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

Jan C. Kwan, MESc1

Purpose: To evaluate initial torque values (ITVs) and removal torque values (RTVs) in abutment screw tightening and their impact on torque application at the implant-abutment junction (IAJ) using a biomechanical friction resistance model simulating various bone densities, with and without counter-torquing measures.

Materials and Methods: A total of 60 implant-abutment assemblies were divided into three groups that each simulated different levels of frictional resistance as follows: (1) low: < 30 Ncm; (2) medium: 30 to 40 Ncm; and (3) high: > 40 Ncm. The endpoint for abutment screw tightening was either reaching a preset torque value of 35 Ncm or detecting a change in the implant’s angular position. ITV, RTV, and changes in angular position were recorded. One-way analysis of variance (ANOVA) and post-hoc Tukey tests were
used.

Results: For all frictional resistance groups, abutment screws tightened with a counter-torquing device attained 35 Ncm (P > .05). Abutment screws tightened without a counter-torquing device in low and medium frictional resistance groups were unable to attain 35 Ncm prior to implant rotation. ITVs of abutment screws without counter-torque were not significantly different in the medium and high frictional resistance groups (P > .05) but were significantly different in the low frictional resistance group (P < .001). No significant difference was found for the change in implant angular displacement for all groups (P > .05), regardless of counter-torquing measures; however, a high variance was observed in the low and medium frictional resistance groups.

Conclusions: Under the experimental conditions, counter-torque is important to ensure that the desired torque value is applied to the implant-abutment connection in low frictional resistance. RTV is proportionally related to ITV and can be used to estimate the ITV at the IAJ. Int J Oral Maxillofac Implants 2026;41:171–180. doi: 10.11607/jomi.11322

Mosaad Abdaljawwad Khalifah, DDSc, FDS (RCSEd), MOMS (RCPSGlasg), MOS (RSCEd), Asst FDT (RCSEd)1

Purpose: To present and compare the novel double expansion technique (DET) (Khalifah’s technique) and the ridge splitting technique (RST) in cases of narrow ridges.

Materials and Methods: A total of 40 patients (57 dental implants [DIs]) with narrow ridges were randomly allocated to a control group, which employed the RST, and to a study group, which employed the DET. Secondary stability, marginal bone loss (MBL), keratinized mucosa width (KMW), Plaque Index (PI), bleeding index (BI), and probing depth (PD) were assessed at baseline (time of definitive abutment and temporary crown placement) and then at 3, 6, and 12 months. Pain and the number of analgesic tablets consumed were assessed daily during the first postoperative week.

Results: The study group had lower pain levels during the first 2 days postoperatively and presented with greater primary and secondary stability at baseline and at 3 months. Moreover, patients in that group had less MBL at all time points and greater KMW at 6 and 12 months postoperatively. Otherwise, both groups showed comparable results regarding PI, BI, and BD.

Conclusions: The study group had superior performance, which may be attributed to the lower degree of trauma with the DET. Int J Oral Maxillofac Implants 2026;41:181–188. doi: 10.11607/jomi.11388

Roberto Crespi, MD, DDS1/Giovanni-Battista Menchini-Fabris, DDS, PhD, MSc1,2/Paolo Toti, BSc, DDS1/ Georgios E. Romanos, DDS, PhD, Prof Dr Med Dent3

Purpose: To investigate the remodeling process of hard tissue components in fresh extraction sockets that underwent natural healing followed by localized alveolar split-crest surgery for implant placement.

Materials and Methods: Patients with bone defects in the maxillary esthetic zone, characterized by decreased mineral density around the affected tooth were treated via socket healing without bone substitutes, delayed alveolar splitting, and subsequent implant placement.
Preoperative (baseline: before the stage-one and stage-two surgeries) and postoperative CBCT scans were analyzed to assess changes in bone volume and crestal width. Statistical analysis was performed using nonparametric tests, with a significance level set at P < .05.

Results: A total of 13 incisors were retrospectively evaluated. No major postoperative adverse events were recorded. After 2 years, the implants achieved a 100% survival rate. No episodes of peri-implant mucositis or peri-implantitis were reported. Radiographs taken 3 months after tooth extraction revealed bone mineralization without the use of bone substitutes; however, the volume was insufficient for immediate implant placement. Following tooth extraction, the split procedure, and implant placement (stage-one and stage-two surgeries), total bone volume showed a significant increase (P = .0105) from baseline (919 ± 179 mm3) to the 2-year follow-up (955 ± 176 mm3). Similarly, crestal width demonstrated a significant increase (P = .0012), increasing from 6.1 ± 2.7 mm at baseline to 7.5 ± 2.0 mm at 2 years, with a mean gain of 1.4 ± 1.0 mm due to the split-crest procedure.

Conclusions: After 2 years, the results indicated that natural healing of the extraction socket without the use of bone substitutes, followed by delayed localized alveolar splitting, led to a significant increase in bone volume and preservation of the outermost alveolar bone layer. The observed postextraction site augmentation was concentrated in the esthetic zone. Int J Oral Maxillofac Implants 2026;41:189–196. doi: 10.11607/jomi.11305

Vilton Zimmermann de Souza, DDS, PhD1/Rafael Manfro, DDS, PhD1/Lucas Novaes Teixeira, DDS, PhD1/ Carlos Nelson Elias, DDS, PhD2/Julio Cesar Joly, DDS, PhD1/Elizabeth Ferreira Martinez, DDS, PhD1

Purpose: To assess the effects of anodized prosthetic abutments versus machined abutments on peri-implant connective tissue.

Materials and Methods: Following dental implant placement and osseointegration, custom healing abutments with machined surfaces (G1) and anodized surface treatment (G2) were attached to 28 dental implants. After a soft tissue healing period of approximately 30 days (± 7 days), 5-mm circular biopsy samples were taken from the peri-implant tissue and the area adjacent to the prosthetic abutment. Histologic analysis was conducted on the stained specimens using hematoxylin-eosin (H&E), focusing on parameters such as vascular proliferation as well as the presence of polymorphonuclear and mononuclear cells, collagen fibrils, and reepithelialization. A grading scale from 0 to 3 evaluated the extent of the inflammatory response. Masson’s trichrome staining was used to analyze collagen fiber presence and organization, while immunohistochemical staining assessed the expression of beta-catenin (β-catenin) and Cluster of Differentiation 34 (CD34). The prosthetic abutments were evaluated through scanning electron microscopy and 3D roughness analysis.

Results: Histologic findings revealed that peri-implant tissue adjacent to anodized surfaces exhibited epithelial stratification and a parakeratin layer in the lamina propria. Both groups displayed a typical mononuclear lymphocytic inflammatory infiltrate, but the intensity was significantly higher adjacent to the machined abutment (P < .05). Quantification of blood vessels indicated increased immunopositivity for CD34 in G2 compared to G1 (P < .05). Immunolabeling of β-catenin was detected in the epithelial tissue, showing weak intensity in G1 and strong intensity in G2. The average surface roughness measurements were determined to be 0.097 ± 0.006 μm for G1 and 0.182 ± 0.008 μm for G2.

Conclusions: Anodized surfaces are a promising treatment option and exhibit beneficial effects on peri-implant tissue healing. They play an important role in preserving the epithelial mucosal integrity and functionality near the prosthetic abutment, thereby potentially minimizing the risks of mucositis, peri-implantitis, and implant failure. Int J Oral Maxillofac Implants 2026;41:197–206. doi:10.11607/jomi.11301

Leonello Biscaro, DDS1/Luigi Canullo, DDS, PhD2/ Oriana Spanu, DDS2/Arianna Zuffanti, DDS2/Paolo Pesce, DDS, PhD2/Maria Menini, DDS, PhD2

Purpose: To analyze the clinical complications and compare immediately loaded complete rehabilitations with screwretained versus conometric implant prostheses.

Materials and Methods: A total of 203 patients treated with immediately loaded complete prostheses were evaluated and rehabilitated with a total of 1,356 implants supporting 261 fixed prostheses (65 conometric retention and 196 screw-retained). Implant survival, prosthesis success rate, and technical and biologic complications were evaluated. Chi-square test was performed to evaluate possible statistically significant differences between the two implant prosthesis types.

Results: During the follow-up period (mean = 28.5 months; range = 12 to 80 months), 27 implants failed (2%) and the global prosthetic success rate was 89.3%. No statistically significant differences were found in implant survival and prosthesis success between the two groups. Screw loosening was the most frequent complication (4.2% of cases), followed by chipping or fracture of the veneering material. Prosthesis loss of retention (detachment) occurred in 9.2% of the conometric prostheses.

Conclusions: Both conometric and screw-retained immediately loaded complete rehabilitations presented a high prosthesis success rate and low incidence of complications, with the most frequent complication being screw loosening. Conometric prostheses showed a significantly greater incidence of prosthesis detachment. Int J Oral Maxillofac Implants 2026;41:207–217. doi: 10.11607/jomi.11316

Thiago Rodrigues Lazzari, DDS, MS, PhD1/Victória Clara da Silva Lima, DDS, MS, PhD1/Camilla Magnoni Moretto Nunes, DDS, MS, PhD1/Nidia Castro dos Santos, DDS, MS, PhD2/Felipe Lucas da Silva Neves, DDS, MS, PhD1/Antonio Braulino de Melo Filho, DDS, MS, PhD3/Mauro Pedrine Santamaria, DDS, MS, PhD4/Maria Aparecida Neves Jardini, DDS, MS, PhD1

Purpose: To assess the impact of a subepithelial connective tissue graft (CTG) on soft tissue volume and esthetics around implants placed in esthetically important areas over a 4-year period.

Materials and Methods: A total of 42 participants were divided into two groups: (1) implant and CTG (implant + CTG) (n = 20) and (2) implant only (n = 22). Both groups were evaluated after 48 months using various clinical and radiographic parameters, professional esthetic assessment, patient-centered esthetic evaluation, and quality of life improvement measured by the Oral Health Impact Profile questionnaire with 14 questions (OHIP-14) at 12 and 48 months.

Results: A total of 8 patients were lost to follow-up, leaving 34 patients for evaluation. Intragroup comparison was performed for the following variables: tissue thickness at the buccal aspect (TTb), keratinized tissue width (KTW), and buccal defect (BD). All intragroup comparisons showed no statistical difference (P > .05) in the evaluated periods. However, for proximal bone resorption (PBR), a statistical difference was observed (P < .05). In the intergroup comparison, statistical differences (P < .05) were observed in the variables TTb and BD in the two evaluated periods (12 and 48 months). In the analysis of Pink Esthetic Score/White Esthetic Score (PES/WES) and Jemt index, there were no differences between or within groups in the evaluated periods. Regarding patient-centered measures, there was no difference between the groups in terms of esthetics (visual analog scale), but for OHIP-14, there was an intragroup difference in both groups between 12 and 48 months.

Conclusions: The association of a CTG with dental implants in esthetic areas after a 48-month follow-up led to an increase in TTb; therefore, connective tissue grafting is indicated. However, there were no improvements in BD, PBR, or PES/WES over time. Esthetics and quality of life were similar between the two groups at 4 years posttreatment. Int J Oral Maxillofac Implants 2026;41:218–226. doi: 10.11607/jomi.11269

Soaad Tolba Badawy, PhD1

Purpose: To compare radiographic dimensional changes in postextraction sites treated with spontaneous healing versus
the modified socket shield technique (mSST) without immediate placement using CBCT scans.

Materials and Methods:
This randomized clinical study included 80 patients with a single maxillary anterior tooth that was not restorable. Patients
were divided into two equal groups: (1) the test group, which used the mSST, and (2) the control group, which used
the atraumatic extraction technique with spontaneous healing. CBCT scans were performed at baseline (before or
immediately after extraction) and 6 months postsurgery. Measurements included alveolar ridge width at 1-mm, 3-mm,
and 5-mm levels and buccal and palatal bone plate heights. Following this, implants were placed, and their primary
stability was assessed. The main intervention was the use of the mSST compared to the atraumatic tooth extraction
technique. The primary outcome was the change in buccal bone plate height over a 6-month follow-up period. In addition,
covariates included patient age and sex. Paired t tests and independent t tests were used to evaluate intra- and intergroup
differences, respectively. Statistical significance was set at P < .05.

Results: In the test group, a significant reduction in
palatal wall height was observed (P < .001), while no significant changes were noted in other parameters (P ≥ .05). In the
control group, significant decreases were observed in buccal and palatal plate heights as well as ridge width (P < .05). When
comparing the groups, the test group demonstrated significantly less buccal wall height and ridge width resorption than
the control group (P < .05). However, no significant difference was observed in palatal plate height resorption between
the two groups (P = .507). The test group exhibited significantly higher primary stability rates compared to the control
group (P = .001).

Conclusions: The mSST with delayed implant placement demonstrated superior maintenance of buccal
bone plate height and ridge width, along with significantly greater primary implant stability, compared to spontaneously
healed sockets. This approach is beneficial for maintaining ridge integrity when immediate implant placement is not
planned. Int J Oral Maxillofac Implants 2026;41:227–235. doi: 10.11607/jomi.11311

Alex Zusin, DDS1/Nathan E. Estrin, DDS, MS1/Yun Zhang, Student2/Georgios E. Romanos, DDS, PhD, Prof Dr Med Dentt1

Purpose: To evaluate the importance of clinical expertise on implant stability (IS) of 6-mm implants placed in vitro.

Materials and Methods: A total of 480 implants (Tapered Short Implants, BioHorizons) (6-mm length and diameters of 4.6mm and 5.8 mm) were used in this study. All implants were placed by three clinicians with different surgical experience levels: one master clinician (G.E.R.), one third-year resident with experience with nearly 100 implants (A.Z.), and one resident without implant surgical experience (N.E.E.). Each clinician placed 40 implants of each diameter (4.6 mm and 5.8 mm) in type 1 bone (dense) and 40 implants of each diameter in type 4 bone (soft; Sawbones), resulting in a total of 160 implants per clinician. Additionally, within each bone type, half of the implants (20 per diameter) were placed at bone level (crestal level), while the other half were placed 1 mm above the bone crest (supracrestal). The IS was evaluated using an Osstell device. Comparison of IS between all three clinicians for all implant groups was performed using oneway analysis of variance (ANOVA) and Bonferroni correction for multiple comparisons regarding the significance level, which was set at P < .05.

Results: Implants placed supracrestally showed differences between the experienced and inexperienced clinicians but not between the master clinician and third-year resident. A similar trend can be observed with implants placed at crestal levels. In type 1 bone, greater stability was achieved for the experienced clinicians when compared to the inexperienced one (P < .0001); however, in type 4 bone, the comparison of stability showed a P value < .0001 for all groups, with greater IS values for the master clinician over both residents.

Conclusions: Overall, both the master and moderately experienced surgeons presented increased stability on 6-mm implants compared to the inexperienced resident. Int J Oral Maxillofac Implants 2026;41:236–240. doi: 10.11607/jomi.11302

Seval Ceylan Şen, DDS, MSc1/Özlem Saraç Atagün, DDS, PhD1/Şeyma Çardakci Bahar, DDS, MSc1/Gülbahar Ustaoğlu, DDS, MSc1

Purpose: To analyze the use of immediate implants and loading techniques in dentistry through bibliometric methods, evaluate the publication and citation trends in this field, and identify the most influential studies.

Materials and Methods:
The Web of Science (WoS) Core Collection database was used as the bibliographic source, and a search strategy was applied to identify relevant research articles in the field. Bibliometric assessments were conducted using the Bibliometrix software. These analyses determined the collaboration networks of authors, keywords, and publications; research trends were identified using co-occurrence and co-citation analyses.

Results: The total number of publications peaked between 2010 and 2015. Citation numbers followed a similar trend, peaking in 2008 and becoming more prominent after 2020. Journals such as The International Journal of Oral & Maxillofacial Implants and Clinical Oral Implants Research are leading in the field of dental implantology, and authors like M. Esposito, U. Covani, and A. Piattelli are among the most productive in the field. The United States and Italy are among the leading countries for research in this area. Co-occurrence network
analyses, term co-occurrence map analysis, and co-citation analysis network have revealed the study and application trends, topics in implantology research, and the dynamics of this scientific field.

Conclusions: This bibliometric analysis demonstrated that studies on immediate implants and loading techniques represent a broad and continually evolving scientific field, offering potential collaborations and research directions for future researchers. Int J Oral Maxillofac Implants 2026;41:241–253. doi: 10.11607/jomi.11325

Filiz Yagcı, DDS, PhD1/Ravza Eraslan, DDS, PhD1/Haydar Albayrak, DDS, PhD1/Funda İpekten, PhD2

Purpose: To evaluate the accuracy, completeness, comprehensibility, and reliability of widely available artificial intelligence (AI) chatbots when addressing clinically significant queries pertaining to implant dentistry.

Materials and Methods: A total of 20 questions were devised based on a compiled list that were most frequently asked or encountered during patient consultations by three experienced prosthodontists. These questions were asked to ChatGPT-3.5, Gemini, and Copilot
AI chatbots on three separate occasions in 12-day intervals. A three-point Likert scale (0 = incorrect; 1 = incomplete or partially correct; 2 = correct) and a two-point scale (true and false) were employed by the authors to grade the accuracy of the responses independently. Completeness and comprehensibility were also evaluated using a three-point Likert scale (scored 1, 2, or 3, with lower scores indicating a worse result). In addition to the questions generated by the specialists, AI chatbots were asked to provide five frequently asked questions and responses regarding dental implant prostheses. A comparison of total scores obtained from the chatbots was made with one-way analysis of variance (ANOVA). Two-point scale data were analyzed via chi-square test. The reliability of the responses for each chatbot was analyzed by assessing the consistency of repeated responses via calculating Cronbach’s alpha (α) coefficients.

Results: When the total accuracy scores of the chatbots were analyzed out of a 40-point total score (ChatGPT-3.5 = 28.78 ± 4.06; Gemini = 30.89 ± 4.08; Copilot = 29.11 ± 3.22), one-way ANOVA revealed no statistically significant differences (P = .461). For the evaluation of two-point accuracy scale data, which were analyzed via chi-square test, no statistical differences were revealed among the chatbots (P = .336). Gemini showed a higher completeness level than ChatGPT-3.5 (P = .011). There was no statistically significant difference among AI chatbots in terms of comprehensibility. Copilot demonstrated the greatest overall consistency among the three chatbots, with a Cronbach’s α value of .863. This was followed by ChatGPT-3.5 with a Cronbach’s α value of .779 and Gemini with a Cronbach’s α value of .636.

Conclusions: The accuracy of all three chatbots were found to be similar. All three chatbots demonstrated an acceptable level of consistency. However, given the low accuracy rate of chatbots in answering questions, it is clear that they should not be relied upon as a decision-maker, and the clinician’s opinion must be given priority. Int J Oral Maxillofac Implants 2026;41:254–262. doi: 10.11607/jomi.11280

Ahmed Moustafa, BDS1/Mohamed Shawky, MSc2/Sara El Moshy, PhD3/Mohamed Mounir, PhD2,4/Yasmine Nassar, PhD2/Moataz Bahaa, PhD1

Purpose: To evaluate bone quality and quantity after 3D augmentation of vertically and horizontally atrophied maxillary ridges and compare the use of bone marrow aspirate concentrate (BMAC) and xenograft versus autograft and xenograft, both using prebent titanium (Ti) mesh over a virtually augmented model.

Materials and Methods: Ten fully edentulous patients with severe maxillary vertical and horizontal bone loss were recruited. Virtual horizontal and vertical bone augmentation was performed for the deficient ridge to produce virtually augmented models for prebent Ti meshes preoperatively. Each patient was rehabilitated with BMAC and xenograft on one side of their mouth (test side) and with autograft and xenograft on the other (control side). For the test side, the mesh was loaded with a mix of xenograft and BMAC from the anterior iliac crest. For the control side, the mesh was loaded with a 1:1 ratio of xenograft to autograft mix. The meshes on both sides were fixed in place using mini-screws.

Results: CBCT scans were performed 6 months postoperatively for all patients. The test side showed a mean vertical bone gain of 3.47 ± 0.87 mm, which was comparable to that of the control side (4.10 ± 0.67 mm). The test side also showed a mean horizontal bone gain of 3.476 ± 0.59 mm, which was higher than that of the control side (2.918 ± 0.80 mm). While the mean resorption rate in the test side (106.2 ± 108.6 mm) was lower than the mean value in the control side (193.3 ± 107.9 mm), the differences in bone gain were not statistically significant. However, a statistically significant higher bone area percentage (47.9%) as well as a higher percentage of mature bone (67.7%) were detected in the test side compared to the control side (28.5% and 26.5%, respectively).

Conclusions: 3D alveolar reconstruction using prebent Ti meshes loaded with xenograft mixed with BMAC could be a reliable and less complicated technique for vertically and horizontally atrophied maxillary ridges. Int J Oral Maxillofac Implants 2026;41:263–275. doi: 10.11607/jomi.11310

Hossein Salehivaziri, DDS1/Hojatollah Yousefimanesh, DDS, MS1/Leila Golpasand Hagh, DDS, MS1/Mahmoud Jahangirnezhad, DDS, MS1

Purpose: To investigate the distribution of stress in the bone around extra-short posterior mandibular implants to replace two molar teeth in six different treatment plans.

Materials and Methods: In this experimental study, preexisting CBCT data sets were imported into image-processing software (Mimics and 3-matic, Materialise) to create accurate 3D mandibular contours using finite element analysis (FEA). A total of 18 models for the reconstruction of the mandibular first and second molars were created based on the implant diameter, crown height, and splinted or nonsplinted form, with a 100-N load applied at a 30-degree angle. Two extra-short implants with a length of 4 mm and a diameter of 4.1 mm and/or 4.8 mm were used; the crown heights were 15 mm, 12.5 mm, and 10 mm, depending on the model.

Results: The study of stresses in cortical bone, trabecular bone, implants, and crowns revealed that the highest stress levels (ie, 118.27 MPa in cortical bone) were associated with the treatment plan involving two implants with a diameter of 4.1 mm without a splint and
a crown height of 15 mm. Conversely, the lowest amount of stress (ie, 29.12 MPa in cortical bone) was observed in the treatment plan with two implants with a diameter of 4.8 mm without a splint and a crown height of 10 mm. Crown height influenced stress the most (≤ 237.6% increase), followed by diameter (≤ 63.7% reduction, weakened at higher crowns), while the type of splinting effects varied (ie, +122.7% crown stress increase in specific cases); cortical bone stayed below a 130 MPa safe zone, but trabecular bone often exceeded 10 MPa.

Conclusions: Increasing the height of the crown in nonsplinted implants leads to an increase in stress distribution in all cases of the treatment plan outlined in this study, with statistical analysis suggesting trabecular bone risk and a need for fatigue studies. Int J Oral Maxillofac Implants 2026;41:276–286. doi: 10.11607/jomi.11298

Liying Lin, MSC1/Dongyan Zhang, PhD2

Purpose: To investigate dental implant bone grafting in the literature to obtain a comprehensive understanding of the current research landscape and emerging trends in this topic via bibliometric analysis, thereby informing future research directions to ensure the long-term stability of implants.

Materials and Methods: Using the Web of Science database, we conducted a comprehensive search for articles pertaining to dental implant bone grafting published between January 1, 2014, and November 20, 2024. Our analysis encompassed several bibliometric parameters, including the number of publications, publication year, journal, impact factor, title, author, institution, keywords, and citation count. We employed VOS viewer to perform keyword co-occurrence network analysis and co-citation network analysis, and CiteSpace was used for national collaboration analysis and coupled clustering. Additionally, we leveraged online platforms for further
visualizations.

Results: A comprehensive search yielded 384 articles published across 143 journals, authored by 2,066 individuals affiliated with 714 institutions spanning 52 countries, and encompassing 1,886 distinct keywords. The journals Clinical Oral Implants Research and The International Journal of Oral & Maxillofacial Implants exhibited the highest publication volumes. Seoul National University emerged as the most prolific institution in this domain. China was identified as the leading country in terms of publication output, while the United States demonstrated the highest level of international collaboration. The term “osseointegration” was the most frequently occurring keyword.

Conclusions: This study quantitatively analyzes the literature on dental implant bone grafting from the past decade, highlighting a shift from focusing solely on implants to actively promoting bone regeneration using biologic materials and technology. Future developments emphasize the transition from macroscopic to molecular biology, along with drug-assisted treatments, digitalization, and personalization. Int J Oral Maxillofac Implants 2026;41:287–297. doi: 10.11607/jomi.11283