A Molecular Approach for Detecting Bacteria and Fungi in Healthcare Environment Aerosols: A Systematic Review.

Molecular methods have become integral to microbiological research for microbial identification. This literature review focuses on the application of molecular methods in examining airborne bacteria and fungi in healthcare facilities. In January 2024, a comprehensive electronic search was carried out in esteemed databases including PubMed, Web of Science, and Scopus, employing carefully selected keywords such as ((bacteria) OR (virus) OR (fungi)) AND (aerosol) AND ((hospital) OR (healthcare) OR (dental office)) AND ((molecular) OR (PCR) OR (NGS) OR (RNA) OR (DNA) OR (metagenomic) OR (microarray)), following the PRISMA protocol. The review specifically targets healthcare environments with elevated concentrations of pathogenic bacteria. A total of 487 articles were initially identified, but only 13 met the inclusion criteria and were included in the review. The study disclosed that the prevalent molecular methodology for appraising aerosol quality encompassed the utilization of the PCR method, incorporating either 16S rRNA (bacteria) or 18S rRNA (fungi) amplification techniques. Notably, five diverse molecular techniques, specifically PFGE, DGGE, SBT, LAMP, and DNA hybridization methods, were implemented in five distinct studies. These molecular tests exhibited superior capabilities compared to traditional bacterial and fungal cultures, providing precise strain identification. Additionally, the molecular methods allowed the detection of gene sequences associated with antibiotic resistance. In conclusion, molecular testing offers significant advantages over classical microbiological culture, providing more comprehensive information.

Relationship in development of malocclusions to polymorphisms of selected vitamin D receptors.

BACKGROUND: The development of malocclusion is related to various factor, many of which are still not fully explained. The steroid hormone, 1,25-dihydroxyvitamin D3, has pleiotropic effects. It plays a key role in skeletal metabolism and the control of cell repair by attaching to the nuclear vitamin D steroid receptor (VDR). This vitamin affects bone turnover through the processes of bone tissue formation and resorption via its action on cells of the osteoblastic and osteoclastic lineage, exerts a modulating effect on the immune system, and is involved in the regulation of cell proliferation and differentiation. The role of vitamin D3 (VD3) and its receptor polymorphisms is a rarely studied topic in dentistry. Due to the proven influence on bone turnover processes and immune responses, the main research topic is its relation to periodontal diseases, but so far, its role in the formation and development of malocclusions has not been assessed. OBJECTIVES: This study aimed to assess the association of selected VDR polymorphisms: Cdx2 (rs11658820), TaqI (rs7975232), BsmI (rs1544410), ApaI (rs7975232), and FokI (rs2228570) with the development of malocclusions. MATERIAL AND METHODS: A prospective observational study was performed. The examination consisted of a medical interview, intraand extraoral orthodontic diagnosis, alginate impression, cone beam computed tomography (CBCT), and venous blood sample to obtain genomic DNA and assess VDR polymorphisms. RESULTS: The rs11658820 polymorphism causes an almost 4-fold increase in the probability of the presence of a malocclusion. GT and TT genotypes of rs7975232 are also associated with a similar risk - almost 6 and almost 5 times higher, respectively. In turn, the effect of the rs2228570-AG and GG genotype polymorphisms on the occurrence of transversal anomalies was demonstrated (odds ratio (OR) = 8.46 and OR = 6.92, respectively). CONCLUSIONS: The association of individual polymorphisms with specific malocclusions should be carefully assessed, especially since some trends have been indicated.

Analysis of aerosol generation during Er:YAG laser-assisted caries treatment: A randomized clinical trial.

BACKGROUND: Maintaining biosafety in dental practice involves the effective elimination of aerosols produced during dental treatment. OBJECTIVES: To assess the quantity of aerosols and aerobic bacteria in the air during the treatment of caries. MATERIAL AND METHODS: The study involved 60 patients with a total of 60 molar teeth (n = 60) in the mandible who were divided into 2 groups based on caries treatment method. Group 1 (G1, n = 30) received treatment with a conventional dental turbine (W&H Synea TA-98LC; W&H, Burmoos, Austria), while group 2 (G2, n = 30) underwent treatment with an Er:YAG (erbium-doped yttrium aluminium garnet) laser (LightWalker, Fotona, Slovenia). Measurements of aerosol particles between 0.3 Em and 10.0 Em near the operatorfs mouth were taken using the PC200 laser particle counter (Trotec GmbH, Schwerin, Germany). The number of aerobic bacteria in the air was determined using 60 Petri plates with a microbiological medium (Columbia agar with 5% sheep blood) and the sedimentation method. A control group (G3) was established to measure initial aerosol levels and initial total number of bacteria colony-forming units (CFUs) before each treatment. RESULTS: In G1 (dental turbine), the median value of aerosol particles was 57,021 (42,564.67,568), while in G2 (Er:YAG laser), it was significantly lower at 33,318 (28,463.35,484) (p < 0.001). The median total bacteria count per cubic meter of air in G1 (conventional dental turbine + high volume evacuator (HVE)), G2 (Er:YAG laser + HVE) and G3 (control group before caries treatment) were 734 (420.988), 158 (96.288) and 48 (32.74), respectively, with a statistically significant difference between the groups (p < 0.001). CONCLUSIONS: The use of Er:YAG laser during caries treatment resulted in a 41.6% reduction in aerosol amounts and a 78.5% decrease in the total bacterial count (TBC) compared to treatment with a dental turbine.

Allogenic Bone Graft in Dentistry: A Review of Current Trends and Developments.

In an effort to prepare non-autologous bone graft or biomaterial that would possess characteristics comparable to autologous bone, many different allogenic bone derivatives have been created. Although different existing processing methods aim to achieve the very same results, the specific parameters applied during different stages material preparation can result in significant differences in the material's mechanical and biological properties The properties, including osteoconductive, osteoinductive, and even osteogenic potential, can differ vastly depending on particular preparation and storage techniques used. Osteogenic properties, which have long been thought to be characteristic to autogenic bone grafts only, now seem to also be achievable in allogenic materials due to the possibility to seed the host's stem cells on a graft before its implantation. In this article, we aim to review the available literature on allogenic bone and its derivatives as well as the influence of different preparation methods on its performance.

The Impact of Hydrogen Peroxide (H2O2) Fumigation on Bacterial Levels in Dental Office Environments: A Randomized Clinical Trial Investigation.

BACKGROUND: Fumigation with hydrogen peroxide has proven to be a highly effective approach to maintaining biological safety within dental offices. The main purpose of this research was to investigate the efficacy of hydrogen peroxide (H2O2) fumigation in reducing bacterial levels in dental office environments. METHODS: The study involved 30 participants diagnosed with moderate caries decay (ICDAS 3 and 4) in their mandibular molars. Sixty Petri dishes (two per patient) with Columbia Agar and 5% Sheep Blood were opened at the beginning of the caries treatment. After the completion of caries treatment and tooth restoration, 30 plates (G1 group) were closed. Following this, a 20 min fumigation procedure with 6% hydrogen peroxide biosanitizer using a compressed air device was conducted. After the fumigation, the remaining plates were closed (G2 group). The total number of bacteria CFUs (colony-forming units) in the dental office air was determined using the Koch sedimentation method. RESULTS: The total bacterial colony (TBC) level, measured in cfu/m3, demonstrated a significant decrease in the number of bacteria following room environment fumigation (163.1 ± 145.7; G2 group) compared to non-fumigated samples (817.2 ± 208.2; G1 group) (p < 0.001). The predominant bacteria observed in the microbiological plates before fumigation were Micrococcus and Bacillus species, found in 80% (24/30) and 60% (18/30) of the plates, respectively. Application of H2O2 room fumigation resulted in a significant reduction in bacterial numbers: 79.2% (5/30) for Micrococcus species (p < 0.001), 83.3% (3/30) for Bacillus species (p < 0.001), and 100% (0/30) for Staphylococcus arlettae (p < 0.05). CONCLUSION: Fumigation with 6% H2O2 is an effective method for reducing bacterial counts in a dental office environment.

Evaluation of photobiomodulation for postoperative discomfort following laser-assisted vital pulp therapy in immature teeth: A preliminary retrospective study.

BACKGROUND: Minimally invasive endodontics is recommended for young, immature teeth to preserve healthy pulp and dentin tissue. OBJECTIVES: The aim of the study was to examine the cold sensitivity of immature teeth that received photobiomodulation (PBM) after vital pulp therapy (VPT). MATERIAL AND METHODS: The study followed the STROBE guidelines and included 123 healthy patients aged 8-13. The immature teeth (incisors, premolars and molars) that qualified for VPT received the bioceramic material - Biodentine. In this experiment, teeth were treated immediately and at 24 h post-VPT with a 635-nm diode laser using a power of 100 mW, a power density of 200 mW/cm2 and a total energy of 4 J (PBM group, n = 43), while those not treated were the control group (n = 43). The tooth sensitivity to cold was measured using a visual analogue scale (VAS) before and at 6 h, 1 day, 7, 30, and 90 days after treatment. The predictor variable was PBM skills regarding the ability to decrease cold sensitivity after VPT. The primary endpoint was the time to reverse hypersensitivity to cold, and the secondary endpoint was the occurrence of possible side effects. The Mann-Whitney U test, Friedman test along with Dunn's post hoc test, and the χ2 test were used to investigate tooth sensitivity. RESULTS: Eighty-six immature permanent teeth of 86 children were included in the study. It was shown that the difference was significant for sensitivity to a cold stimulus between the groups at 6 h, 24 h, 7 days, and 30 days, but no difference was found preoperatively and at 90 days (6 h, 24 h, 7 days, and 30 days, p < 0.001, and 90 days, p = 0.079). However, patients in both groups reported a decrease in discomfort provoked by cold stimuli throughout the follow-up period. CONCLUSIONS: Photobiomodulation decreased postoperative sensitivity and was more acceptable for patients. Further randomized clinical studies with placebo-controlled groups are needed.

Mercury Content in Impacted Wisdom Teeth from Patients of the Legnica-Glogów Copper Area-An In Vitro Pilot Study.

The aim of this study was to determine the content of mercury in impacted third molars from Legnica-Glogów Copper Area residents to emphasize the effects of environmental pollution on the human body. A group of 72 patients with an average age of 27.3 ± 6.9 years participated in the study. Within this study, the research group (Legnica-Glogów Copper Area residents) comprised 51 individuals, while the control group (residents of Wroclaw) consisted of 21 participants. A higher number of female individuals participated in the research (55). The amount of mercury present in the samples was determined through atomic absorption spectrometry with the use of a SpectraAA atomic absorption spectrometer and a V2 AA240FS flame attachment that utilized an air-acetylene flame. The accumulation of Hg in the teeth of members of the control group residing in Wroclaw was studied, with a focus on identifying the risk factors that contribute to this phenomenon. The final model analyzed the presence of various factors, including thyroid and parathyroid gland diseases, cardiac diseases, and interval-scale Vit. D3 concentration. Among these factors, the presence of cardiac diseases was deemed statistically significant in relation to an increase in Hg concentration in third molars (rate ratio = 2.27, p < 0.0001). The concentration of mercury increased with the age and time of residence in the L-G Copper District.

Quantitative Evaluation of Aerosols Produced in the Dental Office during Caries Treatment: A Randomized Clinical Trial.

BACKGROUND: Effective removal of aerosols generated during dental treatment is crucial for maintaining biosafety in dental practice. This study aimed to measure the aerosol amount and the number of aerobic bacteria in the air during caries treatment. METHODS: The study involved 50 molar teeth (n = 50) in the mandible in 50 patients divided into two groups based on the type of a high-volume evacuator (HVE); G1 (n = 25) conventional HVE (EM19 EVO, Monoart® Euronda, Vicenza, Italy) and G2 (n = 25) a new, wider, customized HVE. The PC200 laser particle counter (Trotec GmbH, Schwerin, Germany) was used to measure aerosol particles in a range of 0.3-10.0 µm near the operator's mouth. The study used 60 microbiological plates with a microbiological medium (Columbia Agar with 5% Sheep Blood) to check the number of aerobic bacteria in the air. RESULTS: The mean value of aerosol particles in the G1 group (conventional HVE) was 54,145 ± 7915, while in the G2 group (test, wider evacuator) was lower and amounted to 32,632 ± 1803. (p < 0.001). The median total bacteria count in the air per cubic meter in control, G1 (HVE), and G2 (NEW-HVE) groups were 50 [36-60]; 772 [643-881]; 120 [92-139], respectively. (p < 0.05). Gram-positive cocci were the predominant bacteria in the plates: Micrococcus sp. (50%), Bacillus species (36.4%), Staphylococcus epidermidis (3.8%), Staphylococcus saprophyticus (3.8%). CONCLUSIONS: the application of the wider high-volume evacuator increases the air purity during caries treatment as well as the biological safety of a dental office.

Soft-Tissue Augmentation around Dental Implants with a Connective Tissue Graft (CTG) and Xenogeneic Collagen Matrix (CMX)-5-Year Follow-Up.

Proper horizontal and vertical thickness of the gingival connective tissue has been proven to be one of the success criteria in dental implant and reconstructive surgery. When thin tissue is found, gingiva augmentation methods can be used to increase the quality and volume of the tissue. Many methods have been described, among them pedicle soft-tissue flaps or autogenic tissue grafts. As an alternative to patients' own tissue, xenogenic materials can be used for grafting. The fundamental issue is to choose a material that will ensure the maximum therapeutic effect, while also minimizing the negative influence on the patient's health. The aim of this study was to compare gingival augmentation procedures using a palatal connective tissue graft (CTG) and an xenogenic soft-tissue substitute, Geistlich Mucograft (xenogeneic collagen matrix; CMX), and assess whether the timing of the graft surgery influences the clinical outcomes. The original study was a randomized control trial with a total of 75 implants placed. The patients received the soft-tissue thickening 3 months before the implant placement or 3 months after the implant placement (depending on the group). A connective tissue graft (CTG) or Geistlich Mucograft were used (depending on the group). For both the CTG and Geistlich Mucograft, better clinical outcomes were observed for maintaining the alveolar bone level and the thickness of the attached gingiva compared to the control group with no gingival augmentation. The Geistlich Mucograft showed good clinical performance in comparison to the control. Soft-tissue augmentation with the CTG before the implant placement was found to be most efficient method in terms of a stable increase of the tissue thickness since, throughout the entire observation period, the greatest increase of 1.035 mm (SD = 0.73 mm) in thickness was observed. Statistically important differences in the tissue thickness baseline compared after 5 years were observed for groups G1 vs. G2b (no augmentation vs. CTG before), G1 vs. G3b (no augmentation vs. CTG after) and for groups G2b vs. G3a (CTG before vs. CMX after).

An Experimental Anodized and Low-Pressure Oxygen Plasma-Treated Titanium Dental Implant Surface-Preliminary Report.

Chemical composition and physical parameters of the implant surface, such as roughness, regulate the cellular response leading to implant bone osseointegration. Possible implant surface modifications include anodization or the plasma electrolytic oxidation (PEO) treatment process that produces a thick and dense oxide coating superior to normal anodic oxidation. Experimental modifications with Plasma Electrolytic Oxidation (PEO) titanium and titanium alloy Ti6Al4V plates and PEO additionally treated with low-pressure oxygen plasma (PEO-S) were used in this study to evaluate their physical and chemical properties. Cytotoxicity of experimental titanium samples as well as cell adhesion to their surface were assessed using normal human dermal fibroblasts (NHDF) or L929 cell line. Moreover, the surface roughness, fractal dimension analysis, and texture analysis were calculated. Samples after surface treatment have substantially improved properties compared to the reference SLA (sandblasted and acid-etched) surface. The surface roughness (Sa) was 0.59-2.38 µm, and none of the tested surfaces had cytotoxic effect on NHDF and L929 cell lines. A greater cell growth of NHDF was observed on the tested PEO and PEO-S samples compared to reference SLA sample titanium.

An Experimental Anodized Titanium Surface for Transgingival Dental Implant Elements-Preliminary Report.

The characteristics such as microtopography, physical and chemical properties influence the behavior of an implant in a soft tissue. Anodization-as a potent method of titanium alloy surface modification-of the transgingival abutment or healing screw, has achieved some improvement. One of the possible surface treatment method is low-pressure radiofrequency oxygen plasma treatment. The aim of the study was to evaluate the chemical properties and cytocompatibility of the experimental surface. Titanium discs made of grade-23 titanium alloy (Ti-6Al-4V) anodized (A sample) with different voltage parameters (28, 67, 78, and 98 V) were included in the study. Half of the samples regarded as the "S" group were additionally treated with low-pressure radiofrequency oxygen plasma treatment. The surfaces were characterized using scanning electron microscopy, X-ray spectroscopy and Raman spectroscopy, and electrochemically investigated via a corrosion test. Furthermore, two cell lines were used, including the CHO-compatible reference line and a primary human fibroblast line for the MTT assay; direct (contact) cytotoxicity of the materials was tested with the cells, and the growth of fibroblasts on the surfaces of the different materials was tested. The morphology of the "S"-treated samples did not differ from the morphology of only-anodized samples. However, the oxygen concentration on the surface in that group slightly increased by about 1% as a result of post-trial treatment. The highest corrosion resistance was observed for both A-78 V and S-78 V samples. The cytotoxicity assay revealed no changes in cell morphology or vitality. The MTT test proved comparable culture viability among all groups; however, the "S" samples showed statistically significantly higher fibroblast proliferation and adhesion scores compared to the "A" samples. Through the in vitro study, the low-pressure radiofrequency oxygen plasma treatment of the anodized Ti-6Al-4V alloy presented itself as an auspicious option in the field of transgingival element surface modification of implants.

Laterally Positioned Flap Procedure with Augmented or Nonaugmented Palatal Connective Tissue Grafts in the Treatment of Multiple Adjacent Gingival Recessions: A Two-Year Follow-Up Study.

The most commonly used technique for covering gingival recessions is the coronally advanced flap (CAF) technique due to its high success rate. In clinical situations where there is less keratinized tissue apical to the defect due to unfavorable anatomical conditions, a more advantageous technique for this situation should be considered, specifically the laterally positioned flap (LPF). The aim of this study was to compare the gingival thickness after gingival recession coverage using the laterally positioned flap supported by an augmented and non-augmented connective tissue graft (CTG). Thirty-four patients with 105 gingival recessions of Miller's class I and/or II were enrolled in this study. The method of choice was the laterally positioned flap. The test group was treated with previously augmented CTG harvested from the palatal mucosa while the control group was treated with a non-augmented CTG. Clinical measurements were recorded at baseline, 6, 12 and 24 months after intervention. Clinical results showed a statistically more significant percentage of average and complete gingival recession coverage in the test group. The LPF in combination with an augmented CTG proves to be an effective alternative to the CAF. Greater improvement in gingival thickness was observed in the LPF with augmented CTG than in non-augmented CTG.

Comparison of the Effectiveness of the Ultrasonic Method and Cone-Beam Computed Tomography Combined with Intraoral Scanning and Prosthetic-Driven Implant Planning Method in Determining the Gingival Phenotype in the Healthy Periodontium.

The aim of this study was to compare the effectiveness of two diagnostic methods: ultrasonic gingival thickness measurement (UGTM) and cone-beam computed tomography, intraoral scanning by computer-aided design technology with prosthetic-driven implant planning software (CBCT/CAD/PDIP) in determining the gingival phenotype (GP). Thirty periodontally healthy patients were examined. The ultrasonic device Pirop G® with a frequency of 20 MHz and CBCT/CAD/PDIP were used to measure gingival thickness at upper canines and incisors in three points localized midbuccally, namely free gingival thickness (FGT), supracrestal (SGT) and crestal (CGT). Probing depth (PD), clinical attachment level (CAL) and width of keratinized tissue (WKT) were measured using periodontal probe. Intra-examiner and inter-examiner agreement and agreement between methods were evaluated using Bland-Altman analyses. Comparing both methods in the determination of SGT (bias = 0.17 mm, SD = 0.25 mm, p < 0.000) and CGT (bias = -0.45 mm, SD = 0.32 mm, p < 0.000) 95.0% and 95.6% agreement were found, respectively, and in the FGT range only 93.3% (bias = -0.45 mm, SD = 0.32 mm, p < 0.000). The presence of positive correlations between WKT and SGT was shown. A positive correlation between SGT and WKT confirms the purpose of measuring these parameters for the evaluation of the GP. Both the ultrasonic method and cone-beam computed tomography combined with intraoral scanning and prosthetic-driven implant planning method were useful in determining gingival phenotype, however, the ultrasonic method was more accurate for measuring GT.

Fractal Dimension and Texture Analysis in the Assessment of Experimental Laser-Induced Periodic Surface Structures (LIPSS) Dental Implant Surface-In Vitro Study Preliminary Report.

Laser-induced periodic surface structures (LIPSS) are the sub-wavelength periodic nanostructures generated by the femtosecond laser. Implant topography and its nanostructural changes can be important for biomedical applications. In order to compare the surface topography of different implants, appropriate mathematical and physical descriptive methods should be provided. The aim of the study was to evaluate the experimental LIPSS-based-Low Spatial Frequency LIPSS (LSFL) dental implant surfaces. Novel methods of surface analysis, such as Fractal Dimension Analysis and Texture Analysis, were compared to the standard surface roughness evaluation. Secondary, cell viability, and attachment tests were applied in order to evaluate the biological properties of the new titanium surface and to compare their correlation with the physical properties of the new surfaces. A Normal Human Dermal Fibroblast (NHDF) cytotoxicity test did not show an impact on the vitality of the cells. Our study has shown that the laser LIPSS implant surface modifications significantly improved the cell adhesion to the tested surfaces. We observed a strong correlation of adhesion and the growth of cells on the tested surface, with an increase in implant surface roughness with the best results for the moderately rough (2 µm) surfaces. Texture and fractal dimension analyses are promising methods to evaluate dental implants with complex geometry.

Oral cancer awareness among patients at 3 university hospitals in Poland and Germany: A survey research.

BACKGROUND: The epidemic of cancer (including oral cancer) is a growing public health and economic problem in the European societies. A high percentage of patients who come for the appropriate treatment are in the late stages of advancement, often with nodal and/or distant metastases. The literature on the public oral cancer awareness in Poland and Germany is limited. OBJECTIVES: To investigate the levels of public awareness about the early symptoms and risk factors of oral cancer, and to analyze the findings in the context of the socioeconomic profiles of the subjects. MATERIAL AND METHODS: The survey consisted of a 20-item questionnaire divided into 4 sections: socioeconomic and demographic factors, the awareness of oral cancer, symptoms of oral cancer, and its risk factors. It was distributed to 465 adult patients in Poland (Wroclaw and Lódz) and Germany (Dresden). RESULTS: The response rate was 97.6%. Most of the respondents (65.4%) had heard of oral cancer. The sources of information were mainly the traditional mass media and the Internet, with only 23.8% of the respondents indicating doctors as a source of information about oral cancer. What is worrying, only about 1/5 of the participants in each of the 3 centers had an oral cancer examination last year. The awareness of oral cancer correlated positively with the age of the respondents and negatively with the size of the place of residence. Education level had no significant impact on declared knowledge. CONCLUSIONS: The results of this survey do not only show unsatisfactory levels of patients' awareness of the risk factors and symptoms of oral cancer but also emphasize the need to improve the level of healthcare concerning this disease, including screening programs.

Short (6 mm) and Regular Dental Implants in the Posterior Maxilla-7-Years Follow-up Study.

Short 6 mm dental implants are considered as an alternative to the maxillary sinus elevation and bone augmentation procedure where there is a reduced alveolar ridge height. The aim of this study was to compare the implant survival rate between short dental implants (6 mm) and regular length implants (11-13 mm) when placed in combination with bone grafting and loaded with a single non splinted crown, seven years after placing the implant. It was conducted as a controlled clinical study of 30 patients with partial edentulism in the posterior maxilla. The protocol included radiological and clinical evaluation of the C/I ratio (length of the superstructure divided by the length of the implant crestal part), marginal bone level (MBL), ultrasonography measurement of soft tissue surrounding implant (STT), patient-reported outcomes, and biological and technical complications. A total number of 28 implants (93%) remained integrated during follow-up period. MBL of 0.50 and 0.52 mm was observed for short implants and regular implants, respectively. MBL was checked for correlation with STT, and a negative correlation was found between MBL: STT. Our study has demonstrated a significantly lower implant survival rate for short implants compared to regular implants (87% compared to 100%). Despite the loss of several implants, good clinical results were achieved in the remaining implants in both groups. It is, therefore, worth considering short implants as an alternative to regular implants with a sinus lift surgery.

Standardization of the ultrasound examination of the masseter muscle with size-independent calculation of records.

BACKGROUND: As ultrasonography provides objective parameters and values, it is a reliable method of examining the structure and dimensions of the masseter muscle. Although the method is well known, there is no standardization in clinical examination and data analysis yet. OBJECTIVES: The study aimed to measure masseter muscle thickness in designated areas to establish the most repeatable and clinically applicable method of ultrasound examination, and to assess differences in measurements in designated areas for clinical purposes by devising the size-independent parameter. The size-independent parameter may potentially be more clinically applicable than distance records, which are affected by the size of the subject. MATERIAL AND METHODS: An ultrasound examination of 124 masseter muscles was performed. Axial examination in 3 horizontal regions (lower, middle and upper) and coronal examination in 2 vertical regions (proximal and distal) was carried out. Masseter muscle thickness was measured in every designated area when relaxed (muscle at rest (RMT)) and with clenched teeth (contracted muscle (CMT)). A morphological independent functional index of thickness difference (FITD) was calculated. RESULTS: The study revealed very high statistical differences between RMT and CMT (p < 0.0001) in all designated areas but with location variations. Masseter muscle thickness significantly differed depending on the examined area and transducer projection. CONCLUSIONS: The ultrasound study showed that masseter muscle thickness significantly differs depending on the examined area. The authors emphasize the necessity to examine the masseter muscle in specified areas with both coronal and axial projections to achieve objective and repeatable examination. Notable clinical value is assigned to FITD, which is independent from the morphological dimensions of the muscle.

Influence of botulinum toxin A on craniofacial morphology after injection into the right masseter muscle of dystrophin deficient (mdx-) mice.

BACKGROUND: Severe craniofacial and dental abnormalities, typical for patients with progressive Duchenne muscular dystrophy (DMD), are an exellcent demonstration of Melvin L. Moss "functional matrix theory", highlighting the influence of muscle tissue on craniofacial growth and morphology. However, the currently best approved animal model for investigation of this interplay is the mdx-mouse, which offers only a limited time window for research, due to the ability of muscle regeneration, in contrast to the human course of the disease. The aim of this study was to evaluate craniofacial morphology after BTX-A induced muscle paralysis in C57Bl- and mdx-mice, to prove the suitability of BTX-A intervention to inhibit muscle regeneration in mdx-mice and thus, mimicking the human course of the DMD disease. METHODS: Paralysis of the right masseter muscle was induced in 100 days old C57Bl- and mdx-mice by a single specific intramuscular BTX-A injection. Mice skulls were obtained at 21 days and 42 days after BTX-A injection and 3D radiological evaluation was performed in order to measure various craniofacial dimensions in the sagittal, transversal and vertical plane. Statstical analysis were performed using SigmaStat®Version 3.5. In case of normal distribution, unpaired t-test and otherwise the Mann-Whitney-U test was applied. A statistical significance was given in case of p ≤ 0.05. RESULTS: In contrast to C57Bl-mice, in mdx-mice, three weeks after BTX-A treatment a significant decrease of skull dimensions was noted in most of the measurements followed by a significant increase at the second investigation period. CONCLUSIONS: BTX-A can induce changes in craniofacial morphology and presumably partially inhibit muscle regeneration in mdx-mice, but cannot completely intensify craniofacial effects elicited by dystrophy. Further research is necessary in order to fully understand muscle-bone interplay after BTX-A injection into dystrophic muscles.

Prevalence of hypodontia and supernumerary teeth in a German cleft lip with/without palate population.

BACKGROUND: The distribution of dental abnormalities among cleft patients concerning cleft type frequently poses ambiguity wherefore the aim of this study was to evaluate the prevalence of hypodontia and supernumerary teeth in an exemplary German cleft population dependent on the cleft type. METHODS: Radiographs and dental records of cleft patients, which had been treated and followed up in the Department of Oral and Maxillofacial Surgery, University Hospital Carl Gustav Carus Campus, Dresden, Germany (investigation period of 22 years) were evaluated concerning hypodontia and supernumerary teeth dependent on the cleft type. Out of 386 records, 108 patients met the inclusion criteria: non-syndromic cleft of the alveolus with or without palate (CL/P), at least one clear panoramic x-ray, sufficient dental records. Statistical analysis was performed using x-square and binominal test (p ≤ 0.05). RESULTS: Hypodontia was more frequent (54/50%) than supernumerary teeth (36/33.3%) and was more common in bilateral clefts of the lip and palate (BCLP) (70.1%) than in unilateral clefts of the lip and palate (UCLP) (51.6%) or clefts of the lip and alveolus (CLA) (34.5%) (p << 0.001). There was an average of 0.9 missing teeth per patient, thereof the upper lateral incisor was most often affected (23.2%). In contrast, supernumerary teeth were more frequent in CLA (51.7%; p = 0.014) than UCLP (29.0%) and BCLP patients (17.6%). CONCLUSION: The prevalence for numerical dental anomalies was significantly different among the cleft types. Hypodontia significantly increased with the extend of the cleft, whereas the prevalence of supernumerary teeth decreased.

Analysis of alveolar ridge width in an area of central lower incisor using cone-beam computed tomography in vivo.

BACKGROUND: Planning a comprehensive dental treatment should include assessment and classification of the condition of the alveolar ridge. Existing classifications are insufficient. This study aimed to investigate the frequency of bone deficiencies in the anterior mandible and to develop an extension of one of the alveolar bone dehiscence classification. METHODS: Cone-beam computed tomography scans of 100 adults with the mean age of 36.75 ±â€¯11.77 years were analyzed. Measurements were taken from the 31. tooth. RESULTS: The presence of any bone defect was found in 91 (91%) of cases. Fenestrations were detected in 9% of study images, and dehiscence were detected in 90% of study images. A thin alveolar plate of below 0.2 mm independent from the side was found in 37 (37%) of cases. The mean height of buccal fenestration was 3.10 ±â€¯1.09 mm, and the mean height of lingual fenestration was 2.73 ±â€¯0.91 mm. The mean height of buccal dehiscence was 4.39 ±â€¯1.82 mm, and the mean height of lingual dehiscence was 4.27 ±â€¯2.49 mm. CONCLUSIONS: An attempt to restore the correct morphology of the alveolar process after improper treatment constitutes a therapeutic challenge. The frequent occurrence of bone deficiency prompts establishing safe treatment planning strategies, including careful assessment of the alveolar process supported by the comprehensive classification of bone defects.