Eight-year retrospective study investigating tooth survival after primary non-surgical root canal treatment in a UK military cohort.

INTRODUCTION: Root canal treatment (RCT) plays an important role in preserving the dentition by deferring other invasive treatments. Data on tooth survival and predictive factors for tooth loss after RCT in the military cohort are lacking. This investigation aimed to determine the proportion of teeth surviving in an 8-year period after RCT and identify potential predictive factors for tooth loss in a UK military cohort. METHODOLOGY: A retrospective review of an integrated electronic health record for military patients who had received RCT was performed in a random sample of 205 patients (n=219 root-filled teeth) who had received RCT between 1 January 2011 and 1 January 2012. Tooth survival was defined as tooth presence, regardless of signs or symptoms, and measured from the point of root filling until either the end of the designated study period or time of extraction. Survival was evaluated using Kaplan-Meier estimates and association with tooth loss using the χ2 test. Potentially significant predictive factors were investigated using univariate Cox regression. RESULTS: Tooth survival following RCT was 98% after 24 months; 88% after 48 months; 83% after 72 months; and 78% after 96 months. Four predictive factors were found to affect tooth loss as follows: preoperative pain (HR=3.2; p<0.001), teeth with less than two proximal contacts (HR=3.0; p=0.01), teeth with cores involving more than two surfaces (HR=2.0; p=0.03) and postoperative unscheduled dental attendances (UDA) (HR=2.7; p=0.01). CONCLUSIONS: Within the limitations of this study, the presence of preoperative pain; teeth with less than two proximal contacts or with cores involving more than two tooth surfaces; and occurrence of postoperative UDA were found to significantly increase the hazard of tooth loss.

Botulinum toxin treatment of essential palatal myoclonus tinnitus.

OBJECTIVE: The purpose of this study was to review the use of botulinum toxin in the treatment of essential palatal myoclonus tinnitus. DESIGN: Two case series. METHOD: Four to 10 units of botulium toxin are injected into the tensor veli palatini muscle. The dose and interval between doses is titrated according to patient symptoms. With bilateral symptoms, injection is alternated between sides at sequential visits. OUTCOME MEASURES: Relief of tinnitus with cessation of palatal contractions. RESULTS: Both patients had relief of tinnitus. One patient required ventilation tube placement to relieve aural fullness. CONCLUSIONS: Tensor veli palatini botulinium toxin injection is an effective treatment for essential palatal myoclonus tinnitus.

Selection of biomaterials for middle and inner ear implants.

In the selection of biomaterials for middle ear applications of implantable devices, certainly the site of implantation and the mass of the implant will dictate the choice of biomaterials. Hermetic sealing of an implant is best achieved by the use of metals, not polymers. Osteocompatibility of an ossicular implant can be enhanced by the incorporation of calcium phosphates such as hydroxyapatite coatings. Finally, osseointegration or osseofixation is neither necessary nor desirable for ossicular implants, because (1) they may need to be removed or replaced in the future and (2) their solid fixation to an ossicle is not necessary for the vibratory function of hearing amplification.

Intratympanic gentamicin instillation as treatment of unilateral Menière's disease: update of an ongoing study.

A prospective study using intratympanic gentamicin instillation as treatment for disabling unilateral Meniere's disease has been ongoing at our institution for 4 years. Treatment effectiveness is evaluated based on the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) 1985 guidelines. This report is based on 30 patients who have become eligible for assessment. We conclude that gentamicin intratympanic instillation as currently used in our protocol is an effective, safe, and easily administered method of achieving a predictable measure of vertigo control.

Treatment of Menière's disease with topical gentamicin: a preliminary report.

We evaluated the hypothesis that topical intratympanic gentamicin can relieve the vertigo of disabling Menière's disease, reduce or ablate vestibular caloric excitability, and preserve hearing. Between July 1988 and June 1989, 33 patients were treated in the Dizziness Unit at the Sunnybrook Health Sciences Centre in a prospective controlled trial. This preliminary report presents the results of 29 patients with follow-up averaging 8.3 months and ranging from one to 18 months. All patients had either complete (86.2%) or substantial (13.8%) control of vertigo. Caloric excitability was ablated in 63% and reduced in 25.9% of subjects. Hearing was improved in 35.7%, unchanged in 39.3%, and worse in 25.0% of patients. In this preliminary review, the overall success rate for this treatment is 89.7% if control of vertigo and improvement in disability level are the criteria examined.

Chemical labyrinthectomy: local application of gentamicin for the treatment of unilateral Menière's disease.

The use of aminoglycosides for selective vestibular function ablation without hearing alteration is described in the literature. Parenteral administration of streptomycin for the alleviation of vertigo in cases of bilateral Meniere's disease is well accepted. The instillation of aminoglycosides into the middle ear to produce a similar result, has been successfully used in the treatment of unilateral Meniere's disease. However, the use of chemical vestibulectomy has not gained acceptance as a practical means of treatment when compared to vestibular neurectomy. The reason for this is not clear, but may stem from the lack of definitive protocol for the application and lack of treatment results that have been assessed according to an acknowledged standard (i.e., the American Academy of Otolaryngology Criteria). A prospective study was undertaken to examine the efficacy of chemical vestibulectomy as the treatment for vertigo in unilateral, incapacitating Meniere's disease. A standardized drug administration protocol was utilized, and academy criteria for the assessment of treatment were applied. This report details the first group of patients to complete 2 years of post-treatment follow-up. Based on our experience, we conclude that chemical vestibulectomy is an efficient alternative to surgery. A standardized regimen of drug administration that can be carried out on an outpatient basis is put forward.

Cerebrospinal fluid leaks and meningitis in acoustic neuroma surgery.

Cerebrospinal fluid leaks and associated meningitis are the most common life-threatening complications of surgery for acoustic neuromas. This retrospective study reviews 319 patients who had surgery for 321 acoustic tumors at the Sunnybrook Health Sciences Center, University of Toronto, from April 1975 to March 1990. Cerebrospinal fluid leaks occurred after 13.4% of primary tumor operations. Surgical repair was required in 6.2% of all patients; 4.4% needed more than one operation. Meningitis occurred in 5.3% of all patients. These complications were more common in larger tumors and after the combined translabyrinthine middle fossa approach. Transnasopharyngeal eustachian tube obliteration was used to stop recurrent cerebrospinal fluid leaks in two patients.

The cross-sectional osteology of the midface.

The midface is a complex anatomical region composed of spaces created by a partitioned bony case. Otolaryngologists must thoroughly understand the organization of this region and be able to relate its structure to both pathological processes and surgical therapy. This study examines serial cross-sections of clear polyester-embedded skulls. The midfacial skeleton is resolved into a series of geometric shapes: the pentahedral orbit resting on the tetrahedral maxillary sinus, the wedge-shaped ethmoid pyramid occupying the upper outer quadrant of the v-roofed naso-ethmoid box which is related anteriorly to the folded-disk frontal sinuses and external nasal wedge, and posteriorly to the sphenoid box and triangular pterygopalatine fossa wedge. We show that the weakest region of the fovea ethmoidalis is the lateral wall of the olfactory groove, and we examine the co-planar relationship of the medial maxillary and orbital walls.