"Examining the link between tooth agenesis and papillary thyroid cancer: is there a risk factor?" Observational study.

BACKGROUND: Mutations in one or multiple genes can lead to hypodontia and its characteristic features. Numerous studies have shown a strong genetic influence on the occurrence of hypodontia, and identified several genes, including AXIN2, EDA, FGF3, FGFR2, FGFR10, WNT10A, MSX1, and PAX9, that are directly associated with dental agenesis and carcinogenesis. The objective of this study was to investigate the occurrence and pattern of tooth agenesis, microdontia, and palatally displaced canine (PDC) in women diagnosed with papillary thyroid cancer (PTC), compared to a control group of women without any malignancy or thyroid disease. MATERIALS AND METHODS: This case-control study was carried at the Department of Orthodontics, School of Dental Medicine University of Zagreb, and Department of Oncology and Nuclear Medicine Sestre Milosrdnice University Hospital Centre. The study involved a clinical examination and evaluation of dental status, panoramic X-ray analysis, and assessment of medical and family history of 116 female patients aged 20-40 with PTC, as well as 424 females in the control group who were of similar age. RESULTS: The prevalence of hypodontia, microdontia, and PDC was statistically higher in women with PTC than in the control group. The prevalence rate of hypodontia was 11.3% in the experimental group and 3.5% in the control group. The experimental group showed a higher occurrence of missing upper lateral incisors, lower left central incisors, and all the third molars (except the upper left) compared to the control group. Women with PTC showed the prevalence of PDC significantly higher than the control group (3.5%, 0.7%, p = 0.002). The probability of hypodontia as a clinical finding increases 2.6 times, and microdontia occurs 7.7 times more frequently in women with PTC. CONCLUSION: Our study suggests a possible link between odontogenesis and PTC. The absence of permanent teeth may increase the likelihood of PTC in women. Leveraging the age-7 orthopantomogram to identify women at high risk for PTC within a critical early detection window could significantly improve oral health outcomes and PTC prognosis through proactive interventions.

Hide and seek: Impacted maxillary and mandibular canines from the Roman period Croatia.

OBJECTIVE: The aim of this paper was to analyse the dental remains of an adult male with three impacted canines from the Roman period cemetery in Osijek, Croatia. MATERIALS: The dental remains of an adult male aged 35-45 years at the time of death were analysed. METHODS: Macroscopic analysis of dental remains was accompanied by radiographic examination. RESULTS: The individual also had additional dental pathologies (carious lesion, antemortem tooth loss). A total of 21 permanent teeth were present in maxillae and mandible. Eighteen of them were normal fully erupted dentition, while three were impacted: left maxillary canine and both mandibular canines. The left maxillary and mandibular canines were mesially inclined, and the right mandibular canine was relatively horizontally positioned. CONCLUSION: A case of non-syndrome impaction in which the lack of eruptive force in combination with the unfavorable position of the tooth bud might have resulted in multiple impacted teeth is presented. SIGNIFICANCE: Current clinical knowledge reports low frequency of this anomaly, with maxillary impaction occurring more often than mandibular. Furthermore, canine impaction is even more rarely reported in the archaeological material. The presented case is the only one from the archaeological setting with impaction present both in maxillae and mandible. LIMITATIONS: In modern populations multiple impactions are often associated with various syndromes. Since the majority of syndromes affect soft tissue, their association with impaction cannot be confirmed in archaeological populations.

Shear Bond Strength of Orthodontic Brackets Luted with RMGIC After Er:YAG Laser Etching with Two Pulse Modes Using a Digitally Controlled "X-Runner" Handpiece.

OBJECTIVE: To compare the shear bond strength (SBS) values of orthodontic brackets luted using a resin-modified glass ionomer cement (RMGIC) on enamel surfaces etched using either an Er:YAG laser in two different working modes, or a conventional etching protocol, including phosphoric acid. MATERIALS AND METHODS: Sixty healthy human premolars were randomly allocated to three experimental groups (n = 20) and etched with: Group 1: Er:YAG laser in super-short pulse (SSP) mode (100 mJ, 20 Hz, 2 W); Group 2: Er:YAG laser in quantum square pulse mode (120 mJ, 10 Hz, 1.2 W) using a digitally controlled handpiece ("X-Runner"); Group 3 (control): 5.25% sodium hypochlorite pretreatment, then 37% phosphoric acid for 15 sec. Stainless steel brackets were bonded using light-curing RMGIC for orthodontic bonding. After term cycling (1800 cycles), SBS testing was performed using a universal testing machine. After debonding, both enamel and bracket surfaces were examined to determine the amount of RMGIC still present on the surfaces. RESULTS: Group 3 surfaces gave the lowest mean SBS (10.6104 ± 2.66196 MPa), whereas Group 1 provided the highest 1 (13.1795 ± 3.37904 MPa), which was significantly different from the control (Group 3, p = 0.0226). Group 2 provided intermediate values (11.8486 ± 0.59832 MPa) nonsignificantly different from the control or from SSP (p = 0.4215 and p = 0.3082, respectively). CONCLUSIONS: Er:YAG laser treatment in SSP mode of enamel surfaces for orthodontic bonding provided higher SBS and a shear behavior of the luting material similar to the conventional acid-etching procedures, making it a viable alternative to acid etching.

Clinical and microbiological parameters in patients with self-ligating and conventional brackets during early phase of orthodontic treatment.

OBJECTIVE: To determine the effect of different bracket designs (conventional brackets and self-ligating brackets) on periodontal clinical parameters and periodontal pathogens in subgingival plaque. MATERIAL AND METHODS: The following inclusion criteria were used: requirement of orthodontic treatment plan starting with alignment and leveling, good general health, healthy periodontium, no antibiotic therapy in the previous 6 months before the beginning of the study, and no smoking. The study sample totaled 38 patients (13 male, 25 female; mean age, 14.6 ± 2.0 years). Patients were divided into two groups with random distribution of brackets. Recording of clinical parameters was done before the placement of the orthodontic appliance (T0) and at 6 weeks (T1), 12 weeks (T2), and 18 weeks (T3) after full bonding of orthodontic appliances. Periodontal pathogens of subgingival microflora were detected at T3 using a commercially available polymerase chain reaction test (micro-Dent test) that contains probes for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola. RESULTS: There was a statistically significant higher prevalence of A actinomycetemcomitans in patients with conventional brackets than in patients with self-ligating brackets, but there was no statistically significant difference for other putative periodontal pathogens. The two different types of brackets did not show statistically significant differences in periodontal clinical parameters. CONCLUSION: Bracket design does not seem to have a strong influence on periodontal clinical parameters and periodontal pathogens in subgingival plaque. The correlation between some periodontal pathogens and clinical periodontal parameters was weak.

Importance of interincisal index for predicting mesiodistal crown diameters of canines and premolars.

The aim of this study was to examine the accuracy of regression equation for prediction of the mesiodistal diameter (MDD) of the crowns of canines and premolars (C, P1, P2), and to determine whether an incisal indexs can serve as a reliable predictor. MDD and vestibulooral diameter (VOD) of the crowns of central and lateral incisors (I1, I2), C, both P1, and P2, and first permanent molars (M1) in both jaws were measured on the plaster casts of 150 subjects (75 boys and 75 girls). The obtained measurements were compared and correlated with predicted values (by linear regression equation derived previously), with respect to gender, jaw side and value of the interincisal index. The correlation coefficients between measurements and predicted MDD of the C, P1, and P2 were calculated with respect to gender and jaw. The values varied from 0.62 to 0.81. It could be concluded that normal values of the interincisal index of the I1 and I2 are highly associated with measured and predicted MDD of the C, P1, and P2 crowns. Correlation coefficients ranged from 0.84 to 0.99.

Proportions in the upper lip-lower lip-chin area of the lower face as determined by photogrammetric method.

This study is concentrated on the lower face profile, the emphasis being given to the lips and chin area which have been analysed by various proportions. A sample consisted of 110 subjects (52 males and 58 females) with good soft tissue profile, dental class I and Caucasian type. All the records were taken in the natural head position (NHP) and all measurements were performed using the computer and by the same operator. Using the photographs of the facial profile, seven vertical measurements were taken and seven indices used to determine the relationships between measurements of the lower third of the face, lower lip, chin and upper lip. Almost all the vertical profile measurements were greater in males than in females. The only variables with no gender differences were lower (Li-Sto) and upper vermilion heights (Ls-Sto). The largest portion of the lower face was occupied by the chin and the smallest by the lower lip height in both genders. All indices were greater in females except (IND7) representing chin/lower third of the face proportion, which was greater in males. Some acknowledged aesthetic guidelines must be followed when determining orthodontic plan for optimal aesthetics. The proportional relationships found in our sample are a valuable contribution and might serve as a template for vertical facial analysis of the lower face in this patient population.

Soft tissue profile typology: results of the cluster analysis.

The aim of the study was to establish a mathematical classification of normal soft tissue profile by cluster analysis based on linear and angular photogrammetric measurements.The sample consisted of 110 subjects, 52 males (mean age, 28.7 y) and 58 females (mean age, 25.7 y), with good and balanced soft tissue profile and dental class 1 occlusal relationship and were white. The measurements were made with standardized photographic records taken in natural head position.The 39 soft tissue variables (27 linear and 12 angular) were classified according to similarity by cluster analysis. Males and females were separated in an effort to identify representative values for each group. The squared Euclidean distance was used for distance measurement, and the Ward method was used for cluster analysis. Measurement variables for cluster analysis were standardized using z score. Four recognizable types of soft tissue profiles were obtained in both sexes, which differ mostly with regard to the position of the lips and prominence of the chin. This study found a highly significant sex dimorphism in the soft tissue profile, presenting that the form difference is both a size and a shape difference between male and female soft tissue profiles. The lower third of the face expressed most of the sex differences.

Correlation between the pattern of facial growth and the position of the mandibular third molar.

PURPOSE: The purpose of this study was to examine the correlation between variables that determine the position of the third molar (M3) and correlation between the pattern of facial growth and examined variables. MATERIALS AND METHODS: Material for the study consisted of 130 panoramic radiographs and lateral radiographs of subjects' heads in whom orthodontic therapy had been started. Analysis of the position of the mandibular M3 and its relation to the bone and other teeth were determined by 4 variables: evaluation of the space for both M3, spatial relation between the second molar and M3, vertical position of the M3 in relation to the alveolar ridge, and inclination of the germ of the M3. RESULTS: In boys, significant correlation was determined on the right side of the jaw, between the retromolar area and the vertical position of M3. Significant correlation was determined in girls, between the retromolar area and the vertical position of M3 on both sides, retromolar area and M3 inclination on the left side, and retromolar area and spatial relation of M3 on the right side. Analysis of correlation between facial growth pattern and 4 variables that determinate the position of M3 showed positive correlation only for the lower right M3 inclination in subjects with anterior facial rotation. CONCLUSION: The present study showed that the amount of retromolar space for the position of the M3 is not a sign of its normal development. No significant differences were determined between the position of M3 and type of facial growth.