Skin and mucous membranes including the oral mucosa are among the preferential locations of opportunistic infections and secondary neoplasms in patients infected with the human immunodeficiency virus (HIV). Infections of the oral mucosa such as thrush occur in a high percentage of AIDS patients, patients with AIDS-related complex or HIV-seropositive individuals. The clinical appearance of the infections (herpes virus infection, periodontitis) is often marked by aggressive expansion, frequent recurrences or resistance to therapy. Oral "hairy" leukoplakia is considered to be a characteristic lesion in HIV-infected individuals. Tumors like Kaposi's sarcoma, squamous cell carcinoma and non-Hodgkin lymphoma of the oral mucosa may cause marked morbidity in AIDS patients. Such oral lesions are frequently the first indication of an HIV-infection. Dentists should be aware of the oral manifestations of HIV-infection and initiate diagnostic and therapeutic measures in the interest of the patients and for epidemiologic reasons.
The components of the bonding system Wiron 88--Superbond enamel, dentin were examined by scanning electron microscopy and profile scanning. Wiron 88 was corroded electrolytically using Korolyt A in the Eltrokor system. At 400 mA/cm2 and an exposure time of 7 minutes an optimal microretentive surface morphology was seen on SEM. Both shorter and longer exposure times did not produce the desired results. Profile scanning of corroded Wiron 88 to determine vertical and horizontal surface changes showed that surface roughness increased as a function of increasing exposure times. On SEM of the Superbond material placed in contact with corroded metal and enamel, retentive structures were found to spread, thus producing a micromechanical bond. Phosphoric acid treatment increased the diameter of the dentin canals so that penetration of Superbond in corroded dentin was better than in non-corroded dentin. These results and several years of clinical experiences in adhesive denture work establish the usefulness of combining electrolytically corroded Wiron 88 and Superbond.
Periodontal pre-treatment of patients receiving partial dentures should involve three phases: initial therapy; periodontal surgery; home care. For periodontal surgery and/or prosthodontic treatment using precision materials, e.g. telescope retainers, the API (approximal plaque index) should not exceed 30%. To prevent further loss of gingival attachment due to iatrogenic irritation by the dentures preparation of abutments should consistently the para- or supragingival. In patients with few residual teeth telescope retainers, which can be cemented for definitive fit if indicated, are the treatment of choice.
In fully or partially edentulous patients with mesial bite undergoing surgical correction, the possibilities for avoiding intermaxillary fixation were studied. For stable osteosynthesis of mandibular osteotomies preoperative prostheses are needed in these patients to keep the jaws in their proper relation during surgery. This requires cephalic adjustment of the maxillary cast and articular adjustment of the mandibular cast in the articulator. The mandibular cast is shifted along an aluminum wedge designed to match the inclination of the occlusal plane until the alveolar rests are in proper relation to one another. If the occlusal plane is neglected, uncontrollable tilting of the mandible may occur. This may favor relapses. As Slavicek (1984) showed the mean inclination of the occlusal plane relative to the hinge axis-orbital plane to be 12.87 degrees (scatter 5.99 degrees) with dorsal convergence in 1,213 patients, 3 aluminium wedges with different inclinations were designed. These are suited for 92.5% of all cases with tolerances of +/- 3 degrees. Mandibular casts are pasted to geometric paper and shifted along the aluminium wedge to the desired position; the distance they are shifted is read from the paper. This distance is transferred to the teleradiograph and the changes in profile are checked. Preoperatively, prostheses can then be tailored to match the desired alveolar crest relation. During surgery, these prostheses serve as splints for setting the mandible as designed in the model. The osteotomy fragments are then screwed together transbuccally with miniscrews and clawed washers. The latter provide for a firm seat of the traction screws in the mandible at a safe distance from the mandibular canal. Postoperative intermaxillary fixation can thus be avoided.
Free mucosal grafting is a simple, safe and predictable procedure. It is indicated in the treatment of progressive recessions in patients with reduced attached gingiva, in recurrent traumatic marginal lesions inspite of correct tooth brushing, in refractory dental neck hypersensitivity and for cosmetic reasons in patients with recessions. In these situations advancement grafting is done as a secondary procedure. To prevent the potential occurrence of recessions free mucosal grafting may also be indicated prophylactically before orthodontic or prosthetic management. The management concept in patients with recessions as well as the indications of the procedure, the technique used at our department and aspects of planning surgery are discussed.
The trend towards esthetic dentistry, which originates in the USA, has added new dimensions to the treatment of anterior teeth. One of it is the porcelain laminate technique. Using composites, extremely thin, manually prepared porcelain laminates with a thickness of 0.3 to 0.5 mm are bounded to the labial aspect of front teeth or laterals. On account of the low laminate thickness very little enamel preparation is needed. The residual enamel mass and the translucency of the ceramic material produce a natural appearance and optimal cosmetic results. This technique enables the dentist to restore the shape and color of esthetically compromised teeth.
If ceramic inlays and onlays are considered in restorative work, some operations which, more than in other areas of dental engineering, decide upon the success or failure should be given special attention. During the preparation of ceramic inlays care should be taken to produce well rounded rather than rectangular edges approximally. In the case of onlays there should ideally be a smooth circular step rounded axially with a sharp-edged near-rectangular interface with the non-ground tooth. Ceramic inlays and onlays are best inserted with the adhesive technique, which provides for an improved strength of the ceramic material, an adequate marginal adaptation and a satisfactory cosmetic appearance. As long-term results are not yet available, the use of ceramic inlays and onlays is still experimental.
Axiographic images of eccentric condylar paths can be more reliably interpreted by considering the clinical function data, compression test results and the MPI. In the case presented the abnormal position of the right condyle would have gone unnoticed without such a combined approach to the problem.
Data obtained by computer tomography of the TMJ were compared with those of clinical and instrumental analyses of function. 25 females and 37 males aged between 19 and 47 years (mean age, 24.8 years) were examined. None of the patients complained of functional problems subjectively, but clinical analysis of function showed several signs of stomatognathic dysfunction to be present. Results of CT did not correlate with those of clinical and instrumental analysis.
43 atrophic left hemimandibles were divided by 6 saw cuts made between the mental foramen and the third molar to analyze the location of the mandibular canal. Mandibles were classified by the severity of alveolar absorption using Atwood's classification and changes in the distances of the mandibular canal from the superior and inferior borders of the mandibular body were correlated wit the degree of atrophy. Measurements were obtained with a digitizer and a computer and results were analyzed statistically. The following statistically significant observations were made: The distance of the mandibular canal to the external lingua and buccal cortical layers did not change with increasing atrophy, but remained remarkably constant. By contrast, highly significant changes in the distance of the mandibular body were found to be present. These were more pronounced at the superior than at the inferior border. The changes seen were consistently most severe at the level of the first molar. Prior to surgical interventions involving an atrophic mandible the location of the mandibular canal should invariably be identified by imaging techniques such as orthopantomography, telemetric X-rays, tomographies, CT and MRI, if indicated, in order to avoid injuries of the inferior alveloar nerve and preclude forensic consequences.
Whole jaw models of 6 different materials were examined for their transverse dimensional stability. Under standardized conditions impressions were made of a mandibular phantom with 4 stylized crown stumps using the double mix-spray technique with additively cross-linking silicon. Of these, test models were prepared and measured using the original model as reference. The high-strength dental stones Die Keen and Fuji Rock showed the highest dimensional stability. On account of their shrinkage during polymerization, the epoxy resins Blue Star E and Metapox as well as Blue Star P, a polyurethane, were found to have smaller transverse stump interspaces. Data for electroplated silver models were between those for dental stones and plastic materials.
In a prospective trial involving 17 patients with head and neck tumors an attempt was made to relate the occurrence of stomatitis during cytostatic chemotherapy to changes in the resident microbial population, if any. Of the 17 patients who received the same cytostatic regimen, 10 developed stomatitis after a mean interval of 12 days. Smears were taken of the 2 patient subgroups (with and without stomatitis) at the onset of treatment and after comparable intervals during treatment and compared to those of a normal control group. Pretreatment smears did not show any quantitative or qualitative differences in the aerobic and anaerobic microbial spectrum between the 3 subgroups examined. During treatment patients developing mucositis were found to show a statistically significant multiplication of pathogens, while the other 2 groups still did not differ from one another. Together with the direct cytostatic effect of chemotherapy, proliferation of pathogens in the oral cavity appears to contribute to the development of stomatitis.
The overriding principle in surgery should always be "nihil nocere". This is particularly true for maxillofacial surgery and assumes critical importance in orthognathic operations in which the prevention of motor and sensory nerve lesions should have priority. Considering that orthodontic surgery is increasingly done in an ever growing number of situations, it is obvious that this issue has become central to the decision-making process in each and every case. This contribution is designed to review the basic anatomy, to outline a useful surgical management concept and present the results obtained with it.
This investigation provides evidence showing the significance of recipient tissue inflammation for the prognosis of wisdom bud transplantation. Transplantation of wisdom buds has become an established method for preserving masticatory function after extraction of first molars. Previous investigations showed that the time interval between the extraction of the first molar and the implantation of the bud tooth at its site was important for the success of transplantation. The present study indicated that complete epithelialisation of the external wound was a much more significant factor for the success of transplantation than a defined time interval between the 2 procedures.
Under sterile conditions human costal cartilage is explanted, stripped of perichondrium, deep-frozen and lyophilized for 72 hours. Then single grafts are packaged and gas sterilized. 8 hours before implantation grafts are rehydrated in an antibiotic solution. 19 extensive dentogenous cysts were packed with lyophilized bruised cartilage. Healing was uncomplicated in all cases. A definitive assessment of ossification is not yet possible.
An epidemiological study involving 764 women aged from 25 to 64 years revealed at least one carious and/or filled root surface in 40% of all subjects. The number of teeth and tooth surfaces affected by root caries continuously increased with age. Prevalence has tripled after the age of 45. By contrast, the risk of caries shows no dependence on age. The highest root caries prevalence is found in the molars of the mandible and in the canines of the maxilla; the lowest attacked tooth type is in the lower incisors. Root caries is most frequently found on all buccal surfaces of molars in the mandible and on the oral surfaces of molars in the maxilla.
The condition of the peri-implant mucosa is critical for the long-term success of endosteal implants. 111 endosteal implants (IMC and Brånemark) were examined to see whether peri-implant gingival attachment to bone and peri-implant inflammatory reactions correlated with implant stability. A direct relation was found exist between peri-implant mucosal attachment and pocket depth around implants, while the severity of peri-implant inflammatory reactions did not correlate with implant stability. But this might be explained by the relatively short implant residence of 5 years at the time of the follow-up study.
The bioavailability of fluoride (F) is not known to be reduced by any food except for milk and milk products. Their effect on F bioavailability can, however, be reduced or altogether abolished by the ingestion of solid food. Solid food intake also enhances the extraction of F from poorly soluble compounds like CaF2. The reduction of F availability by milk is thought to be attributable to binding of F as milk curdles in the stomach. Improved utilization of F by solid food intake may be explained by the prolonged retention of the chyme in the upper gastrointestinal tract, which would leave more time for F to be released from curdling products and bound forms as e.g. CaF2. Simultaneous intake of F and food produces lower serum F levels; these are, however, sustained longer than in fasted subjects. The lower peak levels may well reduce the risk of enamel mottling, while the prolonged serum F levels may produce sustained F concentrations in the oral cavity by salivary F erection. These would prevent caries.
The influence of different galactose concentrations on the cariogenic effect of Streptococcus mutans (strains: DSM 20381 and DSM 20523) in a sucrose diet (33%) was examined in an animal experiment. The treated Wistar rats were free of pathogenic germs at the beginning of the experiment. The experimental conditions were approximately in accordance with the "Consensus statement" of the American Dental Association. The sides of the teeth, the amount of film, the abrasion of the chewing surfaces, the amount of surface and fissure caries and the animals general condition were evaluated. The anticaries effectiveness of galactose is dependent on its concentration: 5.0% galactose reduces the amount of caries on a high significance level, lowers the abrasion of the chewing surfaces, possibly because of the increased amount of serum calcium related to this galactose concentration, and diminishes the amount of film. 1.5% galactose prevents caries significantly and strongly reduces the amount of film; 0.5% galactose reduces the amount of caries non-significantly, but diminishes the amount of film. The effect is based on the property of galactose to occupy the receptors of the pellicle (layer of glycoprotein on the tooth enamel), hence the adherence of specific germs (for example, Streptococcus mutans) ceases in whole or in part.
In a follow-up study of 24 patients with mesial bite operated on at the Department of Oral and Maxillofacial Surgery, University of Innsbruck Medical School, relations between the outcome of sagittal splitting and myofunctional disorders were investigated. Orofacial imbalances of variable extent were found to be present in 16 of the patients followed up. Effects of myofunctional factors on occlusal position, occlusion, overbite and overjet are reviewed. Five patients with particularly severe myofunctional disorders underwent detailed logopedic and myofunctional evaluation. Results are presented. As myofunctional factors may profoundly affect the late results of surgery, it is concluded that patients with myofunctional disorders should undergo adjuvant myofunctional rehabilitation before or at least after surgery in order to prevent relapses.
