Maxillary Ones Research Articles

Prevalence and pattern of third molars impaction in a large Yemeni sample: a retrospective study.

The prevalence of teeth impaction varies substantially between different populations, and the impaction of third molars is the most commonly recorded. This study aimed to explore the prevalence and pattern of the third molars impactions among Yemeni population. This was a retrospective radiographic study conducted in Yemen between 2022 and 2023. The digital panoramic radiographs were collected from two major X-ray centers in Yemen. The angular position and depth of the impacted third molars were assessed according to the classifications of Winter and of Pell and Gregory, respectively. All radiographs were evaluated twice by one investigator in a two-week interval, and Kappa test was used for intra-rater reliability. Gender-wise differences, differences between both sides, and differences between maxilla and mandible were analyzed using Chi-squared tes with odds ratio (OR) for the risk of impaction. A P-value < 0.05 was considered significant. Panoramic radiographs of 6338 individuals were included. Their mean age was 35.1 ± 13.3 years andand 63.9% were females. A total of 25,352 sites (quadrants) were screened for the presence of thirds molars. Among which, 14,003 third molars (55.3%) were present in one or more sites. There were 1440 individuals (23%) with a total of 2828 impacted third molars (20% of the existing third molars). Females were less likely to have third molar impaction (OR = 0.46, CI95% = 0.4-0.52). Impaction of the mandibular third molars was significantly more frequent than the maxillary ones (OR = 1.15, CI95% = 1.04-1.26; P = 0.005). Horizontal and mesioangular impactions were statistically more frequent in the lower molars compared to the upper ones (P < 0.001 each). Contrastingly, vertical (P = 0.015), distoangular, and other impactions (P < 0.001 each)were statistically more frequent in the maxilla. Levels A and B were more frequent in the lower third molars, while level C was predominating in the upper molars (P < 0.001 each). The prevalence of third molars impaction is more frequent in males and mandibular arch. The angulation and level of impaction seem to be more complicated in the maxillary arch.

Retrospective analysis of the effects of impacted third molar on hematologic patients undergoing hematopoietic stem cell transplantation

ObjectiveThis study aimed to investigate the incidence, treatment status, and impact position of impacted third molars (ITM) and their effects on patients undergoing hematopoietic stem cell transplantation (HSCT). MethodsA retrospective analysis was conducted on the medical records of 454 patients who underwent HSCT, out of which 188 patients had ITM. The presence of ITM and its association with transplant-related infections and complications were recorded and analyzed. ResultsPatients with ITM were significantly younger. The number of mandibular ITM was notably higher than maxillary ones, and the risk of pericoronitis in mandibular ITM was significantly higher than in maxillary ones. Out of 311 ITM in 188 patients, 25 were extracted before transplantation. The proportion of extraction and treatment for ITM with pericoronitis or caries was significantly higher than that for ITM without such problems. Moreover, patients with a history of pre-transplant pericoronitis had a significantly higher probability of developing tooth-related complications during transplantation, caused by pericoronitis in ITM compared to patients without a history of pericoronitis. ConclusionPre-transplant examination and treatment of ITM are essential, especially in cases with a history of pericoronitis. Oral intervention can significantly reduce the occurrence of tooth-related complications related to ITM during transplantation.

Waferless Orthognathic Surgery with Customized Osteosynthesis and Surgical Guides: A Prospective Study

The purpose of this paper was to describe and to evaluate the accuracy of a protocol that involves CAD/CAM-generated cutting guides and customized titanium plates for waferless orthognathic surgery. Twenty-one patients consecutively treated between January 2021 and January 2023 were included. The preoperative virtual surgical plan (VSP) was compared with the final position determined from the postoperative CT scan and STL files. An alignment algorithm was employed to adjust the skull position in areas unaffected by the surgery. Absolute and signed deviations were calculated across all three dimensions for each maxilla, mandible and chin landmark. The accuracy analysis revealed an overall deviation of 0.93 mm (95% confidence interval [95%CI]: 0.86 to 0.99), which was &lt; 2 mm for all assessed landmarks (p &lt; 0.05; one-sample t-test). The mandibular landmarks showed greater deviation than the maxillary ones (p &lt; 0.001; independent-samples t-test). Considering the deviations along the three axes, statistically significant differences were identified (p &lt; 0.001; one-way analysis of variance). The reported protocol provides evidence on the benefit of guided orthognathic surgery when performed using a defined VSP protocol, improving accuracy in the maxilla, mandible and chin position, considered both globally and as isolated variables.

Morphometric variations and nonmetric anatomical traits or anomalies of the primary molar teeth, plus the molars' size thresholds for sex identification

IntroductionMorphological and morphometric features of the teeth are of interest to various clinical and academic dental and medical fields including prosthodontics, orthodontics, anatomy and anthropology, pathology, archeology, and forensic dentistry. These have been more or less researched in the case of the permanent dentition. However when it comes to the primary dentition, the literature is scarce and controversial. No study worldwide exists on the cutoff points (thresholds) for sex identification; no study exists on metric or nonmetric traits of deciduous teeth in Iranians. Hence, the aim of the study was to assess both the metric and nonmetric traits of primary molars, as well as their cut-off points for sex identification.MethodsIn this epidemiological cross-sectional study, pretreatment casts of 110 children (51 boys and 59 girls) aged 6 to 12 years were collected. Maxillary and mandibular first and second primary molars were evaluated regarding their metric traits (mesiodistal and buccolingual widths) and 9 nonmetric traits (Accessory cusp on the upper D, Accessory cusp on the lower D, Fifth cusp on the upper E, Carabelli’s cusp on the upper E, Protostylid on the lower E, Fifth cusp on the lower E, Sixth cusp on the lower E, Tuberculum intermedium [metaconulid] on the lower E, and Deflecting wrinkle on the lower E). ROC curves were used to identify cut-off points for sex determination as well as the usefulness of metric measurements for this purpose. Data were analyzed using independent-samples and paired-samples t-tests, McNemar, Fisher, and chi-square tests, plus Pearson and Spearman correlation coefficients (α = 0.05).ResultsAll the primary molars’ coronal dimensions (both mesiodistal and buccolingual) were extremely useful for sex identification (ROC curves, all P values ≤ 0.0000099). Especially, the mandibular primary molars (areas under ROC curves [AUCs] between 85.6 and 90.4%, P values ≤ 0.0000006) were more useful than the maxillary ones (AUCs between 80.4 and 83.1%, P values ≤ 0. 0000099). In the mandible, the first primary molar (maximum AUC = 90.4%) was better than the second molar (maximum AUC = 86.0%). The optimum thresholds for sex determination were reported. Sex dimorphism was significant in buccolingual and mesiodistal crown widths of all the primary molars (all P values ≤ 0.000132), but it was seen only in the case of 2 nonmetric traits: Deflecting wrinkle (P = 0.001) and Tuberculum intermedium (metaconulid, P = 0.029) on the lower Es, taking into account the unilateral and bilateral cases. The occurrence of nonmetric traits was symmetrical between the right and left sides (all P values ≥ 0.250). All mesiodistal and two buccolingual molar measurements were as well symmetrical (P > 0.1); however, two buccolingual measurements were asymmetrical: in the case of the maxillary E (P = 0.0002) and mandibular D (P = 0.019). There were three weak-to-moderate correlations between the nonmetric traits of the mandibular second molars (Spearman correlations between 22.7 and 37.5%, P values ≤ 0.045). Up to 6 concurrent nonmetric traits were observed in the sample, with 53.6% of the sample showing at least 2 concurrent nonmetric traits at the same time, without any sex dimorphism (P = 0.658).ConclusionSex dimorphism exists considerably in primary molars’ sizes, but it is not as prevalent in their nonmetric traits or abnormalities. Primary molars’ crown sizes are useful for sex identification; we calculated optimum cut-off points for this purpose, for the first time.

Investigation of the causes and pattern of early first permanent molar extraction in children in the western Mediterranean region of Türkiye

Aim: This study aims to investigate the causes and pattern of extraction of first permanent molars (FPMs) in children aged 6-15 years in the western Mediterranean region of Türkiye. Methods: The data from the patients who applied to Department of Pediatric Dentistry, Faculty of Dentistry, Akdeniz University, between the years 2016–2020, were scanned; patients, who had at least one FPM extracted between the ages of 6–15, and who had pre-extraction panoramic radiographs were selected. Information about age, gender, reason for extraction, extracted tooth, and previous treatment status of a total of 562 patients (263 males and 299 females) were recorded. The data were statistically analyzed using chi-square tests. Results: The mean age was 11.87±1.89, and there was no difference between female and male patients (p=0.828). 727 FPMs were evaluated, and the main reason for extraction was detected to be “Excessive substance loss” (55.8%) for both genders in all age groups. The 2nd, 3rd, 4th, and 5th reasons were early FPM extraction, infection, parents’ request, and others respectively. The total number of extracted teeth of female patients was higher (53.6%) than that of males (46.4%) but there was no significant difference. It was observed that mandibular teeth were more frequently extracted than maxillary ones. Most children (75.8%) had one tooth extracted, 19.9% had two teeth, and 3.3% had three teeth. It was determined that the FPMs were not previously treated in the majority of children (90.7%). Conclusions: The most important finding from this study is that most of the extracted FPMs have not been treated previously. This indicates that individuals in our society do not have enough information about and are late in accessing oral health services. Therefore, further steps should be taken to improve public oral health. Keywords: Child; First Permanent Molar; Tooth Extraction

Evaluation of Clinical Periodontal Parameters of Abutment Teeth Supporting Distal-Extension Base Removable Partial Dentures: A Cross-sectional Study.

To assess the clinical periodontal status of abutment teeth in regards of different design components of distal-extension removable partial dentures. Subjects (N=100) with acrylic or cobalt-chromium distal-extension removable partial dentures were enrolled and their periodontal parameters plaque and gingival indices [PI, GI], probing depths [PD], clinical attachment loss [CAL] and a mobility index [MI] evaluated. Denture base type, major connector, occlusal rests position, design of direct retainers, retention, stability and denture wearing habits were further evaluated. Acrylic RPDs were associated with higher mean±SE PI [1.70±0.74], GI [1.76±0.55], PD scores [2.47±1.02 mm] and CAL values [4.46±2.11 mm] compared to CO-CR RPDs [p⟨0.05]. For abutments, the PI [1.6±0.83], GI [1.72±0.57], PD [2.32±1.03] and CAL [4.26±2.08] were higher than their non-abutments counterparts [p⟨0.05]. CAL scores were found to be significantly higher for mandibular abutments compared to maxillary ones [P=0.002]. The highest PI [1.83±1.10] and GI [2.00±0.00] scores were associated with lingual bars and horse-shoe connectors, respectively. Full palatal coverage and lingual plates were associated with the highest PD [2.80±0.48] and CAL [4.70±0.37] scores. Acrylic RPDs, type of major connector, wrought wire clasps and distal occlusal rests may be considered as risk factors for periodontal disease progression in distal-extension removable partial denture wearers.

Alveolar bone changes following bi-maxillary vertical molars’ movements using clear aligners

ObjectiveThis study aimed to assess the alveolar bone changes following maxillary and mandibular molars’ intrusion and extrusion movements using Clear Aligners using Cone-Beam Computed Tomography (CBCT).Materials and methodsThis is a retrospective clinical study in which 24 adult patients with pre-designed selection criteria and a mean age of 31.1 + 9.9 years were enrolled. The alveolar bone changes around one hundred thirty-three maxillary and mandibular molars intruded or extruded by Clear Aligners therapy were analyzed from CBCT using Invivo 6.0 software. Intra- and inter-examiner reliability analysis was performed using the intra-class correlation coefficient (ICC) and Cronbach’s Alpha statistics. The paired t-test was used to analyze significant differences before and after treatment (T0-T1). The significance level was considered at P < 0.05.ResultThe patients were divided into two groups: extrusion (48.9%, n = 65 molars’ root) and intrusion (51.1%, n = 68 molars’ root) group. There was a significant decrease in the alveolar bone changes in the buccal surface of the mandibular right and left 1st molars in the extrusion group (-1.05 ± 0.97, -0.76 ± 1.12 mm, respectively) and the maxillary left 2nd molars in intrusion group (-0.42 ± 0.77 mm), and the lingual surface of intrusion of the mandibular left 1st molar (-0.64 ± 0.76 mm). Comparing the mean maxillary and mandibular changes (T0-T1) of both studied groups showed that the buccal alveolar bone changes for the left 1st and right 2nd molars showed a significant difference in extrusion and intrusion groups, respectively.ConclusionsThe buccal alveolar bone changes is considered the most affected surface following maxillary and mandibular molars’ intrusion and extrusion movements using clear aligners, with mandibular molars being more affected than the maxillary ones.

Avoiding the lockdown: Morphological facilitation of transversal chewing movements in mammals.

The evolution of mammals is characterized, amongst other developments, by an increasing relevance of effective food processing in form of an increasingly durable dentition, complex occlusal surfaces, and transverse chewing movements. Some factors have received increasing attention for the facilitation of the latter, such as the configuration of the jaw joint, the chewing muscle arrangement and lever arms, or the reduction of interlocking cusps on the cheek teeth occlusal surface. By contrast, the constraining effect of the anterior dentition (incisors and canines) on transverse chewing motions, though known, has received less comprehensive attention. Here, we give examples of this constraint in extant mammals and outline a variety of morphological solutions to this constraint, including a reduction of the anterior dentition, special arrangements of canines and incisors, the nesting of the mandibular cheek teeth within the maxillary ones, and the use of different jaw positions for different dental functions (cropping vs. grinding). We suggest that hypselodont anterior canines or incisors in some taxa might represent a compensatory mechanism for self-induced wear during a grinding chewing motion. We propose that the diversity in anterior dentition among mammalian herbivores, and the evolutionary trend towards a reduction of the anterior dentition in many taxa, indicates that the constraining effect of the anterior dentition, which is rigidly linked to the cheek teeth by the osseous jaws, represents a relevant selective pressure in mammalian evolution.

Diet-related dental wear in archaeological human populations of Chalcolithic and Bronze Age from North-Eastern Romania.

Dental macrowear is the non-pathological loss of hard tissues on the occlusal surface of the teeth. In archaeological contexts, the loss of tooth tissues is often correlated with lifestyles, habits, and with the physical properties of the consumed food - including preparation techniques. We report the first semiquantitative and quantitative assessment on dentine exposure of permanent second molars (M2) using the scale scoring technique, image analysis, and regression analysis on human teeth from Chalcolithic and Bronze Age archaeological populations discovered in North-Eastern Romania. We show an increase of dentine exposure percent (PDE) with the age-ranges, but no evidence of wear by sex were observed. In the linear regression analysis, the age and the dentine exposure percent, as variables, were correlated in 31% of the mandibular M2 molars and 49% in the maxillary ones (p < 0.001). Moreover, the multiple regression analysis involving the dentine exposure and the three variables that could influence the dental wear (i.e., age, occlusal area, and period) revealed no differences in dental wear between Chalcolithic and Bronze Age, as well as between different cultures of Bronze Age (i.e., Monteoru Culture and Noua Culture). Therefore, apart from age, occlusal area, and period, there may be other factors including diet and food-processing techniques that could be also considered when discussing the loss of tooth tissues in archaeological populations, especially farmers.

Orthodontic Treatment and Central Incisors: a Study by CBCT Analysis

To determine potential risks and critical orthodontic movements of central incisors. CBCT analysis of 66 patients (aged 12-38 years; 30 adolescents and 36 adults; 33 males and 33 females). We evaluated alveolar bones (crests, plates, ridges) surrounding central incisors from buccal and lingual sides, and at multiple levels using the "Ez3D-plus" program with regard to buccolingual inclination and effective length of premaxilla/length of the mental protuberance. We identified: - Potential risks in the maxilla, in case of 1) Proclined central incisors, on the first buccal coronal third and lingual side of alveolar bone. 2) ELP < 13 mm, with buccal movement. - Potential risks in mandible, in case of 1) Retroclined central incisors, on the first lingual coronal third and buccal apical two-thirds of alveolar bone. 2) LMP > 9 mm. - Critical orthodontic movements: 1) Buccal tipping of mandibular central incisors is more critical in adolescents. 2) Lingual tipping of mandibular central incisors is more critical than of maxillary ones in all groups, at the level of the alveolar crest. In adult males, at the first lingual coronal third of the alveolar plate. In adult females, at the buccal apical level. 3) Movement towards cortical bone: In all groups, buccal movements of maxillary central incisors are more critical than of mandibular ones, and lingual movements of mandibular central incisors are more critical than of maxillary ones, especially in adult males. We recommend an accurate diagnosis of incisors position and alveolar bone status, and planning of orthodontic treatment at an earlier age.

Prevalence and pattern of dental caries in primary molars among Libyan school children in Benghazi

Aims: To assess prevalence and severity of dental caries in primary teeth among Libyan school children in Benghazi. Study design: Cross sectional observational study. Material and Methods: A total of 236 school children, aged 8-9 years were selected for a dental examination. The oral health was measured using World Health Organization (WHO) diagnostic criteria for dental caries: decayed, missing and filled tooth, dmft index for primary dentition. Results: The overall caries prevalence was 83.5% (mean dmft 3.3) with the highest caries prevalence recorded among 8 year-old children (45.3%, mean dmft 3.53). Mean decayed, missing and filled teeth (dmft) was 2.91, 0.31, 0.09 respectively. Second primary molars had higher dmft than the first (mean dmft 1.72, 1.33 respectively) and the difference was statistically significant p=0.001. The mean dmft of mandibular primary molars was higher than that of maxillary ones (mean dmft 1.67, 1.38) and the differences was statistically significant p=0.01. Conclusion: While the prevalence of dental caries in primary teeth was found to be high, the treated and filled teeth are very low. The most commonly affected teeth were second primary molars, especially in the mandible. Dental caries occurred most often in the mandible. This study provided us with the baseline data for prevalence of dental caries. Providing oral health education and preventive programs would assist in improving the oral health condition of school children.

Effect of septal deviation on nasomaxillary shape: A geometric morphometric study.

Nasal cavities in their primitive stage communicate with the oral cavity until the 8th week of intrauterine life where the posterior palate initiates its development. Hence, starting from the initial growth phases, a significant connection lays between the nasal structures and the maxillary bone and witnessing key functional roles, among which the respiration. Proper nasal breathing has been proven to be a crucial factor for the maturity of the craniofacial complex, and obstruction of the respiratory airway due to nasal septum deviation can generate clinically significant reduction of the nasal airflow. This situation will imply irreversible repercussions that hinders the harmonious development of the craniofacial complex. In order to understand such potential impacts of septal deviation, our first objective was to materialize the relation between septum deviation, and both nasal cavity and maxillary structures. For the second objective, we used Procrustes analysis to assess the shape variation of these two anatomical regions, the bivariate plots of Principal Components to evaluate their shape space, and a two-block Partial Least Square (PLS) to explore their covariation. We analysed, in this cross-sectional study, 62 posteroanterior cephalometric radiographs of adult subjects from both sexes (23males, 39 females; mean age 25.3years) collected from the database of the Department of Orthodontics at Lebanese University. Landmarks were plotted and variables were calculated and divided into nasal septum, nasal cavity and maxillary ones. The sample was further divided into two groups based on septal deviation severity (a septal deviation is considered minor if <6). The results suggested that nasal septum deviation was correlated to reduced nasal cavity area and a reduced maxillary area. Moreover, the comparison of the two groups concluded that the difference between all variables was statistically significant with higher scores in the minor septal deviation group. These findings were corroborated with the shape analysis where the mean centroid size of nasal cavity and that of the maxilla in the group of reduced septal deviation were significantly greater than those of the group with increased angle of deviation. Results of PLS analysis concluded to a strong covariation between nasal septum and nasomaxillary complex. These conclusions support the early septoplasty in growing patients as a solution to redirect the normal course of growth and re-establish a good function of the nasomaxillary complex.

Craniofacial Growth in Adolescence and its Influence on the Mandibular Incisor Crowding.

BackgroundTo analyze craniofacial growth during adolescence from the ages of 12 to 21 years and its relation to late mandibular incisor crowding.Material and MethodsThe study included 61 orthodontically untreated subjects (49% males). Lateral cephalograms were used to assess the jaw growth and inclination of the incisors. Little’s Irregularity Index and the anterior mandibular dental arch depth of mandibular dentition were measured.ResultsA reduction of the skeletal class angle (ANB) was observed in both genders, although it was significant only in males (η2=0.188; p=0.015). The growth of the mandible was more prominent compared to that of the maxilla, and it was more prominent in males than in females. The skeletal vertical dimension, however, demonstrated a significant reduction in both genders (η2=0.527-0.593, p<0.001). The mandibular incisors tended to retrocline in both genders, while the maxillary ones tended to procline in males, and slightly retrocline in females. A decrease in the mandibular dental arch depth occurred in both genders (η2=0.259; p<0.05). An increase in the irregularity of incisors for 1.8±1.7 mm on average (95% CI 1.3-2.2; η2=0.520; p<0.001) was observed in both genders. A logistic regression revealed that less sagittal growth of maxilla (increase of SNA angle ≤2°) and reduction of convexity in skeletal sagittal interjaw relationship (reduction of ANB ≥1°) were significant predictors of the occurrence of crowding (Δ Little Irregularity Index ≥1mm) yielding odds ratios of 4.9 and 4.8.ConclusionsThe differential growth of the maxilla and mandible is related to the occurrence of late crowding, mostly in smaller amounts in maxillary sagittal growth compared to the mandible.

Age and Sequence of Permanent Teeth Eruption in Lebanese Children.

Background The timing of eruption of permanent teeth can be a precious help to the pediatric practitioner in identifying an appropriate treatment plan. Usually, it presents a more precise sign of an early or late growth of the child. Aims It is to determine whether the timing of the permanent teeth eruption in Lebanese pediatric population can be considered as standard Lebanese values, since no other study was previously performed. Materials and Methods A cross-sectional study is conducted, and the clinical emergence data are collected for a sample of 2317 Lebanese children aged between 5.5 years and 13 years (1129 girls and 1188 boys) from different socioeconomic groups in rural and urban communities spread over different regions in Lebanon. The study investigates dental emergence patterns. Results Statistical analysis is performed with the SPSS Software. A confidence interval of 95% and significance level of 5% are adopted. The trend is for males to begin their permanent teeth eruption later than girls. Emergence of all permanent mandibular teeth is earlier than maxillary ones. Symmetry is found between the right and left teeth in the maxilla, as well as in the mandibula. Conclusion In this study, the results indicate that premolars and second permanent molars erupt earlier in the Lebanese children compared to children of other countries reflected in several studies.

Maxillary Ameloblastoma: A Review With Clinical, Histological and Prognostic Data of a Rare Tumor.

Diagnosis of odontogenic tumors can be challenging due to their rarity and diverse morphology, but when arising near the tooth, the diagnosis could be suspected. When their location is not typical, like inside the paranasal sinuses, the diagnosis is less easy. Maxillary ameloblastomas are exceedingly rare with only sparse information on their epidemiological, histological and genetic characteristics. The aim of this report is to thoroughly review the available literature in order to present the characteristics of this tumor. According to available data, maxillary ameloblastomas can occur in all ages but later than mandible ones, and everywhere within the maxillary region without necessarily having direct contact with the teeth. No sex preference has been shown. The most common histological patterns seen in this location are the follicular and plexiform ones. Maxillary ameloblastomas are locally aggressive neoplasms, thus therapy aims for excision including normal bone beyond the lesion. In contrast to mandible ameloblastomas, maxillary ones most commonly show mutations of the SMO gene. Furthermore, differential tumor diagnosis is thoroughly discussed in the present review.

A multi-centre evaluation of 566 cases of ameloblastoma in Nigeria by the African Oral Pathology Research Consortium

Ameloblastoma is a locally aggressive odontogenic tumour (OT) that arises from odontogenic epithelium without neoplastic involvement of odontogenic ectomesenchyme. It is the commonest OT in developing countries, especially in Africa, and, hence, a clinically significant lesion among Africans. It has been suggested that the biologic behaviour of ameloblastoma in black Africans is different from the other populations. The high incidence of ameloblastoma in Africans warrants further evidence-based research. In this descriptive cross-sectional study, AOPRC employed a multi-centre approach to retrieve archival demographic and clinicopathological data on ameloblastoma from five major tertiary health institutions in South–West and South–South regions of Nigeria. Data were generated using a standardized data extraction format and analysed using Epi-info (version 7.0). From the five centres, a total of 566 cases met our study criteria. We observed that there was a slight male preponderance on ameloblastoma among the cases studies. For all types of ameloblastoma, mandibular lesions were found more frequently than maxillary ones. Most patients presented within 1–5 years of onset of jaw swelling (45.94%). There was a statistically significant higher mean duration for unicystic variants as compared to multi-cystic ameloblastoma (p = 0.0215). Overall, we also observed that the plexiform variants were the most frequently occurring and that the acanthomatous variant was significantly more common in females than males (p = 0.01). The current study serves as primer and justification for the application of emerging novel molecular techniques to understand the pathobiology and basis for clinic-pathological disparity of ameloblastoma among men of African descent.

Evaluation of permanent first molar tooth loss in young population from North Turkey

Background/Aim: Rate of missing permanent teeth in a population is important for oral health indicators. The aim of this retrospective study was to evaluate the prevalence of previously missing permanent first molar (PMF) teeth in a young population. Material and Methods: 1204 healthy patients who received panoramic radiographs were selected randomly at their first visiting to Samsun Ondokuz Mayis University Faculty of Dentistry. The patients' age ranges were 7 to 17. Information about extracted permanent first molar teeth, missing regions, patients' ages, and genders was recorded. The data were statistically analyzed using chi-square tests. Results: 1,204 patients, of these, 608 (51%) were female, and 596 (49%) were male. 4,816 PFM teeth were evaluated in this study, and 128 of them (2.66%) had extracted from 97 different patients. There were statistically differences between groups in terms of age and gender (p&lt;0.05). It was observed that mandibular teeth were more frequently extracted than maxillary ones, and lower left permanent first molar teeth had more extracted than the others. Conclusions: The first permanent molar teeth could be extracted different reasons. However, these teeth should be protected by both dentists and patients.

Clinical and radiographic outcomes of three different loading protocols for single-implant-supported prostheses: A randomized controlled trial

Aims: The aim of this study is to assess the effects of early, immediate, and progressive loading of dental implants clinically and radiographically. Materials and Methods: Twenty implants were inserted in 20 patients. Five implants were used for each group (early, immediate, progressive, and conventional loading). In early loading, implant was loaded after 1 week. In immediate loading, loaded with temporary crown within 48 hours then definitive prosthesis after 4 months. In progressive loading loaded with temporary crowns out of occlusion after 3 months for the mandibular sites and 4 months for the maxillary ones for 1 month, and then loading on centric occlusion for 1 month, then full occlusion for 2 months, then definitive prostheses were used. Radiographic assessment for crestal bone loss was done. Clinical assessment of periodontal pocket depth was performed at 3, 6, and 9 months. Results: At 9 months, probing depths were 1.80 ± 0.37, 2.10 ± 0.34, 2.25 ± 0.18, and 1.83 ± 0.38, for immediate, early, progressive, and control groups, respectively. Immediate group showed statistically nonsignificant bone loss after 3 months in the mesial side but showed statistically significant bone loss after 6 and 9 months whereas statistically significant bone loss through all periods in the distal side. Early group showed statistically significant bone lose. Progressive group showed statistically nonsignificant bone loss after 3 months but significant loss after 6 and 9 months. Control group showed statistically nonsignificant bone loss. Conclusions: Immediate loading showed excellent soft-tissue reaction, and early loading responses are identical to conventional two-staged procedure. Progressive loading demonstrated significantly less crestal bone loss than conventional one.

Standards for permanent tooth emergence in Czech children

BackgroundThe aim of this study is to develop a population-specific reference for permanent tooth emergence among 4–15 years old Czech Republic children. The reference derived from this sample population are essential for pediatric dental diagnostics, orthodontic treatment planning, as well as anthropological and forensic applications.MethodsIn this cross-sectional epidemiological survey, dental examinations of 1,370 Czech children (696 girls (50,8%) and 674 boys (49,2%), whose parents or legal guardians all signed informed consent forms) from 11 elementary schools and kindergartens were performed in the classroom. During the examination, previously emerged permanent teeth (other than third molars), the child's age and gender were recorded. A tooth is defined as having erupted when at least any part of the crown penetrates the gingiva, and is clinically seen in the oral cavity. A logistic regression model was used to calculate the median emergence age per tooth for both genders and the total sample. The data was statistically processed (using IBM SPSS Statistics 23) and carried out at a deviation level of 0.05. The statistical significance of the differences in the emergence of permanent teeth (contralateral, intermaxillary, inter-gender differences) was evaluated by the McNemar test.ResultsNo statistically significant differences were observed in the emergence times between right and left sides. In addition, mandibular teeth emerged earlier than the corresponding maxillary ones (with the exception of the first and second premolars). Permanent teeth were found to emerge sooner in girls. Furthermore, the greatest inter-gender difference was observed in maxillary canines.ConclusionsThe new data reported can now be used as standards when assessing permanent tooth emergence of Czech children.

Adhesion of mutans streptococci to self-ligating ceramic brackets: in vivo quantitative analysis with real-time polymerase chain reaction.

To analyze in vivo mutans streptococci (MS) adhesion to self-ligating ceramic brackets [Clarity-SL (CSL) and Clippy-C (CC)] and the relationships between bacterial adhesion and oral hygiene indices. Four central incisor brackets from the maxilla and mandible were collected from 40 patients (20 patients per each bracket type) at debonding immediately after plaque and gingival indices were measured. Adhesions of Streptococcus mutans, S. sobrinus, and total bacteria were quantitatively determined using real-time polymerase chain reaction after genomic DNA was extracted. Factorial analysis of variance was used to analyze bacterial adhesion to the brackets with respect to the bracket type and jaw position. Correlation coefficients were calculated to determine the relationships of bacterial adhesion to oral hygiene indices. Adhesion of total bacteria and S. mutans to CSL was higher than that to CC (P < 0.001). Adhesion of total bacteria to the mandibular brackets was higher than that to the maxillary ones (P < 0.001), while adhesion of S. mutans to the maxillary brackets were higher than that in the mandibular ones (P < 0.001). In particular, the proportion of S. mutans to total bacteria in CSL was higher than CC (P < 0.05) in the maxillary anterior teeth (P < 0.001). There were no significant differences in adhesion of S. sobrinus between the brackets and jaw positions. Interestingly, no significant relationships were found between bacterial adhesions and oral hygiene indices. Complex bracket configurations may significantly influence bacterial adhesion to orthodontic brackets. Further in vivo study using bracket raw materials will help to define the relationships between bacteria adhesion and enamel demineralization. Because oral hygiene indices were not significantly correlated with adhesions of MS to self-ligating ceramic brackets, careful examinations around the brackets should be needed to prevent enamel demineralization, regardless of oral hygiene status.