Clark M. Stanford, DDS, PhD, MHA, University of Iowa

Mingfu Ye/Wenjun Liu/Javier Calatrava/Hom-Lay Wang/Wen-Xia Huang

Purpose:
To examine whether mandibular overdentures supported by a single implant vs two implants have similar clinical outcomes, especially pertaining to implant survival, marginal bone loss (MBL), and prosthetic complications.

Materials and Methods:
A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted. Scientific databases (PubMed, Embase, Scopus, Web of Science, and Cochrane Library) were searched from inception until October 2024. These databases were searched for RCTs comparing single- implant– and two- implant–supported mandibular overdentures that reported implant failures, MBL, and prosthetic complications.

Results:
Eleven RCTs were included. The meta-analysis showed reduced implant failure rates with single implants at 1 year (OR: 0.33; 95% CI: 0.10, 1.15; I2 = 0%) and 5 years (OR: 0.11; 95% CI: 0.01, 2.16), but the results were not statistically significant. However, pooled subgroup analyses of studies with a follow-up period of 2 to 3 years indicated a significantly reduced implant failure rate with a single implant compared to two implants (OR: 0.12; 95% CI: 0.03, 0.54; I2 = 0%). No significant differences between the implant failure rates were observed between the two groups based on implant loading protocols. Meta-analysis also showed that there were no significant differences in the risk of MBL between single- and two-implant groups (MD: –0.15; 95% CI: –0.31, 0.01; I2 = 43%). The pooled analysis also showed that the risk of overdenture fracture, relining, and metal housing reattachment did not differ significantly between single- and two-implant groups.

Conclusions:
Evidence from a limited number of RCTs, mainly with small sample sizes, indicates that single- implant–supported mandibular overdentures may have a tendency to cause implant failures at a lower rate than two- implant–supported mandibular overdentures. The risk of MBL and prosthetic complications may not differ between the treatment modalities. Int J Oral Maxillofac Implants 2026;41:433–442. doi:10.11607/jomi.11358

Jennifer Duffy, DMD, MDSc/Ajay Dhingra, BDS, MSD/Satoko Ono Rubin, DMD, MDSc/Gian Pietro Schincaglia, DDS, PhD/Kelin Zhong, PhD4/Sejal Thacker, DDS, MDSc

Purpose:
To evaluate the clinical and radiographic outcomes of two implants placed using either an immediate loading (IL) or delayed loading (DL) protocol to support a nonsplinted, Locator-retained mandibular overdenture.

Materials and Methods:
Twelve eligible patients were enrolled, with six in the IL group and six in the DL group. Clinical and standardized radiographic examinations were conducted to assess implant survival and peri-implant hard and soft tissue health. Patient reported outcomes (PROs) were collected, and the incidence and nature of prosthetic complications were documented.

Results:
The data for the 5-year follow-up of the randomized controlled trial (RCT) were reported in a previous publication. No statistically significant difference in radiographic bone levels (ΔRBL) was observed between IL and DL groups during the 5- to 12-year or 0- to 12-year intervals. One implant was lost in the DL group in the 5- to 12-year period, resulting in a cumulative implant survival rate (CSR) of 96% for DL and 100% for IL at 12 years. At the 12-year follow-up, no significant differences were observed between IL and DL groups with respect to clinical outcomes such as probing pocket depth (PPD), plaque score (PS), keratinized tissue width (KTW), and apical migration of the free gingival margin (GM). PROs related to patient comfort and satisfaction were similar in the IL and DL groups. Major prosthetic complications occurred in 50% of patients, while 92% experienced at least one minor prosthetic issue. A temporal trend of increased radiographic bone loss, decreased KTW, and increased apical migration of the GM from baseline to 12 years was noted in both the IL and DL groups.

Conclusions:
Both IL and DL protocols demonstrated comparable long-term patient comfort, patient satisfaction, and clinical and radiographic performance when applied to two nonsplinted, Locator-retained implants supporting a mandibular overdenture. Within the limitations of the present investigation, IL may represent a reliable and potentially favorable treatment approach for mandibular overdentures in appropriately selected cases. Significant prosthetic complications were noted in both groups, which highlights the importance of regular recall and prosthetic maintenance for long-term success. Int J Oral Maxillofac Implants 2026;41:443–450. doi: 10.11607/jomi.11394

İbrahim Macit, DDS/Burcu Sengüven Toközlü, DDS, PhD/Mehmet Zahit Adışen, DDS, PhD/Sara Samur Ergüven, DDS, PhD/İsmail Doruk Koçyigit, DDS, PhD/Umut Tekin, DDS, PhD

Purpose:
To evaluate the histologic and radiologic effects of autologous blood (AB), advanced platelet-rich fibrin (A-PRF), and a graftless approach in sinus floor elevation supported by a resorbable membrane and ultrasonic-activated pin system.

Materials and Methods:
A total of 21 sinus floor elevation procedures were performed in 11 New Zealand rabbits that were divided into three groups. Each group planned to include seven maxillary sinus regions. Resorbable membranes and ultrasonic-activated pins (SonicWeld Rx, KLS Martin) were used to support the elevated sinus floor in all groups. After elevation of the sinus floor, bone defects were supported with either AB (Group 1), A-PRF (Group 2), or no biomaterial (control; Group 3). The rabbits were sacrificed 8 weeks after surgery. Specimens were obtained from the upper and lower regions of the sinuses. Radiologic and histologic examinations were performed on all samples. The radiologic examination evaluated new bone formation based on density difference (grayscale [GS]) in axial, coronal, and sagittal planes of CBCT sections. Histologic evaluation was performed by analyzing new bone tissue percentage/score, inflammation, and fibrous tissue parameters.

Results:
In the radiologic evaluation, the differences in GS values obtained in Group 3 in all planes were significantly lower than in Group 1 and Group 2, indicating significantly higher bone formation in the control group (P < .05). In the histologic evaluation, the percentage and score of newly formed bone were higher for Group 3; however, that difference was only significant between Group 3 and Group 1 for the specimens taken from the upper regions (P = .005 and P = .018, respectively). Fibrous tissue formation was lower in Group 3; the difference was significant between Group 3 and Group 1 for the specimens taken from the upper regions (P = .037). Inflammation values were similar between the groups.

Conclusions:
New bone formation after graftless sinus floor elevation was associated with more successful outcomes than the groups using AB or A-PRF in terms of histologic and radiologic parameters. Int J Oral Maxillofac Implants 2026;41:451–458. doi: 10.11607/jomi.11391

Hongseok An, DDS, MSD/Molly Tess McCoy, BS/Despoina Bompolaki, DDS, MS

Purpose:
To evaluate intraoral scan (IOS) accuracy for implants placed in edentulous mandibles when intraoral resin markers are used. Two commonly used intraoral scanners were assessed under simulated oral mucosa conditions to determine the effect of resin markers on IOS accuracy.

Materials and Methods:
A mandibular study model with four implants and simulated unattached mucosa was fabricated. The model was scanned using two intraoral scanners (TRIOS 4, 3Shape; Primescan, Dentsply Sirona), both with and without flowable composite resin markers applied between scan bodies. A total of 30 scans were captured per scanner (15 without markers, 15 with markers), resulting in four IOS groups: TR (TRIOS 4), PS (Primescan), TRmark (TRIOS 4 with markers), and PSmark (Primescan with markers). Indirect digitization was performed via conventional impressions, stone model fabrication, and laboratory scanning (IND group). A reference scan (REF) was obtained using a high-accuracy laboratory scanner (E4, 3Shape). All scan files were analyzed in Geomagic Control software. Root-mean-square (RMS) values were calculated for trueness and precision. Kruskal-Wallis test was used to evaluate group differences, followed by pairwise comparisons (α = .05).

Results:
Trueness analysis revealed significant differences between groups (P < .001). IND exhibited the highest trueness, followed by TRmark, PSmark, and PS, while TR showed the lowest trueness. Precision analysis indicated significant influence of the scanning method (P < .001). PSmark, TRmark, and IND showed the highest precision, and TR had the lowest precision. The addition of resin markers significantly improved both trueness and precision for TRIOS 4.

Conclusions:
Indirect digitization remains the most accurate method for full-arch implant scanning. Scanner type affects IOS accuracy, with Primescan demonstrating higher accuracy than TRIOS 4 without resin markers. Resin markers significantly improved IOS accuracy, particularly for TRIOS 4, where both trueness and precision increased. The clinical implications are that while conventional impressions with splinted impression copings remain the gold standard, IOS accuracy for edentulous mandibular arches can be significantly improved with the use of simple resin markers, offering a practical and cost-effective enhancement to digital workflows. The use of resin markers is a viable technique to enhance scan reliability without requiring additional specialized equipment. Int J Oral Maxillofac Implants 2026;41:459–466. doi: 10.11607/jomi.11396

Abdulrahman S. Aldakhili, BDS/Majd A. Alotaibi, DDS/Abdulmohsen Alsalman, BDS, MSD/Yousif A. Al-Dulaijan, BDS, MSD, PhD/Haidar A. Alalawi, BDS, MSD/Ashwin C. Yermal, BDS, MSD/Ahmad M. Al-Thobity, BDS, MSD

Purpose:
To assess and compare the marginal gap and screw loosening, and their relationship, in three-unit implantsupported fixed partial dentures (ISFPDs).

Materials and Methods:
Fifty frameworks were fabricated from zirconia (Zir), cobalt-chromium (CoCr), titanium (Ti), polyetheretherketone (PEEK), and polyetherketoneketone (PEKK) (n = 10 each) using CAD/CAM technology on a standardized two-implant model. Vertical marginal discrepancies were measured using scanning electron microscopy at four points per framework/abutment interface. Screw loosening was assessed using a digital torque device. Data were analyzed using IBM SPSS software with a significance level of P < .05.

Results:
The marginal mean gap differed significantly between the groups across all four surfaces (P < .001). Overall, PEEK had the smallest marginal mean gap (67.22 ± 15.55 μm), followed by Ti (105.65 ± 30.52 μm), PEKK (106.80 ± 34.58 μm), and Zir (115.62 ± 22.02 μm), with CoCr showing the largest gap (176.87 ± 88.34 μm). In screw loosening tests, PEKK demonstrated the lowest values in both molar (0.44% ± 0.73%) and premolar (0.06% ± 1.40%) abutments, whereas PEEK showed the highest values in molar abutments (1.03% ± 1.21%) and CoCr showed the highest values in premolar abutments (2.15% ± 1.29%). No significant correlation was observed between the marginal gap and screw loosening (P > .05).

Conclusions:
The findings of this study emphasize the critical role of material selection in the clinical performance of ISFPDs. PEEK offers superior marginal adaptation, potentially reducing microleakage, whereas PEKK enhances screw stability, minimizing prosthetic complications. Int J Oral Maxillofac Implants 2026;41:467–474. doi: 10.11607/jomi.11390

Busra Terzioglu, PhD, DDS/Ahu Uraz Corekci, DDS, PhD/Sertac Sariyer, DDS, PhD/Seyma Eken, DDS, PhD/Berceste Guler Ayyildiz, DDS, PhD

Purpose:
To compare pre-clerkship and clerkship dental student groups to evaluate the effects of undergraduate education and clinical clerkship on dental student perspectives on implant treatment and education.

Materials and Methods:
This survey study was conducted on all dentistry students at two universities in Turkey. Data were collected between June and July 2024 through a digital survey containing various questionnaires regarding student knowledge, attitudes, perspectives, and future plans regarding dental implant treatment and education. All surveys were validated and reliable, with Turkish validity confirmed. Survey data compared responses from pre-clerkship and clerkship groups.

Results:
A total of 394 students participated in this study. The overall response rate to the survey was 43.7%. Of the participants, 55.8% were in the pre-clerkship group and 44.2% were in the clerkship group. Statistically significant relationships were determined for both self-assessment knowledge and attitude levels between the pre-clerkship and clerkship groups (P < .05). The pre-clerkship group often expressed uncertainty, stating phrases like “no knowledge,” “I cannot estimate,” or “no opinion,” whereas the clerkship group demonstrated greater self-confidence. Both groups agreed on the necessity of undergraduate implant education, but the pre-clerkship group (71.9%) preferred the inclusion of clinical practice education more often than the clerkship group (57.8%).

Conclusions:
This study indicates that a combination of theoretical education and clinical observation in the undergraduate curriculum enhances student perception of implant treatment and education. However, there is still a need to improve theoretical education and incorporate practical application into the curriculum to achieve optimal outcomes. Int J Oral Maxillofac Implants 2026;41:475–486. doi: 10.11607/jomi.11403

Massimo Del Fabbro, MSc, PhD/Sourav Panda, MDS, PhD/Margherita Tumedei, DDS, PhD/Renzo Guarnieri, DDS/Tejas Pande,MDS/Gianluca Colapinto, MD, OMFS, DDS/Massimo Albanese, MD, OMFS/Tiziano Testori, MD, DDS, MSc

Purpose:
To assess the diagnostic accuracy and clinical usefulness of active matrix metalloproteinase-8 (aMMP-8) for the diagnosis of peri-implantitis in patients with dental implants.

Materials and Methods:
The review protocol was registered in PROSPERO. A comprehensive search was conducted in PubMed, Embase, and Scopus up to October 31, 2025, supplemented by manual and gray literature searches. Studies assessing aMMP-8, a collagenase released during active inflammation, in peri-implant sulcular fluid (PISF) for the diagnosis of peri-implantitis were included. Data on biomarker detection methods, diagnostic performance—in terms of sensitivity, specificity, accuracy, and the Area Under the Receiver Operating Characteristic Curve (ROC-AUC)—and correlations with clinical indices were extracted. Eight studies that were published between 2016 and 2025, with a total of 506 patients (293 with healthy peri-implant tissues or mucositis and 213 diagnosed with peri-implantitis), met the inclusion criteria. Study quality was assessed using the Newcastle-Ottawa Scale (NOS). A qualitative analysis was conducted by compiling a summary of findings for all included studies.

Results:
Study quality was generally high (mean NOS score: 7.1 ± 0.6). Seven studies assessed aMMP-8 using pointof- care lateral flow immunoassay and one used immunoassay after PISF freezing and thawing. The aMMP-8 levels were consistently higher in sites with peri-implantitis compared to sites with mucositis and healthy sites. Reported diagnostic sensitivity for peri-implantitis ranged 70% to 100%, specificity from 74.1% to 100.0%, and ROC-AUC from 0.80 to 0.88. Due to heterogeneity across included studies, no meta-analysis was performed.

Conclusions:
aMMP-8 in PISF represents a noninvasive biomarker with a high diagnostic accuracy for early detection of peri-implantitis. Standardization of cutoff thresholds and longitudinal validation are required before routine clinical integration. Int J Oral Maxillofac Implants 2026;41:487–499. doi: 10.11607/jomi.11327

Alex Sarpong, BDS, DMD, MS/Ghadeer Thalji, DDS, PhD/Bin Yang, DMD, MS, PhD/Sandra Al-Tarawneh, DDS, MS

Purpose:
To evaluate the survival rate of implants and prostheses as well as the complications associated with implant overdentures (IODs) for edentulous maxillae retained by nonsplinted implants.

Materials and Methods:
A total of 76 patients who had received and retained maxillary IODs for at least 6 months between 2006 and 2021 were included in the study. A comprehensive review of patient charts was done to assess the implant and prosthodontic outcomes in these patients. Descriptive data were compiled, and statistical analysis of each variable was performed. Correlation between categorical variables was done using Spearman’s rank correlation with a two-tailed significance test.

Results:
Ten implants failed in 7 patients, resulting in an implant survival rate of 96.9% following prosthesis delivery. The prosthesis survival rate was 78.9%, with 16 of 76 patients needing a remake of their prosthesis. The most common technical complication was tooth debonding, accounting for 21.2% of technical complications. A correlation analysis found that certain opposing dentitions contributed to an increase in the number of technical complications associated with the maxillary IODs (r[75] = 0.24) (P < .05).

Conclusions:
Maxillary IODs with nonsplinted implants showed high implant survival rates comparable to those reported in previous studies. However, the prosthesis survival rate was lower than reported in the literature for maxillary IODs with splinted or nonsplinted designs. It is recommended that the patient’s opposing dentition be sufficiently considered during treatment planning to reduce overloading factors and resultant technical complications. Int J Oral Maxillofac Implants 2026;41:500–506. doi: 10.11607/jomi.11201

Xuejing Hu, MM/Ju Sun, BD

Purpose:
To compare the clinical outcomes of minimally invasive extraction with immediate implantation (MIEII) to traditional extraction with delayed implantation (TEDI) in dental procedures.

Materials and Methods:
A comprehensive literature search was conducted across multiple databases. Twelve randomized controlled trials involving 934 patients were included. The primary outcomes assessed were Pink Esthetic Score (PES), White Esthetic Score (WES), implant success rate, patient satisfaction, and incidence of complications. Standardized mean difference (SMD) and risk ratio (RR) with 95% confidence intervals (CIs) were calculated using random effects models.

Results:
MIEII significantly improved PES (SMD = 1.60; 95% CI: 0.87, 2.33) and WES (SMD = 2.08; 95% CI: 1.64, 2.53) compared to TEDI. No significant differences were found in implant success rates (RR = 1.00; 95% CI: 0.89, 1.14) or patient satisfaction (RR = 1.11; 95% CI: 0.94, 1.31). However, MIEII demonstrated a lower incidence of complications (RR = 0.40; 95% CI: 0.19, 0.86).

Conclusions:
MIEII offers superior esthetic outcomes and reduced incidence of complications compared to TEDI while maintaining comparable implant success rates and patient satisfaction. These findings suggest that MIEII may be a preferable approach for suitable cases, particularly in esthetically demanding areas. Int J Oral Maxillofac Implants 2026;41:507–515. doi: 10.11607/jomi.11377

Cheng-Han Hsieh, DDS/Pe-Yi Kuo, DDS/Meng-Yao Chiu, DDS/Cho-Ying Lin, DDS

Purpose:
To evaluate the effectiveness of different alveolar ridge preservation (ARP) techniques by means of 2D and 3D radiographic analysis.

Materials and Methods:
The retrospective study included three different ARP approaches: (1) half-grafted technique covered with a collagen membrane (TestC, n = 6); (2) half grafted technique covered with a nonresorbable dense polytetrafluoroethylene (dPTFE) membrane (TestD, n = 8); and (3) full-grafted technique covered with a collagen membrane (Control, n = 13). The radiographic evaluation included linear, area, and volume changes at multiple time points throughout the 12-month follow-up: before tooth extraction, 6 months after ARP, during implant surgery, and 6 months after loading. The correlation between baseline socket conditions and radiographic outcomes was also investigated.

Results:
Among the different ARP strategies, significantly more horizontal reduction (change in horizontal ridge width, ΔHRW) was observed in the half-grafted groups (men of both groups) 6 months after ARP (ΔHRW1—half-grafted: –2.45 ± 0.96 mm; full-grafted: –1.21 ± 0.98 mm, P = .002; ΔHRW3—half-grafted: –1.49 ± 1.34 mm; full-grafted: –0.27 ± 0.68 mm, P = .002; ΔHRW5—half-grafted: –0.46 ± 0.27 mm; full-grafted: –0.16 ± 0.41 mm, P = .033). Following the removal of poorly attached graft material at implant surgery, the half-grafted groups showed significantly more area reduction (ΔA%) (half-grafted: –11.53% ± 12.56%; full-grafted: –6.11% ± 4.73%, P = .022). However, there was no intergroup difference in volume change (ΔVo%) (P = .892). All implants presented stable peri-implant health without the presence of peri-implant disease or progressive bone loss, regardless of the ARP technique used. The type of destruction affecting the tooth and the reasons for extraction were not relevant to ridge alteration, while a thin buccal plate was associated with greater reductions in height (P = .02) and area (P = .047).

Conclusions:
Both the half-grafted and fullgrafted techniques showed comparable results in volume analysis and peri-implant health at all time points, but the half-grafted strategy could present more area reduction after graft removal during implant surgery. Additionally, sockets with a buccal plate thinner than 1 mm may experience a compromised effect on ridge preservation. Int J Oral Maxillofac Implants 2026;41:516–526. doi: 10.11607/jomi.11369

Silvio Valdec, DMD/Fabienne A. Bosshard, DMD/Andrea Patrizi, DT/Nadja Naenni, DMD/Adib Al-Haj Husain, DMD

Purpose:
Beta-tricalcium phosphate (β-TCP), a ceramic material renowned for its excellent biocompatibility, is widely used in oral tissue regeneration due to its superior osteoconductive properties. This case report presents the surgical and prosthodontic management, along with 2-year clinical and radiologic follow-ups, of a patient-specific β-TCP scaffold designed using CAD/CAM for the augmentation of a complex maxillary anterior alveolar ridge defect.

Materials and Methods:
A 37-year-old man presented with a malpositioned implant in the anterior maxilla, initially placed during adolescence. Ongoing alveolar ridge growth resulted in increased infraposition, exposed implant surface, and esthetic concerns, which required repeated prosthetic corrections. Implant removal was followed by treatment involving a patient-specific β-TCP scaffold to address both functional and esthetic deficiencies. The scaffold was designed by means of CAD/CAM, providing a tailored solution for bone augmentation. Because the final restoration was planned without an implant-based rehabilitation, a resorbable magnesium screw was chosen as the fixation element to minimize the need for reintervention. Despite a buccal dehiscence that necessitated additional soft tissue grafting, at the 1-year follow-up the scaffolding demonstrated excellent integration and successful prosthetic restoration. The 2-year follow-up still demonstrated successful clinical and esthetic outcomes. However, radiologic findings revealed ambiguous resorption patterns in the scaffold area, prompting concerns about potential complications.

Conclusions:
This case highlights the benefits of using CAD/CAM-based β-TCP scaffolds for complex alveolar ridge augmentation, which offer enhanced predictability and reduced perioperative technical challenges. Despite the complication of soft tissue dehiscence, the long-term clinical outcome was favorable. Further clinical research is necessary to assess the long-term effectiveness and possible limitations of β-TCP scaffolds in regenerative and reconstructive dentistry, particularly regarding resorption patterns and soft tissue integration. Close clinical monitoring is recommended to ensure optimal healing and prevent any adverse effects on the treatment outcome. Int J Oral Maxillofac Implants 2026;41:527–535. doi: 10.11607/jomi.11352

Arvind P. Adapalli, DDS, MS/James Katancik, DDS, PhD/Justin Merritt, PhD/Chandur Wadhwani, DDS, MS

Purpose:
To assess the potential risk of bacterial cross-contamination during analog impression-making for dental implants after disinfection using a conventional spray technique.

Materials and Methods:
Eight patients, of varying ages and both genders, who had undergone dental implant treatment with a total of nine implants were enrolled in this study. Approximately 3 to 4 months after implant placement, clinical and radiographic examinations were conducted, and probing depths and bleeding on probing were recorded. Additionally, salivary flow evaluations were performed. Analog open-tray impressions were made using polyvinyl siloxane material. Once set, each implant impression coping was removed from the implant, and the impression was taken out of the patient’s mouth. The retrieved impression was disinfected on all surfaces, with special attention given to the intaglio surface, impression coping, and screw area, using sodium hypochlorite. After a 10-minute disinfection period, the impression copings were swabbed with sterile paper points and placed into vials of liquid Columbia Broth for bacterial culturing. A new, unused implant impression coping was swabbed as a negative control, and a non-adjacent, non-implant site was swabbed as a positive control. Following incubation at 37ºC for 24 hours, DNA was extracted from the samples that exhibited bacterial growth, and 16S DNA sequencing was performed.

Results:
Out of the nine samples, six showed bacterial growth, with Streptococcus being the most frequently identified genus. Implant sites that exhibited bleeding on probing were also associated with a higher presence of Rothia bacteria. There was also a higher presence of Neisseria bacteria in the group with higher salivary production. No bacterial growth was observed in the positive and negative control samples. No significant differences were found in the samples based on gender, age, or salivary flow.

Conclusions:
Conventional implant impression-making using standard disinfection protocols and guidelines may lead to microbial contamination. Further research is warranted to investigate cross-contamination and disinfection techniques related to dental implant impression materials. Int J Oral Maxillofac Implants 2026;41:536–542. doi: 10.11607/jomi.10352