Publications by authors named "Martin Schimmel"

Article Synopsis
  • The study aimed to compare the accuracy of new wireless intraoral scanners (IOSs) with traditional wired IOSs in different scenarios related to fixed partial dentures (FPDs).
  • Models of partially edentulous maxillae were scanned using both types of scanners and results were analyzed against reference scans to measure trueness and precision.
  • Findings revealed that while the wireless IOSs showed good accuracy, wired IOSs outperformed in certain metrics, particularly in angular and interimplant distance measurements, with higher inaccuracies noted in posterior FPDs.
View Article and Find Full Text PDF

Purpose: The COVID-19 pandemic raised the question about the extent of microbial exposure encountered by dentists during dental therapy. The purpose of this study was to quantify microbial counts on surgical masks related to duration and type of dental therapy, as well as patient oral health variables.

Materials And Methods: Sterile filter papers were fixed on surgical masks used during routine daily dental therapy.

View Article and Find Full Text PDF

Objective: To evaluate the effect of build orientation on the fabrication trueness and fit of additively manufactured 2-piece zirconia abutments when compared with those manufactured subtractively in 3 mol% and 4 mol% yttria-stabilized zirconia (3Y-TZP and 4Y-TZP).

Methods: A titanium-base (Ti-base) abutment was digitized with a scan body and an industrial scanner to design a 2-piece zirconia abutment with a 50 µm cement gap. This design was used to manufacture zirconia abutments additively in different orientations (0-degree, AM-0; 15-degree, AM-15; 30-degree, AM-30; 45-degree, AM-45; 180-degree, AM-180) and subtractively from 3Y-TZP and 4Y-TZP (SM-3 and SM-4) (n=5).

View Article and Find Full Text PDF

Objective: This case report illustrates a clinical scenario of a patient with insufficient crowns, gold onlays and localized tooth pain in the posterior teeth, treated with partial and full coverage lithium disilicate restorations.

Clinical Considerations: A female patient presented in the clinics, complaining about tooth pain and unesthetic metal restorations. After a thorough examination, diagnosis and treatment plan, the existing restorations were removed, and a defect-oriented preparation was done to preserve as much as possible of the remaining tooth structure.

View Article and Find Full Text PDF

Statement Of Problem: Currently available 3-dimensional (3D) additively manufactured (AM) resins used for definitive restorations have different chemical compositions and viscosities. The fabrication trueness and margin quality of laminate veneers additively manufactured with different resins have not been extensively studied.

Purpose: The purpose of this in vitro study was to evaluate the fabrication trueness and margin quality of AM and subtractively manufactured (SM) definitive resin-based laminate veneers.

View Article and Find Full Text PDF
Article Synopsis
  • The study examined how the design of implant analogs and the thickness of printing layers influence the accuracy of digitally made casts compared to traditional stone casts.
  • Results indicated that the type of analog used and the layer thickness significantly affected both linear and angular deviations, with S analogs generally demonstrating better accuracy than N analogs.
  • The findings suggest that using S-50 analogs might provide greater positional accuracy than other groups, emphasizing the importance of design and manufacturing methods in dental applications.
View Article and Find Full Text PDF

Background: Within the fields of medicine and music, increasing attention is given to evidence indicating music performance being an occupational risk factor for temporo-mandibular disorders (TMD).

Objectives: Assessment of self-reported painful TMD symptoms among student and professional musicians.

Methods: Using Survey Monkey software, the German version of the 'TMD-Pain-Screener' was distributed electronically to professional and student musicians in Europe.

View Article and Find Full Text PDF

Purpose: To evaluate the distortion probability in impressions of completely dentate arches when different impression materials are used in relation to operator experience.

Materials And Methods: A total of 28 students (Group A) and 7 dentists (Group B) performed three maxillary impressions on 28 participants, each using vinyl siloxane ether (VSE), polyether (PE), and irreversible hydrocolloid (IHC). Gypsum master casts were fabricated and subsequently digitized.

View Article and Find Full Text PDF

Objectives: This study aimed to compare the design outcomes of anterior crowns generated using deep learning (DL)-based software with those fabricated by a technician using conventional dental computer-assisted design (CAD) software without DL support, with a focus on the evaluation of crown morphology, function, and aesthetics.

Methods: Twenty-five in vivo datasets comprising maxillary and mandibular arch scans of prepared maxillary central incisors were utilized to design anterior crowns by using three methods: 1) a DL-based method resulting in as-generated outcome (DB), 2) a DL-based method further optimized by a technician (DM), and 3) a conventional CAD-based method (NC, control). Evaluations were conducted for crown morphology (total discrepancy volume (TDV), root mean square (RMS), positive average (PA) and negative average (NA) deviations), functional aspects (incisal path: deviations, length, and mean inclination), and aesthetics (crown width, height, width-to-height ratio, angular radius of mesioincisal line angle, proximal contact length, and tooth axis angle).

View Article and Find Full Text PDF

Aim: This is a report of the 5-year results of a two-group parallel randomized clinical trial comparing longitudinal implant stability, and clinical and radiographic peri-implant outcomes of mandibular overdentures retained by one (1-IOD group) or two (2-IOD group) implants.

Methods: All participants received 4.1 mm diameter tissue-level implants (Straumann Standard Plus - SLActive, Institut Straumann AG), installed in the mandible midline (1-IOD; n = 23) or the lateral incisor-canine area bilaterally (2-IOD; n = 24), and loaded after 3 weeks.

View Article and Find Full Text PDF

Objectives: To digitally evaluate the trueness and fit of additively and subtractively manufactured fixed complete dentures in materials intended for definitive use.

Methods: An edentulous maxillary model with implants at the left first molar, left canine, right canine, and right first molar site was digitized and a fixed complete denture was designed. This design was used to fabricate fixed dentures in an additively manufactured resin for definitive use (AM), a high-impact polymer composite (SM-CR), and a strength gradient zirconia (SM-ZR) (n = 10).

View Article and Find Full Text PDF

(1) Background: Insufficient data exist regarding oral function among older adults in Europe. Therefore, we aimed to assess and compare oral function between older in- and outpatients and identify predictors of low masticatory performance. (2) Methods: Patients were consecutively recruited from the outpatient center ( = 31) and the inpatient geriatric department ( = 31) at a tertiary University Hospital in Switzerland in 2023.

View Article and Find Full Text PDF

Objective: This 2-year prospective study reports the incidence of prosthetic complications and maintenance events after treatment with mandibular overdenture retained by four mini implants opposed to a maxillary denture.

Methods: Implant intervention included flapless or flapped surgery combined with immediate or delayed loading, as part of a randomized clinical trial. Four one-piece titanium-zirconium mini-implants (Straumann Mini Implant System) were inserted, and the retentive PEEK elements (Optiloc) were incorporated into the overdenture using chairside procedures.

View Article and Find Full Text PDF

The positive impact of implant interventions on dental patient-reported outcomes is an essential parameter of treatment effectiveness. This study assessed the 2-year changes in patient satisfaction and oral health-related quality of life (OHRQoL) of edentulous patients treated with a four mini implant mandibular overdenture (IOD) METHODS: The study was planned as a 2 × 2 factorial randomized clinical trial that tested two surgical approaches (flapped or flapless) and two loading protocols (immediate and delayed) using a titanium-zirconium mini implant (Straumann Mini Implant System®) and a PEEK retentive system (Straumann® Optiloc® Retentive System). Outcome measures (OHIP-Edent scores and the McGill Denture Satisfaction questionnaire) were assessed before treatment and at the 3-, 6-, 12-, and 24-month follow-ups.

View Article and Find Full Text PDF

Objective: To assess the relative position of mini-implants to retain a mandibular overdenture, according to the surgical protocol, technical and anatomical factors.

Methods: Mandibular cone-beam computed tomography (CBCT) scans were analyzed for 73 patients who received four one-piece titanium-zirconium mini-implants. Drilling was performed using a 1.

View Article and Find Full Text PDF

Background: There is limited knowledge on the fabrication trueness and fit of additively or subtractively manufactured complete-arch implant-supported frameworks in recently introduced polymers.

Purpose: To evaluate the trueness and marginal fit of additively or subtractively manufactured polymer-based complete-arch implant-supported frameworks, comparing with those of strength gradient zirconia frameworks.

Materials And Methods: A typodont model with 4 implants (left first molar (abutment 1), left canine (abutment 2), right canine (abutment 3), and right first molar (abutment 4)) was digitized (ATOS Core 80 5MP) and an implant-supported complete-arch framework was designed.

View Article and Find Full Text PDF

Purpose: To analyse the association of masticatory performance and oral health-related quality of life in a representative population of individuals residing in communities in Switzerland aged ≥ 45 years.

Materials And Methods: In total, 100 subjects completed two dedicated and validated questionnaires on their demographic data and the Geriatric Oral Health Assessment Index. A mixing ability test was performed for assessing masticatory performance.

View Article and Find Full Text PDF

Objectives: To compare implant supported crowns (ISCs) designed using deep learning (DL) software with those designed by a technician using conventional computer-aided design software.

Methods: Twenty resin-based partially edentulous casts (maxillary and mandibular) used for fabricating ISCs were evaluated retrospectively. ISCs were designed using a DL-based method with no modification of the as-generated outcome (DB), a DL-based method with further optimization by a dental technician (DM), and a conventional computer-aided design method by a technician (NC).

View Article and Find Full Text PDF

Objectives: To compare the positional trueness of implant-crown bonding to titanium bases (Ti-bases) using different bonding protocols.

Materials And Methods: A nonprecious alloy model with a single implant at the mandibular right first molar site was digitized, then a single implant crown was designed. The crown was milled, adhesively cemented on a Ti-base, and screw-retained on the implant in the master model to obtain a reference scan.

View Article and Find Full Text PDF

Unlabelled: Effect of model resin and shaft taper angle on the trueness and fit of additively manufactured removable dies in narrow ridge casts Purpose. To evaluate how model resin and shaft taper affect the trueness and fit of additively manufactured removable dies in narrow ridge casts.

Material And Methods: A typodont model with a prepared mandibular molar was scanned to design virtual dies with different shaft tapers (0-degree (straight), 5-degree, and 10-degree tapered).

View Article and Find Full Text PDF

Objective: To assess the clinical outcomes by means of implant and prosthetic survival of late placed and early loaded implants with a hydrophilic, moderately rough surface for partially edentulous patients after a follow-up of 8.5 to 9.5 years.

View Article and Find Full Text PDF

Objective: This prospective study is part of a randomised clinical trial and reports the changes in masticatory performance (MP) and bite force, and explores their influential factors, 1 year after the provision of mandibular overdentures retained by four titanium-zirconium mini implants.

Methods: Edentulous patients received conventional complete dentures, followed by placement of four mini implants (Straumann® Mini Implant System) in the anterior mandible and converting the conventional prosthesis into a mandibular overdenture. Treatment protocols were randomised using a 2×2 factorial design combining different surgical (flapped vs.

View Article and Find Full Text PDF

This study presents the first 10-year follow-up investigation of the implant survival and peri-implant outcomes of one-piece mini dental implants (MDIs) retaining mandibular implant overdentures (IODs), including marginal bone level alterations (ΔMBLs), clinical peri-implant parameters, and complications. Twenty participants with horizontally atrophied mandibles received complete dentures and four MDIs (diameter 1.8 mm) at baseline.

View Article and Find Full Text PDF

Purpose: To evaluate the effect of model resin type and time interval on the dimensional stability of additively manufactured diagnostic casts.

Materials And Methods: Ten irreversible hydrocolloid impressions and 10 impressions from an intraoral scanner were made from a reference maxillary stone cast, which was also digitized with a laboratory scanner. Conventional impressions were poured in type III stone (SC), while digital impressions were used to additively manufacture casts with a nanographene-reinforced model resin (GP) or a model resin (DM).

View Article and Find Full Text PDF

Objective: This study aimed to evaluate the reliability of two methods used to assess masticatory performance and attempt to correlate them to achieve interchangeability between the methods.

Methods: Twelve healthy dentate volunteers (men = 6, women = 6; mean age = 28.3 ± 4.

View Article and Find Full Text PDF