Purpose: To retrospectively evaluate the long-term clinical, technical, biological, and esthetic outcomes of implant supported single zirconia crowns (ISCs) intraorally cemented to Ti-base hybrid-abutments up to 16 years after placement. Materials and Methods: A total of 63 ISCs (Xive S, Camlog Screw Line, Replace Select TC NP, Branemark MK II, and 3i Osseotite) were evaluated in 36 patients at two different centers. Original Ti-bases were selected and zirconia meso structures and zirconia crowns were designed using CAD/CAM software and then milled from partially stabilized zirconia blocks. After the meso structures were cemented extraorally onto the Ti-bases, the ceramic crowns were intraorally luted to the hybrid abutments. The Ti-base ISC restorations were followed up for up to 16 years, and their clinical, biological, and esthetic outcomes were recorded at distinct time points (T1; T2) at three-year intervals. Results: 36 patients (18 men, 18 women) received 32 ISCs in the anterior region and 31 in the posterior region of the maxilla and mandible. The mean follow-up of the Ti-base ISCs was 6.93 ± 2.60 years. The mean follow-up of the implants amounted to 8.11 ± 3.26 years. No implants were lost during follow-up, resulting in a cumulative implant survival rate of 100%. Abutment screw loosening was observed in two ISCs after one year in service. The overall cumulative restorative survival rate of the Ti-base restorations reached thus 96.83%. At T2 follow-up 24% of the ISCs exhibited an increase in PD despite maintaining clinically healthy peri-implant tissue. An 11% increase in BOP and a 3.17% decrease in PI were recorded. Despite spectrophotometrically measured ΔE values indicating visible discoloration of some restorations and their peri-implant soft tissue, a low incidence of esthetic complications was observed with an average PES/WES score of ≥ 12. No correlation was found between PES (R = -0.25; p = 0.27) and WES (R = -0.18; p = 0.43) scores and digital shade determination. Conclusions: The results of the present retrospective, multicenter, cohort study indicate satisfactory clinical outcomes for intraorally cemented single zirconia crowns (ISCs) supported by Ti-base hybrid abutments. An overall esthetic superiority of Ti-base ISCs could not be confirmed. Keywords: retrospective trial, titanium base, zirconia, two-piece hybrid abutment, implant-supported single crown.

Purpose: Several procedures are performed to achieve optimal esthetic results in single-tooth implants. However, there is discordance regarding the potential benefit and risks of immediate implant loading/provisionalization. The aim of this prospective case series is to investigate the effect of immediate provisionalization of single-tooth implants at healed sites for periimplant soft-tissue conditions, focusing on papilla formation around single implants. Materials and Methods: Twelve patients received a total of 12 implants in the incisor, canine or premolar region of the upper and lower jaw at healed sites with immediate chair-side provisionalization. Four months later, the temporary crown was replaced by the permanent crown. After 40±13.1 months, clinical follow-up was conducted, assessing Probing pocket depth (PPD); Bleeding on Probing(BoP); Mucosal recession (MR) and Width of Keratinized Mucosa (KM). Papilla index (PI) was determined immediately after implant placement  (baseline), before removing the temporary crown (t1), 4 weeks after insertion of the definitive crown (t2) and at the final follow-up examination (t3) to evaluate papilla formation and its change over time. Results: None of the implants were lost. The mean PPD was 2.5±0.39 mm, BoP of 25% and 3.5 mm of KM were observed at the final follow-up. No implants showed MR. PI increased in all patients from 1.5±0.45 at baseline to 2.4±0.56 at t1, 2.6±0.47 at t2 and 3.02.6±0 at t3. The increase in PI between t0 and each individual timepoint from t1-t3 showed statistical significance. Conclusion: The present results indicate the suitability and benefit of immediate provisionalization to achieve favorable peri-implant soft-tissue conditions and papilla formation.

Die Sofortversorgung im zahnlosen Kiefer bietet dank beschleunigter Behandlung und reduzierter Behandlungstermine viele Vorteile im Vergleich zur konventionellen Versorgung. Das Ziel der in diesem Beitrag vorgestellten klinischen Studie war die Untersuchung eines neuartigen Implantatsystems mit progressivem Gewindedesign für die Sofortversorgung des zahnlosen Kiefers auf vier Implantaten. Dabei wurden die Notwendigkeit von Modifikationen des Behandlungsplans, technische Komplikationen im Rahmen der Implantation und Sofortversorgung sowie Hart- und Weichgewebeparameter nach einjähriger Belastung dokumentiert. In die Studie eingeschlossen waren insgesamt zehn Studienteilnehmer, bei denen die Insertion von 40 Implantaten und deren sofortige provisorische Versorgung erfolgten. Während der provisorischen Phase kam es in einem Fall zu einem Verlust der provisorischen Versorgung einschließlich der vier Implantate. Zudem ging ein weiteres Implantat verloren. Die Guided-Surgery-Planungen bedurften keiner Modifikationen. Im Gegensatz dazu waren bei den Implantatinsertionen und den provisorischen Versorgungen Anpassungen erforderlich. Intraoperativ waren in den meisten Fällen kleinere Variationen des Behandlungsplans nötig, bis hin zur freihändigen Insertion von zwei Implantaten. Die klinischen und radiologischen Ergebnisse der Abschlussuntersuchung nach definitiver prothetischer Versorgung und einer mittleren Belastungsdauer von 16 Monaten (10−24 Monate) sprechen für gesunde periimplantäre Verhältnisse und eine hohe Patientenakzeptanz. Keywords: Sofortversorgung, zahnloser Kiefer, Guided Surgery, Implantaterfolg

Alveolar ridge preservation procedures have been shown to significantly reduce the loss of ridge dimension of an extraction socket. As of yet, none of the alveolar ridge preservation techniques have been proven totally effective in preserving ridge morphology. The Periosteal Inhibition technique for alveolar ridge preservation involves placing a high-density polytetrafluoroethylene (d-PTFE) membrane between the periosteum and the buccal bone plate of an extraction socket. The authors hypothesize that the nonresorbable d-PTFE membrane, because of its much smaller pore diameter as compared to the size of the osteoclast precursor cells, inhibits the migration of the osteoclast precursor cells from the periosteum to the bony surface and, subsequently, their fusion to form osteoclasts. As a result, osteolytic activity on the outer surface of the socket is inhibited. The Periosteal Inhibition technique for alveolar ridge preservation is presented along with immediate implant treatment results using this treatment concept. The resulting stable ridge dimensions in these cases demonstrate a possibility that the d-PTFE membrane may effectively prevent modeling of the extraction socket by inhibiting the formation of osteoclasts on the outer bony surface.

Objectives: The present preference clinical trial compared the long-term outcome of acellular dermal matrix allograft (ADMA) versus autogenous connective tissue graft (CTG) in the treatment of gingival recessions. Method and materials: Thirty-nine consecutive patients with 233 Miller Class I and II recessions were treated by one operator (MS) with coronally advanced flaps and in addition either ADMA or CTG harvested from their palate. Clinical parameters were measured by an independent and masked assessor at baseline, 6 months, and 5 years. Results: Thirty-two patients could be recruited for long-term examination (seven dropouts). At 6 months and 5 years, all clinical parameters showed significant improvements in both groups with slightly better but statistically not significant clinical results for CTGs. At 5 years, the CTG group revealed an additional gain of keratinized mucosa width (t6m-0: CTG 1.88 mm, ADMA 1.04 mm, P = .081; and t5y-0: CTG 3.98 mm, ADMA 3.06 mm, P = .01) compared to 6 months, whereas the mean for ADMAs remained stable (intergroup comparison statistically significant, P = .010). In all other parameters in both groups, slight but not statistically significant relapses were detected. Only one minor postoperative complication at one ADMA-treated site occurred. Conclusions: Regarding the long-term results, ADMA could be an alternative treatment option to thicken soft tissue and to cover multiple gingival recessions. If the gain of keratinized mucosa width is considered as a main goal, CTG may have a slight advantage over ADMA. Keywords: acellular dermal matrix, connective tissue, gingival recession, long-term outcome, root coverage

Purpose: To investigate the optimal degree of convergence of the abutment with which the bond strength achieved by the pre-bonding method is comparable with that in direct bonding with a conventional degree of convergence. Materials and Methods: Abutments with 5.5-mm diameter, 5-mm height, 0.5-mm shoulder width, and three kinds of degrees of convergence (2, 4, and 6 degrees) were first designed by digital modeling. Their corresponding inner crowns were also modeled, and a gap of 40 μm was kept between the abutment and the inner crown. Thirty abutments and 30 inner crowns were then lathed out from a titanium plate (10 sets per degree of convergence). Six groups were defined in this study, according to the different degrees of convergence and bonding methods (direct bonding, pre-bonding) (n = 10 sets). The samples handled with direct bonding would be cleaned for reuse in tests with pre-bonding. Temporary cement was used as an adhesive, and the bond strength was tested in each set of samples. The comparison among the results was performed by the Kruskal-Wallis test. Results: The mean values of bond strength with direct bonding methods were 349.39 ± 65.75 N, 316.49 ± 54.22 N, and 277.49 ± 56.96 N, and with pre-bonding methods were 279.35 ± 48.58 N, 227.97 ± 26.72 N, and 154.6 ± 23.03 N, respectively (2, 4, and 6 degrees). No statistical difference was found among the values in direct bonding groups and, in pre-bonding groups, only the comparison between 2 and 6 degrees of convergence showed statistical significance (P = .000). Between different bonding methods, statistical differences were shown in abutments with 4 and 6 degrees of convergence (P = .006, P = .000), respectively. The bond strength with pre-bonding methods and 2 degrees of convergence showed no significant difference from that with direct bonding and 6 degrees of convergence. Conclusion: The bond strength was inversely proportional to the degree of convergence, and the bond strength of pre-bonding was lower than that of direct bonding with the same degree of convergence. When using the pre-bonding method, the bond strength between the abutment and inner crown with 2 degrees of convergence could be comparable with using the direct bonding method and abutments with conventional degrees of convergence. Keywords: bond strength, degrees of convergence, pre-bonding

Eine implantatverankerte Einzelkrone im ästhetisch sichtbaren Bereich, welche mit den benachbarten Strukturen nachhaltig perfekt harmoniert, ist bekanntlich eine große Herausforderung. Die Entscheidung für das Therapieregime einer Sofortimplantation und -versorgung bedingt daher eine sorgfältige Indikationsstellung mit entsprechender Beurteilung von Hart- und Weichgewebe des zu ersetzenden Zahnes und seiner Nachbarzähne. Indiziert das Resultat dieser Beurteilung ein Therapiekonzept zur Optimierung des ästhetischen Gesamtergebnisses, muss ein additives Gewebsmanagement erfolgen. Letzteres macht eine für den jeweiligen Patienten vorteilhafte Auswahl von chirurgischen und/oder kieferorthopädischen Maßnahmen sowie ggf. die Anwendung einer Zahnreplantation notwendig. Zusätzlich ist das Zeitregime der genannten adjuvanten Eingriffe in Relation zur Sofortimplantation und -versorgung zu definieren. Die daraus resultierende Komplexität soll mit Hilfe von in dem Beitrag vorgestellten Entscheidungsbäumen leichter handhabbar und so die Erstellung von fallspezifischen Therapieregimen erleichtert werden. Keywords: Sofortimplantation, Sofortversorgung, Frontzahntrauma, Frontzahnverlust, Zahnreplantation, kieferorthopädische Extrusion, Weichgewebsmanagement, Knochenaugmentation, Therapie-regime, Frontzahnästhetik, entzündliche Extraktionsalveole, Weichgewebsrezession

Aim: The purpose of this literature review is to systematically evaluate the impact of immediate implant placement and restoration (IIPR) on hard and soft tissues and to identify clinical parameters which influence the outcome. Materials and methods: An electronic search of the PubMed database was performed from January 2000 to September 2015. A further hand search was conducted in selected journals and only abstracts published in English were considered for review. Human clinical trials with at least 10 participants and which reported hard and soft tissue outcomes were assessed. Randomised controlled trials (RCT), prospective, prospective comparative and retrospective studies were considered. The effects of the following clinical parameters on hard and soft tissue outcomes were analysed: type of implant, primary stability, gingival biotype, flapless surgery, tooth extraction, spatial arrangement of the implant, socket grafting, the gap between implant surface and alveolar wall and the loading protocol. Results: 17 studies (four RCT, six prospective, two comparative prospective, three controlled cohort and two retrospective studies) were included with 626 censored IIPR in 609 patients. A total of 411(65.56 %) implants were placed flapless vs 215 implants after raising a mucoperiosteal flap. Five studies defined raising a mucoperiostal flap as a mandatory part of the surgical protocol. The mean of the remaining gap in between the implant surface and the alveolar wall, the so-called "jump space", was reported for 170 implants ranging from 1.38 mm to 2.25 mm. Two hundred and one implant sites were not grafted, 405 were grafted, mostly with bone substitutes; for 20 no information was available. For 419 implants, a minimum insertion torque of ≥ 32 Ncm or an ISQ value of ≥ 60 was reached; for 53 implants an insertion torque of 25 Ncm was accepted. The implants were mostly placed palatinally of the jaw bone. The vertical position of the platform was reported either to be 0.5 to 1.0 mm below the vestibular bone crest or 3 to 4 mm apical to the adjacent cementoenamel junction of the neighbouring tooth. Post-insertion healing with a non-functional occlusion occurred for 97.8% of the implants. The final single crowns were inserted 3 to 6 months after implant placement. The IIPR resulted in a high success (97.96 %) and survival rate (98.25%) after a mean followup period of 31.2 months. The soft-tissue biotype was evaluated in 379 (60.5%) sites as thick. The mean crestal bone and the mean interproximal mucosa level changes were less than 1 mm compared to the baseline. The midfacial periimplant mucosal level change was less than 0.95 mm. This level was reached for both thin and thick soft-tissue biotypes, without a significant difference. Only in one study did the thin biotypes show a significantly higher recession. Conclusion: The systematic review revealed promising results for immediately placed and immediately restored implants (IIPR) in the anterior maxilla. The possible options of flapless surgery and absence of grafting of the socket allows a minimal surgical intervention. However, a strict patient selection seemed mandatory for all included clinical trials. Keywords: immediate implant placement, immediate implant restoration, peri-implant tissue remodelling, single-tooth replacement

This report describes the use of laboratory-fabricated crown intaglio replicas for extraorally prepared cementation of fixed restorations to implants. This technique minimizes excess cement and may therefore reduce the risk of cement-related marginal peri-implant bone loss. It is unclear whether the remaining thin layer of luting agent provides sufficient retention if low-adhesive zinc oxide (ZnO) cement is used. In 85 consecutive patients, 113 single crowns were cemented to implants using extraoral cementation technique (ECT) and ZnO cement. All patients were followed for 6 months and investigated for decementation. Seven events of decementation (incidence: 6.19%) were found in 7 patients (8.24%). ECT may represent a viable cementation technique for implant-supported single crowns, even using low-adhesion cements.

Purpose: The purpose of this study was to evaluate the efficacy of the ridge-splitting technique in the anterior maxilla, using piezoelectric surgery for immediate implant placement. Study outcomes were compared with those of implant placement in the same patients using the conventional drilling technique. Materials and Methods: Ten patients received a total of 22 implants in the anterior maxilla, 11 of which were placed using a ridge-splitting procedure (test group) and the other 11 using the conventional drilling procedure (control group). Ridge width (RW), crestal bone level (BL), and implant stability quotient (ISQ) were measured at different points in time. Data were analyzed and compared between the groups using analysis of variance (ANOVA) and paired-sample t tests at a significance level of 5%. Results: For the test group, the gain in RW was not stable in time because at 6 months postoperatively, the RW lost some of the initial gain; however, the net gain was still significant. At 6 months postoperatively, BL was similar for both groups. The net bone loss on the mesial aspect and the average of the mesial and the distal measures did not differ significantly between both groups. ISQ values sharply increased at 3 months postoperatively in the test group. All implants met the modified Albrektsson criteria (1989) for success. Conclusion: The results from this study support the efficacy and safety of ridge expansion using piezoelectric surgery for implant insertion in the anterior maxilla. The modest net gain in bone width suggests that additional hard and soft tissue augmentation may be necessary, especially in the esthetic zone. ISQ values suggest a minimum healing time of 3 months before loading the implants that have been inserted using this ridge-splitting protocol. Keywords: bone expansion, dental implant, piezoelectric surgery, ridge splitting