Augmented-reality-assisted intraoral scanning: A proof-of-concept study.

PURPOSE: The aims of the present study were (a) to compare the scanning time and image count to complete optical scans of a typodont between augmented-reality-assisted intraoral scanning (ARIOS) and intraoral scanning (IOS); (b) to compare the accuracy of the digital casts derived from ARIOS and IOS; (c) to compare participant-related outcomes between ARIOS and IOS. MATERIALS AND METHODS: A multi-session within-subject experiment was conducted to compare ARIOS and IOS. Thirty-one dental students participated in the study. Following a trial session, each participant obtained optical scans under ARIOS and IOS conditions. The time required to complete the scan, and the number of images taken were recorded. Participant feedback was collected using entry, exit, and NASA-Task Load Index (TLX) surveys. The accuracy of the digital casts derived from the optical scans was measured in root mean square error (RMSE). RESULTS: The present study found a 6.8% increase in preference for ARIOS from entry to exit survey. Slightly more participants favored the ARIOS setup compared to IOS; 54.8% of participants favored ARIOS, 9.7% were indifferent, and 35.5% favored IOS. NASA-TLX subscale ratings were higher for IOS in general apart from mental demand. The accuracy of the digital casts between ARIOS and IOS was comparable in RMSE. CONCLUSION: ARIOS was advantageous compared to IOS in ergonomics, improved scanner tracking, and ease of scanner orientation. However additional trials, increased field of view, and better superimposition of scanning status to the target site were improvements desired by the study participants.

Extended porcelain veneers in the maxillary anterior region. A retrospective study with an up to 27-year follow-up

AIM: The aim of the present retrospective study was to evaluate the long-term results, including technical and biologic outcomes, of maxillary extended porcelain veneers with an incisal edge thickness above 2 mm. MATERIALS AND METHODS: Patients treated with extended porcelain veneers performed by a single clinician at University of Geneva between 1990 and 2003 were identified and invited to an examination. Of the 37 identified patients, 10 patients with 50 veneers agreed to be examined and were included. A clinical examination was performed to assess survival rates as well as technical and biologic outcomes (modified United States Public Health Services criteria). Patient records were also reviewed to retrieve patient and reconstruction data and every complication event. Patient-reported outcome measures (PROMs) were evaluated using a visual analog scale to measure esthetic satisfaction, functional and phonetic comfort, masticatory improvement, tooth sensitivity, and acceptance of restoration replacement in case of failure. Data were descriptively analyzed, and Kaplan-Meier survival estimators were computed for survival rates and complication events. RESULTS: The survival rate of the veneers was 96% after a mean follow-up of 20.7 ± 3.7 years in function. The technical complication rate amounted to 30%, including two failures, nine repairable fractures, three cracks, and one displacement due to trauma. No cavitated caries lesions or endodontic complications were registered. PROMs were very high for esthetic satisfaction and phonetic comfort. CONCLUSIONS: Within the limitations of the present retrospective study, extended porcelain veneers appear to be a successful long-term treatment option in terms of clinical outcomes and patient satisfaction.

Are periodontitis and dental caries associated? A systematic review with meta-analyses.

AIM: The epidemiological relationship between periodontitis and caries remains controversial, and evidence synthesis is currently lacking. Therefore, this systematic review was designed to answer the following PECO question: 'In human adults (P), do subjects suffering from periodontitis (E) have higher presence/number of untreated carious lesions and caries experience (O) than subjects not suffering from periodontitis (C)?'. MATERIALS AND METHODS: Observational studies that met specific inclusion criteria established to answer to the PECO question were included. Two review authors independently searched for eligible studies, screened the titles and abstracts, carried out the full text analysis, extracted the data and performed the risk of bias assessment. In case of disagreement, a third review author took the final decision during ad hoc consensus meetings. Data synthesis was carried out through random-effects meta-analyses. RESULTS: A total of 18 studies on 21 cohorts, involving 135,018 participants, were included. Meta-analyses showed a significant association between periodontitis and the presence of at least one tooth with either untreated carious lesions (odds ratio [OR] = 1.63; 95% confidence interval [CI]: 1.32-2.01; p <.00; I2 = 83.0%) or caries experience (decayed and filled teeth ≥ 1) (OR = 1.27; 95% CI: 1.01-1.59; p = .038; I2 = 90.0%). Moreover, subjects with periodontitis exhibited a higher number of surfaces (difference in means [MD] = 0.86; 95% CI: 0.46-1.27; p <.001; I2 = 0.0%) and teeth (MD = 0.35; 95% CI: 0.28-0.42; p <.001; I2 = 69.6%) with untreated carious lesions, as well as a higher number of teeth with caries experience (standardized difference in means [SMD] = 1.46; 95% CI: 0.15-2.78; p = .029; I2 = 98.9%) compared with those without periodontitis. Sensitivity analyses focusing on severe periodontitis as exposure mostly showed consistent results. Estimates for caries experience were only slightly attenuated in adjusted models compared with crude models. Subgroup analyses by caries location also indicated that periodontitis was associated only with root caries, while it was not with caries affecting the anatomical crown. CONCLUSIONS: Periodontitis was found to be associated with the presence and number of treated/untreated root carious lesions. Therefore, caries-specific preventive measures (e.g., fluorides) should be considered for individuals with periodontitis.

Hormone-related events and periodontitis in women.

AIM: While the short-term effects of hormonal events on gingival inflammation have been well described, long-term effects on the periodontium have received less attention. The aim of this cross-sectional population-based study was to evaluate the association between hormone-related events and periodontitis in a representative sample of the postmenopausal women of South Korea. MATERIALS AND METHODS: A total of 10,273 postmenopausal women representative of 6.1 million of Koreans were examined. Periodontitis and severe periodontitis were defined according to the Community Periodontal Index (CPI â‰§ 3 and CPI = 4, respectively). Univariate and multivariate regression analyses using 3 different models were applied controlling for age, smoking, marital status, educational level, income, BMI, hypertension, stress and frequency of toothbrushing. RESULTS: Severe periodontitis was directly associated with a longer reproductive life (p-trend = .027) and with a longer duration of breastfeeding (48-72 vs. 1-17 months: OR = 1.49; 95% CI: 1.01-2.21). Conversely, early menopausal age (<46 vs. 49-50 years: OR = 0.74; 95% CI: 0.56-0.97), history of artificial menopause (OR = 0.72; 95% CI: 0.53-0.97), having had more than 6 pregnancies (vs. 4: OR = 0.73; 95% CI: 0.55-0.97), having had more than three abortions (vs. 0: OR = 0.51; 95% CI: 0.28-0.93) and having had the first birth age >26 years (vs. <21 years: OR = 0.71; 95% CI: 0.52-0.97) were inversely associated with severe periodontitis. CONCLUSIONS: In this large nationally representative population, severe periodontitis was related to menopausal age, reproductive life length, number of pregnancies/abortions, first birth age and breastfeeding duration, while it was not to oral contraceptive and hormone replacement therapy usages.

Periodontitis and platelet count: A new potential link with cardiovascular and other systemic inflammatory diseases.

AIM: As an infection-driven inflammatory disease, periodontitis could lead to a reactive increase in platelet count. This mechanism could partially mediate the well-documented association between periodontitis and atherosclerotic cardiovascular disease. The aim of this cross-sectional study was to test the presence of an association between periodontitis and platelet count in a representative sample of the South Korea population. MATERIALS AND METHODS: A total of 5,197 subjects representative of 34.9 million of adults were examined. Multivariate regression analyses were applied controlling for age, gender, smoking status, educational level, body mass index, alcoholism, diabetes and hypertension status, vitamin D serum levels and total cholesterol, triglycerides, HDL and LDL blood levels. RESULTS: Compared to the non-severe periodontitis group, subjects with severe periodontitis (CPI = 4) displayed 13,048.93 more platelets for µl of blood (95% CI: 3,296.26-22,801.61, p = 0.009) in the fully-adjusted model. The association between severe periodontitis and platelet count has shown to be highlighted in subjects aged more than 60 years, females, non-smokers and with normal HDL blood levels. A systemic inflammatory biomarker (white blood cell count) explained the 19.25% of this association. CONCLUSIONS: Within the limitations of this study, periodontitis-especially severe-is independently associated with a considerable increase in platelet count which is explained, at least in part, by an increase in the systemic inflammation.