Single implant-supported two-unit cantilever fixed partial dentures in the posterior region: a retrospective case series with a mean follow-up of 6.5 years.

BACKGROUND: The aim of this retrospective study was to evaluate the implant survival, clinical and radiographic outcomes, and patient satisfaction of single implant-supported two-unit cantilever fixed partial dentures in the posterior region. METHODS: Patients who received a single implant-supported fixed partial denture with a cantilever in the posterior region between January 2004 and February 2018 were included. Survival rate of the implants and the fixed partial dentures and data regarding the marginal bone level, presence of plaque, calculus, bleeding on probing, mucosa health, pocket probing depth, and patient satisfaction were collected during an evaluation visit. Complications were recorded from the medical records. RESULTS: Twenty-three patients (mean age 64 ± 13 years) with 28 implants could be included in the study. The mean follow-up period was 6.5 ± 4.8 years at the time of data collection. The survival rate of the implants and fixed partial dentures was 100%. Mean marginal bone loss for the mesial and distal side of the implants was 0.41 mm (SD 1.18 mm) and 0.63 mm (SD 0.98 mm) respectively. A high prevalence of peri-implant-mucositis (89.3%) and peri-implantitis (17.9%) was observed as well as a limited number of technical complications. Patients were quite satisfied, as reflected by a mean VAS score of 94.0 ± 7.2 points (range 0-100) and a OHIP-NL49 score of 10.8 (range 0-196). CONCLUSIONS: Single implant-supported fixed partial dentures with a mesial or distal cantilever can be a predictable treatment option in the posterior region, with stable peri-implant bone levels, minor technical complications, and very content patients. However, the prevalence of peri-implant mucositis and peri-implantitis was high. TRIAL REGISTRATION: ISRCTN, ISRCTN79055740 , Registered on March 14, 2021 - -Retrospectively registered.

Performance of ceramic laminate veneers with immediate dentine sealing: An 11 year prospective clinical trial.

OBJECTIVE: In this prospective clinical trial the survival, success rate and patient satisfaction of ceramic laminate veneers with special interest on existing restorations, immediate dentin sealing and endodontically treated teeth was evaluated. METHODS: A total of 104 patients (mean age: 42.1 years old) received 384 feldspathic ceramic laminate veneers on maxillary anterior teeth. Veneer preparations with incisal overlap were performed using a mock up technique. Existing resin composite restorations of acceptable quality were not removed but conditioned using silica coating and silanization. Immediate dentin sealing (IDS) was applied when more than 50% of dentin was exposed during preparation. Endodontically treated teeth were not excluded. After adhesive cementation, restorations were evaluated by calibrated evaluators at baseline and final follow-up using modified USPHS criteria. RESULTS: 225 Laminate veneers were bonded onto teeth without existing restorations, 159 on teeth with pre-existing resin composite restorations, 87 to teeth with more than 50% of exposed dentin surface and 43 to endodontically-treated teeth. In total, 19 failures were observed in form of debonding (n = 3), fracture (n = 15) and extraction due to endodontic complications (n = 1). In teeth with more than 50% of dentin exposure, a significant increase in survival rate was observed when IDS was used (96.4% versus 81.8%). No significant difference was found between teeth with and without pre-existing composite resin restorations (84.6% versus 95.5%) or between vital and non-vital teeth (95.6% versus 88.1%). Laminate veneers luted to endontically-treated teeth had a significant mis-match in color compared to vital teeth. Patients who smoked presented with significantly more marginal discoloration, but no intervention was needed. Patients scored favorably values on the Oral Health Impact Profile questionnaire and were generally satisfied with the treatment. In this clinical trial, the ceramic laminate veneers had a relatively high survival rate. SIGNIFICANCE: Teeth with more than 50% of dentin exposure significantly benefit from IDS. Pre-existing restorations or endodontic treatments do not have an effect on the survival rate of ceramic laminate veneers. However, smoking habits and previous endodontic treatments negatively affect the success rate due to color changes. CLINICAL TRIAL REGISTRATION NUMBER: NCT03645551.

Dental implants with fixed prosthodontics in oligodontia: A retrospective cohort study with a follow-up of up to 25 years.

STATEMENT OF PROBLEM: Long-term assessments of implant survival and treatment outcome in patients with oligodontia are lacking. PURPOSE: The purpose of this retrospective clinical study was to assess which factors determine a long-term implant survival and treatment outcome of up to 25 years in a cohort of patients with oligodontia. MATERIAL AND METHODS: The medical records of all patients with oligodontia treated with fixed implant prosthodontics between January 1991 and December 2015 in the Department of Oral and Maxillofacial Surgery at the University Medical Center Groningen, the Netherlands, were assessed. Specifically, this involved the retrieval of records on the need for and mode of bone augmentation, implant survival, and survival of and adverse events associated with the prosthodontics. The Kaplan-Meier estimator was used to analyze implant and superstructure survival. Log-rank tests were used to compare the survival of subgroups. RESULTS: A total of 126 patients with oligodontia were treated with dental implants. Of the 777 implants in total, 56 were lost, resulting in a 5-year cumulative survival of 95.7% (95% confidence interval [CI], 94.2% to 97.2%) and a 10-year cumulative survival of 89.2% (95% CI, 86.2% to 92.2%). The survival of implants placed in regions where bone augmentation surgery had been performed was significantly lower. The 5-year cumulative superstructure survival was 90.5% (95% CI, 87.6% to 93.5%), and the 10-year cumulative superstructure survival was 80.3% (95% CI, 75.3% to 85.3%). The performance of the screw-retained and cemented superstructures was comparable, but the survival of single crowns was significantly higher than the survival of fixed partial dentures (P<.001). CONCLUSIONS: Implant treatment is a predictable treatment option for patients with oligodontia with a favorable long-term outcome. Survival of implants in augmented areas is lower.

Long-term implant performance and patients' satisfaction in oligodontia.

OBJECTIVES: To assess long-term (≥10 years) implant survival, peri-implant health, patients' satisfaction and oral health related quality of life (OHQoL) in oligodontia patients rehabilitated with implant-based fixed prosthodontics. METHODS: All oligodontia patients treated ≥10 years previously with implant-based fixed prosthodontics at the University Medical Center Groningen, The Netherlands, were approached to participate. Clinical (plaque index, bleeding index, pocket probing depth) and radiographic (marginal bone level) data were collected between February and May 2016. Surgical implant details (e.g., bone augmentation) and implant loss were recalled from the medical records. Patients completed a satisfaction questionnaire (maximum score 10, high score favourable satisfaction) and the Oral Health Impact Profile (OHIP-NL49, maximum score 196, low score favourable satisfaction) to rate OHQoL. Implant survival was expressed according to Kaplan Meier. The Mann-Whitney U Test was used for the other analyses. RESULTS: Forty-one patients had been treated with implant-based fixed prosthodontics (n = 258) ≥10 years previously. Cumulative 10-year implant survival of these 41 patients was 89.1% (95%CI 85.2-93.0%). Twenty-eight of them (n = 163 implants) were willing to visit us for additional clinical and radiographic assessments. In these 28 patients, highest peri-implant bone loss was observed for implants placed in augmented bone (p < 0.001). Peri-implant mucositis (65.4%) and peri-implantitis (16.1%) were rather common. Patients' satisfaction (8.3 ±â€¯1.5) and OHIP-NL49 scores (32.6 ±â€¯30.1) were favourable and not associated with number of agenetic teeth (≤10 versus >10). CONCLUSIONS: Long-term survival, satisfaction and OHQoL results reveal that implant treatment is a predictable and satisfactory treatment modality for oligodontia, although peri-implant mucositis and peri-implantitis are common. CLINICAL SIGNIFICANCE: This study showed unique long-term (≥10 years) results about implant survival, peri-implant health, patients' satisfaction and OHQoL in oligodontia patients rehabilitated with implant-based fixed prosthodontics.

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.

The effect of zirconia and titanium implant abutments on light reflection of the supporting soft tissues.

OBJECTIVES: To determine the difference in light reflection of oral mucosa covering titanium (Ti) or zirconia (ZrO(2)) abutments as it relates to the thickness of the covering mucosa. MATERIAL AND METHODS: Fifteen anterior implants (Astra Osseo speed(®)) in 11 patients were fitted with a Ti or a ZrO(2) abutment (cross-over, within-subject comparison). Hyper-spectral images were taken with a camera fitted on a surgical microscope. High-resolution images with 70 nm interval between 440 and 720 nm were obtained within 30 s (1392 × 1024 pixels). Black- and white-point reference was used for spatial and spectral normalization as well as correction for motion during exposure. Reflection spectra were extracted from the image on a line mid-buccal of the implant, starting 1 mm above the soft tissue continuing up to 3 mm apically. RESULTS: Median soft tissue height is 2.3 mm (min: 1.2 mm and max: 3.1 mm). The buccal mucosa rapidly increases in the thickness, when moving apically. At 2.2 mm, thickness is 3 mm. No perceivable difference between the Ti and ZrO(2) abutment can be observed when the thickness of the mucosa is 2±0.1 mm (95% confidence interval) or more. CONCLUSION: It is expected that the difference in light reflection of soft tissue covering Ti or ZrO(2) abutments is no longer noticeable for the human eye when the mucosa thickness exceeds 2 mm. Haemoglobin peaks in the reflection spectrum can be observed and make hyper-spectral imaging a practical and useful tool for measuring soft tissue health.

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.

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 graft's 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 graft's upper cortex. In the graft's 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 graft's architecture are in accordance with changes in bone density.

An unusual case of implant failure.

A 67-year-old woman was referred with a rapidly progressing swelling in the left canine region of the edentulous mandible. Nine months earlier, 2 permucosal implants had been placed in her atrophic anterior mandible. A few weeks after implant placement, an inoperable carcinoma of the lung had been diagnosed. This tumor was treated with a combination of chemotherapy and radiotherapy. After 3 months, the implants were provided with a Dolder bar supporting an overdenture. Subsequently, progressive inflammation developed around the left implant and removal of the implant was necessary. When progressive swelling of the mucosa developed at the previous implant site, the patient was referred to an oral and maxillofacial surgeon. The swelling measured 35 mm in diameter and was biopsied. It was diagnosed as a metastasis of the lung carcinoma to the mandible. The tumor of the jaw was treated with local radiotherapy.