Accuracy and safety of a haptic operated and machine vision controlled collaborative robot for dental implant placement: A translational study.

OBJECTIVES: Multiple generations of medical robots have revolutionized surgery. Their application to dental implants is still in its infancy. Co-operating robots (cobots) have great potential to improve the accuracy of implant placement, overcoming the limitations of static and dynamic navigation. This study reports the accuracy of robot-assisted dental implant placement in a preclinical model and further applies the robotic system in a clinical case series. MATERIALS AND METHODS: In model analyses, the use of a lock-on structure at robot arm-handpiece was tested in resin arch models. In a clinical case series, patients with single missing teeth or edentulous arch were included. Robot-assisted implant placement was performed. Surgery time was recorded. Implant platform deviation, apex deviation, and angular deviation were measured. Factors influencing implant accuracy were analyzed. RESULTS: The in vitro results showed that with a lock-on structure, the mean (SD) of platform deviation, apex deviation, and angular deviation were 0.37 (0.14) mm, 0.44 (0.17) mm, and 0.75 (0.29)°, respectively. Twenty-one patients (28 implants) were included in the clinical case series, 2 with arches and 19 with single missing teeth. The median surgery time for single missing teeth was 23 (IQ range 20-25) min. The surgery time for the two edentulous arches was 47 and 70 min. The mean (SD) of platform deviation, apex deviation, and angular deviation was 0.54 (0.17) mm, 0.54 (0.11) mm, and 0.79 (0.22)° for single missing teeth and for 0.53 (0.17) mm, 0.58 (0.17) mm, and 0.77 (0.26)° for an edentulous arch. Implants placed in the mandible had significantly larger apex deviation than those in the maxilla. CONCLUSION: Cobot-assisted dental implant placement showed excellent positional accuracy and safety in both the in vitro study and the clinical case series. More technological development and clinical research are needed to support the introduction of robotic surgery in oral implantology. Trial registered in ChiCTR2100050885.

Reliability assessment of the 2018 classification case definitions of peri-implant health, peri-implant mucositis, and peri-implantitis.

BACKGROUND: The purpose of this study was to evaluate the reliability and accuracy in the assignment of the case definitions of peri-implant health and diseases according to the 2018 Classification of Periodontal and Peri-implant Diseases and Conditions. METHODS: Ten undergraduate students, 10 general dentists, and 10 experts in implant dentistry participated in this study. All examiners were provided with clinical and radiographic documentation of 25 dental implants. Eleven out the 25 cases were also accompanied by baseline readings. Examiners were asked to define all cases using the 2018 classification case definitions. Reliability among examiners was evaluated using the Fleiss kappa statistic. Accuracy was estimated using percentage of complete agreement and quadratic weighted kappa for pairwise comparisons between each rater and a gold standard diagnosis. RESULTS: The Fleiss kappa was 0.50 (95% CI: 0.48 to 0.51) and the mean quadratic weighted kappa value was 0.544. Complete agreement with the gold standard diagnosis was achieved in 59.8% of the cases. Expertise in implantology affected accuracy positively (p < 0.001) while the absence of baseline readings affected it negatively (p < 0.001). CONCLUSION: Both reliability and accuracy in assigning case definitions to dental implants according to the 2018 classification were mostly moderate. Some difficulties arose in the presence of specific challenging scenarios.

Modified minimally invasive surgical technique in human intrabony defects with or without regenerative materials-10-year follow-up of a randomized clinical trial: Tooth retention, periodontitis recurrence, and costs.

AIM: The modified minimally invasive surgical technique (M-MIST) optimizes wound stability in the treatment of intrabony defects. Short-term observations show similar results as with flap alone or adjunctive regenerative materials. This study aims to compare the stability of the long-term outcomes, complication-free survival, and costs of the three treatment options. MATERIALS AND METHODS: Forty-five intrabony defects in 45 patients were randomized to M-MIST alone (N = 15), combined with enamel matrix derivative (M-MIST + EMD, N = 15), or EMD plus bone-mineral-derived xenograph (M-MIST + EMD + BMDX, N = 15). Supportive periodontal care (SPC) and necessary re-treatment were provided for 10 years. RESULTS: Three subjects were lost to follow-up. Clinical attachment level differences between 1 and 10 years were -0.1 ± 0.7 mm for M-MIST, -0.1 ± 0.8 mm for M-MIST + EMD, and -0.3 ± 0.6 mm for M-MIST + EMD + BMDX (p > .05 for within- and between-group differences). Four episodes of recurrence occurred in the M-MIST group, four in the M-MIST + EMD group, and five in the M-MIST + EMD + BMDX group. No significant differences in complication-free survival were observed between the three groups (p = .47). Complication-free survival was 7.46 years (95% confidence interval: 7.05-7.87) for the whole population. The M-MIST + EMD + BMDX group lost one treated tooth. Data indicated no significant inter-group difference of the total cost of recurrence over 10 years. When the baseline cost of treatment was considered, the total cost was lower for M-MIST alone. CONCLUSIONS: Teeth with deep pockets associated with intrabony defects can be successfully maintained over the long term with either M-MIST alone or by adding a regenerative material in the context of a careful SPC programme. M-MIST alone provided similar short- and long-term benefits as regeneration, at a lower cost. These findings need to be confirmed in larger, independent studies.

Assessment of masticatory function in the differential diagnosis of Stage IV periodontitis: A pilot diagnostic accuracy study.

BACKGROUND: After diagnosis of periodontitis is made, detection of Stage IV cases is critical for appropriate management that may call for interdisciplinary care. This study aims to identify and assess the accuracy of a simple screening approach for practice and surveillance of Stage IV periodontitis. METHODS: Masticatory function assessments by both validated self-reported masticatory dysfunction questionnaire and dual-color chewing gum mixing ability test (index test) were conducted in 214 consecutive patients, followed by a full-mouth periodontal examination. Periodontal diagnosis was based on the 2017 World Workshop classification of periodontal diseases (reference standard). Multivariate logistic regression and area under the receiver operating characteristic curve (AUROC) analyses were performed. RESULTS: Overall, the individual patient-reported masticatory dysfunction questions showed low to moderate accuracy for predicting Stage IV periodontitis. The objective measures of masticatory function by calculating the variance of hue from the chewing gum test performed better with an AUROC of 0.840. A diagnostic approach based on age, self-report of altered food type intake, and chewing gum test results exhibited excellent performance for predicting Stage IV periodontitis (sensitivity: 89.7%; specificity:76.3%; AUROC:0.912). CONCLUSIONS: Once the presence of periodontitis has been established, a simple diagnostic approach that does not require specialized workforce, complex, or lengthy assessment allows identification of patients with Stage IV periodontitis. This is important as these patients require specific case work up and interdisciplinary care pathways. Additional studies are required to validate the findings in multiple populations.

Clinical, radiographic and economic evaluation of short-6-mm implants and longer implants combined with osteotome sinus floor elevation in moderately atrophic maxillae: A 3-year randomized clinical trial.

AIM: To compare the 3-year clinical, radiographic and economic outcomes of short-6-mm implants and longer implants combined with osteotome sinus floor elevation (OSFE) in the posterior maxilla. MATERIAL AND METHODS: This study enrolled 225 patients (225 implants with diameter of 4.1 mm and 4.8 mm) with a posterior maxillary residual bone height (RBH) of 6-8 mm. Patients were randomly divided into three groups: Group 1 (6 mm implants alone), Group 2 (8 mm implants + OSFE) and Group 3 (10 mm implants + OSFE). The following outcomes were recorded at 1 and 3-year examinations: implant survival, probing pocket depth (PPD), bleeding on probing (BOP), modified plaque index (mPI), marginal bone loss (MBL), biological and technical complications, complication-free survival and treatment costs. RESULTS: At the 3-year follow-up, 199 patients (Group 1: 67; Group 2: 62; Group 3: 70) were re-examined. Implant survival rates were 91.80%, 97.08% and 100.00% in groups 1, 2 and 3. Implant survival rate in Group 1 was significantly lower than that in Group 3 (p = 0.029). A multivariate Cox model showed that the short-6-mm implants with wide diameter had a protective effect on implant survival (hazard ratio: 0.59, p = 0.001). No significant differences in BOP%, PPD, mPI, MBL and complication-free survival rate were found among the three groups. The average costs of retreatment were 8.31%, 1.96% and 0.56% of the total costs in groups 1, 2 and 3. The cost to avoid a 1% increase in implant loss associated with 6-mm implants over a 3-year period was 369 CNY (56 USD) using a 10-mm implant with OSFE and 484 CNY (74 USD) using an 8-mm implant with OSFE. CONCLUSION: In the moderately atrophic posterior maxillae, the three treatments showed acceptable clinical, radiographic and economic outcomes with up to 3-year follow-up. 10-mm implants combined with OSFE showed more favourable implant survival and fewer maintenance costs in comparison with short-6-mm implants, which were less expensive.

Periodontal regeneration versus extraction and dental implant or prosthetic replacement of teeth severely compromised by attachment loss to the apex: A randomized controlled clinical trial reporting 10-year outcomes, survival analysis and mean cumulative cost of recurrence.

BACKGROUND: Periodontal regeneration can change tooth prognosis and represents an alternative to extraction in teeth compromised by severe intra-bony defects. The aim of this study was to compare periodontal regeneration (PR) with tooth extraction and replacement (TER) in a population with attachment loss to or beyond the apex of the root in terms of professional, patient-reported and economic outcomes. METHODS: This was a 10-year randomized controlled clinical trial. 50 stage III or stage IV periodontitis subjects with a severely compromised tooth with attachment loss to or beyond the apex were randomized to PR or TER with either an implant- or a tooth-supported fixed partial denture. Subjects were kept on a strict periodontal supportive care regimen every 3 months and examined yearly. Survival and recurrence analysis were performed. RESULTS: 88% and 100% survival rates were observed in the PR and TER groups. Complication-free survival was not significantly different: 6.7-9.1 years for PR and 7.3-9.1 years for TER (p = .788). In PR, the observed 10-year attachment gain was 7.3 ± 2.3 mm and the residual probing depths were 3.4 ± 0.8 mm. Recurrence analysis showed that the 95% confidence interval of the costs was significantly lower for PR compared with TER throughout the whole 10-year period. Patient-reported outcomes and oral health-related quality-of-life measurements improved in both groups. CONCLUSIONS: Periodontal regeneration can change the prognosis of hopeless teeth and is a less costly alternative to tooth extraction and replacement. The complexity of the treatment limits widespread application to the most complex cases but provides powerful proof of principle for the benefits of PR in deep intra-bony defect.

Aesthetic assessment after root coverage of multiple adjacent recessions with coronally advanced flap with adjunctive collagen matrix or connective tissue graft: Randomized clinical trial.

BACKGROUND: Few studies have looked at professional assessment or patient perception of aesthetics after root coverage procedures. The addition of connective tissue grafts (CTG) seems to improve aesthetic outcomes. The objective of this a priori analysis was to compare aesthetics after addition of CTG or a collagen matrix (CMX) to coronally advanced flap (CAF). METHODS: Two independent, trained and calibrated assessors analysed baseline and 6-month post-operative Images from 183 subjects with 475 recessions from a previously reported multicentre multinational randomized clinical trial. The root coverage aesthetic score (RES) was assessed in its five constituent components after assessing the suitability of images blindly with regard to treatment assignment and centre. Data were analysed at the tooth and subject level. RESULTS: One hundred and fifty-five subjects (81 CTG) and 393 teeth (207 CTG) were included in the analysis. CTG control subjects had higher total RES scores (mean adjusted difference of 1.3 ± 0.8 RES units, p = 0.002). Analyses of RES subcomponents showed that the CTG group had higher scores in terms of gingival margin position but that better marginal tissue contour (OR 3.0, 95% CI 1.2-7.7) and soft tissue texture (OR 3.3, 95% CI 1.9-5.8) was observed for the CMX group. No significant differences were observed for mucogingival alignment and gingival colour. CONCLUSION: Better overall RES scores were observed for the CTG group. Better marginal tissue texture and marginal contour were observed in the CMX group. More research and development is needed to optimize materials to be used in conjunction with CAF to improve root coverage without negatively affecting tissue texture and marginal contour.

Impact of the global burden of periodontal diseases on health, nutrition and wellbeing of mankind: A call for global action.

BACKGROUND: The global burden of periodontal diseases remains high. Population growth trends, changes in risk factors and improved tooth retention will increase the socio-economic burden of periodontitis that is responsible for 3.5 million years lived with disability, 54 billion USD/year in lost productivity and a major portion of the 442 billion USD/year cost for oral diseases. METHODS: In the context of the Milan World Exhibition 2015 "Feeding the Planet, Energy for Life," a green paper was developed and offered for global consultation by the European Federation of Periodontology. The final draft was endorsed by professional organizations around the world and is presented to stakeholders as a call for global action. RESULTS: Specific actions for the public, policymakers, educators and professional organizations have been identified in the areas of prevention, detection and care. These actions align public interest and knowledge, need for self-care, professional intervention and policies to the best scientific evidence to proactively promote periodontal health and effectively manage the global burden of periodontal diseases, in accordance with WHO/UN priorities and strategies for tackling common non-communicable diseases via the Common Risk Factor Approach. CONCLUSIONS: A strong and coherent body of evidence allows identification of actionable preventive, diagnostic and therapeutic strategies to effectively promote periodontal health and general wellbeing, and better manage the socio-economic consequences. Action requires consideration of the specific national scenarios.

Periodontal regeneration compared with access flap surgery in human intra-bony defects 20-year follow-up of a randomized clinical trial: tooth retention, periodontitis recurrence and costs.

AIM: Compare the long-term outcomes and costs of three treatment modalities in intra-bony defects. MATERIALS AND METHODS: Forty-five intra-bony defects in 45 patients had been randomly allocated to receive: modified papilla preservation technique with titanium-reinforced expanded-polytetrafluoroethylene (ePTFE) membranes (MPPT Tit, N = 15); access flap with expanded-PTFE membranes (Flap-ePTFE, N = 15) and access flap alone (Flap, N = 15). Supportive periodontal care (SPC) was provided monthly for 1 year, then every 3 months for 20 years. Periodontal therapy was delivered to sites showing recurrences. RESULTS: Forty-one patients complied with SPC. Four subjects were lost to follow-up. Clinical attachment-level differences between 1 and 20 years were -0.1 ± 0.3 mm (p = 0.58) in the MPPT Tit; -0.5 ± 0.1 mm (p = 0.003) in the Flap-ePTFE and -1.7 ± 0.4 mm (p < 0.001) in the Flap. At 20 years, sites treated with Flap showed greater attachment loss compared to MPPT Tit (1.4 ± 0.4 mm; p = 0.008) and to Flap-ePTFE (1.1 ± 0.4 mm; p = 0.03). Flap group lost two treated teeth. Five episodes of recurrences occurred in the MPPT Tit, six in the Flap-ePTFE and fifteen in the Flap group. Residual pocket depth at 1-year was significantly correlated with the number of recurrences (p = 0.002). Sites treated with flap had greater OR for recurrences and higher costs of re-intervention than regenerated sites over a 20-year follow-up period with SPC. CONCLUSIONS: Regeneration provided better long-term benefits than Flap: no tooth loss, less periodontitis progression and less expense from re-intervention over a 20-year period. These benefits need to be interpreted in the context of higher immediate costs associated with regenerative treatment. These initial observations need to be extended to larger groups and broader clinical settings.

Primary and secondary prevention of periodontal and peri-implant diseases: Introduction to, and objectives of the 11th European Workshop on Periodontology consensus conference.

BACKGROUND: Periodontitis prevalence remains high. Peri-implantitis is an emerging public health issue. Such a high burden of disease and its social, oral and systemic consequences are compelling reasons for increased attention towards prevention for individuals, professionals and public health officials. METHODS: Sixteen systematic reviews and meta-reviews formed the basis for workshop discussions. Deliberations resulted in four consensus reports. RESULTS: This workshop calls for renewed emphasis on the prevention of periodontitis and peri-implantitis. A critical element is the recognition that prevention needs to be tailored to the individual's needs through diagnosis and risk profiling. Discussions identified critical aspects that may help in the large-scale implementation of preventive programs: (i) a need to communicate to the public the critical importance of gingival bleeding as an early sign of disease, (ii) the need for universal implementation of periodontal screening by the oral health care team, (iii) the role of the oral health team in health promotion and primary and secondary prevention, (iv) understanding the limitations of self-medication with oral health care products without a diagnosis of the underlying condition, and (v) access to appropriate and effective professional preventive care. CONCLUSIONS: The workshop provided specific recommendations for individuals, the oral health team and public health officials. Their implementation in different countries requires adaptation to respective specific national oral health care models.

Risk factor assessment tools for the prevention of periodontitis progression a systematic review.

OBJECTIVES: (i) To identify characteristics of currently published patient-based tools used to assess levels of risk for periodontitis progression and (ii) systematically review the evidence documenting the use of patient-based risk assessment tools for predicting periodontitis progression. MATERIAL AND METHODS: A systematic review was prepared on the basis of an electronic search of the literature supplemented with manually searching the relevant journals of the latest 5 years. Prospective and retrospective cohort studies were included as no randomized controlled clinical trials were available. RESULTS: The search identified 336 titles, and 19 articles were included in this systematic review. The search identified five different risk assessment tools. Results of nine of 10 cohort studies reporting outcomes of 2110 patients indicate that risk assessment tools are able to identify subjects with different probability of periodontitis progression and/or tooth loss. Subjects with higher risk scores showed more progression of periodontitis and tooth loss. CONCLUSIONS: In treated populations, results of patient-based risk assessments, for example periodontal risk calculator (PRC) and periodontal risk assessment (PRA), predicted periodontitis progression and tooth loss in various populations. Additional research on the utility of risk assessment and results in improving patient management are needed.

Periodontal risk assessment (PRA) for patients in supportive periodontal therapy (SPT).

The subject risk assessment may estimate the risk for susceptibility for progression of periodontal disease. It consists of an assessment of the level of infection (full mouth bleeding scores), the prevalence of residual periodontal pockets, tooth loss, an estimation of the loss of periodontal support in relation to the patient's age, an evaluation of the systemic conditions of the patient and finally, an evaluation of environmental and behavioral factors such as smoking. All these factors should be contemplated and evaluated together. A functional diagram may help the clinician in determining the risk for disease progression on the subject level. This may be useful in customizing the frequency and content of SPT visits.

Influence of interleukin-1 gene polymorphism on the outcome of supportive periodontal therapy explored by a multi-factorial periodontal risk assessment model (PRA).

BACKGROUND: Multi-factorial risk models have been proposed to enhance the ability to predict risk for the progression of treated chronic periodontitis. AIMS: to study if the outcomes of supportive periodontal therapy (SPT) based on a multi-factorial periodontal risk assessment are influenced by IL-1 gene polymorphism (IP) status. MATERIAL AND METHODS: Information about the IP and smoking status, clinical periodontal conditions and age related bone level measurements were used to calculate a peridontal risk assessment model (PRA). The surface area of this diagram was calculated for 224 subjects who had participated in an SPT program over four years. Baseline and 4-year follow-up data were studied in relation to the IP status. RESULTS: Positive IP tests were obtained for 80/224 (35.7%) of the subjects. At baseline the mean PRA for the IP positive group was 79.9 units, which at year four had increased to 81.3 units (mean diff: 1.4 units, S.D.+/-16.5, p<0.45, 95% CI: 2.3 to 5.1). At baseline and year four the mean PRA for the IP negative group was 44.2 and 38.6 units, respectively. This difference was statistically significant (mean diff: 5.6, S.D.+/-16.1, p<0.001, 95% CI: 3.0 to 8.3). Independent t-tests confirmed that the IP status was significantly associated with a less favorable change in PRA over the four-year period (PRA difference: 7.04, t=3.01, p<0.003, 95% CI: 2.4 to 11.65). Bleeding on probing, and probing depth values alone did not differ between positive and negative IP status. Regression analysis demonstrated that the best-fit model for change in PRA included bleeding on probing at baseline, IP status, proportional alveolar bone loss in relation to the age, and gender. CONCLUSION: The PRA allowed the assessment of the outcomes of SPT therapy. Subjects with positive IP did not respond to individualized SPT as favorably as did IP negative subjects.