Quintessence International, 5/2024
DOI: 10.3290/j.qi.b5213535, PubMed ID (PMID): 38619259Pages 360-371, Language: EnglishErcal, Pinar / Calciolari, Elena / Patel, Rajvi / Zou, Lifong / Mardas, Nikolaos / Donos, NikolaosObjective: This pilot study aimed to evaluate, for the first time, the changes in facial tissues following the placement of a single dental implant.
Method and materials: Patients were scanned with a 3D facial scanner (3dMD) before implant surgery, immediately after surgery (T1), at 7 days postoperatively (T2), and at the impression stage (T3). Acquired images were processed using the 3dMDvultus (3dMD) software program and volume differences and linear depth measurements were calculated to determine the morphometric changes over time. A total of 11 patients were included in the analyses. Descriptive statistics were employed to analyze the data.
Results: The volumetric changes and maximum depth differences indicated an initial increase, followed by a progressive decrease in tissue volume after implant placement in the area of the surgery. The volume change values ranged between 2.5 and 3.9 cm3 for T1, whereas for T2, the volume change decreased to a range of 0.8 to 1.8 cm3. Maximum depth differences ranged between 2.06 and 2.80 mm in the soft tissues immediately after the implant surgery and reduced to around 2.01 to 0.55 mm at the impression stage. The amount of painkiller used was not related to the magnitude of linear depth measurements at any assessed time point.
Conclusion: There was a longitudinal decrease in soft tissue volume and depth difference in extraoral soft tissues in the region of implant placement after surgery up to 6 weeks. The use of a facial scanner is a promising noninvasive method to monitor 3D morphometric changes after implant surgery.
Keywords: dental implants, facial scan, stereophotogrammetry
The International Journal of Oral & Maxillofacial Implants, 4/2019
DOI: 10.11607/jomi.7241, PubMed ID (PMID): 30768659Pages 873-885a, Language: EnglishPauletto, Patrícia / Ruales-Carrera, Edwin / Gonçalves, Thais Marques Simek Vega / Philippi, Analucia Gebler / Donos, Nikolaos / Mezzomo, Luis AndréPurpose: To evaluate, through a systematic review of the literature, the published data regarding marginal bone loss, implant failure proportion, biologic and prosthetic complications, and risk factors associated with short (≤ 8 mm) implants supporting fixed or removable full-arch restorations in the edentulous mandible.
Materials and Methods: Two reviewers performed a search of five databases, with handsearching through the reference lists and gray literature. Controlled clinical trials and prospective cohort studies were selected in a two-phase process. The data were independently gathered by the same two reviewers. Quality assessment of the studies was done using the Cochrane Handbook for Systematic Reviews of Interventions for Randomized Clinical Trials and the Newcastle-Ottawa Scale for Prospective Cohort Studies. Marginal bone loss and implant failure proportion were meta-analyzed using random and fixed-effects models, respectively, with 95% confidence intervals. A descriptive analysis was performed of the prevalence of biologic and prosthetic complications. Meta-regression analysis was run as fixed-effect models for risk factors.
Results: Six studies met the eligibility criteria and had data extracted. A total of 291 short implants (lengths 5 to 8 mm) were placed in 122 patients (82 women; mean age, 64.7 ± 10.8 years) supporting 23 fixed and 99 removable full-arch restorations. The pooled marginal bone loss overall was 0.12 mm (0.07 to 0.17 mm). Marginal bone loss for fixed full-arch restorations was 0.11 mm (0.01 to 0.21 mm) and for removable full-arch restorations was 0.14 mm (0.07 to 0.21 mm). The pooled overall implant failure proportion was 2.0% (1.0% to 5.0%) for the studies. Implant failure proportion for fixed and removable restorations was 2.0% with confidence intervals of 0.0% to 9% and 0.0% to 6%, respectively. The prevalence of prosthetic complications was 34.5% for fixed restorations and 2.6% for removable restorations. No biologic complications were found for fixed restorations, while 13.1% of removable restorations did have biologic complications. Risk factors did not demonstrate statistical differences regarding implant failure proportion and marginal bone loss. All included studies demonstrated a high methodologic quality.
Conclusion: Findings from this systematic review and meta-analysis suggest that full-arch restorations supported by short implants in atrophic edentulous mandibles might be a viable treatment option, presenting minimal marginal bone loss and implant failure in the short term. However, further well-performed prospective clinical trials with long-term observation are needed.
Keywords: edentulous patients, meta-analysis, short implants, systematic review
Quintessence International, 4/2015
DOI: 10.3290/j.qi.a33402, PubMed ID (PMID): 25642460Pages 287-298, Language: EnglishPrada-López, Isabel / Quintas, Víctor / Donos, Nikolaos / Suárez-Quintanilla, David / Tomás, InmaculadaObjective: To analyze the evolution of the thickness, bacterial vitality, covering grade, and the structure after 2 and 4 days of aging in "non-disturbed" plaque-like biofilm (PL-biofilm).
Method and Materials: Twenty healthy volunteers wore a specific appliance. After 2 days half of the samples were removed from the appliance. Posteriorly, after bacterial vital staining, samples were analyzed using a confocal laser scanning microscope. In the first volunteer, one of the disks was analyzed using a scanning electronic microscope. The same process was realized on the remaining disks after 4 days.
Results: The thicknesses of the PL-biofilm after 2 and 4 days were not significantly different. The bacterial vitality changed significantly from 72.50 ± 15.50% to 57.54 ± 15.66% over time, which was in contrast to the covering grade (53.08 ± 18.03% and 70.74 ± 19.11%). The structure changed from an irregular surface and compact deepest layer with a high predominance of the coccus shape to a complex structure with voids in the deepest layer and a great proportion of bacillus-shaped bacteria.
Conclusion: The PL-biofilm thickness remained practically constant, decreasing the bacterial vitality and increasing the covering grade over time. Regarding the structure, differences were principally bacterial disposition in the surface and bacterial shape. Clinically, the findings show that new control strategies for combating the oral biofilm should be focused on inhibiting bacterial adhesion to tooth surfaces, which would reduce biofilm formation.
Keywords: bacterial vitality, covering grade, laser scanning confocal microscopy, plaque-like biofilm, scanning electron microscopy, structure, thickness
Quintessence International, 10/2014
DOI: 10.3290/j.qi.a32511, PubMed ID (PMID): 25126630Pages 853-860, Language: EnglishFischer, Kai R. / Fickl, Stefan / Mardas, Nikos / Bozec, Laurent / Donos, NikolaosObjective: To present the application of two diff erent soft tissue grafts around dental implants during stage-two surgery. Furthermore, the ultrastructure of these materials is shown and discussed using scanning electron microscopy (SEM).
Summary: Although soft tissue autografts may be currently regarded as the gold standard, harvesting of these grafts might lead to higher morbidity, longer chair time, and intra-/postoperative complications at the donor site. New developments in collagen scaff olds have provided an alternative to successfully replace autologous grafts in clinical practice. The SEM pictures clearly show the diff erent composition of a bilayer scaff old (collagen matrix, CM) and a porcine acellular dermal matrix (ADM). These distinctive properties lead to different possible indications. Within the presented cases, ADM was used to augment the ridge contour and was placed into a buccal pouch to achieve complete coverage and an uneventful closed healing. On the other side, CM was left exposed to the oral cavity to successfully gain keratinized mucosa around and between two dental implants.
Keywords: acellular dermal matrix, bilayer collagen matrix, matrix structure, stage-two surgery, soft tissue augmentation
The International Journal of Oral & Maxillofacial Implants, 6/2012
PubMed ID (PMID): 23189285Pages 1359-1374, Language: EnglishVouros, Ioannis D. / Kalpidis, Christos D. R. / Horvath, Attila / Petrie, Aviva / Donos, NikolaosPurpose: The aim of the present systematic review was to address the following question: in patients treated with dental implants placed in pristine bone, what are the clinical and radiographic outcomes of bone-level (BL) implants in comparison to tissue-level (TL) implants after restoration with dental prostheses?
Materials and Methods: Scanning of online literature databases from 1966 to January 2012, supplemented by hand searching, was conducted to identify relevant prospective randomized controlled trials, controlled clinical trials, and cohort studies. Sequential screenings at the title, abstract, and full-text levels were performed independently and in duplicate. A meta-analysis was conducted to compile data from the primary studies included in this systematic review.
Results: The search strategy revealed a total of 5,998. Screening at the title level resulted in 752 papers, while screening at the abstract level yielded 92 publications. Full-text reading identified nine articles that fulfilled the inclusion criteria of this review. The pooled estimated difference between BL and TL implants in mean marginal bone loss was 0.05 mm (95% confidence interval [CI], -0.03 to 0.13 mm), with no statistically significant difference between the groups at 1 year after placement of the definitive prostheses. The relative risk of implant loss was estimated at 1.00 (95% CI, 0.99 to 1.02) at 1 year and at 1.01 (95% CI, 0.99 to 1.03) at 3 years after restoration, indicating no evidence of an increased risk of implant loss in BL compared to TL implants.
Conclusions: No statistically significant differences in bone loss and survival rates were detected between BL and TL dental implants over a short-term observation period (1 to 3 years). Thus, both implant systems fulfill the requirements for the replacement of missing teeth in implant dentistry.
Keywords: bone-level implants, bone loss, dental implants, implant outcomes, implant survival, systematic review, tissue-level implants
Quintessence International, 2/2012
PubMed ID (PMID): 22257874Pages 127-134, Language: EnglishFurze, David / Byrne, Ashley / Donos, Nikolaos / Mardas, NikosThe aim of this study was to evaluate the clinical and esthetic outcomes of 10 consecutive single-tooth implant restorations in the anterior maxilla. A specific treatment protocol consisting of (1) atraumatic extraction of the failing tooth, (2) placement of an SLActive bone-level implant with simultaneous guided bone regeneration at 6 to 8 weeks postextraction, (3) loading of a provisional restoration at 2 to 3 months following implant placement, (4) production of a customized impression coping, and (5) loading of the definitive all-ceramic abutment and crown 6 months after delivery of the provisional restoration was utilized in all cases. The outcomes were assessed 1 year after loading of the definitive restoration using standard clinical parameters: pink (PES) and white esthetic scores (WES). All implants were successfully integrated, accounting for a 100% survival and success rate. Besides clinical success, the application of the specific treatment protocol may be able to provide esthetically pleasing single-tooth implant restorations in the anterior maxilla, as was demonstrated by the results for PES (7.9 ± 1.7) and WES (7.0 ± 1.5).
Keywords: dental implants, esthetics, general dental practitioner
International Journal of Periodontics & Restorative Dentistry, 4/2004
Pages 363-369, Language: EnglishDonos, Nikolaos/Glavind, Leif/Karring, Thorkild/Sculean, AntonThe present study evaluated the effect of combining an enamel matrix derivative (EMD) and a bioresorbable membrane (GTR) in the surgical treatment of degree III mandibular furcation involvements. Nine patients with chronic periodontitis, presenting a total of 14 degree III mandibular furcation involvements, were included in the study. Surgical treatment of the defects was randomly assigned: (1) EMD (four defects); (2) GTR (three defects); and (3) EMD and GTR (seven defects). The degree of involvement was assessed prior to surgery and after 6 and 12 months by measuring the probing attachment level in the horizontal and vertical directions at the furcation site. At 6 and 12 months, partial closure of the involvements had occurred in approximately half of the treated furcations, and the vertical probing level consistently improved following all three treatment modalities. The results suggest that all three treatment modalities may improve healing following surgical treatment of degree III mandibular furcation involvements. However, further studies are needed to examine the clinical significance of these results and the histologic characteristics of the healing following application of EMD.
International Journal of Periodontics & Restorative Dentistry, 5/2003
Pages 507-512, Language: EnglishDonos, Nikolaos/Glavind, Leif/Karring, Thorkild/Sculean, AntonThe aim of the present study was to evaluate the clinical outcome following application of an enamel matrix derivative in degree II mandibular furcation involvements. Ten patients with chronic periodontitis, presenting a total of eight buccal and eight lingual degree II furcation involvements, were included in the study. The following clinical parameters were evaluated prior to treatment and after 6, 12, and 36 months: probing attachment level in horizontal direction in the buccal and/or lingual furcation area (PAL-H) and probing attachment level in vertical direction (PALV) at the center of the buccal/lingual furcation area. The postoperative healing phase was uneventful in all cases, and no complications were observed throughout the entire study period. At 6 months, the mean PAL-H of the buccal defects was reduced from 4.0 ± 1.3 mm to 2.6 ± 1.4 mm, and the mean PAL-V was reduced from 5.2 ± 2.0 mm to 4.0 ± 1.6 mm. At the lingual defects, the mean PAL-H was reduced from 3.6 ± 1.3 mm to 3.1 ± 1.1 mm, and the mean PAL-V was reduced from 5.6 ± 2.0 mm to 4.3 ± 1.8 mm. At 12 and 36 months, clinical parameters remained similar, without any further clinical improvement. These results suggest that the treatment of degree II mandibular furcation involvements with enamel matrix derivative might lead to clinical improvement. However, controlled clinical trials and histologic studies are needed to examine the clinical significance of these results and the characteristics of healing following application of enamel matrix derivative.
International Journal of Periodontics & Restorative Dentistry, 5/1999
Pages 501-509, Language: EnglishSculean, Anton / Donos, Nikolaos / Chiantella, Giovanni Carlo / Windisch, Péter / Reich, Elmar / Brecx, MichelThe aim of the present study was to evaluate clinically and histologically the treatment of intrabony periodontal defects with a bioresorbable membrane barrier. Fifty-two intrabony periodontal defects were treated according to the principles of guided tissue regeneration (GTR) with a bioresorbable membrane. Results were evaluated by assessing probing pocket depth, recession of the gingival margin, and clinical attachment level at baseline and at 1 and 2 years after therapy. Bone level changes were evaluated radiographically. The postoperative phase was uneventful in all cases. There was a mean probing pocket depth reduction from 8.4 to 3.6 mm, a mean increase of gingival margin recession from 1.5 to 3.0 mm, and a mean clinical attachment level change from 9.9 to 6.5 mm. Mean attachment gain was 3.4 mm. Two teeth scheduled for extraction were also treated with the same bioresorbable membrane. The histologic analysis 6 months after treatment revealed the formation of new connective tissue attachment and new alveolar bone in both cases. Based on the histologic findings it can be concluded that the clinical improvements following GTR with this type of bioresorbable membrane may represent, at least in part, true periodontal regeneration.
