53, Ki67, or PCNA were examined. In Western blotting analyses, Ror2 expression in oral cancer was significantly higher than that in the normal oral mucosa. Immunohistochemically, Ror2 was localized on the plasmalemma and in the rough endoplasmic reticulum (rER). The tissue area with an Ror2-positive expression tended to differ from the area with a positive expression of p53, ki67, or PCNA, and the number of cells with an Ror2 expression tended to increase as the degree of malignancy rose in the epithelial tissues. These results suggest that Ror2 was not related to cell proliferation, but rather associated with cell polarity and cell motility, and that it was also closely associated with the degree of malignancy in oral epithelial tissue.

Two cases of masticator space abscess initially diagnosed as temporomandibular joint disorder.

Diseases causing trismus or pain of the temporomandibular joint (TMJ) include temporomandibular joint disorders (TMJD), trauma, tumors and an inflammation. This report describes two cases of masticator space abscesses causing trismus and TMJ pain, which were initially diagnosed as TMJD. The first case was a 62-year-old female suffering from trismus and right-TMJ pain without swelling or redness, which was diagnosed as TMJD with MRI (TMJ region) findings of bilateral anterior disc displacement without reduction. However, five days later the right-TMJ pain became more severe and MRI (maxillofacial region) revealed a right masticator space abscess. She was treated with antibiotics and underwent an intraoral incision following hospitalization. She recovered well and was discharged from the hospital on the 15th day. The second case was a 68-year-old female having trismus and left-TMJ pain, which was diagnosed as TMJD at another hospital. She received instructions for jaw opening training, but visited our hospital because her symptoms were not improved. At the first visit, the mouth opening range was 18 mm and an anterior dislocation of the left condylar process was found by X-ray imaging. CT-scan revealed an abscess in the left masticator space. Therefore an intraoral incision was performed under general anesthesia and antibiotics were administered. She recovered well and was discharged from hospital on the 12th day. When we treat TMJD, we must keep in mind the possibility of the inapparent presence of some unseen inflammation, especially an abscess formation in the masticator space.

Myofibroma of the mandible.

This article is reporting a case of myofibroma involving the mandible of a 12-year-old boy. The patient did not have any swelling nor any redness but of partial mental nerve hypoesthesia. A panoramic radiograph demonstrated a globe like radiolucent lesion in the left angle of the mandible that was an increased uptake spot by FDG-PET. Incisional biopsies indicated myofibroma, therefore the tumor was totally resected under general anesthesia. After surgery there was no complication except for a change for the worse of unilateral mental nerve hypoesthesia. At 29 months postoperative, no evidence of recurrence could be found.

A clinical study of temporomandibular joint disorders -an analysis based on the Japanese subtype classification-.

In this study, cases of temporomandibular joint disorder (TMJD) were analyzed based on the subtype classification established by Japanese Society for the Temporomandibular Joint (JSTMJ) in 2001. The subject of our investigation consisted of cases who visited to the department of Oral and Maxillofacial Surgery of Kobe University Hospital in 2002 because of TMJD. Among them, any cases with no physical examination or strong psychogenic factors related to their symptoms were excluded. As a result, a total of 195 cases were investigated in this study. These cases consisted of 50 males and 145 females with a mean age of 38.1 years, and they were classified as type I (28 cases), type II (7 cases), type IIIa (91 cases), type IIIb (44 cases) and type IV (25 cases). The most frequently used therapy of the all diagnostic categories was a stabilization type of splint therapy (99 cases), and medication with muscle relaxants (52 cases) or analgesics (50 cases) ranked thereafter. All cases were followed until December 2004, and the results of the treatment were classified into 5 categories of 'improved', 'effective', 'no change', 'deteriorated' and 'discontinued'. No cases with a deterioration of symptoms were observed, while 109 cases (55.9%) were assessed as either 'improved' or 'effective'.

Alveolar ridge augmentation using various bone substitutes--a web form of titanium fibers promotes rapid bone development.

Alveolar ridge augmentation with beta-tricalcium phosphate (beta-TCP) granules, calcium phosphate cement (CPC) powder and web form of titanium fibers (TW) added to Platelet-Rich-Plasma (PRP) was histologically observed for 5 months by the experiments using the maxilla of rabbits. As a result, TW was thus found to promote the rapid bone development within a period of less than 5 months, because TW had an appropriate gap between the titanium fibers for new bone progression. However, titanium fibers remained intact within the maxilla. The CPC powder was transformed into dense cement and also remained intact in the bone. These residual materials must be obstacles to perform the placement of dental implants. On the other hand, beta-TCP granulations were gradually replaced by the new bone, but this process took about 5 months to be completed. Consequently, for an ideal alveolar bone substitute, there needs to be a suitable gap formation within the substitute, such as TW, and properties of total bone replacement, such as that seen in beta-TCP granules.

Ultrastructural localization of alpha E-catenin in the rat sciatic nerve.

Alpha E-catenin is included in the same category as alpha N-catenin, and both of them have been identified as subtypes of alpha-catenin. A previous study issued from our laboratory demonstrated that alpha N-catenin is localized in the axoplasm of unmyelinated peripheral nerves, whereas the localization of alpha E-catenin in the peripheral nervous system has not yet been reported. The present study was focused on the distribution of alpha E-catenin in the rat sciatic nerve. By electron microscopy using immunocytochemical methods, alpha E-catenin immunoreactivities were generally detected in the Schwann cell cytoplasm of unmyelinated nerve and the outer loop of myelinated nerve. Those findings suggest that alpha E-catenin may be associated with Schwann cell-Schwann cell or axon-Schwann cell contacts.

N-/R-cadherin expression in dorsal root ganglia and spinal cord.

Localizations of N- and R-cadherins in dorsal root ganglia and lumbar spinal cord of the chick were immunocytochemically examined. As a result, N- and R-cadherin appeared to be co-localized on plasmalemma of neurons in dorsal root ganglia that were in contact with satellite cells, whereas there was no expression in neurons of the ventral horn. These findings indicate the possibility that expression pattern of cadherins in the peripheral neuron differs with its functional property (e.g. sensory or motor).