Prosthetic Surgical Templates and Dental Implant Site Time Preparation: An In Vitro Study

Relationship between sublingual varices and hypertension: a systematic review and meta-analysis

BACKGROUND

Previous research has investigated the connection between sublingual varices (SV) and cardiovascular disease, aging, and smoking. However, it is still unclear whether arterial hypertension affects the presence of SV. This meta-analysis aimed to investigate the relationship between hypertension and the presence of SV.

METHODS

The literature search was performed using PubMed, Web of Science, Scopus, Google Scholar, and Embase for cross-sectional studies until July 2023. PRISMA guidelines were used for article selection. A meta-analysis using standardized mean differences by a random effects model was conducted to pool studies.

RESULTS

A total of 568 articles were retrieved, of which twelve were included in the meta-analysis. Cumulatively, 2543 samples in the case group (1185 with hypertension) and 3897 samples (821 with hypertension) were studied in the control group. Using the random effects model, the pooled odds ratio (OR) revealed a significant association between hypertension and sublingual varices (OR = 2.66; 95% CI: 1.69-4.18).

CONCLUSION

The meta-analysis showed a significant and positive association between sublingual varices and hypertension. SV's presence could be used by dentists as a non-invasive indicator of hypertension screening.

Advancing accuracy in guided implant placement: A comprehensive meta-analysis: Meta-Analysis evaluation of the accuracy of available implant placement Methods

OBJECTIVES

This meta-analysis aimed to determine the accuracy of currently available computer-assisted implant surgery (CAIS) modalities under in vitro conditions and investigate whether these novel techniques can achieve clinically acceptable accuracy.

DATA

In vitro studies comparing the postoperative implant position with the preoperative plan were included. Risk of bias was assessed using the Quality Assessment Tool For In Vitro Studies (QUIN Tool) and a sensitivity analysis was conducted using funnel plots.

SOURCES

A systematic search was performed on April 18, 2023, using the following three databases: MEDLINE (via PubMed), EMBASE, and Cochrane Central Register of Controlled Trials. No filters or restrictions were applied during the search.

RESULTS

A total of 5,894 studies were included following study selection. Robotic- and static CAIS (sCAIS) had the most accurate and clinically acceptable outcomes. sCAIS was further divided according to the guidance level. Among the sCAIS groups, fully guided implant placement had the greatest accuracy. Augmented reality-based CAIS (AR-based CAIS) had clinically acceptable results for all the outcomes except for apical global deviation. Dynamic CAIS (dCAIS) demonstrated clinically safe results, except for horizontal apical deviation. Freehand implant placement was associated with the greatest number of errors.

CONCLUSIONS

Fully guided sCAIS demonstrated the most predictable outcomes, whereas freehand sCAIS demonstrated the lowest accuracy. AR-based and robotic CAIS may be promising alternatives.

CLINICAL SIGNIFICANCE

To our knowledge, this is the first meta-analysis to evaluate the accuracy of robotic CAIS and investigate the accuracy of various CAIS modalities.

Is there any difference based on sublingual varices frequency between hypertensive patients and healthy persons?

BACKGROUND

Sublingual varices (SV) are benign vascular lesions that have questionable associations with aging, smoking, and hypertension. This study purposed to evaluate whether SV frequency differs between hypertensive patients and healthy persons.

METHODS AND MATERIAL

This cross-sectional study was conducted on 120 dental patients referred to Yazd Oral Medicine Department. At first sublingual surface of the tongue were examined before the routine oral survey, and blood pressure (BP) was measured in a sitting position. SV were classified into Grade 1 (no/mild), Grade 2 (medium to severe), and Grade 3 (multi-focal). Blood pressure was measured in all participants. Participants based on the obtained BP, divided into normal, prehypertension, stage 1, and 2 groups. Frequency of SV was compared in regarding age, gender, and stage of hypertension. All of the analyses were conducted at a p < 0.05 level of significance by the SPSS22 statistical package using chi-square test.

RESULTS

Out of 120 patients, 84 (70%) had SV. The frequency of SV in patients with hypertension (HT) (86.8%) was significantly higher than in others (48.1%); (p < 0.001). Data analysis showed there was a significant difference between the age groups. There was no significant difference based on SV between two genders. There was no significant difference in the frequency of sublingual varices between males and females. Aging could impact the frequency of SV.

CONCLUSION

This study revealed that patients with hypertension had more SV. A simple valuable method for dental clinicians to be active in preventive health care is evaluating sublingual surface of tongue.

Influence of alveolar ridge morphology and guide-hole design on the accuracy of static Computer-Assisted Implant Surgery with two implant macro-designs: An in vitro study

OBJECTIVES

The primary aim of this in vitro study was to evaluate the influence of alveolar ridge morphologies on the accuracy of static Computer-Assisted Implant Surgery (sCAIS). The secondary aims were to evaluate the influence of guide-hole design and implant macro-design on the accuracy of the final implant position.

METHODS

Eighteen standardized partially edentulous maxillary models with two different types of alveolar ridge morphologies were used. Each model was scanned via cone beam computer tomography prior to implant placement and scanned with a laboratory scanner prior to and following implant placement using sCAIS. The postsurgical scans were superimposed on the initial treatment planning position to measure the deviations between planned and postsurgical implant positions.

RESULTS

Seventy-two implants were equally distributed to the study groups. Implants placed in healed alveolar ridges showed significantly lower mean deviations at the crest (0.36 ± 0.17 mm), apex (0.69 ± 0.36 mm), and angular deviation (1.86 ± 0.99°), compared to implants placed in fresh extraction sites (0.80 ± 0.29 mm, 1.61 ± 0.59 mm, and 4.33 ± 1.87°; all p<0.0001). Implants placed with a sleeveless guide-hole design demonstrated significantly lower apical (1.02 ± 0.66 mm) and angular (2.72 ± 1.93°) deviations compared to those placed with manufacturer's sleeves (1.27 ± 0.67 mm; p = 0.01, and 3.46 ± 1.9°; p = 0.02). Deep-threaded tapered bone level implants exhibited significantly lower deviations at the crest (0.49 ± 0.28 mm), apex (0.97 ± 0.63 mm), and angular deviations (2.63 ± 1.85°) compared to shallow-threaded parallel-walled bone level implants (0.67 ± 0.34 mm; p = 0.0005, 1.32 ± 0.67 mm; p = 0.003, and 3.56 ± 1.93°; p = 0.01).

CONCLUSIONS

The accuracy of the final implant position with sCAIS is determined by the morphology of the alveolar ridge, the design of the guide holes, and the macrodesign of the implant.

CLINICAL SIGNIFICANCE

Higher accuracy in the final implant position was observed with implants placed in healed alveolar ridge morphologies, in implants with deep-threaded tapered macro-design, and when sleeveless surgical guide holes were used.

Surgical Margins in 3D Planned Mandibular Resections for Squamous Cell Carcinomas of the Oral Cavity

PURPOSE

Three-dimensional (3D) planned mandibular resections using cutting guides and preplanned plates are now widely used in oncological surgery. The main advantages are the gain of time, precision, and esthetic outcomes. The drawbacks include costs, time for planning, and printing the surgical tools. This time between the radiological data and the surgery may allow tumor progression, rendering the custom-made guides useless. There is no consensus regarding surgical margins that should be planned to ensure a safe oncologic outcome. The purpose of this retrospective study is to evaluate if the planned bony margins are adequate.

MATERIALS AND METHODS

Inclusion criteria were: Squamous cell carcinomas of the anterior and lateral floor of mouth with mandibular invasion (T4); mandibular resection using 3D planning and cutting guides. Between June 2015 to December 2019, 16 patients met the criteria. The time between the planning and the surgery was recorded. The authors decided to use a margin of at least 1 cm on the preoperative computerized tomography scans on each side of the tumors in our planning for all patients. The authors then measured the distance of the bone resection on the pathological specimen.

RESULTS

All 16 patients had safe bone surgical margins (R0). The average time from the scanners used for the planning to the surgery was 33 days.

DISCUSSION

All the cutting guides could be used. The pathology examination showed safe oncological margins and no patients required further resection. A 1 cm margin during 3D planning for mandibular resections with 3D printed cutting guides, in patients with T4 Squamous Cell Carcinomas can therefore be considered safe.

Antibacterial Effects of Curcumin Nanocrystals against Porphyromonas gingivalis Isolated from Patients with Implant Failure

Background. Despite their benefits, dental implants may sometimes fail for a diversity of causes; the most common reasons of failure are infection and bone loss. Porphyromonas gingivalis (P. gingivalis) bacteria show a major role in peri-implantitis infection and dental implant failure. Methods. In this study, the prevalence of P. gingivalis isolated from the gingival crevicular fluid (GCF) of fifteen Iranian patients with implant failure (more than 1/3 of the implant length), who had average oral and dental hygiene and no antibiotic use for at least one month, was determined. Moreover, the antimicrobial effects of curcumin nanocrystals against isolated P. gingivalis were investigated. The collected samples from patients were transferred to a microbiology laboratory to culture. The presence of P. gingivalis in the culture media was confirmed using a trypsin reagent test. An isolate from a patient with the highest colony count was selected to evaluate the antibacterial effects of curcumin nanoparticles. The inhibition zone diameter, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were determined. Results. Out of fifteen patients, eight (53.33%) were positive for the presence of P. gingivalis. The results of the microbial tests showed that curcumin nanoparticles had an MIC of 6.25 µg/mL and an MBC of 12.5 µg/mL. Conclusions. The use of curcumin nanoparticles may control the bacterial infection around the implant.

In Silico Contact Pressure of Metal-on-Metal Total Hip Implant with Different Materials Subjected to Gait Loading

The use of material for implant bearing has a vital role in minimizing failures that endanger implant recipients. Evaluation of contact pressure of bearing material can be the basis for material selection and have correlations with wear that contribute to the need of revision operations. The current paper aims to investigate three different metallic materials, namely cobalt chromium molybdenum (CoCrMo), stainless steel 316L (SS 316L), and titanium alloy (Ti6Al4V) for application in metal-on-metal bearing of total hip implant in terms of contact pressure. In silico model based on finite element simulation has been considered to predict contact pressure of metal-on-metal bearings under normal walking conditions. It is found that the use of Ti6Al-4V-on-Ti6Al4V is superior in its ability to reduce contact pressure by more than 35% compared to the other studied metal-on-metal couple bearings.

Digital Workflow for Prosthetically Driven Implants Placement and Digital Cross Mounting: A Retrospective Case Series

Fully digital workflow in implant dentistry is ever increasing. Treatment of partial edentulous cases is well-documented; nevertheless, complete edentulous cases are still a challenge. To present several innovations in the treatment of complete edentulous patients using digital solutions, both for implant placement and restoration delivery, was the objective of this study. It was designed as a retrospective case series study, aimed to tune further research with larger sample size, and a longer follow-up. Patients requiring complete, implant-supported restoration were asked to participate in this study. Enrolled patients were treated with four implants, immediate loading and a definitive complete arch restoration. Patients were treated using computer-assisted, template-based surgery. Multi-piece surgical templates were used to accurately place the implants, to manage the bone if needed and to make immediate loading procedure quicker and easier. After osseointegration period, definitive, extra-oral, digital impressions were taken using newly developed scan analogs, connected in the patient mouth using temporary cylinders and stabilized by means of the low-shrinkage, flowable, resin composite. Outcomes were implant and prosthesis survival rate, complications, accuracy, and patient satisfaction. Radiographic evaluation performed with a preliminary, radiopaque aluminum try-in, was used to test the accuracy of the digital impressions. Overall, 20 implants were placed in five patients. All the implants osseointegrated without complications. One impression was taken a second time due to inaccuracy of the aluminum tray-in. Finally, all of the patients were completely satisfied with both surgical and prosthetic procedures. Within the limitations of this case series, multi-piece surgical templates showed promising results improving the clinician’s confidence in the case of bone reduction, post-extractive implants and immediate loading. The prosthetic template increased the trueness of the digital impression for complete edentulous patients. Finally, even if an impression was performed again, the scan-analog used for extra-oral chair-side digital impressions seemed to be a promising tool. Continuous improvements and further study are needed to confirm these preliminary results.