OBJECTIVE: To analyze the differences in cusp height on radiographs, establishing proportional relationships between cusp and alveolar bone crest (ABC) measurements. The goal of this study was to develop a correction coefficient by considering this proportion.
METHODS: Twenty-one artificial teeth, molars and premolars, and bovine ribs were used. Interproximal radiographs were taken with the aid of a positioner. The vertical angles used were: 0°, + 5°, and + 10°, and processed using three spatial resolutions measured in line pairs per mm (lp/mm): 20, 25 and 40. The Perio filter was applied to each image, in addition to the original one. Combinations of angle, resolution, and filter were made. Eighteen images were analyzed by three specialists, resulting in 252 measurements for each evaluator, totaling 756 measurements.
RESULTS: The overall variability of the measurements can be explained mainly by the variation in tooth anatomy. The 0° 25 lp/mm Perio filter method was the closest one to the actual clinical scenario for both cusps and ABC. The correction factor managed to explain 71.45% of the errors.
CONCLUSIONS: The variation in vertical angulation interferes with cusp and ABC measurements, and the angulation at 0º and spatial resolution of 25 lp/mm showed better results. The use of correction coefficients allowed approaching actual measurement values.
CONCLUSIONS: More accurate ABC height measurements are essential even in radiographic exams that do not meet the standard of excellence because the need to repeat radiographic exams is then eliminated.

The primary step in forensic odontological analysis is sex determination. The present study is one of the few studies that evaluated the accuracy of the combination of canine tooth root length and crown measurements for sex determination. The study sample comprised 196 cone-be am computed tomographic scans of individuals aged 20-80 years distributed in five age categories: 20-29, 30-39, 40-49, 50-59, and 60+ years old. Different parameters, such as width, length, and ratio measurements for the crown and root of each maxillary and mandibular canine tooth, were examined and recorded. The findings indicated that maxillary canines had greater sex dimorphism ability (87.3%) than mandibular canines (80.6%). Total tooth length and root length of maxillary canine were the most pronounced variables in the differentiation of sex groups. When the combination of the mandibular and maxillary measurements was considered, the accuracy for sex dimorphism was 85.7%. By using ratio variables, the accuracy was reduced to 68.9%. According to the findings of this study, total tooth length and root length are the most discriminant variables of canine teeth. These variables are more reliable sex indicators than crown measurements.

BACKGROUND: It is now possible to predictably distalize maxillary first molars in nongrowing patients with the infra-zygomatic gear distalizer and to improve malocclusions without having to extract the premolars and regardless of the patient\'s compliance. The purpose of this study was to investigate the amount and rate of distal movement of the maxillary first molars using our proposed appliance after extraction of maxillary second molars.
METHODS: Ten nongrowing female patients successfully treated with our proposed appliance were the subjects of this study. The amount, rate, and type of distalization, were analyzed through upper jaw cone beam computed tomography (pre- and post-treatment) and scanned casts taken on a monthly interval.
RESULTS: The average amount of distalization of the maxillary first molars was 4.03 mm at the crown level and 2.88 mm at the root level. The rate of distalization had an average of 0.61 mm per month with a maximum of 0.79 mm in the first month because of the regional acceleratory phenomena after extracting the maxillary second molar.
CONCLUSIONS: The maxillary first molars were distalized in a significant manner and all patients reached a Class I relation within an average duration of 6.4 months. The proposed appliance proved to be a viable noncompliance modality to distalize maxillary first molars correcting maxillary Class II malocclusions characterized by maxillary protrusion or maxillary incisor crowding.

BACKGROUND: Supracrestal gingival tissue dimensions (SGTDs) has been considered to be an essential element of periodontal phenotype (PP) components. This study aimed to explore the relationship between SGTDs and other PP components by digital superposition method that integrated cone beam computed tomography (CBCT) with intraoral scanning.
METHODS: This cross-sectional study was conducted at the Stomatology Hospital of Fujian Medical University. Participants were recruited based on the inclusion and exclusion criteria. The data obtained from the digital scanner (TRIOS 3, 3Shape, Denmark) and CBCT images were imported into the TRIOS software (Implant Studio, 3Shape, Denmark) for computing relevant parameters. The significant level was set at 0.05.
RESULTS: A total of 83 participants with 498 maxillary anterior teeth were finally included. The mean values of supracrestal gingival height (SGH) and the distance from the cementoenamel junction (CEJ) to the crest of the alveolar ridge (CEJ-ABC) on the buccal site were significantly higher than palatal SGH (SGH-p) and palatal CEJ-ABC (CEJ-ABC-p). Men exhibited taller CEJ-ABC and SGH-p than women. Additionally, tooth type was significantly associated with the SGH, SGH-p and CEJ-ABC-p. Taller SGH was associated with wider crown, smaller papilla height (PH), flatter gingival margin, thicker bone thickness (BT) and gingival thickness (GT) at CEJ, the alveolar bone crest (ABC), and 2 mm apical to the ABC. Smaller SGH-p displayed thicker BT and GT at CEJ, the ABC, and 2 and 4 mm apical to the ABC. Higher CEJ-ABC showed lower interproximal bone height, smaller PH, flatter gingival margin, thinner GT and BT at CEJ, and 2 mm apical to the ABC. Smaller CEJ-ABC-p displayed thicker BT at CEJ and 2 and 4 mm apical to the ABC. On the buccal, thicker GT was correlated with thicker BT at 2 and 4 mm below the ABC.
CONCLUSIONS: SGTDs exhibited a correlation with other PP components, especially crown shape, gingival margin and interdental PH. The relationship between SGTDs and gingival and bone phenotypes depended on the apico-coronal level evaluated.
BACKGROUND: This study was approved by the Biomedical Research Ethics Committee of Stomatology Hospital of Fujian Medical University (approval no. 2023-24).

BACKGROUND: When conducting a forensic investigation, one of the most important steps is establishing the biological profile of a victim who cannot be positively recognized or is just a skeleton. It has been shown that, among the other clinical indicators, the diameters of dental crowns are a good and dependable source for determining gender in a particular population sample. However, the literature is sparse regarding their assessment as a viable marker for the determination of a particular race. In addition, the need for population-specific data has also been advocated while determining gender dimorphism based on tooth size.
OBJECTIVE: To study the bisexual variation in the permanent dentition of individuals from three different sets of populations: Arabian, South Asian, and East Asian. The other objective is to explore the role of this odontometric analysis in predicting the racial identity of the subjects belonging to the aforementioned population.
METHODS: The research was conducted at the College of Dentistry, AlJouf University in Sakaka. Measurements of mesiodistal and buccolingual (BL) distances were taken using a digital vernier caliper on a total of 75 pairs of research models or casts. Statistical tests were run on the information gathered.
RESULTS: Of the 75 casts, 38 (50.7%) were of male and 37 (49.3%) were of female. Our analysis showed between genders, a significant difference in maxillary central incisor (P = 0.001), first premolar (P = 0.01), and first molar (P = 0.02) while for a mandibular arch, a significant difference was noted for incisors (P = 0.002) with greater tooth dimension in male than in the female. Concerning the BL dimensions, only the mandibular canine showed a significant difference between males and females (P = 0.001). Comparisons of the crown dimensions between population groups showed that the Arabian population consistently exhibits larger tooth dimensions than the other two populations in both arches.
CONCLUSIONS: A few crown dimensions can be used as an adjunctive tool for the identification of the gender and race of an individual.

We used fluorochrome labeling to study spatiotemporal variation of dentin apposition (DAR) and extension (DER) rates during crown and root formation of mandibular first molars from wild boar and domestic pigs. DAR was reconstructed along the course of dentinal tubules in four zones of the crown and in the upper root area. In all five zones, mean DAR increased during the first 30% to 40% of apposition, reaching highest values (22-23 μm/day) in the upper-lateral crown zone. Lowest values were recorded near the dentin-pulp interface (DPI). Typically, DARs in contemporaneously formed dentin areas were higher in more cuspally compared to more cervically/apically located zones. DER was high (>200 μm/day) in early postnatal crown dentin and then decreased markedly in cervical direction, with lowest values in the cervical crown zone. After this nadir, DER sharply increased in the upper 30% to 40% of the root extension, reaching values equaling (wild boar) or even surpassing (domestic pigs) those recorded in the upper lateral crown. After this peak, DER again decreased. While DAR did not differ markedly between wild boar and domestic pigs, the DER showed marked differences, both regarding maximum values (208.1 μm/day in wild boar, 272.2 μm/day in domestic pigs) and the timing of the root growth spurt, which occurred earlier in the domestic pigs. We consider the more rapid recruitment of secretory odontoblasts in domestic pigs (reflected by higher DER) a side effect of selection for rapid body growth during pig domestication.

BACKGROUND: Crown fracture is the most common injury in permanent teeth. This study aimed to evaluate the treatment outcomes of permanent teeth with uncomplicated and complicated crown fractures and to investigate potential factors.
METHODS: This retrospective study included patients who experienced crown fractures in permanent teeth from 2018 to 2021 with at least 12 months of follow-up. All complicated crown fractured teeth were treated with pulpotomy, while for teeth with uncomplicated crown fractures, three treatments (restoration, indirect pulp capping, or pulpotomy) were employed. The chi-square test was used to compare the prognosis of teeth with uncomplicated and complicated crown fractures. Potential factors associated with pulp survival including gender, interval, root development, enamel infraction, mobility, concomitant luxation injury, treatment, and coronal restoration were identified via Cox regression analysis.
RESULTS: A total of 307 teeth from 220 children (average age = 9.3 ± 1.4 years; age range, 6-14 years) with a median follow-up of 23 months were included, and 82.1% of all teeth had immature roots. Complicated crown fractured teeth (93.6%, 102/109) had a significantly higher success rate compared with uncomplicated crown fractured teeth (85.4%, 169/198) (p < .05). Pulpotomy (96.9%) had the highest success rate of all treatments for uncomplicated crown fractures, followed by only restoration (85.0%) and indirect pulp capping (76.9%). The success rate of teeth that received pulpotomy was significantly higher than those treated by indirect pulp capping (p < .05). In uncomplicated crown fractures, teeth with Class II mobility were more vulnerable to failure than teeth without abnormal mobility (HR = 34.83; 95% CI, 9.59-126.56; p < .05); teeth that received pulpotomy were less prone to failure than teeth that received indirect pulp capping (HR = 13.53; 95% CI, 1.58-115.72; p < .05).
CONCLUSIONS: Crown fractures treated with conservative pulp treatments had a relatively highly favorable prognosis. The prognosis of uncomplicated crown fractured teeth was impacted by the severity of periodontal injury and treatment strategies. Accurate diagnosis and identification of micro-exposures are important. Dentists should take multiple risk factors into account and select optimal treatment strategies.

OBJECTIVE: To investigate the accuracy of the Invisalign appliance in achieving predicted angular tooth movement of the maxillary central incisors, to locate the center of rotation in a labio-palatal direction, and to investigate any difference between 1-weekly and 2-weekly wear protocols.
METHODS: This study involved a retrospective sample of two groups of 46 Class I adult subjects treated non-extraction with different protocols of 1-weekly and 2-weekly wear. The pretreatment, predicted outcome and achieved outcome digital models were superimposed and measured using metrology software. Angular and center-of-rotation measurements in the sagittal plane for the maxillary right central incisor were analyzed.
RESULTS: There was a statistically significant difference between predicted and achieved angular measurements (P < .005) for labial tooth movements regardless of wear protocol. For palatal movements, no statistically significant difference was observed (P > .05). A small amount of overexpression was observed in some cases. Regarding crown and root control, uncontrolled tipping was the most predictable. No statistically significant difference was found between predicted and achieved center of rotation, but the confidence interval was wide. No statistically significant difference (P > .05) was found between the two wear protocols for the parameters measured.
CONCLUSIONS: For maxillary central incisors, labial angular movements were not as accurate as palatal movements. Overcorrection could be recommended with careful clinical monitoring due to the possibility of overexpression. Control of root movements may be unpredictable, and further research is required to draw stronger conclusions. For the parameters measured in this clinical sample, there was no difference between the two wear protocols.

Even if survival of post and core (PC) itself was frequently investigated in recent literature, clinical data concerning the risk for extraction of teeth restored with PC is still scarce. Since most authors found the loss of retention of refitable post and cores as the most common cause of failure, it is impossible to draw a conclusion on tooth survival on the results of those studies. Therefore, the aim of the present study was to improve the clinical evidence on the survival of teeth treated with post and cores on a large number of cases over a long observation period.
735 patients were treated with 1053 post and cores in the observation period (2004-2022) and could be included in the study. The patient files were analysed due to the parameters: Type of covering prosthetic restoration, location, type of tooth, luting material, post and core material, bone attachment and therapist. The survival probability was assessed using Kaplan-Meyer analysis. Cox regression was used to assess possible multifactorial influences.
The overall average survival time until necessary extraction of a tooth restored with a post and core was 11.74 years. A root fracture in primary crown retained removeable partial dentures (RPDs) during the first five years was the most common reason for extraction in this study. A significant influence on the survival time of teeth restored with post and cores was found for the type of covering restoration, bone attachment, age of the patient and post and core material.
Post and core restored teeth should be avoided as abutments for primary crown retained RPDs.
If it is inevitable to utilise post and core restored teeth for primary crown retained RPDs, post and core materials with matching mechanical properties to that of dentine should be preferred.

OBJECTIVE: The recommended treatment for uncomplicated crown fractures is bonding the fractured fragment or the fragment reattachment. A paucity was identified regarding the studies comparing the efficacy of micro-hybrid and nanohybrid composites in fragment reattachment. Hence, the present study aimed to evaluate and compare three materials for bonding of fragments rehydrated by humidification in teeth with uncomplicated crown fractures.
METHODS: Eighty mandibular bovine incisors with similar dimensions and free of any structural deformities were fractured similar to the technique followed in previous studies. Fracture was simulated, fragments, and stumps were coded, stumps were stored in artificial saliva and the fragments were dehydrated at room temperature and pressure. They were randomly assigned to Group-1 (no rehydration), Group-2 (rehydrated and bonded by flowable nanohybrid composite-3M Filtek Supreme Syringe Flowable Composite Resin-A2, Sao Paulo, Brazil), Group-3 (rehydrated and bonded by flowable micro-hybrid composite- Ruby Flow, InciDental, England, United Kingdom), and Group-4 (rehydrated and bonded by light-cured Glass-Ionomer-Cement-Voco Ionoseal, Cuxhaven, Germany). The samples were subjected to a universal testing machine to evaluate the force required to fracture the bonded fragments.
RESULTS: The highest median value of the force required to fracture was recorded for Group 2 (208.4 N) followed by Group 3 (195.2). The force required to fracture the bonded fragments was lowest in Group 4 (67.2 N) which was lower than the negative control (131.4 N). The differences between the observations in Groups 2 and 3 were not found to be statistically significant.
CONCLUSIONS: The nano and micro-hybrid composites showed greater force required to fracture than fragments bonded by LC-GIC. Dehydrated fragments bonded using nanocomposites performed better than rehydrated fragments bonded by using LC-GIC.