Comparison of digital protocols for the measurement of peri-implant marginal bone loss

Background

The measurement of peri-implant marginal bone loss is currently carried out using digital methods of radiographic analysis assisted by various types of software. The purpose of this study was to compare the characteristics of three different softwares: specific radiology software for the development and visualization of radiological images in DICOM format (3Dicom Viewer®), advanced level software for professional editing of bitmap images (or raster graphics) (Adobe Photoshop®), and mid-level software for processing bitmap-type images, programmed in Java and in the public domain (ImageJ®).

Material and Methods

It was verified that the three softwares used are valid for the measurement of peri-implant marginal bone loss provided that the appropriate protocol is fulfilled.

Results

The results showed no significant differences between Adobe Photoshop® and ImageJ® with respect to 3Dicom Viewer® in the measurements of mesial and distal bone loss of the implants, without influence of the dental sector where they were located.

Conclusions

The measurements made with ImageJ® looked more like those of the control software (3Dicom Viewer®) than those of Adobe Photoshop®, but with a greater degree of dispersion. Thus, Adobe Photoshop® is a slightly inaccurate method but with less dispersion. Key words:Digital measurement, measurement software, peri-implant marginal bone loss, implants.

Relationship between perception of smile esthetics and orthodontic treatment in Spanish patients

One of the main objectives of orthodontic treatment is to achieve an esthetic smile. This study set out to analyze differences in the perception of smile esthetics among patients before and after receiving orthodontic treatment. 250 Spanish patients analyzed a single photograph in which, by means of computer software, midline diastema, black triangle, gingival margin of the left central incisor, and gingival ("gummy") smile were altered. Each patient analyzed these images before and after undergoing orthodontic treatment. Patients scored the photographs on a scale from 1 to 10. Statistical analyses of each group's level of perception were carried out, identifying significant differences in evaluations before and after treatment, and in relation to subjects' gender and age. Patients presented significant differences in the esthetic perception of midline diastema and gummy smile anomalies after they had completed orthodontic treatment. Gender influenced the perception of smile esthetics, whereby women were significantly more critical of midline diastema, black triangle and gingival margin of the upper central incisor than men. The age variable also showed significant differences in the perception of midline diastema and black triangle anomalies. The perception of smile esthetics of some dental anomalies changes as a result of orthodontic treatment. Gender influences the perception of some of the dental anomalies studied.

The 100 most-cited articles in orthodontics: A bibliometric study

OBJECTIVES:

To identify and analyze the 100 most-cited articles in orthodontics indexed in the Web of Science Category of "Dental, Oral Surgery and Medicine" from 1946 to 2016.

MATERIALS AND METHODS:

On hundred articles were identified in a search of the database of the ISI Web of Science and Journal Citation Reports, applying the truncated search term "orthodon*." Records were manually refined and normalized to unify terms and to remove typographical, transcription, and/or indexing errors.

RESULTS:

The 100 most-cited articles were published between 1946 and 2012, with numbers of citations ranging from 115 to 881. Of the 251 authors participating, 87.65% published a single work, while three authors published four works. Most of the authors with several citations were from the United States, although the University of Oslo produced the highest number of frequently cited works. Most of the articles were clinical studies, and the most frequently cited topic was mini-implants. It was noted that self-citation could be a potential cause of bias in bibliometric analysis.

CONCLUSIONS:

This bibliometric citation analysis reveals new, useful, and interesting information about scientific progress in the field of orthodontics.

Dental measurements and Bolton index reliability and accuracy obtained from 2D digital, 3D segmented CBCT, and 3d intraoral laser scanner

Background

To compare the reliability and accuracy of direct and indirect dental measurements derived from two types of 3D virtual models: generated by intraoral laser scanning (ILS) and segmented cone beam computed tomography (CBCT), comparing these with a 2D digital model.

Material and Methods

One hundred patients were selected. All patients’ records included initial plaster models, an intraoral scan and a CBCT. Patients´ dental arches were scanned with the iTero® intraoral scanner while the CBCTs were segmented to create three-dimensional models. To obtain 2D digital models, plaster models were scanned using a conventional 2D scanner. When digital models had been obtained using these three methods, direct dental measurements were measured and indirect measurements were calculated. Differences between methods were assessed by means of paired t-tests and regression models. Intra and inter-observer error were analyzed using Dahlberg´s d and coefficients of variation.

Results

Intraobserver and interobserver error for the ILS model was less than 0.44 mm while for segmented CBCT models, the error was less than 0.97 mm. ILS models provided statistically and clinically acceptable accuracy for all dental measurements, while CBCT models showed a tendency to underestimate measurements in the lower arch, although within the limits of clinical acceptability.

Conclusions

ILS and CBCT segmented models are both reliable and accurate for dental measurements. Integration of ILS with CBCT scans would get dental and skeletal information altogether.

Key words:CBCT, intraoral laser scanner, 2D digital models, 3D models, dental measurements, reliability.

Cross-sectional human study of soft tissue chin (STC) thickness in adult patients in relation to sex, facial pattern and skeletal class

PURPOSE

The aim of this study was to study the relations between the soft tissue chin (STC) and sex, skeletal class, and facial pattern; and to describe the shape and behavior of the STC.

METHODS

385 non-growing patients were selected, 206 women and 179 men, with a mean age of 28.8 years (SD 4.2). Patients were divided into groups by skeletal class (class I, II or III) and facial pattern (brachyfacial, mesofacial or dolichofacial). STC thicknesses were measured at pogonion (Pg), soft pogonion (Pg'), gnathion (Gn), soft gnathion (Gn'), menton (Me) and soft menton (Me') in the CBCTs.

RESULTS

Sexual dimorphism was observed at Pg-Pg' and Me-Me'. STC thickness was not related to skeletal class but related to facial pattern. Pg-Pg' and Me-Me' measurements showed significant differences to the combination of skeletal class/facial pattern. STC thickness was not homogenous in terms of shape and behavior.

CONCLUSIONS

The results provide evidence of a strong but complex relationship between sex, facial pattern, skeletal class and STC thickness; for this reason, each patient must be evaluated individually before undergoing orthodontics or orthognathic surgery involving the mandible and the mandibular symphysis.

Analysis of scientific production in spanish implantology

BACKGROUND

The aim of the study was to quantify the scientific productivity of researchers, organizations, and regions in Spain that publish articles on implantology in dental journals indexed in Journal Citation Reports.

MATERIAL AND METHODS

A search was conducted among the core collection of Thomson Reuters' Web of Science database, on the basis of its broad thematic and geographic coverage of health sciences. The search identified original articles - the main vehicle for the dissemination of research results. The search was conducted in July 2016, applying the truncated search term 'implant*' to locate original articles on implantology and its derivative forms. The search was conducted within the topic field (title, keywords and abstract) and two inclusion criteria were applied: documents denominated as articles were included; and articles categorized as Web of Science Medicine Dentistry and Oral Surgery. Finally only articles for which one of the participating organizations was located in Spain were selected.

RESULTS

The final search identified a total of 774 records. The period 1988 to 2015 saw an exponential growth in scientific production, especially during the last 10 years. Clinical Oral Implants Research and Medicina Oral Patologia Oral y Cirugia Bucal (Oral Medicine, Oral Pathology, and Oral Surgery) were the most productive journals. Collaborative networks among authors and among institutions increased and this increase was related to the improving quality of the publications.

CONCLUSIONS

Bibliometric analysis revealed a significant growth in the quantity and quality of Spanish implantology literature. Most key bibliometric indicators demonstrated upward trends. Key words:Bibliometric analysis, publication, keywords, implantology, implant.

Influence of skeletal class in the morphology of cervical vertebrae: A study using cone beam computed tomography

OBJECTIVES

To quantify the prevalence of cervical vertebrae anomalies and to analyze any association between them and skeletal malocclusions or head posture positions in the same study.

MATERIALS AND METHODS

Two hundred forty patients who were attending the Department of Orthodontics of the University of Valencia for orthodontic treatment were selected and divided into three groups: skeletal Class I (control group, 0° <ANB < 4°), Class II (ANB ≥ 4°), and Class III (ANB ≤ 0°) according to ANB Steiner angle. The morphology of the first five cervical vertebrae was analyzed with cone beam computed tomography to identify any anomalies. Intra- and interobserver error methods were calculated.

RESULTS

Dehiscence and fusion of one unit (both 23.3%) and partial cleft (11.7%) were the most frequent anomalies, while occipitalization was the least common (3.3%). Dehiscence anomaly was observed when the control group was compared with Classes II and III and partial cleft anomaly when Class I was compared with Class III. Furthermore, NSBa and ss-N-sm/ANB angles were associated with partial cleft anomaly, while NSL/NL angle and extended head posture were associated with fusion anomaly.

CONCLUSIONS

Fusion, dehiscence, and partial cleft were the most frequent cervical vertebrae anomalies. Dehiscence and partial cleft were found to present statistically significant differences between Class I and Classes II and III. Cervical vertebrae anomalies and head posture were associated with fusion.

A comparative study of the pharyngeal airway space, measured with cone beam computed tomography, between patients with different craniofacial morphologies

PURPOSE

The present study aims to determine any existing association between airway dimensions, measured with cone beam computed tomography (CBCT), and the different patient craniofacial morphologies.

MATERIAL AND METHODS

Sixty CBCT (Dental Picasso Master 3D) images, from patients treated at the Orthodontics Master at Valencia University were selected. The program InVivoDental 5.1 was used to visualize sections, analyze three-dimensional images, and perform airway measurements in the three planes of the space. Intra- and interobserver error methods were recorded. After that, measurements at three different levels of the airway (upper, medium, lower) were taken, in both the anteroposterior and transversal directions of the airway space. The area (mm(2)) of the airway space at the three levels was also measured.

RESULTS

In the anteroposterior airway measurements, there were differences between the measurements by level. The magnitude of these differences depended on the skeletal pattern of the individual. In the transversal airway measurements and in the area airway measurements, there were no differences according to the skeletal pattern. However, in the transversal direction, measurements in the lower level were significantly higher than in the superior level in all cases. When measuring the area, significantly higher measurements in the upper level were recorded. The homogeneity between medium and lower levels decreased gradually from class I to class III subjects.

CONCLUSIONS

No statistically significant results were observed that related the anteroposterior and vertical skeletal craniofacial morphology with airway dimensions, although some specific associations have been detected for certain airway levels or for pattern combinations.

New regression equations for predicting human teeth sizes

INTRODUCTION

The aims of the study were; to evaluate the applicability of the Moyers and Tanaka-Johnston Methods to individuals with a Spanish ancestry, to propose new regression equations using the lower four permanent incisors as predictors for the sum of the widths of the lower permanent canine and premolars, and to compare the new data to those from other populations.

METHODS

A total of 359 Spanish ancestry adolescents were selected. Their dental casts were measured using a 2D computerized system. Real teeth measurements were compared with those predicted using Moyers probability tables and Tanaka and Johnston equations, and standard regression equations were then developed.

RESULTS

Results showed that Upper and Lower Canine and Premolar (UCPM, LCPM) predictions are quite different depending on the used method. Moyers tables can only be validly applied to a 75% percentile for the mandible in both, males and females, 85% in males and 90-92% in females.

CONCLUSIONS

Moyers predictions tend to underestimate UCPM and LCPM whereas Tanaka-Johnston predictions tend to overestimate them. Equations for estimating the combined width of the unerupted canine and premolars were; Male: UCPM = 12.68 + 0.42 LI and LCPM = 11.71 + 0.44 LI. Female: UCPM = 12.06 + 0.43LI and LCPM = 10.71 + 0.46 LI.

Anxiety before extraction of impacted lower third molars

Objetives: Assess levels of trait anxiety, state anxiety and dental anxiety before extraction of lower third molars and check the correlation and reliability of the scales used for the measurement of preoperative anxiety. Study Design: A prospective study of patients treated with extraction of a lower third molar between September 2010 to December 2010 was carried out. A total of 125 patients were included in the study. All of them were patients of the Oral Surgery and Implantology Department (Valencia University Medical and Dental School, Valencia, Spain). Before surgery, patients had to complete a preoperative protocol with 4 scales: the STAI-T (State-Trait Anxiety Inventory-Trait) for measuring trait anxiety, the STAI-S (State-Trait Anxiety Inventory-State) for measuring state anxiety, and DAS (Dental anxiety Scale of N. Corah) and APAIS (Amsterdam Preoperative anxiety and Information Scale) for measuring dental anxiety. Results: Patients undergoing extractions of an impacted lower third molar showed low levels of trait anxiety and moderate levels of state anxiety and dental anxiety. Higher levels of trait anxiety were obtained for older patients. Women had higher mean levels of dental anxiety and state anxiety that men with a statistically significant difference in STAI-S scales, DAS, and APAIS. Patients with higher trait anxiety and state anxiety showed higher levels of dental anxiety. A significant correlation (p ≤ 0.01) (p = 0.00) was found between the four scales used to measure anxiety. The scale showed higher correlation was STAI-S scale. The 4 scales showed high reliability (α of C.> 0.80). Conclusions: Patients with highest levels of trait anxiety and state anxiety, had more dental anxiety. The STAI-T, STAI-S, DAS and APAIS scales provided useful information about anxiety before the extraction of lower impacted third molars. The STAI-S is the scale with highest correlation and reliability.

Key words:Extraction of impacted lower third molars, preoperative anxiety, dental anxiety, trait anxiety, state anxiety.

Relationship between indication for tooth extraction and outcome of immediate implants: A retrospective study with 5 years of follow-up

Objectives: The aims of this retrospective study were to evaluate the survival rate of a series of immediate implants after 3 years of follow-up and to study the relationship between survival and indication for tooth extraction. Study Design: A retrospective study of patients treated with immediate implants between January 2003 and December 2008 was carried out. All patients receiving at least one post-extraction implant and a minimum follow-up of 5 years were included. Results: After 60 months, 30 immediate implants had been lost in 17 patients, yielding a total implant success rate of 93.8%. None of the implants placed failed after the extraction of included canines (100% success rate). In 20 failed implants the reason for extraction had been severe periodontal disease (91.8% SR), in 4 endodontic failure (88.6%SR), in 3 unrestorable caries (95.9% SR), in 1 untreatable fracture (95.2% SR) and in 2 improvement of prosthetic design (98.1% SR). No statistically significant influence was found between immediate implant failure and the reason for tooth extraction (p=0.11). Conclusions: The use of immediate implants is a successful alternative to replace missing teeth for severe periodontal disease, periapical pathology or by decay or untreatable fractures. Some reasons, such as periodontal disease itself is associated with a success rate significantly below the overall average. Similarly, the prosthetic design is associated with a better prognosis than all other reasons.

Key words:Tooth extraction, immediate implants, success rate.

Comparative study of mandibular linear measurements obtained by cone beam computed tomography and digital calipers

Objectives: Cone beam computed tomography (CBCT) is an innovative dental of imaging system characterized by rapid volumetric imaging with patient exposure to a single dose of radiation. The present study was carried out to compare the linear measurements obtained with CBCT and digital caliper in 20 mandibles from human cadavers. Study design: A total of 4800 linear measurements were measured between different mandibular anatomical points with CBCT and digital caliper. The real measurements were defined as those obtained with the digital caliper. Posteriorly, the mandibles were scanned to obtain the CBCT images, with software-based measurements of the distances. Results: The measurements obtained with the digital caliper were greater. The CBCT technique underestimated distances greater than 100 mm. Conclusions: CBCT allows to obtain linear mandibular anatomical measurements equivalent to those obtained with digital caliper. The differences existing between both methods were clinically acceptable.

Key words:Computed tomography, cone beam CT, accuracy, reliability, digital caliper.

Smile esthetics from odontology students' perspectives

OBJECTIVES

To analyze the perception of smile esthetics and its alterations in dental degree students; to determine whether there are differences in that perception among students in different study years on those courses and between genders; and to determine if the circumstance of having received prior orthodontic treatment could influence that perception.

MATERIAL AND METHODS

Students (n = 192) in different study years of the dental degree course at the University of Valencia, Spain, analyzed two photographs of a patient in which, by means of computer software, midline diastema, upper and lower midlines, crown length of the maxillary right central incisor, occlusal cant, and "gummy" smile were altered. Students assessed the photographs on a scale from 1 to 10. Statistical analyses for assessing each group's level of perception were carried out.

RESULTS

After checking the validity of the study, it was observed that the students' ability to detect alterations in smile esthetics did not improve over their degree courses, given that the differences do not present a linear development. There were no differences between genders and between those who had or had not undergone an orthodontic treatment.

CONCLUSIONS

There are no statistically significant differences between the results of students in different study years or between genders. The circumstance of having undergone prior orthodontic treatment is not a determining factor in the ability to perceive such anomalies.

Evaluation of the validity of the Bolton Index using cone-beam computed tomography (CBCT)

AIMS

To evaluate the reliability and reproducibility of calculating the Bolton Index using cone-beam computed tomography (CBCT), and to compare this with measurements obtained using the 2D Digital Method.

MATERIAL AND METHODS

Traditional study models were obtained from 50 patients, which were then digitized in order to be able to measure them using the Digital Method. Likewise, CBCTs of those same patients were undertaken using the Dental Picasso Master 3D® and the images obtained were then analysed using the InVivoDental programme.

RESULTS

By determining the regression lines for both measurement methods, as well as the difference between both of their values, the two methods are shown to be comparable, despite the fact that the measurements analysed presented statistically significant differences.

CONCLUSIONS

The three-dimensional models obtained from the CBCT are as accurate and reproducible as the digital models obtained from the plaster study casts for calculating the Bolton Index. The differences existing between both methods were clinically acceptable.

[Etiology and risk factors for a first episode of cerebral isquemia in young adults]

INTRODUCTION

To determinate the etiology and risk factors for a first episode of cerebral ischemia in young adults at three hospitals of Lima and Callao-Peru.

METHODS

Multicentric study carried out at three national hospitals in Lima. The sample included 30 patients with a first episode of stroke and 60 controls matched by age and sex 2:1 with the patients. Serum biochemistry studies, EKGs and echocardiograms were done. Etiologies were classified based on the classification of Baltimore-Washington Cooperative Young Stroke Study.

RESULTS

The most frequent etiologies were cardiac embolism and atherosclerotic valvular heart disease, which were 30% of the cases (9 patients) each one. Hypertriglyceridemia (p=0.014), valvular heart disease (p=0.001) and hormonal contraception/replacement therapy (p=0.002) were independent risk factors for a first episode of cerebral ischemia in peruvian young adults. Motor deficiency was the most frequent presentation (50.0%). Intracraneal hypertension and urinary tract infection were the most frequent complications during acute ischemia and mortality was raised up to 10%.

CONCLUSIONS

The hypertriglyceridemia, valvular heart disease and the use of oral contraceptives are independent risk factors for a first episode of ischemia in young adults from three hospitals of Lima and Callao. The most frequent etiologies were cardiac embolism and atheroesclerotic valvular heart disease.

Influence of first and second premolar extraction or non-extraction treatments on mandibular third molar angulation and position. A comparative study

The mandibular third molar (3M) is the tooth that is most often impacted, with lack of space being one of the reasons. In some orthodontic treatments, premolars are extracted in order to create space. The aims of our study are: firstly, to assess the changes in the angulation and position of the 3M in cases treated either with or without extraction of the first or second premolars; secondly, to analyse the variation in the gonial angle and the degree of inclusion of the 3M; and lastly, to establish a predictive impaction model for 3M. This study included 88 patients: 28 patients treated with extractions of first premolars, 30 with second premolars and 30 without. The initial and final orthopantomography was analysed and the angulation of the 3M was measured, a new variable being created to determine the degree of 3M inclusion in the mandibular ramus. The results show that the angulation of 3M improves with time, regardless of treatment, and presents a greater disinclusion in cases treated with extractions. The gonial angle tends to diminish with age in all cases. The conclusions suggest that other factors may influence the angulation and position of 3M and that it is not possible to establish a predictive impaction model.