Cornelis de Putter

Early bacterial colonization and soft tissue health around zirconia and titanium abutments: an in vivo study in man

AIM To compare the early bacterial colonization and soft tissue health of mucosa adjacent to zirconia (ZrO(2)) and titanium (Ti) abutment surfaces in vivo. MATERIALS AND METHODS Twenty edentulous subjects received two endosseous mandibular implants. The implants were fitted with either a ZrO(2) or a Ti abutment (non-submerged implant placement, within-subject comparison, left-right randomization). Sulcular bacterial sampling and the assessment of probing pocket depth, recession and bleeding on probing were performed at 2 weeks and 3 months post-surgery. Wilcoxon matched-pairs, sign-rank tests were applied to test differences in the counts of seven marker bacteria and the clinical parameters that were associated with the ZrO(2) and Ti abutments, at the two observation time points. RESULTS ZrO(2) and Ti abutments harboured similar counts of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Peptostreptococcus micros, Fusobacterium nucleatum and Treponema denticola at 2 weeks and 3 months. Healthy clinical conditions were seen around both ZrO(2) and Ti abutments at all times, without significant differences in most clinical parameters of peri-implant soft tissue health. Mean probing depths around Ti abutments were slightly deeper than around ZrO(2) abutments after 3 months (2.2 SD 0.8 mm vs. 1.7 SD 0.7 mm, P=0.03). CONCLUSIONS No difference in health of the soft tissues adjacent to ZrO(2) and Ti abutment surfaces or in early bacterial colonization could be demonstrated, although somewhat shallower probing depths were observed around ZrO(2) abutments after 3 month.

Treatment outcome with implant-retained overdentures: Part I—Clinical findings and predictability of clinical treatment outcome

This nationwide study was conducted to clinically evaluate treatment with implant-retained overdentures when applied on a large scale and to determine to what degree treatment results could be predicted from patient and treatment characteristics at baseline. A total of 429 patients who had received implant overdenture treatment were clinically investigated by two dentists. Implant survival was high, especially for implants placed in the mandible. Results for the maxilla appeared far less promising. Complications that were observed predominantly concerned inflammation of the peri-implant tissues and poor oral hygiene. The quality of the overdentures, as assessed on three conventional prosthetic parameters, was generally good. Nevertheless, overdentures on oral implants appear to require considerable maintenance. No statistically significant correlation could be found between patient and treatment characteristics at baseline and the clinical treatment outcome. So, although treatment outcome with implant-retained overdentures appeared favorable, clinical results were not individually predictable.

Dental treatment needs in Dutch nursing homes offering integrated dental care

The purpose of this study was to determine the dental treatment needs of the residents in nursing homes (NHs) where integrated dental care has been offered without financial barriers. The dental status and surgical, prosthetic, restorative, and periodontal treatment needs were determined for 432 residents (average age 78.8 years) in three Dutch NHs. Although the subjects had no complaints, 72% had dental treatment needs. It was determined that treatment was necessary for 64% of the edentulous subjects (N = 316), 100% of the partially dentate subjects (N = 76), and 87% of the fully dentate subjects (N = 40). We concluded that when residents can no longer carry out oral hygiene independently, it is very difficult for them to maintain a level of oral health where their dental treatment needs have been met, especially for dentate residents.

Dentofacial characteristics of patients with hypodontia

This study aims to identify distinctive dentofacial characteristics of hypodontia patients. For this purpose, 189 young hypodontia patients (cases) were divided into subgroups, based on criteria from literature. Normalised differences between cases and controls were calculated for various parameters of dentofacial form. Subsequently, cluster analysis was applied to disclose subsets of hypodontia patients with distinctive dentofacial features. The ANB angle, interincisal angle and lower anterior face height were consistently significantly different amongst the subsets. Four clusters of patients with an increasing number of missing teeth and distinctive dentofacial characteristics could be identified. Patients in cluster 1 display a high-angle facial pattern. Patients in clusters 2 and 3 exhibit markable dentoalveolar characteristics (a relatively small and a large interincisal angle, respectively). Patients in cluster 4 exhibited notable sagittal–skeletal discriminative features predominantly because of a retrognathic maxilla. The smallest nasolabial angle and lower anterior face height were seen in this cluster. It is concluded that the anterior–posterior relationship between the jaws, the interincisal angle and the lower anterior face height are discriminative parameters of dentofacial form in hypodontia patients. Patients with hypodontia can be clustered in four groups, each with distinctive vertical–skeletal, dentoalveolar and sagittal–skeletal characteristics. This categorisation of patients with hypodontia into meaningful groups may be useful for treatment planning, interdisciplinary communication and as a means of identifying groups of patients that qualify for reimbursement of costs. Other dental factors should be appreciated as well during restorative clinical decision making in patients with hypodontia.

Bone Structure Changes in Iliac Crest Grafts Combined with Implants

BACKGROUND Remodeling of onlay grafts combined with implants to the mandible results in predictable changes in the grafts radiographic density. We studied the relationship between changes in radiographic density and trabecular structure during the first year after onlay grafting with simultaneous implant placement to the mandible. PURPOSE The aim of this study was to evaluate changes in bone structure after onlay grafting. MATERIALS AND METHODS Standardized extraoral radiographs were taken regularly of 16 mandibular sides. Bone structure was measured using the Carl Zeiss Vision KS 400 3.0 imaging system. The parameters studied were trabecular area and perimeter, cavity area and perimeter, end points, branching points, skeleton length, branch angle and direction, and texture. RESULTS No differences were found between measurements ventrally versus dorsally of the implant, nor close to versus away from the implant. Early cortical changes suggest partial resorption and formation of a more complex structure. In the fourth quarter after surgery, progressive resorption is seen in the grafts upper cortex. In the grafts upper spongiosa, most parameters indicate bone formation during the first postoperative year. Loading-induced structure changes could not yet be found. CONCLUSION The technique can be used to study changes in the architecture of bone grafts. Changes found in the grafts architecture are in accordance with changes in bone density.

Effects of integrated dental care on oral treatment needs in residents of nursing homes older than 70 years

AIM To determine effects of integrated dental care in older nursing home residents. METHODS In three nursing homes offering integrated dental care, we studied the oral treatment need of 355 residents older than 70 years. To determine effects of integrated care, we discriminated between short-stay residents (≤6 months) and long-term residents (>6 months). RESULTS Treatment need, determined intraorally by two dentists, remains high among short-stay residents (78%) and long-term residents (67%). The association between treatment need and length of stay was not significantly affected by indication for stay (somatic vs. psychogeriatric). All dentate residents needed oral treatment, except one long-term resident. However, among edentulous residents, particularly with a psychogeriatric indication for stay, treatment need appeared to reduce significantly in time, from 74% to 57%. CONCLUSION Despite integrated dental care, oral treatment need remains in virtually all dentate residents and more than half of edentulous residents.

The association of clinical and microbiologic parameters with histologic observations in relatively healthy peri-implant conditions- a preliminary short-term in vivo study

PURPOSE To determine whether clinical findings-bleeding on probing, pocket depth, recession, and bacterial sampling-correlate with histologic outcomes in relatively healthy peri-implant soft tissues in people. MATERIALS AND METHODS In this cross-sectional study, a convenience sample of 20 edentulous subjects received two endosseous mandibular implants each. The abutments were either zirconia (ZrO₂) or titanium (Ti) (nonsubmerged implant placement, within-subject comparison, leftright randomization). Sulcular bacterial sampling and assessment of probing pocket depth, recession, and bleeding on probing were performed 3 months postsurgery. Mucosal biopsy specimens were obtained, and the blood vessel density and a score on an inflammation grading scale were determined. RESULTS Simple linear and linear regression models revealed that the clinical or microbiologic parameters were not associated with either of the histologic parameters. The soft tissues impressed as healthy, regardless of the abutment material. CONCLUSIONS The peri-implant mucosa around ZrO₂and Ti abutments was considered healthy in most situations when examined histologically after 3 months but showed variation in clinical and microbiologic parameters.

Early bacterial colonization and soft tissue health around zirconia and titanium abutments: an in vivo study in man: Bacterial colonization and soft tissue health around zirconia and titanium

AIM To compare the early bacterial colonization and soft tissue health of mucosa adjacent to zirconia (ZrO(2)) and titanium (Ti) abutment surfaces in vivo. MATERIALS AND METHODS Twenty edentulous subjects received two endosseous mandibular implants. The implants were fitted with either a ZrO(2) or a Ti abutment (non-submerged implant placement, within-subject comparison, left-right randomization). Sulcular bacterial sampling and the assessment of probing pocket depth, recession and bleeding on probing were performed at 2 weeks and 3 months post-surgery. Wilcoxon matched-pairs, sign-rank tests were applied to test differences in the counts of seven marker bacteria and the clinical parameters that were associated with the ZrO(2) and Ti abutments, at the two observation time points. RESULTS ZrO(2) and Ti abutments harboured similar counts of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Peptostreptococcus micros, Fusobacterium nucleatum and Treponema denticola at 2 weeks and 3 months. Healthy clinical conditions were seen around both ZrO(2) and Ti abutments at all times, without significant differences in most clinical parameters of peri-implant soft tissue health. Mean probing depths around Ti abutments were slightly deeper than around ZrO(2) abutments after 3 months (2.2 SD 0.8 mm vs. 1.7 SD 0.7 mm, P=0.03). CONCLUSIONS No difference in health of the soft tissues adjacent to ZrO(2) and Ti abutment surfaces or in early bacterial colonization could be demonstrated, although somewhat shallower probing depths were observed around ZrO(2) abutments after 3 month.