Acta Stomatologica Croatica最新文献

Introduction: Radiotherapy is used to treat neo plasmatic lesions and the common side effects of this process are pain, swelling and sensitivity of mucous membranes in domain of radiation, reduced salivation, caries, and periodontal disease and, in total, low life quality. The purpose of this research was to estimate the outcome of direct irradiation on physical and surface characteristics of hard dental tissues.

Materials and methods: Twenty, caries free third molars were involved in the research. Prior to different submission protocols, tooth halves were randomly assigned to subject and control groups by using a draw method. The first group (n=20) was submitted to conventional irradiation protocol (2 Gy for 35 days), second group (n=20) was submitted to one powerful, exploratory dose of 70 Gy. Each sample served as its own control. Radiation was performed with a linear accelerator radiotherapy unit. The surface microhardness and roughness were measured at the beginning (initially), and upon completion of irradiation procedure. The average change in microhardness and roughness after different treatments was compared by t-test for independent samples. Normality was tested by the Shapiro-Wilk test.

Results: Significant differences were found after the standard radiation protocol and the exploratory dose of 70 Gy, with decreased mean microhardness and increased mean roughness (p<0.001) of both hard dental tissues. Enamel and dentin surface microhardness and roughness did not vary notably with regards to different irradiation protocols.

Conclusion: Head and neck conventional irradiation protocol leads to possible breakdown of enamel and dentin with reduced microhardness and increased surface roughness regardless of used irradiation protocol.

Objective: The purpose of this case report was to present a method for the assessment of volumetric changes of bone blocks during healing and demonstrate its practicability by analysing the resorption of a pre-shaped allogeneic bone block used for the reconstruction of a complex maxillary defect.

Materials and methods: CBCT-scans of a 19-year-old male treated with an allogeneic bone block were recorded pre-OP, post-OP, and following six months of healing. Graft shrinkage was assessed via two image matching tools, namely coDiagnostiX® and Slicer. A biopsy specimen was harvested along the implant canal at the time of implantation.

Results: The osseous defect was successfully restored and advanced graft remodelling was found upon re-entry as confirmed by the histomorphometric and histologic analysis. The initial volumes of the graft determined via coDiagnostiX® and Slicer were 0.373 mL and 0.370 mL., respectively, while graft resorption after six months of healing was 0.011 mL (3.00%) and 0.016 mL (4.33%).

Conclusions: The avoidance of bone harvesting and reduction of invasiveness display an important issue in dentoalveolar restorations. However, before grafting materials can be considered a safe alternative, understanding their clinical performance, especially resorption stability, is pivotal. The present case report demonstrates a limited resorption of the allogeneic bone block and further emphasizes the practicability of determining bone resorption by the here introduced method. As our investigation comprises solely one subject, the results should be considered with care and substantiated by further studies.

Objectives: The aim of this research was to evaluate the effect of long-term use of three intracanal medicaments on the radicular dentin microhardness and fracture resistance.

Material and methods: A chemomechanical preparation was done using the Protaper rotary instruments up to F3. The teeth were stored in an incubator at 37°C at 100% humidity and were categorized in three groups by random allocation, namely: Triple Antibiotic Paste (TAP), Calcium hydroxide paste (Apexcal) and Ledermix. Following medicament application, the access openings of all teeth were sealed with 4 mm thickness of cavit. The samples were stored for periods of 1 week, 1 month and 3months. Two dentin cylinders measuring 5mm and 3mm were obtained from each sample. The cervical third was used for fracture resistance and the middle third was used for micro hardness evaluation. The microhardness testing was done using a Knoop microhardness tester, and the fracture resistance testing was done using the universal testing machine.

Results: Calcium hydroxide showed maximally negative effect on the physical properties of radicular dentin compared to TAP (p= 0.0100 at one month and Ledermix (p=0.0001 at one month). With an increase in the application time, there was an increased deterioration in the physical properties of radicular dentin.

Conclusion: Long-term placement of calcium hydroxide, Triple Antibiotic Paste, and Ledermix (p= 0.0001at 3 months) significantly affects the microhardness and fracture resistance of radicular dentin.

Introduction: Hydrophilicity of dental impression materials is crucial for obtaining an accurate impression and necessary for the production of a well-fitting cast restoration. The most common technique for evaluation of hydrophilicity is a contact angle measurement. The aim of the present in vitro study was to compare the water contact angles of four groups of elastomeric impression materials, before and during setting.

Material and methods: Flattened specimens (n=10) of tested impression materials were prepared by the use of a Teflon mold with specific dimensions. A 5μl droplet of deionized water fell on the specimen, and photos were taken using a Nikon D3200 DSLR camera and a 105 mm macro lens (Nikorr, Nikon) in specific time points.

Results: The CAD/CAM material showed the highest contact angle measurements. The light body polyvinylsiloxane (PVS) material 1, polyether and vinylsiloxanether material showed comparable contact angle measurements especially at the initial time point. A statistically significant reduction of contact angles was reported during setup time for all PVS, PE and vinylsiloxanether materials, while the most expressed reduction of contact angle measurements, and thus the most significant increase of hydrophilicity were reported for light wash PVS material 2.

Conclusions: The CAD/CAM impression material showed the most hydrophobic behavior. PVS materials showed excellent hydrophilicity. Polyether and polyvinyloxanether impression materials presented lower contact angle measurements, and thus superior hydrophilicity, compared with other tested materials initially and during setting. All tested impression materials presented a stepwise development of hydrophilicity during the setting stage.

Objective of work: Wrong-site tooth extraction (WSTE) is the most common serious patient safety incident in dentistry. Safety checklists have significantly reduced wrong-site surgery, although their benefit is unproven in primary care dentistry. Our quality improvement project developed and implemented a checklist optimised for oral surgery procedures in primary care to reduce WSTE risk.

Material and methods: Local best practice for tooth extraction record-keeping (LBP), using national guidelines and standards was devised. We then retrospectively audited tooth extraction record-keeping against LBP. Deficiencies in current record-keeping practice were identified and used to design a checklist aimed at improving compliance. We provided a computerised safety checklist compliant with LBP to eleven clinicians at three general dental clinics within our region. The checklist included a pre-operative safety check, a pause to re-confirm the surgical site and a post-operative record-keeping proforma. The checklist was linked to our record-keeping software for use during tooth extraction. We audited checklist completion and compliance with LBP fortnightly for ten weeks.

Results: The introduction of a safety checklist resulted in increased compliance with LBP for tooth extraction record keeping. At week ten, 67% of records contained the computerised safety checklist. This resulted in a 50% increase in overall compliance with LBP for tooth extraction compared to baseline.

Conclusions: A computerised safety checklist for tooth extraction in primary care has potential to improve patient safety by adopting measures to prevent WSTE and standardising communication between clinicians. Checklists in general practice should be encouraged.

Objective: To assess whether there are differences in skeletal maturation among subjects with horizontal, vertical, and neutral facial growth patterns.

Material and methods: The study was performed on 48 latero-lateral craniographs of patients with horizontal, 48 with vertical and 50 with neutral growth patterns aged 12 to 18 years. Eight variables from the Zagreb 82 MOD, Bracchetti and Accord analysis, were selected for measuring angular and linear parameters on latero-lateral craniographs. The assessment of skeletal maturation was done by using the CVMS method.

Results: Statistical analysis showed significant differences in skeletal maturity (p <0.001) between subjects with horizontal and vertical growth pattern and between the subjects with neutral and vertical growth pattern (p <0.05), while no significant difference was found between patients with horizontal and neutral growth pattern. In the younger group (12 - 15 years) there was a statistically significant difference (p <0.05) among subjects with horizontal and vertical growth patterns. In the older group (16 - 18 yrs) there was a statistically significant difference (p > 0.05) in skeletal maturity among subjects with vertical growth patterns compared with horizontal and neutral. In terms of stages of skeletal maturity, patients with a horizontal and neutral growth pattern in the younger group were on average in the fourth stage, and those with a vertical growth pattern in the third stage. In the older group, patients with a horizontal and neutral growth pattern were on average in the fifth stage of skeletal maturity and those with a vertical growth pattern in the fourth stage.

Conclusion: According to the growth pattern, patients differ in the stage of skeletal maturity.

Objectives: The aim of this clinical study was to compare tooth sensitivity scores and color change values before and 1 day following whitening treatments using different concentrations of whitening agents for in-office and at-home procedures.

Materials and methods: A total of 60 participants divided into 3 groups were included in this study. A whitening procedure was carried out in groups using 40% hydrogen peroxide (HP) in in-office treatment, 16% and 10% carbamide peroxide (CP), respectively. Participants rated their tooth sensitivity at the baseline and 1 day following the treatment. The CIEl_ab values were recorded and color differences were calculated.

Results: Within each of the whitening treatments, the tooth sensitivity scores significantly increased following the procedure (p<0.05). The largest significant increase in scores was noted in 40% HP in-office whitening treatment, while the lowest increase was noted in 10% CP at-home whitening treatments (p<0.05). The highest color change 1 day following the procedure was found in the 40% HP in-office whitening treatment group (3.3) and it significantly differed from both 16% CP and 10% CP at-home whitening treatments whose color difference was both 2.0, respectively (p<0.05).

Conclusion: 1 day following the procedure, a low concentrate CP agent for at-home whitening causes the least tooth sensitivity compared to higher concentrate CP for at-home and HP for in-office agents, with the same color change efficacy as higher concentrate CP agent. In case with slight tooth sensitivity reported at the baseline, a 10% CP whitening treatment should be recommended.

The mesiodens is the most frequent type of supernumerary tooth which can appear in the maxillary midline area. The etiology of mesiodentes is not fully understood. This report shows a case of incomplete fusion of an unerupted mesiodens with a permanent maxillary central incisor, aligned in the dental arch. Intraoral and radiographic examinations indicated fusion of the crown and cervical part of the root of the supernumerary tooth with the permanent incisor. The clinical situation was further complicated by the presence of another supernumerary tooth located palatally. The treatment approach has included two phase surgical therapy to extract the supernumerary teeth. Early diagnosis and appropriate surgical treatment of mesiodentes are important to decrease the risk of clinical complications. Pre-operative 3D imaging is strongly advisable since it allows accurate data to be obtained, and reduces the extent of surgery and the possibility of procedural complications. In most cases, a multidisciplinary collaboration is necessary for precise diagnosis and predictable treatment outcome.