Immediate placement and immediate loading of full edentulous arches in 20 periodontally compromised patients – in-line clinical case series with 3 years follow-up

Tran-Hung Lam,Dard Michel 대한치과이식임플란트학회 2021 The Korean Academy of Implant Dentistry Vol.40 No.3

Purpose: These in-line clinical case series aim to assess the cumulative implant and definitive prosthesis survival rate of full edentulous arches in periodontally compromised patients using 4 to 6 Bone Level Tapered (BLT) implants (Straumann, Basel, Switzerland) for up to 3 years of loading. Materials and Methods: Ninety-four implants were placed in 20 patients under the full controlled principle of in-line clinical case series (14 successive days of surgery). Each subject received an immediate loaded and complete-arch provisional prosthesis during 24 hours after implant surgery. The definitive prostheses were delivered within 6 to 8 weeks after implant insertion. A life table method was used to determine implant cumulative survival rate. Results: Up to 3 years of loading, our results demonstrated a cumulative implant survival rate of 98.94%. The definitive prosthesis survival rate was 100%. Conclusions: These results support the use of BLT implants according to the ProArch concept for immediate placement and immediate loading of full edentulous arches in periodontally compromised patients. These in-line case series need to be followed by long-term clinical evaluations.

Protein dynamics viewed by hydrogen exchange.

Skinner, John J,Lim, Woon K,B?dard, Sabrina,Black, Ben E,Englander, S Walter Cambridge University Press 2012 Protein science Vol.21 No.7

<P>To examine the relationship between protein structural dynamics and measurable hydrogen exchange (HX) data, the detailed exchange behavior of most of the backbone amide hydrogens of Staphylococcal nuclease was compared with that of their neighbors, with their structural environment, and with other information. Results show that H-bonded hydrogens are protected from exchange, with HX rate effectively zero, even when they are directly adjacent to solvent. The transition to exchange competence requires a dynamic structural excursion that removes H-bond protection and allows exposure to solvent HX catalyst. The detailed data often make clear the nature of the dynamic excursion required. These range from whole molecule unfolding, through smaller cooperative unfolding reactions of secondary structural elements, and down to local fluctuations that involve as little as a single peptide group or side chain or water molecule. The particular motion that dominates the exchange of any hydrogen is the one that allows the fastest HX rate. The motion and the rate it produces are determined by surrounding structure and not by nearness to solvent or the strength of the protecting H-bond itself or its acceptor type (main chain, side chain, structurally bound water). Many of these motions occur over time scales that are appropriate for biochemical function.</P>

On the Effects of Frequency Scaling Over Capacity Scaling in Underwater Networks—Part II: Dense Network Model

Shin, Won-Yong,Lucani, Daniel E.,Mé,dard, Muriel,Stojanovic, Milica,Tarokh, Vahid Springer-Verlag 2013 Wireless personal communications Vol.71 No.3

On the Effects of Frequency Scaling Over Capacity Scaling in Underwater Networks—Part I: Extended Network Model

Shin, Won-Yong,Lucani, Daniel E.,Mé,dard, Muriel,Stojanovic, Milica,Tarokh, Vahid Springer-Verlag 2013 Wireless personal communications Vol.71 No.3

Accuracy of routine digitally guided immediate full-arch rehabilitations: an observational analysis of eight patients

James Kwok Fai Chow,Adam Shui Cheong Siu,Edward Hui,Raymond Lop Keung Chow,Michel Dard 대한치과이식임플란트학회 2021 The Korean Academy of Implant Dentistry Vol.40 No.4

Purpose: Guided surgery might significantly improve the efficacy and predictability of full-arch rehabilitations. This requires highly accurate implant placement. This retrospective statistical analysis of patient records aimed at identifying the factors affecting the implant placement accuracy of guided single and bimaxillary immediate full-arch rehabilitations. Materials and Methods: Patient, anatomy, procedure, and implant-related parameters that might influence the coronal, apical and angular deviation of the implants and anchoring pins were statistically analyzed using various statistical models: Mixed regression models were used to analyze differences within groups of single parameters individually. Statistically significant associations between placement accuracy and influencing factors after eliminating covariate factors were identified using multivariable mixed regression models. Results: Patient records of 8 partially edentulous patients treated by four different surgeons and involving 11 procedures, including 61 implants, were analyzed. Average coronal, apical, and angular deviations of (1.16±0.80) mm, (1.49±0.89) mm, and (4.06±2.17)° respectively were measured. From the mixed regression analysis, gender, jaw type, implant position, bone resection, and pinhole drill guide were found to have a statistically significant association with one or more accuracy parameters. As part of the multivariable regression analysis after elimination of covariate parameters, the coronal and apical offsets appeared to be influenced by the use of pinhole drill guides (P<0.001) and angular offsets by the surgeon (P=0.063), age (P=0.027), and implant position (P=0.014). Conclusions: Digital workflows allow for the successful full-arch rehabilitation of partially and fully edentulous patients. The implant placement accuracy might be improved by considering the identified procedure, anatomic, and patient-related factors.

Quality of life, patient preferences, and implant survival and success of tapered implant-retained mandibular overdentures as a function of the attachment system

Ilze Indriksone,Pauls Vitols,Viktors Avkstols,Linards Grieznis,Kaspars Stamers,Susy Linder,Michel Dard Korean Academy of Periodontology 2022 Journal of Periodontal & Implant Science Vol.52 No.3

Purpose: A novel attachment system for implant-retained overdentures (IRODs) with novel material combinations for improved mechanical resilience and prosthodontic success (Novaloc) has been recently introduced as an alternative to an existing system (Locator). This study investigated whether differences between the Novaloc and Locator attachment systems translate into differences in implant survival, implant success, and patient-centered outcomes when applied in a real-world in-practice comparative setting in patients restored with mandibular IRODs supported by 2 interforaminal implants (2-IRODs). Methods: This prospective, intra-subject crossover comparison compared 20 patients who received 2 intra-foraminal bone level tapered implants restored with full acrylic overdentures using either the Locator or Novaloc attachment system. After 6 months of function, the attachment in the corresponding dentures was switched, and the definitive attachment system type was delivered based on the patient's preference after 12 months. For the definitive attachment system, implant survival was evaluated after 24 months. The primary outcomes of this study were oral health-related quality of life and patient preferences related to prosthetic and implant survival. Secondary outcomes included implant survival rate and success, prosthetic survival, perceived general health, and patient satisfaction. Results: Patient-centered outcomes and patient preferences between attachment systems were comparable, with relatively high overall patient satisfaction levels for both attachment systems. No difference in the prosthetic survival rate between study groups was detected. The implant survival rate over the follow-up period after 24 months in both groups was 100%. Conclusions: The results of this in-practice comparison indicate that both attachment systems represent comparable candidates for the prosthodontic retention of 2-IRODs. Both systems showed high rates of patient satisfaction and implant survival. The influence of material combinations of the retentive system on treatment outcomes between the tested systems remains inconclusive and requires further investigations.

Immediate bimaxillary full-arch reconstruction using an industrial outsourced digitally guided workflow – a feasibility demonstration

Adam S.C. Siu,James K.F. Chow,Edward Hui,Mei M. Chong,Michel Dard 대한치과이식임플란트학회 2021 The Korean Academy of Implant Dentistry Vol.40 No.4

Bimaxillary immediate full-arch restorations can be prosthodontically, surgically, and esthetically demanding. State-of-the-art computer- assisted guided surgery can significantly improve the predictability and reliability of such procedures while reducing the chair time for the patient. This case report demonstrates how such procedures can be applied using an industrially outsourced service to assist implant planning and treatment preparation. A 63-year-old partially edentulous female with a failing dentition presented at our clinic. After medical assessment and the patient s request to avoid any edentulous episodes during treatment, a digitally guided bimaxillary full-arch reconstruction with an immediate restoration was performed within one session. The surgical and restorative procedures were performed as planned, allowing an immediate provisional restoration. The comparison of the planned and actual implant positions indicated slight inaccuracies between these positions. These deviations did not affect the immediate provisionalization, functionality, or esthetics of the immediate or final prosthetic rehabilitation. Fully digitally guided workflows represent a valuable tool for the efficient and reliable immediate transition from a failing dentition to a fixed reconstruction. The application of an outsourced and assisted digital planning service allows immediate access to digitally guided surgery and can improve efficiency. Deviations between planned and actual implant positions were most likely related to the rotational degrees of freedom around the teeth used for guide retention.

Dimensional Changes Following Immediate and Delayed Implant Placement: A Histomorphometric Study in the Canine

Yi, Hee-Yong,Park, Young-Seok,Pippenger, Benjamin E.,Lee, Bongho,Miron, Richard J.,Dard, Michel QUINTESSENCE PUBLISHING CO, INC 2017 The International journal of oral & maxillofacial Vol.32 No.3

Quality of life, patient preferences, and implant survival and success of tapered implant-retained mandibular overdentures as a function of the attachment system

Ilze Indriksone,Pauls Vitols,Viktors Avkstols,Linards Grieznis,Kaspars Stamers,Susy Linder,Michel Dard 대한치주과학회 2023 Journal of Periodontal & Implant Science Vol.53 No.3

Purpose: A novel attachment system for implant-retained overdentures (IRODs) with novel material combinations for improved mechanical resilience and prosthodontic success (Novaloc) has been recently introduced as an alternative to an existing system (Locator). This study investigated whether differences between the Novaloc and Locator attachment systems translate into differences in implant survival, implant success, and patient-centered outcomes when applied in a real-world in-practice comparative setting in patients restored with mandibular IRODs supported by 2 interforaminal implants (2-IRODs). Methods: This prospective, intra-subject crossover comparison compared 20 patients who received 2 intra-foraminal bone level tapered implants restored with full acrylic overdentures using either the Locator or Novaloc attachment system. After 6 months of function, the attachment in the corresponding dentures was switched, and the definitive attachment system type was delivered based on the patient's preference after 12 months. For the definitive attachment system, implant survival was evaluated after 24 months. The primary outcomes of this study were oral health-related quality of life and patient preferences related to prosthetic and implant survival. Secondary outcomes included implant survival rate and success, prosthetic survival, perceived general health, and patient satisfaction. Results: Patient-centered outcomes and patient preferences between attachment systems were comparable, with relatively high overall patient satisfaction levels for both attachment systems. No difference in the prosthetic survival rate between study groups was detected. The implant survival rate over the follow-up period after 24 months in both groups was 100%. Conclusions: The results of this in-practice comparison indicate that both attachment systems represent comparable candidates for the prosthodontic retention of 2-IRODs. Both systems showed high rates of patient satisfaction and implant survival. The influence of material combinations of the retentive system on treatment outcomes between the tested systems remains inconclusive and requires further investigations.

Comparison of the cyclic fatigue resistance of One Curve, F6 Skytaper, Protaper Next, and Hyflex CM endodontic files

Gouédard Charlotte,Pino Laurent,Arbab-Chirani Reza,Arbab-Chirani Shabnam,Chevalier Valérie 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.2

Objectives This study compared the cyclic fatigue resistance of One Curve (C wire) and F6 Skytaper (conventional austenite nickel-titanium [NiTi]), and 2 instruments with thermo-mechanically treated NiTi: Protaper Next X2 (M wire) and Hyflex CM (CM wire). Materials and Methods Ten new instruments of each group (size: 0.25 mm, 6% taper in the 3 mm tip region) were tested using a rotary bending machine with a 60° curvature angle and a 5 mm curvature radius, at room temperature. The number of cycles until fracture was recorded. The length of the fractured instruments was measured. The fracture surface of each fragment was examined with a scanning electron microscope (SEM). The data were analyzed using one-way analysis of variance and the post hoc Tukey test. The significance level was set at 0.05. Results At 60°, One Curve, F6 Skytaper and Hyflex CM had significantly longer fatigue lives than Protaper Next X2 (p < 0.05). No statistically significant differences were found in the cyclic fatigue lives of One Curve, F6 Skytaper, and Hyflex CM (p > 0.05). SEM images of the fracture surfaces of the different instruments showed typical features of fatigue failure. Conclusions Within the conditions of this study, at 60° and with a 5 mm curvature radius, the cyclic fatigue life of One Curve was not significantly different from those of F6 Skytaper and Hyflex CM. The cyclic fatigue lives of these 3 instruments were statistically significantly longer than that of Protaper Next. Objectives This study compared the cyclic fatigue resistance of One Curve (C wire) and F6 Skytaper (conventional austenite nickel-titanium [NiTi]), and 2 instruments with thermo-mechanically treated NiTi: Protaper Next X2 (M wire) and Hyflex CM (CM wire). Materials and Methods Ten new instruments of each group (size: 0.25 mm, 6% taper in the 3 mm tip region) were tested using a rotary bending machine with a 60° curvature angle and a 5 mm curvature radius, at room temperature. The number of cycles until fracture was recorded. The length of the fractured instruments was measured. The fracture surface of each fragment was examined with a scanning electron microscope (SEM). The data were analyzed using one-way analysis of variance and the post hoc Tukey test. The significance level was set at 0.05. Results At 60°, One Curve, F6 Skytaper and Hyflex CM had significantly longer fatigue lives than Protaper Next X2 (p < 0.05). No statistically significant differences were found in the cyclic fatigue lives of One Curve, F6 Skytaper, and Hyflex CM (p > 0.05). SEM images of the fracture surfaces of the different instruments showed typical features of fatigue failure. Conclusions Within the conditions of this study, at 60° and with a 5 mm curvature radius, the cyclic fatigue life of One Curve was not significantly different from those of F6 Skytaper and Hyflex CM. The cyclic fatigue lives of these 3 instruments were statistically significantly longer than that of Protaper Next.