[ZApprO versus ZÄPrO: results of a first comparative study]. / ZApprO versus ZÄPrO: Ergebnisse einer ersten Vergleichsstudie.

BACKGROUND: More than 60 years after the enactment of the first Licensing Regulations for Dentists (ZÄPrO), a new Licensing Regulations for Dentists, the ZApprO, was implemented in 2020. The aims of this study were to evaluate and compare the "Course in Technical Propaedeutics" (TPK) with the course "Dental Propaedeutics with a Focus on Dental Technology" (ZPDT), which are based on different legal foundations. METHODS: The following parameters were compared after completion of the courses: (1) theoretical and practical knowledge, (2) regular department-internal learner evaluation, and (3) special evaluation of learning conditions by the learners and (4) by the instructors. The theoretical and practical exams and the questionnaires were analyzed in terms of their test-statistical characteristics (difficulty, discrimination index, internal consistency). Group comparisons between TPK and ZPDT were conducted using t­tests for independent groups. RESULTS: Significant differences were only detected in the students' evaluation of their learning conditions, with theoretical and practical knowledge transfer being rated lower in the TPK than in the ZPDT. DISCUSSION: The comparable results of the knowledge assessments and the regular learner evaluation, triangulated with the comprehensive learner and instructor evaluation, allowed a broad assessment of both courses. The significant differences identified provide opportunities for optimization of the newly implemented ZPDT course.

Three-dimensional changes of a porcine collagen matrix and free gingival grafts for soft tissue augmentation to increase the width of keratinized tissue around dental implants: a randomized controlled clinical study.

BACKGROUND: Emerging clinical data points to the relevance of the presence of keratinized tissue (KT). Although apically positioned flap/vestibuloplasty along with free gingival graft (FGG) is considered as a standard intervention for augmenting KT, substitute materials appear to be a viable treatment alternative. So far, there is a lack of data investigating the dimensional changes at implant sites treated with soft-tissue substitutes or FGG. AIM: The present study aimed at comparing three-dimensional changes of a porcine derived collagen matrix (CM) and FGG for increasing KT at dental implants over a 6-month follow-up period. MATERIALS AND METHODS: The study enrolled 32 patients exhibiting deficient KT width (i.e., < 2 mm) at the vestibular aspect who underwent soft tissue augmentation using either CM (15 patients/23 implants) or FGG (17 patients/31 implants). The primary outcome was defined as tissue thickness change (mm) at treated implant sites between 1- (S0), 3- (S1), and 6-months (S2). Secondary outcomes considered changes of KT width over a 6-month follow-up period, surgical treatment time, and patient-reported outcomes. RESULTS: Dimensional analyses from S0 to S1 and from S0 to S2 revealed a mean decrease in tissue thickness of - 0.14 ± 0.27 mm and - 0.04 ± 0.40 mm in the CM group, and - 0.08 ± 0.29 mm and - 0.13 ± 0.23 mm in the FGG group, with no significant differences noted between the groups (3 months: p = 0.542, 6 months: p = 0.659). Likewise, a comparable tissue thickness decrease was observed from S1 to S2 in both groups (CM: - 0.03 ± 0.22 mm, FGG: - 0.06 ± 0.14 mm; p = 0.467). The FGG group exhibited a significantly greater KT gain after 1, 3 and 6 months compared to the CM group (1 month: CM: 3.66 ± 1.67 mm, FGG: 5.90 ± 1.58 mm; p = 0.002; 3 months: CM: 2.22 ± 1.44; FGG: 4.91 ± 1.55; p = 0.0457; 6 months: CM: 1.45 ± 1.13 mm, FGG: 4.52 ± 1.40 mm; p < 0.1). Surgery time (CM: 23.33 ± 7.04 min.; FGG: 39.25 ± 10.64 min.; p = 0.001) and postoperative intake of analgesics were significantly lower in the CM group (CM: 1.2 ± 1.08 tablets; FGG: 5.64 ± 6.39 tablets; p = 0.001). CONCLUSIONS: CM and FGG were associated with comparable three-dimensional thickness changes between 1 and 6 months. While a wider KT band could be established with FGG, the use of CM significantly reduced surgical time and patients´ intake of analgesics.

Effectiveness of modified and control protocols for the surgical therapy of combined peri-implantitis-related defects. A retrospective analysis.

OBJECTIVES: To compare the clinical effectiveness of control and two modified protocols for surgical therapy of combined peri-implantitis-related defects. MATERIALS AND METHODS: A total of n = 36 patients (n = 40 implants) diagnosed with combined supra- and intrabony defects were identified for this retrospective analysis. All protocols considered access flap surgery, granulation tissue removal and implant surface decontamination using a titanium brush. The control combined protocol included implantoplasty at supracrestal/ buccal- and reconstructive therapy at intrabony components using a particulate natural bone mineral + a native collagen membrane (CM) (n = 11 patients, n = 11 implants, CP). The modified protocols included the augmentation at both supra- and intrabony defect components using either a collagen-stabilized natural bone mineral (BOC) (n = 15 patients, n = 15 implants, MP1), or BOC mixed with autogenous bone chips + CM (n = 10 patients, n = 14 implants, MP2). Linear mixed effects analyses were used to assess the changes in clinical parameters (i.e., bleeding on probing - BOP, probing pocket depth - PD, and mucosal recession - MR) over time (i.e., 6 and 12 months) and the impact of the treatment groups (CP, MP1, MP2). RESULTS: At 12 months, median BOP and PD reductions amounted to -58.33% and - 1.16 mm in the MP1, to -62.50% and -1.95 mm in the MP2, and to -66.67% and -0.83 mm in the CP groups, respectively. The associated MR changes ranged between 0.00 and 0.08 mm. The survival rates were 100% in all groups. CONCLUSIONS: All treatment protocols were associated with short-term improvements in the clinical parameters investigated.

Esthetic and clinical outcomes after immediate placement and restoration: Comparison of two implant systems in the anterior maxilla-A cross-sectional study.

AIM: To assess the esthetic and clinical performance of a novel self-tapping implant system for single-tooth restorations in the esthetic zone after immediate placement and provisionalization. MATERIALS AND METHODS: This cross-sectional study included 52 patients contributing a total of 52 immediately placed and restored implants with ≥12 months after functional loading, comparing two different implant systems: Straumann® BLX (Institut Straumann AG, Basel, Switzerland; 25 patients) and Ankylos® (Dentsply Sirona, Hanau, Germany; 27 patients). As the primary outcome measure, peri-implant tissue esthetics were assessed by means of pink esthetics score (PES) rated by three independent clinicians. Moreover, as secondary outcome measures, the peri-implant tissue health was assessed by means of bleeding on probing, probing depth, and suppuration. Apart from that, the modified plaque index, keratinized mucosa width, and the presence of mucosal recessions were also assessed. When clinical signs suggested the possibility of peri-implantitis, radiographs were indicated to assess progressive bone loss. RESULTS: The mean PES ratings were 12.10 ± 1.10 for Ankylos versus 11.2 ± 1.86 for BLX, both achieving good esthetic results without significant differences (p = 0.143). There were no differences among most clinical parameters (plaque, bleeding on probing, probing depth, peri-implant mucosal recession), although peri-implant mucositis was present in one-third of the cases. The inter-rater agreement on esthetics was not significant (p < 0.250). CONCLUSION: Within the limitations of the present study, it was concluded that the use of either BLX or Ankylos implant systems was associated to comparable peri-implant health and good pink esthetic outcomes during immediate implantation and restoration protocols, for at least 12 months.

Surgical interventions for the treatment of peri-implantitis.

BACKGROUND: Peri-implantitis constitutes one of the most frequent late dental implant complications. The disease is initiated by bacterial infection; therefore, anti-infective peri-implantitis treatment strategies are required to arrest the progressive marginal bone loss and maintain the affected implant in function. Although nonsurgical treatment strategies appear to be of limited predictability, treatment outcomes have been frequently improved following surgical interventions. PURPOSE: The present narrative review describes various surgical peri-implantitis treatment modalities, with respect to their indications, performance, and effectiveness. MATERIALS AND METHODS: The present narrative review considered the most relevant studies in the field published in the English language. RESULTS: Surgical peri-implantitis treatment approaches can be categorized as nonreconstrucive therapy, reconstructive therapy, and combined therapy (ie, reconstructive and resective therapy). In addition to disease resolution, reconstructive approaches also seek to regenerate the bone defect and achieve reosseointegration. CONCLUSIONS: The severity of the disease, the regenerative potential of the defetc and esthetic demands of the patient are the factors determining the surgical peri-implantitis treatment modality.

Clinical and Esthetic Evaluation Following Immediate Implant Placement and Restoration with Platform- Switched Morse Taper Implants in the Esthetic Zone: A Cross-Sectional Study.

Immediate implant placement with immediate restoration in the esthetic zone is a standardized protocol that aims to satisfy the patient with an immediate, esthetic rehabilitation. This study evaluated clinical and esthetic outcomes following immediate implant placement and provisionalization over a medium- to long-term period. A total of 57 implants in 44 patients were included in the present cross-sectional study, with a follow-up period of 3.97 ± 2.03 years. Surgical and prosthetic treatments were performed according to a standardized protocol. Clinical outcomes (modified Plaque Index, bleeding on probing, probing depth [PD], keratinized mucosa, mucosal recession [MR], and pink esthetic score [PES]) were evaluated during follow-up. Peri-implant tissue health was assessed based on the established case definitions. The mean PES value at the final control examination (mean PES follow-up time: 3.79 ± 1.85 years) was 12.06, the mean PD was 2.52 ± 0.88 mm, and mean MR was 0.03 ± 0.13 mm. No suppuration, pain, or implant or prosthetic failures were reported. The prevalence rates of mucositis and peri-implantitis were 45.5% and 0%, respectively. Immediate implant placement and restoration was associated with peri-implant tissue stability and esthetics over medium- and long-term follow-up periods.

Volumetric tissue changes following combined surgical therapy of peri-implantitis: A 2-year follow-up analysis. A prospective case series.

AIM: To assess volumetric tissue changes following combined surgical therapy of peri-implantitis over a follow-up period of 24 months. MATERIALS AND METHODS: A total of 20 patients (n = 28 implants) were diagnosed with peri-implantitis and underwent access flap surgery, implantoplasty, and augmentative therapy at intrabony components (ie, combined therapy) using a natural bone mineral and a native collagen membrane. The peri-implant region of interest (ROI) was intraorally scanned pre-operatively (S0), and after 12 (S3) and 24 (S4) months. Digital files were superimposed for the assessment of volumetric changes between the referred time points. The change in thickness was assessed at a standardized ROI, segmented into two equidistant sections (ie, marginal and apical). RESULTS: Peri-implant tissues exhibited a nonsignificant mean thickness loss of 0.16 (95% CI: -4 to 0.06) and 0.17 mm (95% CI: -0.05 to 0.4) at S3 and S4, respectively. S0-S3 dimensional thickness changes at marginal and apical areas were -0.24 (95% CI: -0.48 to 0.002) and -0.19 mm (95% CI: -0.36 to -0.2), respectively. Dimensional changes from S0 to S4 amounted to -0.22 mm (95% CI: -0.46 to 0.02) and -0.07 mm (95% CI: -0.09 to 0.2), respectively. The thickness changes at marginal and apical ROIs were significant from S0 to S3. Clinical parameters (ie, plaque index, bleeding on probing, and probing depth) significantly improved over the 24-month follow-up period. Linear regression analyses revealed no significant association between baseline bone loss (%), width of keratinized mucosa, and mucosal recession scores and thickness changes. CONCLUSIONS: Peri-implant tissues revealed minor volumetric changes at 12 and 24 months after combined surgical therapy.

Influence of macrophage polarization on the effectiveness of surgical therapy of peri-implantitis.

PURPOSE: To evaluate the influence of macrophage expression and polarization on the effectiveness of surgical therapy of peri-implantitis over a 6 month follow-up. METHODS: A total of fourteen patients (n = 14 implants) diagnosed with peri-implantitis underwent access flap surgery, granulation tissue removal, implantoplasty, and augmentation at intra-bony components using a natural derived bone mineral and application of a native collagen membrane during a standardized surgical procedure. Granulation tissue biopsies were prepared for immunohistochemical characterization and macrophage polarization assessment. M1 and M2 phenotype expression was identified and quantified through immunohistochemical markers and histomorphometrical analyses. Clinical evaluation and data collection were performed initially and after a healing period of 6 months. Statistical analyses were performed to associate infiltrated area, macrophage, and M1/M2 phenotype influence on peri-implant tissue healing parameters after a 6-month follow-up. RESULTS: Mean infiltrated compartment (ICT) values occupied a total percentage of 70.3% ± 13.0 in the analyzed granulation tissue biopsies. Macrophages occupied a mean area of 15.3% ± 7.0. M1 and M2 phenotypes were present in 7.1 ± 4.1% and 5.5 ± 3.7%, respectively. No statistically significant difference was observed between M1 and M2% expression (p = 0.16). The mean M1/ M2 ratio amounted to 1.5 ± 0.8. Surgical therapy was associated with statistically significant reductions in mean bleeding on probing (BOP), probing depth (PD) and suppuration (SUPP) scores at 6 months (p < 0.05). Linear regression analyses revealed a significant correlation between macrophage expression (CD68%) and changes in PD scores and M1 (%) expression and changes in mucosal recession (MR) scores at 6 months. CONCLUSIONS: The present data suggest that macrophages might influence peri-implant tissue healing mechanisms following surgical therapy of peri-implantitis over a short-term period. Particularly, changes in PD and MR scores were statistically significantly associated with macrophage expression and phenotype.

The prevalence of peri-implant diseases around subcrestally placed implants: A cross-sectional study.

OBJECTIVES: To evaluate the prevalence of peri-implant health, peri-implant mucositis or periimplantitis for subcrestally placed implants (1-3 mm) on the short-, medium- and long term. MATERIAL AND METHODS: Two hundred patients were enrolled in this cross-sectional study that were treated and screened during regular maintenance visits at one university center. A total of 657 implants were evaluated. Peri-implant health and diseases were assessed according to predefined case definitions. Binary logistic regression was used to assess the correlation with local and systemic factors. RESULTS: After a median function time of 9.36 ± 6.44 years (range: 1-26 years), the prevalence of peri-implant mucositis and peri-implantitis was 66.5% and 15.0%, at the patient level, corresponding to 62.6% and 7.5%, at the implant level, respectively. Peri-implantitis was significantly associated with patients' history of periodontitis (odds ratio, OR 5.33). CONCLUSION: Peri-implant diseases were a common finding around subcrestally placed implants.

The influence of soft-tissue volume grafting on the maintenance of peri-implant tissue health and stability.

BACKGROUND: To investigate the influence of soft-tissue volume grafting employing autogenous connective tissue graft (CTG) simultaneous to implant placement on peri-implant tissue health and stability. MATERIAL AND METHODS: This cross-sectional observational study enrolled 19 patients (n = 29 implants) having dental implants placed with simultaneous soft-tissue volume grafting using CTG (test), and 36 selected controls (n = 55 implants) matched for age and years in function, who underwent conventional implant therapy (i.e., without soft-tissue volume grafting). Clinical outcomes (i.e., plaque index (PI), bleeding on probing (BOP), probing depth (PD), and mucosal recession (MR)) and frequency of peri-implant diseases were evaluated in both groups after a mean follow-up period of 6.15 ± 4.63 years. RESULTS: Significant differences between test and control groups at the patient level were noted for median BOP (0.0 vs. 25.0%; p = 0.023) and PD scores (2.33 vs. 2.83 mm; p = 0.001), respectively. The prevalence of peri-implant mucositis and peri-implantitis amounted to 42.1% and 5.3% in the test and to 52.8% and 13.9% in the control group, respectively. CONCLUSION: Simultaneous soft-tissue grafting using CTG had a beneficial effect on the maintenance of peri-implant health.

Macrophage polarization in peri-implantitis lesions.

OBJECTIVES: To immunohistochemically characterize and correlate macrophage M1/M2 polarization status with disease severity at peri-implantitis sites. MATERIALS AND METHODS: A total of twenty patients (n = 20 implants) diagnosed with peri-implantitis (i.e., bleeding on probing with or without suppuration, probing depths ≥ 6 mm, and radiographic marginal bone loss ≥ 3 mm) were included. The severity of peri-implantitis was classified according to established criteria (i.e., slight, moderate, and advanced). Granulation tissue biopsies were obtained during surgical therapy and prepared for immunohistological assessment and macrophage polarization characterization. Macrophages, M1, and M2 phenotypes were identified through immunohistochemical markers (i.e., CD68, CD80, and CD206) and quantified through histomorphometrical analyses. RESULTS: Macrophages exhibiting a positive CD68 expression occupied a mean proportion of 14.36% (95% CI 11.4-17.2) of the inflammatory connective tissue (ICT) area. Positive M1 (CD80) and M2 (CD206) macrophages occupied a mean value of 7.07% (95% CI 5.9-9.4) and 5.22% (95% CI 3.8-6.6) of the ICT, respectively. The mean M1/M2 ratio was 1.56 (95% CI 1-12-1.9). Advanced peri-implantitis cases expressed a significantly higher M1 (%) when compared with M2 (%) expression. There was a significant correlation between CD68 (%) and M1 (%) expression and probing depth (PD) values. CONCLUSION: The present immunohistochemical analysis suggests that macrophages constitute a considerable proportion of the inflammatory cellular composition at peri-implantitis sites, revealing a significant higher expression for M1 inflammatory phenotype at advanced peri-implantitis sites, which could possibly play a critical role in disease progression. CLINICAL RELEVANCE: Macrophages have critical functions to establish homeostasis and disease. Bacteria might induce oral dysbiosis unbalancing the host's immunological response and triggering inflammation around dental implants. M1/M2 status could possibly reveal peri-implantitis' underlying pathogenesis.

The influence of simultaneous lateral grafting on clinical outcomes following one-stage implant placement: a cross-sectional analysis.

BACKGROUND: To investigate the influence of lateral bone augmentation procedures performed simultaneously with implant placement on peri-implant health or disease. MATERIAL AND METHODS: A total of 232 patients showing the same type of a two-piece implant placed either simultaneously with lateral bone grafting using a bovine bone mineral and a native collagen membrane (n = 291 implants; test group) or at pristine bone sites without lateral bone grafting (n = 283 implants; control group) were enrolled in this cross-sectional analysis. Clinical outcomes (i.e., modified plaque index (mPI), bleeding on probing (BOP), probing depth (PD), and mucosal recession (MR)), and the frequency of peri-implant disease were evaluated after a mean follow-up period of 9.97 ± 6.55 years. RESULTS: No differences were found between the patients in the test and control groups for any of the parameters investigated (i.e., mPI, BOP, PD, and MR). For the implants in both groups, PD values of 4-6 mm were more frequently noted in the upper jaw. A significant correlation between increased PD values and a larger implant diameter was noted for test implant sites. A KM of < 2 mm was associated with increased MR values in both groups. The prevalence of peri-implant mucositis and peri-implantitis was 68% and 5% for the patients in the test group and 61% and 10% in the control group, respectively. CONCLUSIONS: Simultaneous lateral grafting was associated with peri-implant tissue health and stability.

3D-printed patient individualised models vs cadaveric models in an undergraduate oral and maxillofacial surgery curriculum: Comparison of student's perceptions.

BACKGROUND: Recent advances in 3D printing technology have enabled the emergence of new educational and clinical tools for medical professionals. This study provides an exemplary description of the fabrication of 3D-printed individualised patient models and assesses their educational value compared to cadaveric models in oral and maxillofacial surgery. METHODS: A single-stage, controlled cohort study was conducted within the context of a curricular course. A patient's CT scan was segmented into a stereolithographic model and then printed using a fused filament 3D printer. These individualised patient models were implemented and compared against cadaveric models in a curricular oral surgery hands-on course. Students evaluated both models using a validated questionnaire. Additionally, a cost analysis for both models was carried out. P-values were calculated using the Mann-Whitney U test. RESULTS: Thirty-eight fourth-year dental students participated in the study. Overall, significant differences between the two models were found in the student assessment. Whilst the cadaveric models achieved better results in the haptic feedback of the soft tissue, the 3D-printed individualised patient models were regarded significantly more realistic with regard to the anatomical correctness, the degree of freedom of movement and the operative simulation. At 3.46 € (compared to 6.51 €), the 3D-printed patient individualised models were exceptionally cost-efficient. CONCLUSIONS: 3D-printed patient individualised models presented a realistic alternative to cadaveric models in the undergraduate training of operational skills in oral and maxillofacial surgery. Whilst the 3D-printed individualised patient models received positive feedback from students, some aspects of the model leave room for improvement.

Incidence and prevalence of peri-implantitis and peri-implant mucositis 17 to 23 (18.9) years postimplant placement.

PURPOSE: To evaluate the prevalence of peri-implantitis (PI) and peri-implant mucositis (PM) in a long-term follow-up with comparison among different PI and PM definitions, and to report on the incidence of PI. MATERIALS AND METHODS: In a retrospective clinical study five different PI and PM definitions were applied onto a population with 274 implants 17 to 23 years postimplant placement. Recommendations by the Eighth European Workshop on Periodontology (EWOP) were used as base reference. Clinical and radiological measurements were considered. Risk factors were evaluated in a regression analysis. RESULTS: After an average observation period of 18.9 years, 40.1% of the implants were diagnosed with PM and 15.0% with PI (Eighth EWOP). PI incidence reached 7.9% on implant level and 13.2% on patient level. Implants diagnosed with PI and progressive bone loss displayed exceptionally vertical bone defect configuration (BDC). Diabetes mellitus, smoking, regular maintenance, or a former periodontal infection did not show significant influence on the prevalence of peri-implant diseases. Patients with bruxism displayed significantly less PM and PI. CONCLUSIONS: Vertical BDC seems to correspond with active PI, wherefore we estimate such a defining factor of importance. Diagnosis of PM and evaluation of probing pocket depths might be only of descriptive interest as they could lead to false-positive results.

Decision-making in closure of oroantral communication and fistula.

After removal of a dental implant or extraction of a tooth in the upper jaw, the closure of an oroantral fistula (OAF) or oroantral communication (OAC) can be a difficult problem confronting the dentist and surgeon working in the oral and maxillofacial region. Oroantral communication (OAC) acts as a pathological pathway for bacteria and can cause infection of the antrum, which further obstructs the healing process as it is an unnatural communication between the oral cavity and the maxillary sinus. There are different ways to perform the surgical closure of the OAC. The decision-making in closure of oroantral communication and fistula is influenced by many factors. Consequently, it requires a combination of knowledge, experience, and information gathering. Previous narrative research has focused on assessments and comparisons of various surgical techniques for the closure of OAC/OAF. Thus, the decision-making process has not yet been described comprehensively.The present study aims to illustrate all the factors that have to be considered in the management of OACs and OAFs that determine optimal treatment.