Root surface biomodification in periodontal therapy: Biological rationale and clinical applications.

Regenerative periodontal therapy aims to form new cementum, periodontal ligament, and alveolar bone, all sealed by gingival tissue. The root surface acts as the wound margin during this regeneration process. Root surface biomodification (root conditioning/root decontamination), therefore, seems instrumental in promoting surface decontamination and enhancing tissue attachment by removing the smear layer, exposing collagen fibrils, and facilitating blood clot formation and stabilization. This review attempted to provide an all-encompassing, evidence-based assessment of the role of root surface biomodification in regenerative periodontal therapy, particularly in intrabony defects, furcation defects, and root coverage procedures. The reviewed evidence suggested that root conditioning agents, whether used independently or in conjunction with bone graft materials, biological agents, membranes, or connective tissue grafts, do not offer any clinical advantage regarding clinical attachment gain. Thus, integrating chemical methods with the mechanical root instrumentation process does not necessarily contribute to superior clinical outcomes.

Impact of smoking on cost-effectiveness of 10-48 years of periodontal care.

The study aims were (1) to explore whether "periodontal treatment" consisting of surgical therapy (flap, resective, or regenerative) or scaling and root planing treatment with long-term periodontal maintenance treatment, is cost-effective in terms of preventing periodontitis-attributable tooth extraction and replacement by implant-supported crowns ("extraction/replacement"); (2) to assess the effect of cigarette smoking on this cost-effectiveness. Data for this observational retrospective study were collected from dental charts of patients who had received periodontal therapy and at least annual follow-up visits for >10 years were analyzed by linear regression generalized estimating equations and generalized linear models. Among 399 adults (199 males, 200 females), those with the least mean annual treatment cost experienced the greatest mean annual costs for extraction/replacement, indicating general cost-effectiveness. Cigarette smoking adversely impacted this cost-effectiveness, with current heavy smokers experiencing no cost-effectiveness. Former smokers with Grade C periodontitis benefitted most, whereas smoking did not influence cost-effectiveness for Grade B periodontitis. Assessed by mean annual costs of "extraction/replacement," periodontal treatment was cost-effective, which decreased in a dose-response manner by former and current smoking intensity. Cigarette smoking should be factored into treatment planning and cost-effective analyses of periodontal treatment. Smoking cessation should be encouraged.

Performance of three artificial intelligence (AI)-based large language models in standardized testing; implications for AI-assisted dental education.

INTRODUCTION: The emerging rise in novel computer technologies and automated data analytics has the potential to change the course of dental education. In line with our long-term goal of harnessing the power of AI to augment didactic teaching, the objective of this study was to quantify and compare the accuracy of responses provided by ChatGPT (GPT-4 and GPT-3.5) and Google Gemini, the three primary large language models (LLMs), to human graduate students (control group) to the annual in-service examination questions posed by the American Academy of Periodontology (AAP). METHODS: Under a comparative cross-sectional study design, a corpus of 1312 questions from the annual in-service examination of AAP administered between 2020 and 2023 were presented to the LLMs. Their responses were analyzed using chi-square tests, and the performance was juxtaposed to the scores of periodontal residents from corresponding years, as the human control group. Additionally, two sub-analyses were performed: one on the performance of the LLMs on each section of the exam; and in answering the most difficult questions. RESULTS: ChatGPT-4 (total average: 79.57%) outperformed all human control groups as well as GPT-3.5 and Google Gemini in all exam years (p < .001). This chatbot showed an accuracy range between 78.80% and 80.98% across the various exam years. Gemini consistently recorded superior performance with scores of 70.65% (p = .01), 73.29% (p = .02), 75.73% (p < .01), and 72.18% (p = .0008) for the exams from 2020 to 2023 compared to ChatGPT-3.5, which achieved 62.5%, 68.24%, 69.83%, and 59.27% respectively. Google Gemini (72.86%) surpassed the average scores achieved by first- (63.48% ± 31.67) and second-year residents (66.25% ± 31.61) when all exam years combined. However, it could not surpass that of third-year residents (69.06% ± 30.45). CONCLUSIONS: Within the confines of this analysis, ChatGPT-4 exhibited a robust capability in answering AAP in-service exam questions in terms of accuracy and reliability while Gemini and ChatGPT-3.5 showed a weaker performance. These findings underscore the potential of deploying LLMs as an educational tool in periodontics and oral implantology domains. However, the current limitations of these models such as inability to effectively process image-based inquiries, the propensity for generating inconsistent responses to the same prompts, and achieving high (80% by GPT-4) but not absolute accuracy rates should be considered. An objective comparison of their capability versus their capacity is required to further develop this field of study.

Association between asthma and periodontitis: A case-control analysis of risk factors, related medications, and allergic responses.

AIMS: This study aimed to investigate the association between asthma, related allergies and medication use, and the presence and severity of periodontitis among individuals at the University of Michigan School of Dentistry. METHODS: Employing a case-control design, the study analyzed data from 892 patients, half with asthma and half without asthma. Data collection included demographics, asthma history, medication use, allergies, and periodontal examination outcomes, including probing pocket depth (PPD), mobility, furcation involvement, and radiographic bone loss (RBL). Logistic regression models assessed the relationship between asthma and periodontitis, adjusting for confounders. RESULTS: Asthmatic patients exhibited significantly lower odds of periodontitis (OR = 0.10, p < .001) and were less likely to present with advanced stages (OR = 0.23, p < .001) and grades of the disease (OR = 0.31, p < .001) compared to non-asthmatic patients. The study also found a higher proportion of females in the asthmatic group (67% vs. 51.8%, p < .001). Smoking was identified as a significant factor associated with periodontitis in patients with asthma, with former smokers at more than double the odds (OR = 2.28, p = .035) and current smokers at a slightly lower yet significant odds (OR = 1.87, p = .050). Additionally, asthmatic patients on adrenergic inhalers had an increased likelihood of developing periodontitis (OR = 1.76, p = .045). Allergies to codeine and latex were associated with higher odds of periodontitis, with ORs of 3.41 and 6.09, respectively. CONCLUSIONS: Asthma was found to be associated with lower odds of periodontitis. However, this association appears to be modified by smoking habits and the use of certain asthma medications, which are related to an increased likelihood of periodontitis among asthmatic patients.

Periodontitis stage and grade modifies the benefit of regular supportive periodontal care in terms of need for retreatment and mean cumulative cost.

AIM: This study aimed to characterize the periodontal breakdown during supportive periodontal care (SPC) and to quantify the corresponding cost-effectiveness of periodontal therapy. MATERIALS AND METHODS: Data were obtained from charts of patients who received active periodontal therapy (APT) with a minimum follow-up of ≥10 years. Analysis was done to identify factors associated with the incidence of additional sub-gingival instrumentation (SGI) and/or surgery (SUR) during SPC and mean cumulative cost of recurrence was calculated. All relevant data were collected. RESULTS: In all, 442 patients were included. Over the follow-up period, 62% of Stage I and II patients and 72% of Stage III and IV patients required further treatment following the APT; 56.5% of SGI patients and 78.6% of SUR patients received a second intervention. SUR patients received more SUR during the follow-up period (p = .035). Stage III and IV patients received more SUR during SPC than Stage I and II patients (p = .001). Grade C patients received more SUR during the follow-up period (p < .05). During the 5-year period preceding retreatment, the mean SPC visits were lower for patients who did not require retreatment (p < .001). Risk factors such as regularity of maintenance, smoking and diabetes were related to a higher chance of receiving SUR during the follow-up period (p < .05). The mean cumulative costs indicated less recurrence cost for compliers in Stage III and IV or Grade B and C but not for those in Stage I and II or Grade A. CONCLUSIONS: The risk of relapse in the maintenance population may be correlated with higher stage and grade, patient compliance, modifiable risk factors and the nature of the treatment provided during APT. The total cost of treatment of recurrences was lower for compliers in Stage III/IV and Grade B/C compared with erratic compliers with the same severity and risk.

Accuracy of edentulous full-arch implant impression: An in vitro comparison between conventional impression, intraoral scan with and without splinting, and photogrammetry.

OBJECTIVES: The purpose of this in vitro study was to compare the trueness and precision of complete arch implant impressions using conventional impression, intraoral scanning with and without splinting, and stereophotogrammetry. MATERIALS AND METHODS: An edentulous model with six implants was used in this study. Four implant impression techniques were compared: the conventional impression (CI), intraoral scanning (IOS) without splinting, intraoral scanning with splinting (MIOS), and stereophotogrammetry (SPG). An industrial blue light scanner was used to generate the baseline scan from the model. The CI was captured with a laboratory scanner. The reference best-fit method was then applied in the computer-aided design (CAD) software to compute the three-dimensional, angular, and linear discrepancies among the four impression techniques. The root mean square (RMS) 3D discrepancies in trueness and precision between the four impression groups were analyzed with a Kruskal-Wallis test. Trueness and precision between single analogs were assessed using generalized estimating equations. RESULTS: Significant differences in the overall trueness (p = .017) and precision (p < .001) were observed across four impression groups. The SPG group exhibited significantly smaller RMS 3D deviations than the CI, IOS, and MIOS groups (p < .05), with no significant difference detected among the latter three groups (p > .05). CONCLUSIONS: Stereophotogrammetry showed superior trueness and precision, meeting misfit thresholds for implant-supported complete arch prostheses. Intraoral scanning, while accurate like conventional impressions, exhibited cross-arch angular and linear deviations. Adding a splint to the scan body did not improve intraoral scanning accuracy.

Accuracy of open-sleeved vs. closed-sleeved static computer-assisted implant systems in immediate maxillary molar implant placement: An in vitro study.

OBJECTIVES: The objective of this study is (1) to compare the accuracy of an open-sleeved static computer-assisted implant system (sCAIS) with a closed-sleeve sCAIS and free-hand approach in immediate implant placement (IIP) of maxillary molar sites and (2) to investigate the influence of socket morphology on these approaches. MATERIALS AND METHODS: Ninety partially edentulous duplicated maxillary models simulating three different molar sockets (type A, B, and C based on Smith and Tarnow's classification) were investigated. Three modalities, including sCAIS with open-sleeves, sCAIS with closed-sleeves, and free-hand approach, were applied separately to 30 models with 120 sockets. A customized Python script automatically measured the deviations between the virtual and actual implant positions for all 360 implants. RESULTS: The 3D deviations of sCAIS were significantly influenced by the socket and sleeve types. Both guided groups exhibited significantly less deviation than the free-hand approach. Type A and C sockets resulted in better implant positions than type B socket sites. In type B sockets, the open-sleeve group achieved significantly less deviation compared to the closed-sleeve group, with respect to apical global (1.34 ± 0.53 vs. 1.84 ± 0.59 mm), coronal horizontal (0.68 ± 0.36 vs. 0.93 ± 0.34 mm), apical horizontal (1.21 ± 0.59 vs. 1.74 ± 0.63 mm), and angular (3.30 ± 1.41 vs. 4.41 ± 1.96°) deviations. CONCLUSIONS: Guided implant surgery significantly reduces deviations during molar IIP compared to free-hand procedures. Furthermore, the use of open-sleeve sCAIS appears to be more effective in minimizing deviations in type B sockets when compared with the closed-sleeve guided system.

Five decades of research on immediate implant therapy: A modern bibliometric network analysis via Altmetric and level of evidence mapping.

AIM: To conduct a bibliometric network analysis to explore the research landscape of immediate implant placement (IIP) and provide insights into its trends and contributors. MATERIALS AND METHODS: The Scopus database was utilized as the bibliographic source, and a search strategy was implemented to identify relevant research articles. Various bibliometric parameters were extracted, including publication year, journal, authors, citations, and funding. The analysis involved examining authorship patterns, international collaborations, level of evidence, Altmetric data, and funding analysis. RESULTS: We identified a steady annual growth rate of 6.49% in IIP research. The top three countries contributing to research output were the USA, Italy, and China. Prolific authors were identified based on publication and citation metrics. International collaborations among different countries were observed. The level of evidence analysis revealed that over 30% of the articles fell into higher levels of evidence (levels 1 and 2). Altmetric data analysis indicated no significant correlations between citation counts and Altmetric Attention Score (AAS), and conversely a significant association with Mendeley readers count. Funding and open access did not significantly impact the bibliometric indices of the papers. CONCLUSIONS: The focus of research on IIP has been evolving as indicated by an exponential growth rate in this study. Only approximately 16% of the articles fit into level 1 evidence, therefore, emphasizing on higher quality level research study shortage in this field. Modern indices can be used as new bibliometric indicators as they also cover social media and online attention scores.

Factors associated with furcation involvement and fixed prostheses: A cross-sectional study.

OBJECTIVE: The study aims to explore the relationship between horizontal and vertical furcation involvement (FI) in teeth with or without a single unit fixed prosthesis (FP). MATERIALS AND METHODS: Adult subjects presenting to the periodontics department requiring cone beam computed tomography (CBCT) analysis were recruited for this study. 79 patients, with a total of 200 teeth, were split into two groups based on the presence or absence of FP within the same patient. Our analysis considered patient-level factors like smoking, diabetes, and periodontal severity and tooth-level factors including root trunk length (RTL), probing depth (PD), periodontal supracrestal tissue height (STH), supracrestal tissue attachment (STH-PD), interproximal bone distance (IPBD) to the cementoenamel junction (CEJ) (control) or crown margin (Test), and the distance from the furcation to the CEJ (control) or crown margin (Test). Subsequently, we developed a predictive model for FI. RESULTS: The presence of a prosthesis had a significant association with FI, with an odds ratio (OR) of 12.8 (p < 0.001). Other factors significantly correlated with FI were periodontitis (OR = 10.9; p = 0.006), buccal furcation site (OR = 5.70; p < 0.001), and PD (OR = 1.90; p = 0.027). FP placement increased IPBD by 1.08 mm (p < 0.001). The predictive model built for FI demonstrated a sensitivity of 92.9% and a specificity of 66.7%. CONCLUSIONS: Fixed prosthesis significantly influenced FI only in periodontitis patients. Factors such as periodontitis Stage, probing depth, and buccal site contribute to FI. The high sensitivity of the predictive model highlights the importance of considering these correlations during treatment planning. CLINICAL RELEVANCE: Comprehending FI factors is vital for devising customised treatment plans to halt disease progression and enhance outcomes of periodontal regenerative therapies.

Hyperbaric oxygen therapy as an adjunct treatment of periodontitis, MRONJ, and ONJ: a systematic literature review.

OBJECTIVE: To review the available prospective literature on hyperbaric oxygen (HBO) therapy for periodontal conditions. MATERIALS AND METHODS: A comprehensive electronic and manual search was performed to identify clinical studies on adult patients who underwent hyperbaric oxygen therapy for periodontal treatments. A systematic literature search was conducted in PubMed, Cochrane, and Dentistry Oral Sciences Source databases. RESULTS: Fourteen articles were included in the final literature review, of which five were RCTs and 11 were prospective clinical studies. Four studies discussed HBO as an adjunct to nonsurgical treatment of periodontitis, eight reported on HBO and osteoradionecrosis, and one examined HBO in bisphosphonate-related necrosis of the jaws. CONCLUSIONS: HBO has shown superior efficacy compared to antibiotics as a prophylactic measure in preventing osteoradionecrosis (ORN) in patients with a history of high mandibular irradiation. Clinicians should consider referring such patients for HBO therapy before and after tooth extractions. However, for the surgical excision of existing ORN lesions, HBO therapy does not yield significant benefits but does not negatively impact outcomes either. Regarding the treatment of periodontitis patients, the variability among studies prevents definitive conclusions. HBO therapy as an adjunct to SRP in periodontitis treatment produces mixed results. CLINICAL RELEVANCE: This study's clinical relevance lies in its exploration of the potential benefits of HBO for periodontal conditions. Also, it provides clinicians with insights into when and how to integrate HBO therapy into their treatment approaches, particularly for patients with a history of irradiation and those undergoing complex dental procedures.

Residual vertical defects: risk of disease progression, retreatment rates, and cost: a retrospective analysis.

OBJECTIVES: This study aimed to explore the relationship between Radiographic Residual Vertical Defects (RVDs) and the progression of periodontitis in patients undergoing periodontal maintenance therapy (PMT). MATERIALS AND METHODS: Teeth with RVDs were compared to the same contralateral teeth in the same patient. The study investigated the effect of smoking, diabetes, compliance, disease Stage, and Grade, baseline probing depth (PD), periodontal risk score (PRS), baseline pocket closure (PC) (≤ 4 mm), and tooth mobility on disease progression. We calculated the need for retreatment during PMT and its associated cost. Generalized estimation equations and linear and multilevel logistic regression analyses were employed for data analysis. RESULTS: Each group had 139 teeth, accounting for 80 patients. Although the group with RVDs had similar PD reduction compared to the control teeth, the prevalence of PC at the last follow-up was reduced to half in the RVDs group (odds ratio OR = 0.5; p-value = 0.028), regardless of PC status at the baseline. RVDs were also significant predictors of tooth loss due to periodontitis (TLP), with an OR of 2.28 (p = 0.043). Patients with diabetes, Stage IV, higher mobility, and higher PRS scores had a higher risk of tooth loss due to periodontitis (OR = 4.71, 3.84, 3.64, and 5.97, respectively (P < 0.01). Incidences of sites requiring retreatment were similar in both groups, but the cost of treatment was 30% higher for teeth with RVDs. Grade C had the most significant influence on receiving retreatments (OR = 18.8, p = 0.005). CONCLUSION: Teeth with RVDs represent a risk indicator for tooth loss compared to identical contralateral teeth with similar PD in the same patient. Teeth with RVD had more risk of pocket opening during follow-up. CLINICAL RELEVANCE: While teeth with RVDs can be maintained long-term, they have twice the risk of pocket opening and tooth loss due to periodontitis during follow-up. Patients with systemic and local risk factors need to be monitored closely as they are at the highest risk of losing teeth with RVDs. The increased cost of retreatment for teeth with RVDs also has implications in terms of retention versus extraction and replacement.

Recommendations for successful virtual patient-assisted esthetic implant rehabilitation: A guide for optimal function and clinical efficiency.

OBJECTIVE: Complete arch implant rehabilitation necessitates meticulous treatment planning and high-level collaboration between surgical and prosthetic dental teams. Emerging virtual technologies hold considerable promise in streamlining this process. The aim of this article is to extend recommendations to clinicians venturing into the virtual patient-assisted esthetic implant rehabilitation workflow. OVERVIEW: This article summarizes recommendations for virtual patient-assisted esthetic implant rehabilitation in the following five aspects: three-dimensional data handling and superimposition, occlusion and virtual articulator integration in creating virtual patients, streamlined face- and prosthetic-driven surgical planning, reuse of presurgical data ("Copy & Paste"), and final impression for passive fitting of final restoration. To illustrate these principles, a case with complete-mouth implant rehabilitation completed within six visits using this virtual patient workflow is presented. CONCLUSION: The virtual patient workflow serves as an invaluable tool to perform treatment planning, enhance efficiency, and ensure predictable outcomes in esthetic complete arch implant rehabilitation. CLINICAL SIGNIFICANCE: Virtual workflows are increasingly prevalent in esthetic implant rehabilitation. Nevertheless, these workflows necessitate a distinct set of knowledge and tools divergent from conventional dentistry practices. This article offers guidelines and recommendations for dental clinicians who are new to this field.

Complications and treatment errors in periodontal and implant therapy.

The assortment of periodontal and implant-related treatments has been continuously improved over the last 50 years. Once the decision-making process has been established and the treatment procedure applied, the partial or complete resolution of the problem (eg, periodontal probing depth reduction, clinical attachment level gain, gingival recession reduction, dental hypersensitivity decrease) and a diagnosis change with no or minimal occurrence of adverse events (ie, complications, harms, technical errors, or adverse/side effects) can be expected. The clear identification of the potential types of adverse effects, complications, or even errors is important for contemporary decision-making processes, as they may be related to different local, systemic, and technical aspects. This chapter focused on four core components: (a) providing periodontal definitions for errors, complications, harms, and side effects; (b) defining the types of risk and the clinical impact of adverse effects, errors, and complications in periodontal and peri-implant therapies; (c) evaluating the influence of accidental errors versus the lack of a proper treatment planning; and (d) reporting on the importance of establishing the "net benefit ratio" between the clinical improvements promoted by the therapy and the occurrence of potential adverse events.

Emerging factors affecting peri-implant bone metabolism.

Implant dentistry has evolved to the point that standard implant osseointegration is predictable. This is attributed in part to the advancements in material sciences that have led toward improvements in implant surface technology and characteristics. Nonetheless, there remain several cases where implant therapy fails (specifically at early time points), most commonly attributed to factors affecting bone metabolism. Among these patients, smokers are known to have impaired bone metabolism and thus be subject to higher risks of early implant failure and/or late complications related to the stability of the peri-implant bone and mucosal tissues. Notably, however, emerging data have unveiled other critical factors affecting osseointegration, namely, those related to the metabolism of bone tissues. The aim of this review is to shed light on the effects of implant-related factors, like implant surface or titanium particle release; surgical-related factors, like osseodensification or implanted biomaterials; various drugs, like selective serotonin reuptake inhibitors, proton pump inhibitors, anti-hypertensives, nonsteroidal anti-inflammatory medication, and statins, and host-related factors, like smoking, diet, and metabolic syndrome on bone metabolism, and aseptic peri-implant bone loss. Despite the infectious nature of peri-implant biological complications, these factors must be surveyed for the effective prevention and management of peri-implantitis.

Simultaneous or staged lateral ridge augmentation: A clinical guideline on the decision-making process.

Lateral ridge augmentation is a standard surgical procedure that can be performed prior to (staged) or simultaneously with implant placement. The decision between a simultaneous or staged approach involves considering multiple variables. This paper proposed a decision-making process that serves as a guideline for choosing the best treatment choice based on the available evidence and the author's clinical experience.

Alveolar ridge preservation: Complications and cost-effectiveness.

Alveolar ridge preservation is routinely indicated in clinical practice with the purpose of attenuating postextraction ridge atrophy. Over the past two decades numerous clinical studies and reviews on this topic have populated the literature. In recent years the focus has primarily been on analyzing efficacy outcomes pertaining to postextraction dimensional changes, whereas other relevant facets of alveolar ridge preservation therapy have remained unexplored. With this premise, we carried out a comprehensive evidence-based assessment of the complications associated with different modalities of alveolar ridge preservation and modeled the cost-effectiveness of different therapeutic modalities as a function of changes in ridge width and height. We conclude that, among allogeneic and xenogeneic bone graft materials, increased expenditure does not translate into increased effectiveness of alveolar ridge preservation therapy. On the other hand, a significant association between expenditure on a barrier membrane and reduced horizontal and vertical ridge resorption was observed, though only to a certain degree, beyond which the return on investment was significantly diminished.

Wound healing dynamics, morbidity, and complications of palatal soft-tissue harvesting.

Palatal-tissue harvesting is a routinely performed procedure in periodontal and peri-implant plastic surgery. Over the years, several surgical approaches have been attempted with the aim of obtaining autogenous soft-tissue grafts while minimizing patient morbidity, which is considered the most common drawback of palatal harvesting. At the same time, treatment errors during the procedure may increase not only postoperative discomfort or pain but also the risk of developing other complications, such as injury to the greater palatine artery, prolonged bleeding, wound/flap sloughing, necrosis, infection, and inadequate graft size or quality. This chapter described treatment errors and complications of palatal harvesting techniques, together with approaches for reducing patient morbidity and accelerating donor site wound healing. The role of biologic agents, photobiomodulation therapy, local and systemic factors, and genes implicated in palatal wound healing are also discussed.

How to avoid intraoperative and postoperative complications in maxillary sinus elevation.

Maxillary sinus floor elevation, via the lateral approach, is one of the most predictable bone augmentation procedures performed in implant dentistry. but both intra- and postoperative complications can occur, and some of them are severe. Our aim is as follows: To review the pertinent literature on the topic, especially assessing the risk factors related to complications. To give clinical recommendations to minimize intra- and postoperative complications with the ultimate scope of improving the standard of clinical care and patient safety.

Doppler ultrasonographic evaluation of tissue revascularization following connective tissue graft at implant sites.

AIM: To assess the Doppler ultrasonographic tissue perfusion at dental implant sites augmented with connective tissue graft (CTG) using coronally advanced flap (CAF) or tunnel technique (TUN). MATERIALS AND METHODS: Twenty-eight patients presenting with isolated healthy peri-implant soft-tissue dehiscence (PSTD) were included in this randomized clinical trial. PSTDs were treated with either CAF + CTG or TUN + CTG. Ultrasound scans were taken at baseline, 1 week, 1 month, 6 months and 12 months. Tissue perfusion at the mid-facial, mesial and distal aspects of the implant sites was assessed by colour Doppler velocity (CDV) and power Doppler imaging (PDI). Early vascularization of the graft and the flap at 1 week and at 1 month were evaluated via dynamic tissue perfusion measurements (DTPMs), including flow intensity (FI), mean perfusion relief intensity (pRI) and mean perfused area (pA). RESULTS: Regression analysis did not reveal significant differences in terms of mid-facial CDV and PDI changes between CAF and TUN over 12 months (p > .05), while significant differences between the two groups were observed at the interproximal areas (p < .001 for both CDV and PDI changes). Higher early DTPMs were observed at the TUN-treated sites in terms of mean FI of the graft (p = .027) and mean FI (p = .024) and pRI of the flap (p = .031) compared with CAF-treated sites at 1 week. Assessment of the FI direction showed that CTG perfusion at 1 week and at 1 month mainly occurred from the flap towards the implant/bone. Early tissue perfusion outcomes were found to be associated with the 12-month mean PSTD coverage and mucosal thickness gain. CONCLUSIONS: Doppler ultrasonography shows tissue perfusion changes occurring at implant sites augmented with CTG. The main differences in tissue perfusion between CAF and TUN were observed at the interproximal sites, with early perfusion associated with clinical and volumetric outcomes at 12 months.

Development and international validation of logistic regression and machine-learning models for the prediction of 10-year molar loss.

AIM: To develop and validate models based on logistic regression and artificial intelligence for prognostic prediction of molar survival in periodontally affected patients. MATERIALS AND METHODS: Clinical and radiographic data from four different centres across four continents (two in Europe, one in the United States, and one in China) including 515 patients and 3157 molars were collected and used to train and test different types of machine-learning algorithms for their prognostic ability of molar loss over 10 years. The following models were trained: logistic regression, support vector machine, K-nearest neighbours, decision tree, random forest, artificial neural network, gradient boosting, and naive Bayes. In addition, different models were aggregated by means of the ensembled stacking method. The primary outcome of the study was related to the prediction of overall molar loss (MLO) in patients after active periodontal treatment. RESULTS: The general performance in the external validation settings (aggregating three cohorts) revealed that the ensembled model, which combined neural network and logistic regression, showed the best performance among the different models for the prediction of MLO with an area under the curve (AUC) = 0.726. The neural network model showed the best AUC of 0.724 for the prediction of periodontitis-related molar loss. In addition, the ensembled model showed the best calibration performance. CONCLUSIONS: Through a multi-centre collaboration, both prognostic models for the prediction of molar loss were developed and externally validated. The ensembled model showed the best performance in terms of both discrimination and validation, and it is made freely available to clinicians for widespread use in clinical practice.