Comparing intraosseous computerized anaesthesia with inferior alveolar nerve block in the treatment of symptomatic irreversible pulpitis: A randomized controlled trial.

AIM: The aim of this study was to compare the cardiovascular effects [heart rate, oxygen saturation (SpO2 ), systolic and diastolic blood pressure] and the anaesthetic efficacy of intraosseous computerized anaesthesia (ICA) versus inferior alveolar nerve block (IANB) in Symptomatic irreversible pulpitis (SIP). METHODOLOGY: The study protocol was registered with ClinicalTrials.gov (NCT03802305). In a randomized, prospective clinical trial, 72 mandibular molar teeth with SIP were randomly allocated to conventional IANB injection (n = 36) or ICA injection (n = 36), both with 1.8 mL of 4% articaine with 1:100 000 epinephrine. The primary objective was to assess the cardiovascular parameters (heart rate, oxygen saturation, blood pressure) before, during and after the anaesthesia. The secondary objectives were to compare ICA with IANB for success and postoperative outcomes for up to 3 days. RESULTS: The maximum increase in heart rate in the ICA group was greater than in the IANB. Other cardiovascular parameters did not show differences throughout the clinical procedure. There were no statistically significant differences (p > .05) between groups for sex, age, or anxiety. The total success rate of ICA (91.43%) was significantly higher (p = .0034) than that of IANB (69.44%). CONCLUSIONS: This study establishes that ICA is safe and efficient in the first intention for the treatment of SIP of the mandibular molar.

Effect of Reinforced Oral Hygiene on Periodontally Healthy Dental Students: A Four-year Follow-up Clinical Trial.

PURPOSE: In periodontally healthy individuals, mean crevicular depth ranges from 1 to 3 mm. This depth threshold has been used as an indicator to differentiate a physiological dentoalveolar sulcus from a periodontal pocket needing further treatment. Because many studies have shown the important contribution of oral hygiene status to periodontal health, the purpose of this study was to explore the clinical effect of reinforced oral hygiene on the periodontal status of periodontitis-free dental students. MATERIALS AND METHODS: In our longitudinal observational clinical study, we assessed the periodontal status of healthy individuals attending the dental school by measuring the periodontal pocket depth, bleeding on probing, and plaque index. The follow-up reassessment was carried out four years later at the end of the dental curriculum. RESULTS: The study showed that oral hygiene improvement led to a slight but significant reduction in the mean sulcus depth (-0.049 mm; p<0.0001). CONCLUSIONS: Reinforcement of oral hygiene contributes to the reduction of probing depth even in periodontally healthy patients.

Assessment and Quantification of Noncollagenic Matrix Proteins Released from Human Dentin Powder Incorporated into a Silated Hydroxypropylmethylcellulose Biomedical Hydrogel.

INTRODUCTION: The dentin extracellular matrix is a reservoir of bioactive molecules sequestered into dentin during dental initial development. They can be released under pathological conditions but also by controlled demineralization with bioactive materials. The purpose of this study was to investigate the ability of a biomedical hydrogel to extract and release these proteins from smashed dentin. METHODS: Smashed dentin was obtained with 2 different kinds of grinders: a blade mill and a zirconia mortar grinder. The particle size was measured by scanning electron microscopy. Dentin powder was incorporated into a silated hydroxypropylmethylcellulose hydrogel. Several types of mixtures with variable parameters were tested. The mixtures were immersed into phosphate-buffered saline. The supernatants were collected, and the total released proteins were quantified by gel shift migration and Coomassie staining. The presence of transforming growth factor beta 1 was investigated by Western blot analysis and the ELISA. RESULTS: The mixture dentin powder/hydrogel released proteins (from 49.1 µg/mL-137.9 µg/mL according to the mixtures). The release kinetics was growing and started from the first day until stabilization at 14 days. The quantity of released proteins was directly related to the size of the particles and the weight of the powder incorporated into the hydrogel. Gel shift with direct revelation by ultraviolet and Western blot analyses confirmed the presence of transforming growth factor beta 1 using ELISA. CONCLUSIONS: We showed that silated hydroxypropylmethylcellulose hydrogel was able to extract dentin matrix proteins from smashed dentin powder. This mixture could be considered a new way of dental treatment for the dentin-pulp complex and bone regeneration.

A recall program for the outcome of conventional root canal treatment performed in a teaching hospital.

OBJECTIVES: This study investigated the long-term survival and the prognostic factors of endodontic treatments performed in a dental teaching hospital. The aim was to calculate the probabilities of success or failure according to the follow-up extent and to assess the time allowed for a complete periapical healing. MATERIALS AND METHODS: A cohort of 185 teeth were re-examined 1-4 years after treatment. The outcome was assessed on the basis of radiographic and clinical criteria as success, uncertain or failure. A survival analysis using the Cox model was used (i) to explore tooth survival and periapical healing over the time and (ii) to highlight the predictive factors of treatment outcome. RESULTS: After 2 years, the appearance of an apical periodontitis remained lower than 3.5%, whereas only 22.8% of periapical healed cases were notified. The prognosis factors are: (i) for teeth with initial healthy periapical conditions, coronal leakage (p = 0.002) with the higher risk of failure (RR = 19.77), absence of correspondence filling length/shaping = 0.026), type of teeth (p = 0.041) and (ii) for teeth with apical periodontitis, number of root canals (p = 0.000,91), correspondence filling length/shaping length (p = 0.017) and over-filling (p = 0.09). New periapical lesions or tooth loss were recorded after 2 years. Half of the successful cases of periapical healing were observed during the follow-up from 2-4 years. CONCLUSIONS: This longitudinal study shows that coronal leakage is responsible for late failure and that periapical healing is long to achieve. Therefore, endodontic treatments may require a follow-up of over 2 years.

Bioactive materials in endodontics.

Endodontic treatment in dentistry is a delicate procedure and many treatment attempts fail. Despite constant development of new root canal filling techniques, the clinician is confronted with both a complex root canal system and the use of filling materials that are harmful for periapical tissues. This paper evaluates reported studies on biomaterials used in endodontics, including calcium hydroxide, mineral trioxide aggregate, calcium phosphate ceramics and calcium phosphate cements. Special emphasis is made on promising new biomaterials, such as injectable bone substitute and injectable calcium phosphate cements. These materials, which combine biocompatibility, bioactivity and rheological properties, could be good alternatives in endodontics as root canal fillers. They could also be used as drug-delivery vehicles (e.g., for antibiotics and growth factors) or as scaffolds in pulp tissue engineering.

Osteoblastic cell behaviour on different titanium implant surfaces.

The osseointegration of oral implants is related to the early interactions between osteoblastic cells and titanium surfaces. The behaviour of osteoblastic MC3T3-E1 cells was compared on four different titanium surfaces: mirror-polished (Smooth-Ti), alumina grit-blasted (Alumina-Ti) or biphasic calcium phosphate ceramic grit-blasted (BCP-Ti) and a commercially available implant surface (SLA). Scanning electron microscopy and profilometry showed distinct microtopographies. The BCP-Ti group had higher average surface roughness (Ra=2.5 microm) than the other grit-blasted groups. Hydrophilicity and surfaces energies were determined on the different substrates by dynamic contact angle measurements. The most hydrophilic surface was the Alumina-Ti discs, while SLA was the most hydrophobic. The titanium surfaces were all oxidized as TiO2 and polluted by carbon contaminants, as determined by X-ray photoelectron spectroscopy. Alumina-Ti samples also exhibited aluminium peaks as a result of the blasting. The BCP-Ti discs contained traces of calcium and phosphorus. MC3T3-E1 cells attached, spread and proliferated on the substrates. For both the SLA and BCP-Ti groups, the entire surface was covered with a layer of osteoblastic cells after 2 days. At high magnification, the cells exhibited cytoplasmic extensions and filopodia. Compared with plastic, cell viability was similar with the Smooth-Ti, slightly lower with the Alumina-Ti and superior with the SLA and BCP-Ti groups. Alkaline phosphatase activity increased with the culture time whatever the substrate. This study shows that BCP-blasting produces rough titanium implants without surface contaminants.