[The quality of oral healthcare for edentulous individuals]. / De kwaliteit van de zorgverlening voor edentaten.

Fabricating removable complete dentures is a rather complicated treatment. The quality of the care delivered is broadly determined by 2 factors: the technical result and the way in which the individual patient experiences and evaluates the treatment. Healthcare professionals who carry out this treatment are subject, with respect to their capability, to the Dutch Individual Healthcare Professions Act. In cases of persisting complaints or problems, edentulous individuals are often treated with an overdenture on oral implants. Several oral healthcare providers are then involved in the treatment. In order to clarify procedures, a trajectory of care is presented in which all of these oral healthcare providers are located. It is expected that the number of edentulous individuals will decline and that the degree of treatment complexity will increase. To guarantee future efficiency and quality of care delivery, a number of regionally distributed national centres of expertise should be established.

Growth of micro-organisms from supragingival dental plaque on saliva agar.

The role of saliva in supporting the growth of dental plaque has scarcely been investigated. We have studied the growth and recovery of micro-organisms from dental plaque samples on saliva-agar plates, prepared from filter-sterilized wax-stimulated whole saliva. Under optimal conditions, the mean recovery of plaque samples on saliva agar was about 50% (range, 22-77) of the recovery on blood agar. Addition of 2.5 mmol/L dithiothreitol (DTT) strongly facilitated filter-sterilization of saliva, but DTT concentrations higher than 1 mmol/L reduced the recovery of plaque micro-organisms on saliva agar. Catalase (100 U/ml) offered protection against the inhibitory effect of DTT. Addition of glucose (1-5 mmol/L) increased only slightly the recovery of plaque micro-organisms on saliva agar. When supragingival plaque was plated on saliva- and blood-agar plates, the composition of the microflora isolated from saliva agar strongly resembled that isolated from blood agar. The predominant species--i.e., Streptococcus and Actinomyces--all grew on saliva agar though usually in numbers somewhat lower than those on blood agar. In addition, most species normally found only in low proportions in supragingival dental plaque were also found to grow on saliva agar. Collectively, the results lead to the conclusion that the supragingival microflora can utilize saliva as a complete source of nutrients.

Differences two years after tooth extraction in mandibular bone reduction in patients treated with immediate overdentures or with immediate complete dentures.

In a randomized controlled clinical trial, 74 patients who required immediate dentures were randomly treated with immediate overdentures on two lower canines or with immediate complete dentures. Mandibular bone reduction was measured by use of oblique lateral cephalometric radiographs made at baseline and the results compared with those of one year and two years after denture treatment. Analysis of the data showed that the average bone reduction in the lower canine regions in the first year was 0.9 mm in the immediate-overdenture group and 1.8 mm in the immediate complete-denture group. In the posterior parts of the mandible, the bone reductions were, respectively, 0.7 mm and 1.9 mm. The differences were statistically significant in all measured regions. During the second year, no significant differences in bone reduction were found. The sums of differences in the first two years were significant in all regions except the molar region, preserving the initial difference. Retention of roots of canines beneath a mandibular denture in immediate denture patients, even when they were in poor condition, reduced the collapse of the alveolar processes in all regions of the mandible.

[Sequelae of tooth loss for the potential for chewing in the elderly]. / De gevolgen van tandverlies voor het kauwvermogen van ouderen.

The dentition is a part of the orofacial system. It has important functions such as speech and chewing. However the question is whether masticatory function declines when more loss of teeth occurs. In this article attention is given to the masticatory process and the masticatory performance in relation to complete or partial tooth loss and to the question to which requirements the dental prosthesis has to come up in relation to the food intake and the masticatory performance.

Occlusion for maxillary dentures opposing osseointegrated mandibular prostheses.

This paper presents a combination of several occlusal concepts designed to contribute to the successful use of maxillary dentures in opposition to osseointegrated mandibular prostheses. To ensure a positive outcome when designing such an occlusion, three factors must be considered: patient satisfaction, maxillary anterior bone preservation, and mandibular arch shortening. It is recommended that for centric occlusion the molars have a lingual contact occlusion, the premolars have a buccal contact occlusion, and the anterior teeth have an open occlusal relationship. For an eccentric occlusion, a balanced articulation is favored instead of mutually protected occlusion.

Treatment results with immediate overdentures: an evaluation of 4.5 years.

In a controlled clinical trial, 74 patients who required complete immediate dentures were randomly treated with immediate mandibular overdentures on two mandibular canines with or without magnetic attachments or with complete immediate dentures. All were borderline situations for overdenture therapy. The patients were evaluated for 4.5 years after denture insertion. The results demonstrated that 50% of the dentures had been renewed or had required replacement; in this respect, no differences were found among the three groups. In the overdenture groups, 15% of the abutments were extracted; most abutment restorations were replaced or had to be replaced. Two thirds of the magnets were lost or in bad condition. No significant differences were found in relation to patient satisfaction; most patients were satisfied with their dentures. It is the authors' opinion that even though the abutment conditions were disappointing after 4.5 years, mandibular overdenture therapy is indicated in borderline situations because of the 50% reduction in mandibular bone loss found.

Growth of oral Streptococcus species and Actinomyces viscosus in human saliva.

Microorganisms in dental plaque live in constant association with saliva. The role of saliva in the adherence of bacteria to the teeth and the antibacterial properties of saliva have been well investigated; less interest has been shown in the possible role of saliva as a substrate for oral microorganisms. In this study it was shown that saliva can serve as a growth medium for oral Streptococcus spp. and Actinomyces viscosus. The cell production of these organisms on saliva was carbohydrate limited. The doubling times for growth on glucose-supplemented saliva (4 to 5 mmol/liter) ranged from 1.6 to 4.0 h. The availability of carbohydrate sources for the oral microflora is discussed in relation to microbial growth in the oral cavity.