Gagging as a symptom of induced anxiety reactions]

In the light of personal studies and relevant reports in the literature, the authors deal with gagging during dental treatment and after denture insertion. In this connection, aetiopathologic and therapeutic aspects of the gagging syndrome are analysed. It is postulated that the gagging reaction is a conditioned anxiety reaction.     

Mast cells of the human gingiva

Comparative histochemical studies with specific regard to the demonstration of mast cells were carried out on 21 different chronically inflamed marginal gingival specimens. For the demonstration of sulphated acid mucopolysaccharides two metachromatic stains were used-toluidine blue (pH 1.0) and acridine orange (pH0.5)-, as well as one orthochromatic stain- astra blue (pH 0.2–0.3). In addition the alcian blue-safranin sequence was employed to distinguish between weakly and strongly sulphated mucopolysaccharides. Trypsin-like esterase activity was demonstrated by the EACNAS-GBC technique. The metachromatic stains used stain mature mast cells specifically, while the non-metachromatic techniques stain immature mast cells as well. The chemical backgrounds for the different staining reactions are discussed. The chronically inflamed human gingivae were found to be rich in both mature and immature mast cells. The great majority of the immature mast cells were found within the pocket area of the connective tissue. Here, the number of mature mast cells was significantly smaller than in the oral area. The distribution of the different mast cell variants indicate a relation between mast cells and diffusible products from the gingival bacterial plaque.     

Prospective study on titanium bar-retained overdentures: 2-year results

Within a monometallic concept 29 patients received titanium bar‐retained mandibular overdentures on 2 IMZ implants. The study had a prospective design with 3 months recall intervals. One of 58 implants failed after 11 months. There were no significant differences of the mean plaque scores (Silness, Löe) and the mean sulcus bleeding scores (Mühlemann, Son) at the abutments between baseline, 12 months and 24 months. Less than 40% of the subjects showed plaque score zero at 24 months. However, 89% exhibited sulcus bleeding score zero indicating health of the peri‐implant soft tissues in most cases. Plaque at the basal site of the bar was scored separately at additional measuring points located at the central area and the contact areas between bar and abutments. Bar plaque scores nearly doubled between baseline and 12 months and remained high at 24 months. Median maximal vertical bone loss around the implants was 1.7 mm after 2 years. Bone loss did not exceed one quarter of the implant length in 79%. The monometallic concept in bar‐retained overdentures on 2 implants proved its clinical suitability except for the applicability of pure titanium for bar clips. Plaque formation beneath the bar seems to be one of the major clinical problems.     

Five-year evaluation of implants placed at extraction and with dehiscences and fenestration defects augmented with ePTFE membranes: results from a prospective multicenter study

Background: Barrier membranes have been used to promote bone ingrowth on implants with dehiscences and fenestrations. Membranes also have been used to protect defects adjacent to implants placed at the time of extraction. The concept of guided bone regeneration relates to preferentially allowing cells from bone to migrate into various defects while excluding fibrous tissue and epithelium. The purpose of these procedures is to enhance bone-to-implant contact at the treated sites and to prevent mucosal complications. Purpose: The purpose of this article is to report clinical outcomes for implants placed at the time of extraction and augmented with expanded polytetrafluoroethylene (ePTFE) and followed for 5 years. The outcomes for implants with dehiscences and fenestrations augmented with ePTFE barriers and followed up to 5 years also are reported. Methods and Materials: Four treatment centers participated in this study (Tucson, Gothenburg, Spokane, and Leuven). In the extraction group, teeth were removed for varying reasons, and Brånemark implants were placed and stabilized within the host bone. Defects present at the coronal implant aspect were covered with ePTFE barrier membranes. Flaps were rotated to cover the membrane-treated sites. If exposure of the material occurred prior to second-stage surgery, the membranes were removed. Barriers remaining unexposed were removed at second-stage surgery. The implants were followed up to 5 years. In the fenestration and dehiscence group, implants with exposed threads were augmented with ePTFE barrier membranes. The barriers were removed at appropriate intervals, and the patients were followed up to 5 years. Radiographic measurements were made from nonstandardized periapical radiographs at abutment connection and 1, 3, and 5-year follow-up visits. Results: Forty patients participated in the extraction group. They received a total of 49 implants. Three implants failed prior to loading. The 5-year cumulative survival rates for implants placed at the time of extraction were 93.9% and 93.8%, respectively, for maxillary and mandibular implants. The average maxillary mesial and distal marginal bone loss (1–5 yr) was 0.3 mm (standard deviation [SD] = 1.5) and 0.3 mm (SD = 1.0). In mandibles, the average mesial and distal bone loss (1–5 yr) was -0.2 mm (SD = 0.5) and -0.05 mm (SD = 0.6), respectively. The dehiscence and fenestration group included 44 patients. Twenty-six were followed for up to 5 years. Eight patients experienced total implant failure. For dehiscences and fenestrations, the cumulative survival rates were 76.8% and 83.8% for maxillary and mandibular implants, respectively. The average maxillary mesial and distal bone loss (1–5 yr) was 0.4 mm (SD = 0.8) and 0.2 mm (SD = 0.9), respectively. In mandibles, the average mesial and distal marginal bone loss was 0.3 mm (SD = 0.9) and 0.3 mm (SD = 0.8), respectively. Conclusions: Implants placed at the time of extraction and augmented with ePTFE barrier membranes have favorable long-term predictability. On the other hand, long-term evaluation of implant dehiscences and fenestrations augmented with barrier membranes indicates that they have less favorable 5-year survival rates. Membrane augmentation of these may be questioned.     

Dental injuries in association with mandibular condyle fractures

Abstract A total of 356 patients with mandibular condyle fractures were studied regarding associated dental injuries. One third of the patients had injured teeth, on average, 3.7 teeth had been injured per accident. Dental traumas were distributed equally between the anterior (incisors and canines) and posterior teeth (premolars and molars) in both jaws. In unilateral condylar fracture cases maxillary dental injuries involved more often premolars and/or molars of the fracture side than those of the non-fracture side. The mean number of dental traumas in the mandible was higher in cases of simultaneous mandibular body fracture than without, whereas the presence of mandibular body fracture did not affect number of associated dental injuries in the maxilla. The dental injuries were mostly to hard tissue (78%), which were commonest in men, 20 to 29 years of age, and in victims of violence or fall accidents. Severe dental injuries in association with mandibular condyle fractures were more common in accidents due to traffic and miscellaneous causes than in those due to violence. Severe dental injuries were more often encountered when simultaneous mandibular body fracture was present than when it was not and more so in bilateral than unilateral condylar fracture cases. The most important factor correlating with the severity of dental injuries was the presence of bilateral condylar fracture.     

Review of severe osteoradionecrosis treated by surgery alone or surgery with postoperative hyperbaric oxygenation

We reviewed 41 patients with osteoradionecrosis of the mandible. Each patient was treated by radical resection followed by external beam irradiation. The diagnosis of infected osteoradionecrosis was confirmed clinically, radiologically, and histologically. After operation had failed, 20/41 were given hyperbaric oxygen (HBO) as in 'salvage' treatment. Daily sessions of HBO 2.5 ATA for 60 minutes (mean: 29 sessions) were given. The other 21 patients were treated by operation and antibiotics alone. HBO group (n = 20): The overall success rate for HBO after operation had failed was 13/20. Repeated debridement as first-line treatment followed by postoperative HBO was successful in 12/19. In seven of 19 patients, partial mandibulectomy and microvascular transplantation were required as second-line treatment, and this was successful in five. Primary partial mandibulectomy and microvascular transplantation followed by HBO was successful in 1 patient. Non-HBO group (n = 21): Repeated debridement was successful in 10/11 patients. Partial mandibulectomy was required as second-line treatment in the remaining one. In the other 10, partial mandibulectomy and microvascular transplantation were successful as first-line treatment in four. In the remaining six, further surgical intervention became necessary and were successful for 5-17 months (mean: 13). With a success rate of 13/20, we do not recommend HBO for the treatment of osteoradionecrosis.     

Lower lip sucking habit treated with a lip bumper appliance

The patient was an 11-year-old girl with a lower lip sucking habit with increased overjet, maxillary generalized spacing, and mandibular incisor irregularity. Hyperactivity of the mentalis muscle and deepening of the labiomental sulcus because of the abnormal sucking habit was observed. Orthodontic treatment was started with a lip bumper appliance to break the lower lip sucking habit and continued with fixed orthodontic mechanotherapy. The lip bumper appliance therapy resulted in the elimination of the lower lip sucking habit, musculus mentalis hyperactivity, and labiomental strain in addition to a gain in arch length, improvement of the lower incisor inclinations, and overjet reduction.     

Band and loop space maintainer--made easy

Space maintainers have been used in Pediatric Dentistry for many years. The use of these appliances, however, in terms of indications, contraindications, design and construction has gained little attention from researchers. This paper highlights the construction of a new technique of fabrication of band and loop space maintainer. The advantages of this new Direct technique or Single sitting technique over the conventional technique are discussed.     

Effect of operators' skills on increase in cavity volume of restorations.

OBJECTIVE: The purpose of this in vitro study was to evaluate the change in cavity volume after removal of amalgam and resin composite restorations, based on the dental skills of the operators. METHOD AND MATERIALS: A high-speed turbine and diamond burs were used to prepare Class II cavities in 60 acrylic resin mandibular first molar teeth. After the teeth were weighed with precision scales, the cavities were restored with amalgam or posterior resin composite. The restored teeth were then stored in distilled water at room temperature for 48 hours. Three undergraduate students with 2 years' practical experience on patients, and three postgraduate students with an additional 4 years' practical experience in the Department of Operative Dentistry, removed the restorations from the cavities with a high-speed turbine, and the teeth were all weighed again. After cavities were rerestored with the same materials, each restoration was removed once more by the same operator. The weighing procedure was repeated before and after the removal of the restorations. The data were subjected to paired and unpaired t tests. RESULTS: Every time a restoration was removed from a tooth, the cavity preparation became significantly larger, but the postgraduate students caused significantly smaller increases in cavity volume. CONCLUSION: Increases in cavity volume are not based on the nature of t he restorative material; however, the individual experience levelsand dental skills of the operators lead to significant differences in the cavity volume increase.     

The incidence of cysts and tumors around impacted third molars

The objective of this retrospective analysis was to determine the incidence of the development of cysts and tumors around third molars and to discuss some relevant issues in relation to the removal of asymptomatic, impacted third molars. 9994 impacted third molars, removed in 7582 patients, formed the basis of this study. The analysis revealed 231 cysts (2.31%) and 79 tumors (0.79%), including 7 benign tumors (0.77%) and two malignant tumors (0.02%). The incidence of cysts and tumors around impacted third molars was 3.10%.