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Biomedical subjects

D van Steenberghe

Publications and source records attributed to D van Steenberghe.

At least 19 recordsLinked to original sources
PubMed1999

Bone behavior around sleeping and non-sleeping implants retaining a mandibular hinging overdenture.

Since 1984 2 implants in the symphyseal area have been used in our center to retain a hinging overdenture. Because this technique was unknown at that time 1 extra implant was installed in between the 2 others and was left submerged (sleeping). The extra implant served as a rescue implant in case 1 of the 2 others would fail. It was the aim of the present report to compare the marginal bone behavior around those sleeping and non-sleeping implants. Between 1984 and 1987 20 completely edentulous patients were provided with 3 implants (Brånemark system), where from 2 were used to retain a hinging overdenture. Ten years later half of the patients could still be traced. Retroalveolar radiographs were made at the abutment installation and after 10 years. None of the non-sleeping or sleeping implants lost, at an individual basis, more than 1.6 and 0.7 mm of marginal bone respectively. On average, non-sleeping implants lost at the right- and left-hand side of the mandible 0.33 and 0.57 mm of bone respectively. However, sleeping implants lost on average 0.16 mm only. Thus non-sleeping implants lose on average more bone when compared to sleeping implants. Surgical trauma at the abutment connection is believed to be the most plausible cause of marginal bone loss around non-sleeping implants.

Aged↗
PubMed1999

A long-term evaluation of composite-bonded natural/resin teeth as replacement of lower incisors with terminal periodontitis.

BACKGROUND: In patients with severe peridontitis, lower incisors are prone to terminal breakdown. This study assessed the longevity of composite-bonded resin/natural teeth (reinforced only with a stainless steel mesh) as replacements for periodontally lost lower incisors. METHODS: Besides the longevity of the restoration, the periodontal condition of the abutment teeth, and the general satisfaction of the patient were evaluated retrospectively via a phone interview, in combination with an analysis of the patient's clinical dental file. RESULTS: The cumulative proportion of survival rate of these composite restorations was 80% after 5 years of function. No statistically significant difference was found between the survival distribution of one- and two-pontic bridges (P = 0.66). The abutment teeth demonstrated stable probing depths and a negligible loss in attachment (0.1 mm/year). The satisfaction ratings were also favorable. CONCLUSIONS: The data seem to suggest that composite bonding of 1 or 2 teeth can be considered a semi-permanent rehabilitation for the replacement of 1 or 2 periodontally lost lower incisors.

Adult↗
PubMed1998

Oral stereognosis: a review of the literature.

Stereognosis is the ability to recognise and discriminate forms. Oral stereognostic ability has been studied in different reports. The experimental design of the test is of primary importance as both the method used and the material applied may influence the results dramatically. The form, size and surface characteristics of the test piece, the presentation order, subject-related factors and the method of scoring all have their effect on the results. With regard to subject-related factors, ageing has a negative influence on stereognostic ability; gender is considered of no importance. Another influencing factor is dental status. A healthy natural dentition offers a very good oral stereognostic ability. Edentulous subjects usually show a decreased oral stereognostic ability, depending on the rehabilitation form. A number of questions have been addressed, especially with regard to the perception itself. Receptors mainly involved in oral stereognostic ability are located in various oral structures and form perception results from an association of more than one group of receptors. The following review tries to deal with these questions and attempts to provide clear guidelines for further research on oral stereognosis.

Humans↗
PubMed1998

Rigidly splinted implants in the resorbed maxilla to retain a hinging overdenture: a series of clinical reports for up to 4 years.

STATEMENT OF PROBLEM: The results of the implant overdenture treatment in the maxilla remains inferior to those in the mandible. Different reasons have been alluded to, such as bone quality and quantity, number of implants, as well as the prosthesis design. PURPOSE: To investigate the latter, a new design for the rehabilitation of the resorbed maxillae was set up. MATERIAL AND METHODS: Thirteen patients were selected and provided with four endosseous maxillary implants, splinted with a rigid-cast bar. RESULTS: After a mean loading time of 3 years, six implants were lost; three at abutment and another three shortly after abutment connection, resulting in a cumulative success rate of 88.6% at year 4. A mean marginal bone loss of 0.3 mm was observed within the first year. After the first year, the marginal bone level, the attachment level, and the Periotest scores hardly changed. The main prosthetic complication was the frequent need to renew or to activate the attachments. A strong improvement in patient satisfaction was observed when compared with the old conventional denture. CONCLUSIONS: Within the limits of this study, the outcome confirmed that, on a medium-term base, implant-retained hinging overdentures on four implants were promising.

Adult↗
PubMed1998

An image-guided planning system for endosseous oral implants.

A preoperative planning system for oral implant surgery was developed which takes as input computed tomographies (CT's) of the jaws. Two-dimensional (2-D) reslices of these axial CT slices orthogonal to a curve following the jaw arch are computed and shown together with three-dimensional (3-D) surface rendered models of the bone and computer-aided design (CAD)-like implant models. A technique is developed for scanning and visualizing an eventual existing removable prosthesis together with the bone structures. Evaluation of the planning done with the system shows a difference between 2-D and 3-D planning methods. Validation studies measure the benefits of the 3-D approach by comparing plans made in 2-D mode only with those further adjusted using the full 3-D visualization capabilities of the system. The benefits of a 3-D approach are then evident where a prosthesis is involved in the planning. For the majority of the patients, clinically important adjustments and optimizations to the 2-D plans are made once the 3-D visualization is enabled, effectively resulting in a better plan. The alterations are related to bone quality and quantity (p < 0.05), biomechanics (p < 0.005), and esthetics (p < 0.005), and are so obvious that the 3-D plan stands out clearly (p < 0.005). The improvements often avoid complications such as mandibular nerve damage, sinus perforations, fenestrations, or dehiscences.

Dental Implantation, Endosseous↗
PubMed1998

The use of locally delivered minocycline in the treatment of chronic periodontitis. A review of the literature.

Tetracyclines are frequently used in the treatment of periodontitis; however, emergence of resistant bacterial strains has decreased the utility of these drugs. At present, there are a lot of data in the literature from which one can draw conclusions regarding the use of local drug delivery. This paper reviews the utility and different systems of local delivery of minocycline, a semisynthetic tetracycline, in the treatment of periodontitis.

Administration, Topical↗
PubMed1998

The effect of a 1-stage full-mouth disinfection on oral malodor and microbial colonization of the tongue in periodontitis. A pilot study.

Oral malodor affects a large proportion of the population and may be the cause of a significant social and psychological handicap. This pilot study aimed to examine whether a 1-stage full-mouth disinfection in periodontitis patients (scaling and root planing of all pockets within 24 hours together with the application of chlorhexidine to all intra-oral niches followed by chlorhexidine mouth rinsing for 2 months) resulted in a significant improvement in malodor when compared to a fractionated periodontal therapy (consecutive root planings per quadrant, at a 1 to 2 week interval). The baseline and outcome data concerning oral malodor were linked to the presence of tongue coating and to its roughness (fissures). Twenty-four patients with severe periodontitis were randomly allocated to test and control groups. At baseline and after 1 and 2 months, the concentration of volatile sulfur compounds (VSC) in the mouth was measured and organoleptic ratings (expired air and total mouth air) were given. Plaque samples were collected from the dorsum of the tongue to calculate the number of colony forming units (CFU) per ml (anaerobic culturing) as well as the number of pigmented CFU/ml. Both the baseline organoleptic ratings and the VSC scores correlated well with the presence of tongue coating but not with the tongue roughness. Because a correlation between tongue coating and its microbial load could not be detected, it was hypothesized that the tongue coating per se, and not the bacteria, might be responsible for the malodor. The 1-stage full-mouth disinfection resulted in a faster and additional reduction in the organoleptic ratings of the oral malodor, even after 2 months. This might be explained by the improved periodontal outcome and/or the more significant reduction in the CFU/ml of pigmented species. In contrast to the organoleptic ratings, which were significantly reduced in both treatment groups (when compared to baseline), the VSC levels remained unchanged. This pilot study indicates that a 1-stage full-mouth disinfection has, in comparison to a standard periodontal therapy, additional beneficial effects in the treatment of oral malodor.

Adult↗
PubMed1997

A randomised clinical trial on the influence of splinted and unsplinted oral implants in mandibular overdenture therapy. A 3-year report.

A randomised clinical trial was performed to investigate whether there is a need or advantage to splint two implants in the mandible retaining a hinging overdenture. Furthermore, patient satisfaction was evaluated for different attachment systems retaining the overdenture. Thirty-six edentulous patients were randomised into three groups of equal size and treated with either magnets, ball attachments or straight bars (reference group). After 3 years of observation no implants were lost in any of the groups. Besides, no statistically significant differences were noted for the peri-implant outcome. Although the bar group presented the highest retention force, the general satisfaction of the patients in the three groups did not differ. The patients with bar retentions showed less prosthetic complications of the retention elements but more at the level of the denture-supporting mucosa. Finally, the clinical outcome of all groups confirms that overdenture treatment demands regular controls with limited time intervals.

Adult↗
PubMed1997

The stereognostic ability of natural dentitions versus implant-supported fixed prostheses or overdentures.

A stereognostic ability test was performed in 60 patients. Forty patients were rehabilitated by means of osseointegrated implants. One group consisted of 20 patients with fixed prostheses on implants in both the upper and lower jaws. The other 20 patients had a maxillary denture while in the mandible an overdenture was retained by means of two implants connected by a bar. They were compared to a group of 20 subjects (controls) with a non-restored natural dentition. For the stereognostic ability test, subjects had to recognise ten different test pieces by manipulating them with two antagonistic incisor teeth, avoiding any contact with other oral structures. Both response time and percentage accuracy of recognition were evaluated. The present findings indicated that subjects with an overdenture on implants did not score significantly different from those with an implant-supported fixed prosthesis. In contrast, subjects with teeth had a significantly better stereognostic ability. The percentage of correct responses was 52% for overdentures, 56% for fixed prostheses on implants and 75% for natural dentitions. From these results, it could be concluded that the stereognostic ability is impaired in subjects rehabilitated with osseointegrated implants by about one-third to one-quarter compared to subjects with natural teeth.

Adult↗
PubMed1997

The rehabilitation of the severely resorbed maxilla by simultaneous placement of autogenous bone grafts and implants: a 10-year evaluation.

The long-term success of Brånemark implants has been previously reported. The success rate of the same implants, when associated with autologous grafts, seemed much less predictable. In the present study it is demonstrated that when these implants are installed in conjunction with an autologous corticocancellous hip graft, either onlay or inlay, the cumulative success rate remains at 95% for individual implants in non-smokers. The short extracorporal time might be an explanation. On the other hand, the same approach in patients with congenital defects or who underwent radiotherapy is deceptive. The use of hyperbaric oxygen may dramatically improve these results.

Adult↗
PubMed1997

The reliability of implant-retained hinging overdentures for the fully edentulous mandible. An up to 9-year longitudinal study.

The treatment of fully edentulous mandibles by means of implant-supported hinging overdentures has become a routine therapy, although long-term data on the success rate of implants and prostheses are lacking. This longitudinal study examined 207 consecutively treated patients who received, during the past 10 years, 449 Brånemark implants to retain a mandibular hinging overdenture, mainly on a Dolder bar. Clinical parameters and standardized radiographs taken at every recall visit with an interval of 6-12 months were used to judge the implant rigidity in the jawbone, the marginal bone level, and attachment level changes. The cumulative implant failure rate at 9 years was 3%. After loading, implant loss was concentrated during the first 12 months, with only one failure observed at 22 months. A radiographically determined bone loss of 0.7 mm was observed during the first year. From the second year, a mean annual bone loss of 0.05 mm occurred. The attachment loss, calculated as the sum of probing pocket depth plus the recession, was 0.07 mm/year and paralleled the changes in marginal bone level over time. The rigidity of the implant-bone interface revealed an increase over time, as shown by a decrease in Periotest values. The bar-overdenture complications were related to relining (23%), untightening of the retention clip (10%), and renewal of the prosthesis (7%). When magnets or ball attachments were used, more aftercare was needed. Fracture of the antagonistic full denture occurred in 7% of patients. The present data indicate that the mandibular overdenture therapy on two (Brånemark) implants is a very reliable and cost-effective treatment, even in a long-term perspective for the fixed full mandibular prosthesis and especially in elderly patients.

Adult↗
PubMed1997

Control of a trackball by the chin for communication applications, with and without neck movements.

The overall aim was to evaluate whether a trackball could be used for communication by people who cannot speak due to severe motor impairment. The precision of trackball control by isolated jaw movements or a combination of jaw and head movements was evaluated in 18 healthy physical-education students, free of overt symptoms of craniomandibular dysfunction. The participants were asked to operate a trackball using the chin to type a standard text of four short sentences. There were two experimental situations: nine participants performed the typewriting task with their heads fixed; the other nine performed this task with free head movements. Trackball operation moved to the cursor over an alphabetical keyboard displayed on a computer screen and character selection was made by depression of the left-hand click button using the chin. Participants were asked to perform the task as quickly and accurately as possible. Result showed that those with free head movement typed the test significantly faster than those restricted to using only their jaw muscles. The mean time per character selection was 2.4 s (SD 0.3) for the group with free head movement and 2.7 s (SD 0.3) for the group using only jaw muscles. Group scores were not significantly different with regard to accuracy. It is suggested that a chin-operated trackball could be used for communication applications both with and without neck movements.

Adult↗
PubMed1997

Complete nose coverage to prevent airborne contamination via nostrils is unnecessary.

Besides an atraumatic procedure, aseptic techniques during surgery have been suggested to have a positive impact on the predictability of osseointegration. To avoid an infection of the surgical field, coverage of the face of the patient (drapes) and nose (surgical mask, drape and plastic film) were advocated in order to reduce airborne infections and to prevent a contact contamination of instruments and gloves. Such a coverage, however, increases the feeling of claustrophobia when local anaesthesia is used and can lead to hypoxemia. The aim of the present study was to investigate whether the expired air via the nostrils could contribute to the contamination of the oral surgical field. Test blood agar plates were installed for 30 min under the nose of volunteers lying on a surgical table; once with full coverage of their nostrils, as indicated above, and once without. Simultaneously, control plates were installed on a table besides the patient to measure the basic contamination from the environment. All plates were incubated both aerobically and anaerobically. The number of colony forming units (c.f.u.) recorded on test plates after aerobic and anaerobic incubation were surprisingly low, with a mean score of 2.7 and 5.0 c.f.u. for the uncovered situation, and 2.5 and 3.3 c.f.u. for the covered situation, respectively. The control plates were infected by a nearly comparable number of bacteria (means ranging from 2.2 to 3.2). These findings indicate that covering nostrils by a mask and sterile adhesive plastic film is not essential in avoiding airborne microbial contamination. However, the use of a meshed nose guard to prevent contact with the highly contaminated nasal skin is highly recommended.

Adult↗
PubMed1997

Outcomes and their measurement in clinical trials of endosseous oral implants.

The clinical suitability of an oral implant system should be substantiated by well-planned clinical trials that meet the expectations of both the patient and the clinician; i.e., to offer anchorage to a dental prosthesis for one or more decades. The literature often reports on the survival rather than on the success rate, and for the latter a large variety of more or less stringent criteria have been proposed. Although the use of cumulative percentages to assess survival or success on consecutive patients, the so-called Kaplan-Meier statistics, is essential, many publications only report on absolute percentages, thus giving much too optimistic results. Indeed, the large number of recently inserted implants tend to dilute the small fraction that has gone through the maximum observation period. Multi-center studies on consecutive patients who are not selected on the basis of bone quality and volume should be recommended. Otherwise the labeling of the implant should clearly mention which groups; e.g., smokers or patients with limited bone volume are not part of the validated target group. The final outcome measurement would be that an endosseous implant is no longer able to carry out its purpose: to anchor or support successfully a functional dental prosthesis. Like many other clinical evaluations, surrogate parameters have been sought to assess interim success rates. The stability of the marginal bone level is one parameter proposed by many, although bone loss as such is not synonymous with failure. Several implant systems with a roughened surface (plasma sprayed or coated) suffer from progressive marginal bone loss and consequently ongoing loss of implants even after 5 or more years. Those implant systems should be evaluated with cumulative success rates over a period of 10 years. Only those that demonstrated a clustering of both bone and implant loss during the first 1 or 2 years after insertion and subsequently a levelling off for those two parameters-a so-called plateau pattern, should be allowed to draw conclusions after 5 years. Since radiographs reveal only the approximal areas, measurement of the attachment level by means of probing towards a reference point on the abutment should also be performed annually. Intra-oral radiographs can only reveal absence of radiolucency at the bone-implant interface, but do not prove osseointegration. The use of an electronic device offers objective results and reveals even subclinical mobilities of endosseous implants. One can conclude that there is an urgent need for a consensus between health authorities, third parties, and the scientific community to define a set of universally-acceptable success criteria, to impose the use of cumulative success rates, and to ask for observation periods of 10 years for implants that do not demonstrate stable results after one or two years.

Clinical Trials as Topic↗
PubMed1997

The use of tetracycline-containing controlled-release fibers in the treatment of refractory periodontitis.

The purpose of this study was to evaluate the safety and clinical efficacy of controlled-release tetracycline-containing fibers in patients with refractory periodontitis versus the preceding classical treatment. One hundred twenty-one sites in 20 patients were followed from baseline to 6 months after fiber insertion. Each selected site was > or = 5 mm deep and bled on probing. All 20 patients had at least one site > or = 7 mm which bled on probing. Those pockets remained after intense and repeated conventional therapy (scaling and root planing and often surgery), often including the use of systemic antibiotics. This treatment period, the so-called control period, preceded the experimental period by at least 3 years, when the fibers were placed. Both treatments (in control and test period) were performed in the Department of Periodontology at the University Hospital in Leuven. At the start of the experimental period, all pockets > or = 5 mm were treated by the placement of fibers impregnated with 25% tetracycline. The fibers were removed after 10 days. Probing depth, clinical attachment level, gingival recession, and bleeding on probing were recorded at baseline, and at 1, 3, and 6 months following treatment. Analysis of data from all sites indicated that a significant decrease in probing depth and gain in attachment were present at all follow-up visits. The mean probing depth reduction for sites > or = 7 mm was 3.2 mm at month 6, with a gain in attachment of 2.7 mm, while this was -1.0 mm and -1.9 mm, respectively, during the preceding control period. The fraction of bleeding pockets was reduced from 77% to 27% and from 80% to 77% during the experimental and control periods, respectively. No significant adverse side-effects were observed, except for a transient redness at fiber removal in 2 sites. Fiber insertion appeared to be time-consuming even when the operator was familiarized with the procedure. The results of this study prove that tetracycline-impregnated fibers can reduce probing depth significantly for a period of 6 months in patients not responding to thorough and repeated classical periodontal treatment.

Administration, Topical↗
PubMed1997

Experiences of a Belgian multidisciplinary breath odour clinic.

Experiences of a Belgian multidisciplinary breath odour clinic. Oral malodour is a frequent problem, which can benefit from a multidisciplinary approach (periodontology, ENT, internal medicine, psychiatry). An objective measurement of the amount of volatile sulphur compounds in the patient is very useful and easy to perform. Tongue coating is the most frequent cause. Initial treatment strategy should focus on oral hygiene. In a few cases, tonsillectomy or endoscopic sinus surgery may be necessary.

Adolescent↗
PubMed1997

Breath malodor.

Breath odor research has recently received increasing attention from periodontologists. Because a large portion of the adult population suffers from gingivitis and eventually periodontitis, the etiologic factor in all cases at risk must be considered. The first patient visit should, therefore, systematically include examination of the paranasal cavities and throat to avoid unnecessary time loss and frustration. Metabolic diseases and imaginary malodor should also be considered. Not only the mere presence of a chairside volatile sulfide monitor but also of that of an ear, nose, and throat specialist and eventually a psychiatrist or psychologist who determines whether a breath odor clinic merits its denomination. Volatile sulfur components are an important cause of breath malodor but they are not the sole cause. This explains why organoleptic and gas chromatographic diagnosis scores better than a portable sulfide monitor. Other than etiologic therapy, masking can be achieved for a number of hours by toothpastes containing a combination of triclosan and zinc chloride.

Breath Tests↗