Developmental and Acquired Abnormalities of the Teeth.

This review aims to present a detailed analysis of the most common developmental and acquired dental abnormalities, including caries, resorptive lesions, and congenital anomalies of teeth number, size, form, and structure. This review highlights how diagnostic imaging can aid in the accurate identification and management of these conditions.

Five-Year Clinical, Radiographic, and Cone-Beam Follow-Up of Socket Shield Technique in Two Cases Treated with a Split Mouth Design.

The two presented cases of socket shield technique were done following a split mouth protocol in two patients, each received an immediate implant inserted conventionally on maxillary one side and another implant inserted applying the socket shield technique on the contralateral side. The outcomes including soft and hard tissue changes were compared clinically and radiographically. The four implants were followed for 5 years, and the outcomes were successful.

A prospective case series in regenerative endodontics: The effective use of diluted antibiotic hydrogels in endodontic regeneration procedures.

Objective: to investigate the effectiveness of diluted antibiotic hydrogels in endodontic regeneration procedures. Materials and Methods: One conventional treatment (calcium hydroxide) and two experimental treatments containing 1 mg/mL antibiotic in gel (MC-TAP and MC-DAP) were prepared for this study. The effect of these medicaments on the proliferation and differentiation potential of dental pulp stem cells (DPSCs) was examined before their clinical use, using WST and ALP assays. Twenty-two teeth diagnosed with necrotic immature roots were treated with calcium hydroxide, MC-TAP or MC-DAP using the endodontic regeneration protocol as described by the American Association of Endodontists (AAE). Teeth were examined after application of the medicament, at the time of regeneration and after 12-24 months. Results: All treated teeth showed resolution of signs and symptoms shortly after treatment with the different medicaments. However, signs and symptoms returned a few months after initial treatment in clinical cases treated with MC-DAP. All successfully treated teeth examined after 12-24 months were free of signs and symptoms, but vitality was not achieved. Conclusion: Low concentration antibiotic gel containing triple antibiotic paste (MC-TAP) can be successfully used for endodontic regeneration procedures.

Dentists' knowledge and preference regarding gingival displacement methods.

INTRODUCTION: An accurate impression is an essential procedure for fabricating indirect fixed restorations. To achieve a precise final impression, the management of gingival tissue is without doubt a crucial. AIM: To evaluate the use of different gingival displacement techniques among dental clinicians and to assess their associated knowledge and technique preferences. METHODS: A self-designed survey was created electronically and sent to a list of dentists. The survey was composed of multiple sections. Participants who stated that they do not use GD methods were asked to answer the survey questions based on their knowledge. Descriptive statistics were generated, andChi-square test was used to examine the association between the different variables. RESULTS: A total of 188 dentists participated in this study. The majority 144 (76.6%) use GD in their practice. When asked which technique yields a more accurate impression with lower incidence of repeating the impression, 93 (64.6%) reported retraction cord technique with a hemostatic agent results in a higher impression accuracy, while only 14 (9.7%) declared the retraction paste technique as being more accurate. CONCLUSION: The cordless GD technique is believed to be easier, faster, and less traumatic to the gingival tissues, nevertheless, the outcome of dental impressions is believed to be more predictable with the use of conventional retraction cords and hemostatic medicaments.

Do upper third molars provide more accurate age estimation in the adult based on the pulp-to-tooth ratio than lower third molars? A cone-beam CT study.

INTRODUCTION: Age-at-death estimation is an essential part of the identification process of individuals in many forensic dentistry cases where identity of the individual cannot be resolved by visual recognition or other means. Dental age estimation in adults is more of a challenge as most teeth complete their development by the age of 18 years. AIM: This study aims at using the mesio-distal (MD) pulp-to-tooth ratio taken at the cervix of upper third molars (UM3) to estimate age at the time of radiographic imaging. MATERIALS AND METHODS: A set of 135 Cone-beam computed tomography (CBCT) radiographs of UM3s for a random sample of 135 Jordanian adults (65 females, 70 males; age range = 18-63 years, mean age = 34.4 years, SD = 11.2 years) were used. Both pulp and tooth MD diameters were measured at the cervix. MD pulp-to-tooth ratios for UM3s were correlated with age. RESULTS: Statistically significant negative moderate correlation was found between the age of the individual and the cervix MD pulp/tooth ratio (r = -0.516). This indicates that only 26.6% of the variation in age can be explained by the cervix MD pulp-to-tooth ratio. CONCLUSIONS: This study concludes that cervix MD pulp-to-tooth ratio of UM3s, although apparently stronger than that of lower M3s (r = -0.361), is not a sufficiently reliable estimator of age in adults, and this is perhaps attributed to the greater variability in the time line of third molars development.

Impact of COVID-19 pandemic on dental education: online experience and practice expectations among dental students at the University of Jordan.

BACKGROUND: The quarantine associated with the COVID-19 pandemic forced dental schools to suspend their clinical training and to shift to distant learning methods. The aim of this study is to investigate the impact of quarantine on the self-perceived preparedness of dental graduates and to explore the efficacy of online education from students' perspectives. METHODS: The questionnaire distributed to dental students comprised of two main sections. The first part covered the online education experience, and the second part measured the level of self-perceived preparedness for a range of cognitive, communication and professional skills. RESULTS: The survey yielded a response rate of 72%. The majority of students (77%) agreed that they missed educational experiences as a result of the lockdown. More than half of them felt less motivated to follow-up with distant e-learning and believed that online assessment is not a good method for evaluation. A high percentage of the students (66%) thought that online group discussions had a positive value while 67% preferred online lectures compared to theatre lectures. Majority of students particularly 5th year (78.7%) (p < 0.001) stated that the quarantine increased their collaboration with their colleagues. According to 87% of students, the experience most negatively affected was their clinical training. In general, students showed satisfactory self-perceived preparedness related to a range of attributes and professional skills. CONCLUSIONS: The data showed that students partially appreciated the online system, whereas they did not consider it a substitute for face to face clinical practice. The overall self-perceived preparedness level was promising; however students had reservations regarding independent practice following graduation.

Dental students' experience and perceived confidence level in different restorative procedures.

PURPOSE: Graduating confident students who are able to flourish and develop in their future careers is an importance outcome of the dental education. This study aims to evaluate self-perceived level of confidence of fifth-year dental students in different restorative-related tasks and the relationship between their clinical training and its corresponding confidence. METHODS: Fifth-year graduate dental students (n = 202) were asked to fill a questionnaire that rated their level of confidence in different clinical restorative dentistry tasks. Additionally, they were asked about the number of times they performed tasks prior to attempting the equivalent competency and in which sub-specialty they felt the most confident. RESULTS: Completed responses were received from 120 students giving a response rate of 59%. Students felt the most prepared and confident in direct restorations and simple endodontic treatment, and they seemed less confident in indirect restorations and complex endodontic treatment. Regarding the steps of indirect restorations, students expressed least confidence in crown preparation compared to impression making and try-in procedures (P < .05). Students rated their confidence highest in operative dentistry, followed by endodontics and lastly fixed prosthodontics. CONCLUSION: The results highlight the areas in which students exhibit the least confidence. Enhancement of student clinical skills and directed exposure is necessary to raise the level of perceived confidence which will reflect positively on their current and future professional performance.

Dentists' knowledge, attitudes, and professional behavior toward the COVID-19 pandemic: A multisite survey of dentists' perspectives.

BACKGROUND: COVID-19 continues to affect the dental community worldwide. The authors conducted a cross-sectional electronic study using a multisite survey to examine dentists' knowledge, attitudes, and professional behavior toward COVID-19 and the affect on their livelihood. METHODS: A questionnaire was circulated via e-mail and social media platforms to dentists in North America, Europe, Eastern Mediterranean, and Western Pacific regions. It covered demographic characteristics and questions about the COVID-19 outbreak related to dentists' levels of comfort for preventive and safety measures, provision of treatment, affect on work, and financial implications. Responses were tabulated and analyzed by means of χ2 or Fisher exact test. Mann-Whitney and Kruskal-Wallis tests were used to compare means. P < .05 was considered significant. RESULTS: A total of 1,251 dentists responded. General dentists represented 63.9% of the respondents and 62.5% worked in private practice. The global score for level of comfort with the preventive measures and provisions of treatment during the COVID-19 pandemic was low (14 of 30), and differences between regions were significant (P < .01); dentists working in private practice and general dental practitioners were less comfortable (P < .01). CONCLUSIONS AND PRACTICAL IMPLICATIONS: The respondents reported a lack of preparedness to confront a highly infectious respiratory disease. A new level of protective armamentarium in the dental operatory and updated operational guidance and policies are required, necessitating educators and regulators to ensure the delivery of knowledge and skills to oral health care providers. Dentists need to address the sustainability of their practices and have a robust business plan.

Dental Student Perspectives of a Comprehensive-Based Teaching Methodology: A Confidence, Effectiveness, and Challenge Report.

Background/Objectives. The holistic methodology in education has been widely appreciated and implicated in dental schools in the last decade. Our department of conservative dentistry decided to reform the educational model of teaching from a traditional requirement-based model to a hybrid model incorporating comprehensive care treatment. The aim of our study was to assess students' confidence and perspectives regarding the benefits of a comprehensive model of teaching. Materials and Methods. A questionnaire was distributed at the end of the academic year 2018-2019 and designed to investigate students' opinions on the benefits of the new model of teaching, as well as difficulties encountered and possible shortcomings. In addition, self-perceived confidence level was assessed for the purpose of comparing confidence during supervised tasks versus confidence during comprehensive patient care. Results. Complete responses were gathered from 127 students out of 202, giving a response rate of 63%. The majority of students believed that the comprehensive model of teaching allowed them to better address patients' needs, gave higher satisfaction, positively influenced self-confidence, permitted greater exposure to clinical techniques, and enhanced reasoning and analytical skills. However, their confidence was still lower in comprehensive patient management when compared to supervised tasks. Conclusion. Our students showed an appreciation of the comprehensive care model. Self-learning and didactic skills were enhanced. It would, therefore, be beneficial to adapt this methodology to earlier years and other disciplines to enhance the effectiveness of education and achievement of learning outcomes.

Esthetic outcome of immediately placed and nonfunctionally loaded implants in the anterior maxilla utilizing a definitive abutment: A pilot clinical trial.

BACKGROUND: Immediate dental implants placement and loading utilizing definitive abutments might save time and cost when an esthetic final result is anticipated. The objective of this prospective clinical trial was to evaluate the esthetic outcome of immediate implantation and immediate nonfunctional loading utilizing definitive abutments, with and without bony substitutes filling the peri-implant gap. MATERIALS AND METHODS: In this clinical trial study a total of 11 implants were placed utilizing a flapless immediate post extraction approach in the maxilla (second premolar to second premolar). Atraumatic extraction was performed and implants were immediately placed. The gap was either left without grafting or filled with particulate bone material. Immediate nonfunctional loading was performed utilizing a definitive abutment. The pink esthetic scores (PESs) were assessed preoperatively, at 1- and 2-year follow-up periods. Dental casts were obtained at respective time intervals; scanned, registered, and closest point distances were measured. For all statistical tests, value of P = 0.05 was set as a statistical significance level. RESULTS: The mean of PES at baseline was 9.4 ± 1.69, at 1 year was 9.5 ± 2.07, at 2 years was 10.2 ± 2.75, for the graft group 10.3 ± 2.8, and for nongrafting group was 10.2 ± 2.59. There were no statistically significant differences in PESs at baseline when compared to 1- and 2-year intervals, and for grafting group versus nongrafting group (P = 0.24). Distances between the two time points for all cases were <1 mm in all reference planes. CONCLUSION: Immediate placement and nonfunctional loading utilizing a definitive abutment appear to result in a stable result as far as esthetic outcome and alveolar process sufficiency are concerned.

Does the Use of Cone-Beam Computed Tomography Before Mandibular Third Molar Surgery Impact Treatment Planning?

PURPOSE: We aimed to investigate whether cone-beam computed tomography (CBCT) alters the treatment decision for impacted mandibular third molar (M3M) surgery when the third molars show proximity to the inferior alveolar canal (IAC) on panoramic radiography (OPG) and to examine surgeons' confidence in the various treatment options. METHODS: We performed a retrospective study evaluating a series of randomized OPG and CBCT images and answering a set of questions regarding impacted M3Ms. The anatomic risk factors studied included the proximity of M3M roots to the IAC, vertical relationship between the M3M and the IAC, and interruption of the IAC cortex by M3M roots. The primary outcome variable was the treatment decision of whether to observe, extract under local anesthesia, extract under general anesthesia, or perform coronectomy. The secondary outcome variable was confidence in the proposed treatment plan. The χ2 test was used to compare proportions and to test the differences in the treatment plan according to the studied independent variables. Binary logistic regression was used to determine the effect of anatomic factors. P < .05 was considered statistically significant. RESULTS: The study sample consisted of 132 impacted M3Ms in 71 patients. No significant differences in the proposed treatment plan were found when the imaging modalities (OPG and CBCT) were compared (P > .05). Examination of CBCT enabled detection of anatomic risk factors (P < .001). Binary logistic regression showed the absence of IAC cortex interruption to be the most significant determinant toward planning for extraction on OPG (odds ratio, 3.1; P < .005) and on CBCT (odds ratio, 5.0; P < .001). Surgeons were more confident when planning for extraction (P < .001). CONCLUSIONS: The use of CBCT provides a better understanding of the anatomic relationship between M3M roots and the IAC. However, experienced surgeons dealing with impacted M3Ms with evidence of proximity to the IAC on OPG can decide on the treatment modality without CBCT.

Assessment of the dental morphological pattern of living Jordanian Arabs suggesting a genetic drift from the Western-Eurasia pattern: A cone beam computed tomography study.

The objectives were to determine the expression frequency and sexual dimorphism of 15 dental morphological traits on the permanent dentitions of living Jordanians, and to compare the dental morphological pattern of this sample with those of 22 groups representing the various geographic regions of the world, for the purpose of assessing the population structure and genetic history of this group. Cone beam computed tomography images for the dentitions of 150 adult Jordanians (67 males, 83 females; age range = 18-58, mean ages 28.2, sd = 10.0 years) were studied in 2017. The traits were classified using the Arizona State University dental anthropology system, counted with the individual count method, and dichotomized according to the criteria of Scott & Turner for the purpose of group comparisons. Fisher's exact test for dichotomized scores was used to assess sexual dimorphism in these traits. Smith's Mean Measure of Divergence was used to measure all pairwise distance values among the groups. Statistically significant sexual dimorphism was found in two traits (i.e., UI1 shoveling and 4-cusped LM1), and apparent but statistically insignificant difference was found in three traits (i.e., UC canine mesial ridge, 3-rooted LM1, and 1-rooted LM2), all in favour of females. This study revealed that the dental pattern of Jordanians is distinct from the other reported Western Eurasian patterns and all other known dental patterns. This differentiated dental pattern suggests a genetic drift for this population from the Western Eurasian Ancestry.

Prevalence and Configuration of the Second Mesiobuccal Canal in the Permanent Maxillary First Molar in Jordanian Population Sample.

Introduction: Missing a root canal during endodontic treatment implicates the persistence of microbial infection within the root canal system. This study aims to evaluate the incidence and morphology of the second mesiobuccal canal in the maxillary first molars in the Jordanian population. Methods and Materials: Consecutive cone-beam computed tomography (CBCT) scans taken at Jordan University Hospital were assessed in this retrospective study. A total of 200 scans that were examined, 111 were included in this study. The scans that were included had to have a full view of the maxilla with at least one permanent maxillary first molar. The following data were collected: the presence of a second mesiobuccal canal, the configuration of the mesiobuccal canals, the status of the apical area and the mesiobuccal inter-orifice distance, if applicable. The prevalence and morphology of the second mesiobuccal canal was determined and its association with biological sex and right or left sidedness was measured using the Chi-Square test. Results: The prevalence of the second mesiobuccal canal in our sample of the Jordanian population was 87%, with the most common canal configuration being Vertucci type II. The average inter-orifice distance between first and second mesiobuccal canals was 1.9 ± 0.4 mm. Conclusion: This retrospective study is the first in Jordan to document the prevalence of the second mesiobuccal canal using CBCT, and it shows that the vast majority of teeth have a second mesiobuccal canal. The proper location and negotiation of this canal is of dire importance for endodontic therapy.

Unexpectedly low levels of dental morphological asymmetry suggesting developmental resilience amongst living Jordanians: A cone beam computed tomography study.

The objective was to determine the degree of fluctuating asymmetry in the expression of 13 dental morphological traits among adult Jordanians. Cone beam computed tomography images for the dentitions of 150 adult Jordanians (67 males, 83 females; age range = 18-58, mean ages 28.2, SD = 10.0 years) were studied in 2017. The traits were classified using the Arizona State University dental anthropology system, and dichotomized according to the most widely accepted criteria to define trait presence. Asymmetry was assessed using three different methods: percentage of discordance including bilateral absence cases (PDIBAC), percentage of discordance excluding bilateral absence cases (PDEBAC), and inter-side correlation (ISC) using Kendall's tau coefficient. Fisher's exact test was used to assess sexual dimorphism in the degree of asymmetry. The mean PDIBAC and the mean ISC for all the traits considered are 4.1% and 0.837, respectively. For traits observed on key teeth (mesial members of teeth districts) the mean PDIBAC and the mean ISC are 3.0% and 0.860, respectively; and for those observed on variable teeth (distal members of teeth districts) the mean PDIBAC and the mean ISC are 6.5% and 0.783, respectively. No statistically significant difference was found in the degree of asymmetry between sexes. The overall low degree of asymmetry found in the present sample (4.1%) compared to the world range of 5-15% may indicate great ability of its individuals to buffer the adverse effects of environmental stresses affecting the living Jordanians during early tooth development.

Morphometric predictors of lingual undercut depth in the posterior mandible and their relevance to immediate dental implant insertion: recommendations for CBCT / Predictores morfométricos de la profundidad de la «undecurt¼ lingual en la parte posterior de la mandíbula y su relevancia para la inserción inmediata de implantes dentales: recomendaciones para la CBCT

Deep lingual undercut (LU) is commonly encountered in the posterior mandible, and is considered a risk factor in dental implants. In this study we investigated the value of data extracted from OPGs in predicting LU depth. Such predictors might be valuable in reducing the chance of lingual plate perforation (LPP) by recommending CBCTs prior to dental implant insertion when deep LU is anticipated We aimed at assessing the following variables as potential predictors of LU depth: 1) alveolar process height (measured on OPGs), 2) alveolar process width (measured on CBCTs), and 3) the distance from apical region of dental alveoli to superior margin of IAN canal (measured on OPGs). 128 CBCTs and corresponding OPGs of posterior mandibles of 128 patients (70 females, 58 males; age range=18-87 years, mean age=45.8 years, SD=17.0 years) were used. Only dentate sites of lower first (LM1) and second molars (LM2) were considered. Four predictors of LU depth were found, the strongest was the ratio between alveolar process width (which could be assessed clinically) and alveolar process height as measured on OPGs (r=.454 at LM1 site, r=.592 at LM2 site). Predictors derived from OPG measurements might be valuable in anticipating LU depth and might be more valuable when combined with alveolar process width (which might be assessed clinically). We recommend considering the suggested predictors in assessing the need of CBCT prior to immediate dental implant insertion in posterior mandible.

El socavado lingual profundo (SLU) se encuentra comúnmente en la porción posterior de la mandíbula y es considerado un factor de riesgo en los implantes dentales. En este estudio, investigamos el valor de los datos extraídos de los OPG para predecir la profundidad del SLU. Dichos predictores podrían ser valiosos para reducir la posibilidad de perforación de la placa lingual (PPL) recomendando CBCT antes de la inserción del implante dental cuando se anticipa un SLU. El objetivo consistió en evaluar las siguientes variables como posibles predictores de profundidad de SLU: 1) altura del proceso alveolar (medida en OPG), 2) ancho del proceso alveolar (medido en CBCT) y 3) la distancia desde la región apical de los alvéolos dentales al margen superior del canal IAN (medido en OPG). Se utilizaron 128 CBCT y las OPG correspondientes de mandíbulas de 128 pacientes (70 mujeres, 58 hombres; rango de edad = 18-87 años, edad media = 45,8 años, SD = 17,0 años). Sólo se consideraron los sitios dentados de los primeros molares inferiores (LM1) y los segundos molares inferiores (LM2). Se encontraron cuatro predictores de profundidad de SLU, el más fuerte fue la relación entre el ancho del proceso alveolar (que podría evaluarse clínicamente) y la altura del proceso alveolar medida en OPG (r = 0,454 en el sitio LM1, r = 0,592 en el sitio LM2). Los predictores derivados de las mediciones de OPG podrían ser valiosos para anticipar la profundidad de SLU y podrían ser más valiosos cuando se combinan con el ancho del proceso alveolar (que podría evaluarse clínicamente). Recomendamos considerar los factores predictivos sugeridos para evaluar la necesidad de CBCT antes de la inserción inmediata del implante dental en la porción posterior de la mandíbula.

The use of a custom-made virtual template for corrective surgeries of asymmetric patients: proof of principle and a multi-center end-user survey.

AIM: To evaluate the utility of an individualized template for corrective surgeries for patients suffering from mandibular asymmetry. MATERIALS AND METHOD: Twenty patients with history of favorable clinical outcome of the correction of their mandibular asymmetry were chosen. CBCTs were taken before and 6 weeks postoperative using NewTom 3G. Each volume is mirrored and registered on the cranial base. Surface models for the mandible and its registered mirror were used to compute a template using deformable fluid registration. Surgery was simulated based of the resulting template. A multi-center survey using "Qualtrics" was conducted to gain clinical feedback of 20 surgeons/orthodontists comparing treatment outcomes. RESULTS: Twenty-three clinicians participated. More clinicians rated simulated outcome to be "Good," whereas the actual surgical outcomes were rated as "fair" and "poor." This was true for regional appraisal for the chin, Rami, and body of the mandible as well as the overall assessment of the outcome of surgeries. The gains of computer-assisted simulation tend to be greater for difficult cases especially for the body of the mandible, then the chin, and then the Ramus correction. CONCLUSIONS: This approach has the potential to optimize and increase the predictability of the outcome of craniofacial corrective surgeries for asymmetric patients.

What factors affect the severity of permanent tooth impaction?

BACKGROUND: The aim of this study was to investigate the association between the severity of permanent tooth impaction and a number of predefined factors, including tooth type, age, gender, tooth agenesis, microdontia of maxillary lateral incisor, and retained deciduous predecessors. METHODS: A sample of 2979 dental patients, aged 15 to 40 years, was surveyed by two calibrated examiners for permanent tooth impaction (excluding third molars). On panoramic radiographs, the impacted teeth were initially ranked based on their vertical, horizontal, and angular positions, and the ranking was then analysed for distribution by the predefined factors. To test the age factor, patients were divided into younger (15 to 25 yr) and older (between 25 and 40 yr) age groups. The statistical significance of the ranked vertical, horizontal, and angular positions of impacted teeth by the investigated factors was determined using the Wilcoxon-Mann-Whitney U test. RESULTS: The angular position of the impacted teeth was more severe in the older age group (P = 0.012) and in females (P = 0.018). The maxillary canine had more severe horizontal (P = 0.001) and angular (P = 0.003) impactions in females. Tooth agenesis was associated with less severe horizontal impaction (P = 0.041) in the mandibular second premolar. In addition, microdontia of the maxillary lateral incisor was associated with more severe horizontal impaction in general, and more severe horizontal (P = 0.024) and angular (P = 0.010) impaction of the mandibular second premolar in particular. Finally, our results showed that a retained deciduous predecessor was linked to a less severe vertical impaction of the mandibular second premolar (P = 0.030) and horizontal impaction of the maxillary second premolar (P = 0.037) but more severe angular impaction of the mandibular canine. CONCLUSIONS: This study suggests that the more delayed the treatment, being a female, the presence of maxillary lateral incisor with microdontia, and retained lower deciduous canines might be associated with more severe position of the impacted teeth. Because the severity of tooth impaction would follow different patterns when considering the investigated factors, it is mandatory to include such factors during dental diagnoses and the planning of preventive or interceptive interventions for young patients.

Assessment of Bone Dimensions in the Anterior Maxilla: A Cone Beam Computed Tomography Study.

PURPOSE: To evaluate labial and palatal bone thickness at the maxillary anterior teeth as well as distance from cemento-enamel junction (CEJ) to bone crest using cone beam computed tomography (CBCT). MATERIALS AND METHODS: Measurements were obtained for maxillary anterior teeth of 120 subject CBCT volumes including thickness of labial and palatal plates of bone (coronal, middle, and apical thirds), and distance between CEJ and alveolar bone crest mid-labially, mesially, and distally. RESULTS: The mean value of bone thickness at coronal, middle, and apical thirds of the labial side for central incisor roots were respectively: 0.73, 0.69, 0.60 (mm), for lateral incisors: 0.70, 0.61, 0.49 (mm), and for canines: 0.74, 0.53, 040 (mm). The thickness of palatal bone was significantly larger. The mean distance between CEJ and mid-labial bone crest for all sites was 2.16 mm. CONCLUSION: Labial bone thickness is thin in the vast majority of maxillary anterior teeth. Use of CBCT facilitates planning for immediate implant placement and is helpful in the decision-making process when further bone augmentation is needed.

Age prediction in the adult based on the pulp-to-tooth ratio in lower third molars: a cone-beam CT study / Predicción de edad en el adulto basada en la proporción pulpa-a-diente en terceros molares inferiores: un estudio por TC de haz de cono

Estimation of age-at-death is an integral part of the identification process of individuals in many forensic odontology cases where their identity cannot be determined by visualization or other ways. Dental age estimation in the adult is more challenging as most of the dentition is completely developed by 18 years of age. This study employs a mesio-distal (MD) pulp-to-tooth ratio taken at the neck of lower third molars (LM3) to provide an estimation of age at the time of radiographic imaging based on the well-known fact that pulp volume tends to decrease with advancing age due to continued apposition of secondary dentine throughout adulthood. A total of 155 Cone-beam computed tomography (CBCT) radiographs of LM3s for a random sample of 155 Jordanian Arabs (80 females, 75 males; age range= 18-58 years, mean age= 28.2 years, SD =10.0 years) were used. Both pulp and tooth MD diameters were measured at the neck. MD pulp-to-tooth ratios for LM3s were linearly regressed against age. Statistically significant negative association was found between an individual's age at the time of imaging and the MD pulp-to-tooth ratio taken at the neck. Specifically, the strength of the association is r= -0.361, which means only 13.0 % of the variation in age can be explained by the MD pulp-to-tooth ratio taken at the neck. Therefore, it was concluded that MD pulp-to-tooth ratio taken at the neck of LM3s is not a reliable predictor of chronological age in adults, possibly due to the large variation in the timing of LM3 development.

La estimación de la edad es una parte integral del proceso de identificación de los individuos, en muchos casos en odontología forense donde la identidad no puede ser determinada por visualización u otras formas. La estimación de la edad dental en el adulto es aún más difícil ya que la mayor parte de la dentición se desarrolla completamente a los 18 años de edad. Este estudio emplea una relación mesio-distal (MD) de pulpa a diente tomada a nivel del cuello de los terceros molares inferiores (LM3) para proporcionar una estimación de la edad en el momento de la imagen radiográfica basada en que el volumen de pulpa tiende a disminuir con el avance de la edad debido a la continua posición de la dentina secundaria a lo largo de la edad adulta. Se examinaron un total de 155 radiografías de LM3 en una muestra aleatoria de 155 árabes jordanos (80 mujeres, 75 varones), rango de edad = 18-58 años, edad media = 28,2 años, DE = 10,0 años. Específicamente, la fuerza de la asociación es r=0,361, lo que significa que sólo el 13,0 % de la variación en la edad puede explicarse por la proporción pulpa-a-diente.

Prevalence and distribution of dental anomalies: a comparison between maxillary and mandibular tooth agenesis.

INTRODUCTION: The aim of this study was to compare the pattern and prevalence of associated dental anomalies between maxillary and mandibular tooth agenesis (hypodontia). METHODS: A sample of 3315 dental patients, aged 8.6 to 25.4 years, was surveyed for tooth agenesis (excluding third molars): 106 subjects were diagnosed with maxillary hypodontia (group 1) and 70 with mandibular hypodontia (group 2). Both groups were examined for the following dental anomalies: retained deciduous molars, infraocclusion of deciduous molars, impaction, microdontia of maxillary lateral incisors, supernumerary teeth, transposition, transmigration, and ectopic eruption of the permanent molars. For statistical testing, the chi-square test (P <0.05) was used to compare the occurrences of these anomalies among the groups. RESULTS: We found that 77.5% of the patients in the mandibular hypodontia group had at least 1 dental anomaly compared with 49.5% in the maxillary hypodontia group (P <0.0001). The only dental anomaly with a significantly increased prevalence in the maxillary hypodontia group compared with the mandibular hypodontia group was microdontia of the maxillary lateral incisors (groups 1, 46.7%; group 2, 12.9%; P <0.0001). On the other hand, the prevalences of retained deciduous molars (group 1, 9.4%; group 2, 60.0%), infraoccluded deciduous molars (group 1, 0.9%; group 2, 7.1%), and impacted teeth (group 1, 22.6%; group 2, 38.6%) were significantly higher in the mandibular hypodontia group. The prevalences of supernumerary teeth, transposition, transmigration, and ectopic eruption of permanent molars were low and not significantly different between the groups. CONCLUSIONS: Tooth agenesis isolated to the maxilla is frequently associated with microdontia of the maxillary lateral incisors, whereas tooth agenesis isolated to the mandible is frequently associated with retained deciduous molars, infraoccluded deciduous molars, and impacted teeth. The results of this study may provide additional evidence supporting the field-specific genetic control theory for dental development in both jaws.