International Journal of Esthetic Dentistry (EN), 1/2022
PubMed ID (PMID): 35175007Pages 42-56, Language: English
The esthetic success of a case requiring implant therapy mainly depends on both the correct planning and the surgical-prosthetic execution. However, planning and surgical implementation according to prosthetically guided criteria are not always possible due to contingent anatomical limitations. When this is further complicated by the presence of mucogingival deficiencies in a highly visible esthetic area, the management of the case can become very complex. The present case report describes the presurgical and surgical management of a case of maxillary lateral incisor agenesis in the absence of sufficient vertical space. Through orthodontic therapy, the opening of the deep overbite and the alignment of the maxillary and mandibular arches were obtained, allowing for an implant positioning without compromises dictated by anatomical limitations. Finally, through mucogingival surgery and careful management of the provisional prosthetic phase, an optimal esthetic profile was achieved.
International Journal of Esthetic Dentistry, 1/2022
Pages 40-53, Language: German
Wenn Patienten eine Implantattherapie benötigen, hängt der ästhetische Erfolg der Behandlung genauso von einer korrekten Planung ab wie von der chirurgischen und prothetischen Ausführung. Allerdings ist aufgrund individueller anatomischer Hindernisse eine Planung und chirurgische Umsetzung nach prothetischen Kriterien nicht immer möglich. Wird die Situation durch Weichgewebedefekte an gut sichtbaren, ästhetisch relevanten Stellen zusätzlich verkompliziert, kann die Behandlung sehr anspruchsvoll werden. Im vorliegenden Fallbericht wird die prächirurgische und chirurgische Behandlung in einem Fall beschrieben, in dem die oberen lateralen Schneidezähne nicht angelegt waren und ein unzureichendes vertikales Platzangebot bestand. Auf kieferorthopädischem Weg wurden zunächst der ausgeprägte Tiefbiss korrigiert und der obere und untere Zahnbogen reguliert, um eine Implantatsetzung ohne Einschränkungen durch die anatomische Situation zu ermöglichen. Mithilfe parodontalchirurgischer Maßnahmen und der sorgfältigen Ausführung der provisorischen und definitiven prothetischen Versorgung konnte ein ideales ästhetisches Profil hergestellt werden.
International Journal of Periodontics & Restorative Dentistry, 2/2020
DOI: 10.11607/prd.3597, PubMed ID (PMID): 32032402Pages 193-201, Language: English
This retrospective study evaluated hard and soft tissue response and reported mechanical and technical complications around computer-aided design/ computer-assisted manufactured (CAD/CAM) abutments. A total of 123 patients restored with titanium, gold-hue titanium, and zirconia CAD/CAM abutments were included (N = 291). Each patient was followed up for at least 2 years. Clinical and radiographic parameters were assessed annually and complications were recorded. No implant or reconstruction failures were reported. One fracture of a zirconia abutment occurred. The prosthetic survival rate after 4 years of function for restorations and abutments was 100% and 99.66%, respectively. No significant differences in biologic and radiographic indices were found. The bleeding on probing index was positive at 42% of implant sites, and it had no significant correlation with the overall change in marginal bone level (0.02 mm) of bone gain. The short-term survival of CAD/ CAM abutments was reliable, no matter of the material used for manufacturing.
International Journal of Oral Implantology, 1/2019
PubMed ID (PMID): 31116191Pages 105-113, Language: English
Purpose: To evaluate the reliability of a conometric system for fixed retention of complete prostheses (CPs) on four implants after 5 years of function.
Materials and methods: Twenty-five patients with a completely edentulous mandible received four implants supporting a CP. A total of 100 implants were immediately loaded with CPs on conometric abutments. A follow-up of 5 years was observed for each patient. Outcome measures were prosthesis and implant success, complications, probing pocket depth changes, marginal bleeding and plaque changes, and patient satisfaction.
Results: One patient dropped-out. In total, 96 implants supporting the 24 CPs completed the follow-up examination at 5 years. No implant failed. Two framework fractures occurred after 4 and 5 years of function. No loss of retention was recorded for the CPs. Mucositis was recorded for two implants after 1 year of prostheses function for two patients, for one implant after 3 years and for two implants after 4 years in different patients and successfully treated with interceptive supportive therapy. No significant differences were found between Plaque Index (PI) at baseline and after 2 years (P = 1.0); similar findings were calculated between PI at baseline and after 5 years (P = 0.6) of function. At baseline, after 2 and after 5 years, respectively, 69%, 64% and 56% of implants showed a PI of 0; 31%, 36% and 44% of implants showed a PI between 1 and 3. Modify Bleeding Index (MBI) was not significantly different both between baseline and after 2 years of function (P = 1.0) and between baseline and 5 years of function (P = 0.5). At baseline, after 2 and after 5 years, respectively, 69%, 65% and 61% of implants showed a MBI of 0; 27%, 28% and 29% of implants showed a MBI of 1; and 4%, 7% and 10% of implants showed a MBI of 2. The mean probing pocket depth was 1.2 ± 0.4 mm at baseline, 1.2 ± 0.4 mm after 2 years and 1.4 ± 0.5 mm after 5 years of function. The differences were not statistically significant between baseline and 2 years (P = 1.0) and between baseline and 5 years (P = 0.1). From the patient satisfaction questionnaire, 85% percent of patients were satisfied from both aesthetic and functional points of view after 5 years of conometric prostheses function.
Conclusions: The present implant-supported conometric retention system can be used to give fixed retention to a CP supported by four implants. An adequate metal framework should be provided to the definitive restoration in order to avoid fractures in the long term.
Keywords: conometric retention, dental implants, edentulous mandible, fixed prosthesis
Conflict of interest statement: No conflict of interest was declared by authors in the present study design and clinical application. No donation of free materials, prostheses or any other s
International Journal of Periodontics & Restorative Dentistry, 2/2018
DOI: 10.11607/prd.3161, PubMed ID (PMID): 29447322Pages 277-280, Language: English
The conometric retention system was proposed and described as a predictable alternative to retain fixed implant-supported complete dentures and, more recently, to retain fixed partial restorations. Currently available studies describe a technique based on the Ankylos (Dentsply) implant system and stock conic coupling abutments. The purpose of this case series study is therefore to demonstrate the possibility of using Atlantis computer-aided design/ computer-assisted manufacture technology to produce Conus abutments (Dentsply) and using the fixed conometric retention with other implant brands for which appropriate stock conic coupling abutments are not available.
The International Journal of Oral & Maxillofacial Implants, 1/2018
DOI: 10.11607/jomi.5411, PubMed ID (PMID): 29340342Pages 23-30, Language: English
Purpose: The aim of this in vitro study was to verify whether or not stock and computer-aided design/ computer-aided manufacturing (CAD/CAM) abutments show similar precision in the connection with the respective implants.
Materials and Methods: Ten CAD/CAM titanium abutments were compared with 10 stock titanium abutments. Each abutment fit a regular-platform implant (Institute Straumann). Implants and abutments were measured independently and then connected. During the connection procedure, the torque was measured using a six-axes load cell. Then, outer geometric features of the implant-abutment connection were measured again. Finally, the assembly was sectioned to provide the analysis of inner surfaces in contact. The geometric measurements were performed using a multisensored opto-mechanical coordinate measuring machine. The following parameters were measured and compared for the CAD/CAM and stock titanium abutment groups, respectively: width of interference and interference length between the conical surfaces of the implant and abutment; and volume of material involved in the implant-abutment connection.
Results: Interference width mean ± SD values of 18 ± 0.5 and 14 ± 0.5 μm were calculated for the stock and CAD/CAM titanium abutment groups, respectively. The difference was statistically significant (P = .02). Furthermore, the interference length mean ± SD values of 763 ± 10 and 816 ± 43 μm were calculated for stock and CAD/CAM titanium abutment groups, respectively. The difference was also statistically significant (P = .04). Finally, the volume of material involved in the implant-abutment connection was compared between stock and CAD/CAM titanium abutment groups; the mean ± SD values of 0.134 ± 0.014 and 0.108 ± 0.023 mm3 were significantly different (P = .009).
Conclusion: Both standard and CAD/CAM abutment groups showed a three-dimensional (3D) seal activation after the screw tightening. Nevertheless, stock titanium abutments showed a significantly higher volume of material involved in the implant-abutment connection compared with that of CAD/CAM titanium abutments.
Keywords: CAD/CAM abutments, implant-abutment connection, stock titanium abutments
International Journal of Periodontics & Restorative Dentistry, 5/2017
DOI: 10.11607/prd.3184, PubMed ID (PMID): 28817129Pages 656-665, Language: English
The aim of this study was to compare the interproximal papilla stability of restorations supported by computer-aided design/computer-assisted manufacture (CAD/CAM) abutments to those supported by prefabricated stock abutments in anterior areas over a 2-year follow-up. Abutments were selected depending on implant inclination and thickness of buccal peri-implant soft tissues from the following: zirconia stock, titanium stock, zirconia CAD/CAM and titanium CAD/ CAM. Differences between the height of the papilla tip were measured (REC). Results: REC values of titanium and zirconia CAD/CAM abutments were significantly lower than those of titanium and zirconia stock. The use of titanium and zirconia CAD/CAM abutments is related to better interproximal papillae stability.
International Journal of Periodontics & Restorative Dentistry, 2/2015
DOI: 10.11607/prd.2241, PubMed ID (PMID): 25738345Pages 246-254, Language: English
The aim of this prospective randomized clinical study was to evaluate, by means of an image analysis system, the efficacy of two different surgical procedures for the treatment of Miller Class I and II maxillary gingival recession. Patients treated for maxillary gingival recession were recruited and randomly divided into two groups: patients who received a coronally advanced flap with connective tissue graft (CAF + CTG) or CAF alone. Outcome parameters included complete root coverage, recession reduction, and keratinized tissue amount. Twenty-five patients completed the 12-month follow-up period. Patients in the CAF + CTG group showed a better primary outcome- gingival recession at 12 months-than CAF patients (P = .0001). Gingival recession at 12 months had a median of 0.5 (interquartile range [IQR] 0.5 to 0.6) in the CAF + CTG group and a median of 1.0 (IQR 0.9 to 1.1) in the CAF group. CAF + CTG and CAF groups had similar complete root coverage at 6 and 12 months. Recession and keratinized tissue width significantly decreased over time (P < .0001), with no effect of treatment or of treatment over time. Buccal probing depth had similar values over time (P = .28) and in the two groups (P = .52). Buccal clinical attachment level had similar values in the two groups (P = .87); moreover, mesial and distal clinical attachment levels did not show any variation over time (P = .88 and P = .68, respectively). By means of a computerized image analysis system better outcomes in terms of recession reduction after 12 months of follow-up were measured for maxillary gingival recessions treated with CAF and CTG. Adjunctive application of a CTG under a CAF increased the probability of achieving complete root coverage in maxillary Miller Class I and II defects (61.5% versus 83.3%; P = .38). Both treatments were equally effective in providing a consistent reduction of the baseline recession.
Pages 401-409, Language: German
Der Einzelzahnersatz mit dentalen Implantaten im ästhetischen Bereich der Maxilla kann aufgrund von Schwierigkeiten mit dem Management des periimplantären Weichgewebes oft Probleme bereiten, da dieses dem Weichgewebe der angrenzenden natürlichen Zähne gleichen sollte. In den letzten Jahren wurde eine Vielzahl an mukogingivalen Techniken vorgestellt. Die besten Ergebnisse lassen sich jedoch mit subepithelialen Bindegewebetransplantaten erzielen. Allerdings erhöht die Bindegewebeentnahme auch die Morbidität und der chirurgische Eingriff dauert länger. Daher wurden viele Bemühungen in die Entwicklung xenogener Weichgewebeersatzmaterialien investiert. In diesem klinischen Fallbeispiel berichten wir von der Extraktion eines frakturierten maxillären lateralen Schneidezahns und der Sofortimplantation in die frische Extraktionsalveole in Kombination mit einer gerichteten Knochenregeneration (GBR). Anschließend wurde aufgrund eines persistierenden horizontalen periimplantären Weichgewebedefekts eine neue xenogene Kollagenmatrix unter einem Vollschichtlappen inseriert. Das Implantat wurde mit einer temporären Kunststoffkrone belastet, die später durch eine Keramikverblendkrone ersetzt wurde. Die Heilung wurde über einen Zeitraum von 12 Monaten beobachtet.
Keywords: Periimplantäres Weichgewebe, Weichgewebetransplantat, Guided-Bone-Regeneration, ästhetische Maxilla, Sofortimplantation
The International Journal of Oral & Maxillofacial Implants, 1/2014
DOI: 10.11607/jomi.3236, PubMed ID (PMID): 24451869Pages 178-184, Language: English
Purpose: The purpose of this study was to evaluate the three-dimensional radiographic changes of 100% anorganic bovine bone xenograft volume in a grafted maxillary sinus, based on a computerized analysis of cone-beam computed tomography (CBCT) scan.
Materials and Methods: A maxillary sinus augmentation procedure done with a lateral approach using 100% anorganic bovine bone was performed in 20 patients. A CBCT scan of the grafted area was taken immediately after the procedure (T1) and 8 to 9 months later (T2). CBCT scan data were analyzed with image processing software to evaluate differences in the volume of grafted material between T1 and T2. Residual ridge height and width were also measured at T1.
Results: The mean residual bone height and width at the implant sites was 4.40 ± 0.87 mm and 7.9 ± 2.22 mm, respectively. The mean graft volume was 1,432 ± 539 mm3 and 1,287 ± 498 mm3 at T1 and T2, respectively. A significant difference in graft volume was found between T1 and T2 data by paired t test (P = .01). The mean ratio between the volume at T2 and the volume at T1 was 0.90 ± 0.12, meaning a graft volume contraction of 10%.
Conclusion: Within the limits of the present investigation, good stability of anorganic bovine bone graft volume up to 8 months after the grafting procedure was demonstrated. Three-dimensional computed tomographic volumetric assessment seems to be a promising approach to quantify long-term changes in the regenerated area.
Keywords: bone graft, maxillary sinus, three-dimensional radiographic changes