The rehabilitation of oral defects by osseointegrated implants.

So far, preprosthetic surgery for oral defects improved prosthetic retention problems for only a limited amount of time and led to many side-effects. The alternative offered by the osseointegration technique developed by P.-I.

Histo-pathologic characteristics of peri-implant soft tissues in Brånemark implants with 2 distinct clinical and radiological patterns.

This investigation is the result of a multicenter research project between the Catholic University of Leuven and the University of Madrid with the purpose of studying histometrically and ultrastructurally periimplant marginal tissue reactions in mendium-term Brånemark implants. 12 patients were selected and distributed according to predefined clinical and radiological parameters into a periimplant infection group (A) and a non-periimplant infection group (B). Biopsies were taken from these patients and analyzed by means of microscopy (LM), histometry (HM) and transmission electron microscopy (TEM).

Prosthetic aspects of osseointegrated fixtures supporting overdentures. A 4-year report.

Eighty-six consecutive patients, provided with 84 resilient and two nonresilient overdentures (six in the upper and 80 in the lower jaw), were examined. The overdentures were supported by a total of 173 osseointegrated titanium fixtures (the standard Branemark abutment), with a mean loading time of 19.1 months (range 4 to 48 months).

Masseteric post-stimulus EMG complex following mechanical stimulation of osseointegrated oral implants.

Periodontal receptors can be located in the periodontal ligament itself, the alveolar bone, the periosteum and the gingiva. The aim of the present study was to quantify the contribution of the periodontal ligament receptors in eliciting a reflex response in human masseter muscles. Surface EMG recordings were made in 17 human subjects, fully or partially edentulous, and all provided with osseointegrated oral implants ad modum Brånemark.

Comparative evaluation of the oral tactile function by means of teeth or implant-supported prostheses.

To clarify more of the tactile function of oral implants, both an interocclusal thickness detection and discrimination task were carried out in 4 different test conditions on 37 patients: t (tooth)/t, i (implant)/t, i/i and d (denture)/o (overdenture supported by implants). For the interocclusal detection of steel foils, the 50% detection threshold level (RL) in the 4 conditions was 20, 48, 64 and 108 microns, respectively, which indicates significant differences. The ability to discriminate interdental thickness differences was tested with a 0.

Oral implants.

Today, more and more evidence suggests that even small changes in hardware for oral implants may jeopardize its biocompatibility. Even the manner in which the hardware is sterilized can influence cellular adhesion. This review discusses the surface characteristics, configuration, and success rates of various oral implants, as well as the complications that can result following implantation.

The influence of gingival inflammation, tooth type, and timing on the rate of plaque formation.

The undisturbed supragingival plaque formation was recorded twice over a 100 hours period in 14 healthy dental students; first after induction of gingival inflammation and a second time starting from a healthy gingiva. During each experimental segment plaque formation was recorded on 42 randomly selected and clean teeth at the start and after 6, 12, 24, 30, 36, 48, 54, 60, 72, 84, and 96 hours. Four hours later all teeth up to the first molars were examined.

Discriminating power of five plaque indices.

Since plaque plays a major role in the development of periodontal inflammation, special attention is paid to its composition and quantity. Several indices have been designed for the quantification of the supragingival plaque. The aim of the present study was to compare the utility and discriminating power of five such plaque indices.

Periotest: an objective clinical diagnosis of bone apposition toward implants.

Implant mobility as an indicator of failing close bone apposition is generally known. Whereas a clearly visible mobility can always be correlated with an interposition of soft tissue, the range from a clinically firm implant to just tangible implant mobility represents the actual problem zone. Thirty consecutive patients who had mandibles restored with osseointegrated implants ad modum Brånemark were tested with the Periotest device for damping characteristics of the implants and the peri-implant tissues as a whole.

The precision of motor control in human jaw and limb muscles during isometric contraction in the presence of visual feedback.

Experiments showed that the human capacity to maintain a particular isometric force in the presence of visual feedback during a force-level, pursuit-tracking experiment is less developed for the jaw-closing muscles than for the limb muscles. This finding may indicate that the projection on the trigeminal motoneurone pool from visual inputs is poor, or that the trigeminal effector system itself is less finely tuned.

Computed tomography in the preoperative planning of oral endo-osseous implant surgery.

Computed tomography (CT) is a well-established aid in the preoperative assessment of the dimension of mandible and maxilla for endo-osseous implant installation. CT is a valuable tool for the measurement of the alveolar ridge and recognition of the course of the inferior alveolar nerve canal. In the present study, three different techniques were examined: normal CT images with coronal and sagittal slices, standard reconstructions based on axial slices, and multiplanar reconstruction and display (MPR/MPD), also based on axial slices.

[The implant/tissue interface in a clinical perspective].

For a proper insight in the implant/tissue interface of permucosal oral implants it is good to refer to the tooth/periodontium interface. Although there are evident differences such as the lack of a periodontal ligament with its possibilities for eruption and migration and elaborate neural endings, it seems that classical periodontal parameters are the yardstick to discriminate failure from success of oral implants. Long cone radiographs and mobility assessment seem the only available clinical tools to detect a scar tissue interposition.

Comparative antiplaque activity of sanguinarine and chlorhexidine in man.

This clinical investigation examined the effect of a sanguinarine extract on bacterial plaque growth in man. Three different mouthrinses were examined: (i) Veadent containing 0.03% sanguinarine and 0.

The influence of surface free energy and surface roughness on early plaque formation. An in vivo study in man.

Previous in vivo studies suggested that a high substratum surface free energy (s.f.e.

[Osseointegrated implants ad modum Brånemark in the oral rehabilitation of patients with advanced periodontal breakdown].

Despite the achievements of modern periodontology, partially or completely edentulous mouths are unavoidable. The rehabilitation of such patients is a great challenge in oral health care. The state of the art of osseointegrated implants according to Brånemark is described.

Applicability of osseointegrated oral implants in the rehabilitation of partial edentulism: a prospective multicenter study on 558 fixtures.

Nine clinical centers using the Brånemark System participated in a prospective study of 159 partially edentulous patients between 18 and 70 years of age. Clinical parameters evaluated were plaque index, gingivitis, pocket depth, bleeding index, tooth mobility, and stomatognathic function. Initially, 558 fixtures were placed and 521 remained in the study following prosthesis placement (199 prostheses in 154 patients).

CT scan standard reconstruction technique for reliable jaw bone volume determination.

Computed tomography can assist the surgeon in planning the exact three-dimensional positioning of endosseous implants in the jaw bone. This study examined the reliability of three CT techniques: direct imaging (normal coronal and sagittal slices), standard reconstruction (based on axial slices), and multiplanar reconstruction and display (also based on axial slices). The three imaging techniques were used to estimate the bone height, bone width, and maximal implant length in six dissected human jaw bones.

Comments on standardization of reflex measurements in human masseter muscle, including silent periods.

The following comments are given on the guidelines suggested by Türker (1988) for studies on oral reflexes using the surface EMG of the masseter muscles in man, including the silent period. (i) Attention should not be confined to electrical stimulation since mechanoreceptors in the periodontium, especially in the periodontal ligament, can only be activated by mechanical stimulation of a tooth. Furthermore, different modes of stimulation and stimulation sites do not yield equivalent reflex complexes.

Is early plaque growth rate constant with time?

Early plaque growth and plaque topography were studied in 15 young adults with a healthy periodontium during a 4-day period of no oral hygiene. After perfect tooth-cleaning, the recolonisation of the buccal surfaces of 48 teeth (front teeth and premolars) was recorded at the start and after 6, 12, 24, 30, 36, 48, 54, 60, 72, 84 and 96 h. At each visit, reproducible colour slides of the buccal tooth surfaces were taken after plaque disclosure.

The influence of surface free-energy on planimetric plaque growth in man.

The purpose of this study was to examine the change in plaque area over nine days in vivo on four materials with different surface free-energies (s.f.e.

A retrospective multicenter evaluation of the survival rate of osseointegrated fixtures supporting fixed partial prostheses in the treatment of partial edentulism.

Whether the excellent prognosis of the osseointegration technique also applies for the rehabilitation of partially edentulous jaws was investigated through a multicenter retrospective study. Six centers from three continents participated in the study, which included 133 fixtures in 38 patients. Forty fixtures were installed in the upper jaw and 93 in the lower jaw.

Single motor unit and surface electromyogram analysis of human jaw-closing muscle reflexes after tapping an upper tooth.

The mechanical stimulation of an upper tooth elicited reflex responses in masseter and temporalis motor units, which were recorded with both surface and needle electromyograms (EMGs) simultaneously. The subjects maintained one of the recorded motor units, which was the latest recruited unit, at a constant firing frequency, varying from 12 to 25 Hz. After a latency of 10 ms, all 19 motor units were inhibited for a period, the duration of which depended on the prestimulus firing frequency.

[Surgical and non-surgical approach to deep periodontal pockets].

Deepened pockets are a challenge because they offer an anaerobic niche and because of their inaccessibility to personal plaque control measures. Scaling and root planing followed by regular professional plaque removal are effective in arresting the progress of most chronic adult periodontitis. Only when pockets remain inflamed after repeated thorough professional treatment during several months can a surgical pocket elimination technique be used.

Periodontal aspects of osseointegrated oral implants modum Brånemark.

The osseointegration method developed by Brånemark offers new perspectives in the rehabilitation of partial and total edentulism in cooperation with the prosthodontist or general practitioner. The success rates over 90 and even 95 per cent in the upper and lower jaws, respectively, have been confirmed by several teams on series of consecutive patients. Ongoing research will allow discrimination between those systems that really osseointegrate predictably and those that do this irregularly or only demonstrate a close bone apposition.

Interactive periodontal and acoustic influences on the masseteric post-stimulus electromyographic complex in man.

Post-stimulus electromyogram (EMG) complexes (PSECs) were studied in the full-wave rectified and averaged EMGs of the masseter muscles in 15 subjects, who clenched at a controlled level. The PSECs, a series of downward- and upward-going waves reflecting inhibitory and excitatory influences upon the masseteric motoneurones, were elicited by mechanical stimulation of a tooth. The stimuli selectively activated mechanoreceptors in the periodontium and, by bone-conduction, acoustic receptors.