127 research outputs found
The combined use of corticotomy and clear aligners: a case report
OBJECTIVE:
  To describe an orthodontic treatment that combines an esthetic approach (clear aligners) with surgery (alveolar corticotomy).
MATERIALS AND METHODS:
  A patient with moderate dental crowding and Class I skeletal and molar relationships was selected. Orthodontic records of the patient were taken. Periodontal indexes, oral health-related quality of life (OHRQoL), and treatment time were evaluated. After we reflected a full-thickness flap beyond the teeth apices, the cortical bone was exposed on the buccal aspect and a modified corticotomy procedure was performed. Interproximal corticotomy cuts were extended through the entire thickness of the cortical layer, just barely penetrating into medullary bone. Orthodontic force was applied on the teeth immediately after surgery.
RESULTS:
  Total treatment time was 2 months. Periodontal indexes were improved after correction of crowding. A deterioration of OHRQoL was limited to 3 days following surgery.
CONCLUSION:
  This case report may encourage the use, limited to selected cases, of corticotomy associated with clear aligners to treat moderate crowding
The combined use of computer-guided, minimally invasive, flapless corticotomy and clear aligners as a novel approach to moderate crowding: a case report
The aim of this case report was to describe an innovative orthodontic treatment
method that combined surgical and orthodontic techniques. The novel method
was used to achieve a positive result in a case of moderate crowding by
employing a computer-guided piezocision procedure followed by the use of clear
aligners. A 23-year-old woman had a malocclusion with moderate crowding. Her
periodontal indices, oral health-related quality of life (OHRQoL), and treatment
time were evaluated. The treatment included interproximal corticotomy cuts
extending through the entire thickness of the cortical layer, without a fullthickness
flap reflection. This was achieved with a three-dimensionally printed
surgical guide using computer-aided design and computer-aided manufacturing.
Orthodontic force was applied to the teeth immediately after surgery by using
clear appliances for better control of tooth movement. The total treatment time
was 8 months. The periodontal indices improved after crowding correction, but
the oral health impact profile showed a slight deterioration of OHRQoL during
the 3 days following surgery. At the 2-year retention follow-up, the stability of
treatment was excellent. The reduction in surgical time and patient discomfort,
increased periodontal safety and patient acceptability, and accurate control of
orthodontic movement without the risk of losing anchorage may encourage the
use of this combined technique in appropriate cases
Accelerating orthodontic tooth movement: a new, minimally-invasive corticotomy technique using a 3D-printed surgical template
Background: A reduction in orthodontic treatment time can be attained using corticotomies. The aggressive nature
of corticotomy due to the elevation of muco-periosteal flaps and to the duration of the surgery raised reluctance
for its employ among patients and dental community. This study aims to provide detailed information on the
design and manufacture of a 3D-printed CAD-CAM (computer-aided design and computer-aided manufacturing)
surgical guide which can aid the clinician in achieving a minimally-invasive, flapless corticotomy.
Material and Methods: An impression of dental arches was created; the models were digitally-acquired using a 3D
scanner and saved as STereoLithography ( STL ) files. The patient underwent cone beam computed tomography
(CBCT): images of jaws and teeth were transformed into 3D models and saved as an STL file. An acrylic template
with the design of a surgical guide was manufactured and scanned. The STLs of jaws, scanned casts, and acrylic
templates were matched. 3D modeling software allowed the view of the 3D models from different perspectives
and planes with perfect rendering. The 3D model of the acrylic template was transformed into a surgical guide
with slots designed to guide, at first, a scalpel blade and then a piezoelectric cutting insert. The 3D STL model of
the surgical guide was printed.
Results: This procedure allowed the manufacturing of a 3D-printed CAD/CAM surgical guide, which overcomes
the disadvantages of the corticotomy, removing the need for flap elevation. No discomfort, early surgical complications
or unexpected events were observed.
Conclusions: The effectiveness of this minimally-invasive surgical technique can offer the clinician a valid alternative
to other methods currently in us
Miniscrew-supported distal jet versus conventional distal jet appliance : a pilot study
Maxillary molar distalization is the most frequently used nonextraction treatment in the correction of Class II malocclusion. The use of traditional intra-oral devices shows unreliable results. Nowadays the use of miniscrew-supported appliances helps prevent anchorage loss. The aim of this pilot study is to compare the amount of upper first molar distalization and the dentoalveolar side effects using traditional distal jet appliance and miniscrew-supported distal jet appliance. 20 patients were randomly assigned to receive a treatment with miniscrew-supported distal jet appliance (Group A) or with traditional distal jet appliance (Group B). To ensure a safe and minimally invasive miniscrew insertion a surgical guide was used. Digital models and lateral cephalograms were obtained and analyzed before orthodontic treatment and at 6-month follow-up. Intergroup differences were determined using T- test. The significance was set at p ?0.05. The intra-operator reliability was evaluated using a 2 sample T-test. The difference was not statistically significant (P ?0.05 ), demonstrating an intra-operator reliability. In Group A, a greater maxillary first molar distalization was recorded (P=0.002). Considering the dentoalveolar side effects, in Group A, a spontaneous distalization of the first premolars and a retroclination of central incisors were determined. In Group B, the first premolars tipped mesially with a proclination of the maxillary central incisors. Miniscrew-supported distal jet appliance achieved a greater first molar distalization at 6-month follow-up and did not cause dento-alveolar side effects, such as the mesial drift of the premolars and the incisors
Etiological factors in second mandibular molar impaction
Objectives: The impaction of the second mandibular molar (MM2) has recently become more prevalent. Several
etiological hypothesis have been proposed to investigate the association between skeletal features and impaction of
MM2. The aims of this study were to analyze the skeletal features in patients with MM2 impaction and the association
between arrested eruption of MM2 and the presence of the third mandibular molar (MM3).
Study Design: In this retrospective study 48 subjects from 3,530 Caucasian orthodontic patients with MM2 impaction
were included in a study group (SG) and compared to a control group (CG) of 200 subjects without MM2 impaction.
Panoramic radiographs evaluated the presence or absence of the MM3 germ. Cephalometric analysis was
performed to evaluate linear and angular skeletal values. For the statistical analysis, descriptive statistics, Student'fs
t-test, 'Ô2 test and odds ratio (OR) were used.
Results: The paired comparisons between SG and CG showed in cephalometric analysis both a reduced mandibular
gonial angle (ArGoMe) and lowered Jarabak'fs polygon value with a statistically significant difference (P. 0.05).
MM3 was statistically significant associated (P. 0.05) with MM2 impaction but it is not a risk factor (OR 0.817).
Conclusions: Subjects with MM2 impaction show a vertical condylar growth direction. MM3 is not a risk factor
for MM2 impaction
Mirror imaging of impacted and supernumerary teeth in dizygotic twins: a case report
Background: Mesiodens is the most common type of supernumerary tooth found in the premaxilla. It might be
discovered during the clinical examination as a casual finding on a radiograph or as the cause of an unerupted
maxillary central incisor. The genetic transmission of supernumerary and impacted teeth is poorly understood.
Mirror imaging in twins has been reported frequently in relation to several unilateral dental anomalies including
mesiodens. This phenomenon is the appearance of an asymmetrical feature or anomaly occurring on the right side
of one twin but on the left side of the other twin. The event of mesiodens mirror imaging in monozygotic twins has
been described in literature.
Results: This is the first reported case of mesiodens mirror imaging in dizygotic twins. The described mesiodens
caused the eruption failure of maxillary permanent incisors. The supernumerary teeth were removed to facilitate the
spontaneous eruption of the impacted permanent maxillary incisors.
Clinical Implications: Studies related to supernumerary teeth can be useful to clinicians in the early diagnosis of
this anomaly. Clinical and radiographic examinations provide a correct therapeutic approach
The effects of a common stainless steel orthodontic bracket on the diagnostic quality of cranial and cervical 3T-MR images: a prospective, case-control study
Abstract
OBJECTIVES:
To evaluate the effect of orthodontic stainless steel brackets and two different types of archwires (stainless steel and nickel-titanium) on the diagnostic quality of 3T-MR images.
METHODS:
This prospective, case-control study was conducted following STROBE guidelines. The imaging protocol consisted of the axial Fluid Attenuated Inversion Recovery (FLAIR) and axial oblique double echo proton density (PD) and weighted/turbo spin echo (TSE) T2-weighted sequences for brain, paranasal sinuses and cervical region evaluation; sagittal TSE T2w, sagittal TSE T1w and axial T2* Gradient echo sequences (GRE) sequences for the cervical vertebrae; axial and coronal TSE T2w images for the head and neck structures; and sagittal, axial and coronal PD and TSE T2-weighted sequences for the temporo-mandibular joint. Two experts in neuroradiology evaluated the images. The statistical analysis was performed at the level of anatomical districts. The following statistical methods were used: descriptive statistics, Cohen's kappa coefficient (k), Kruskal-Wallis test, pairwise comparisons using the Dunn-Bonferroni approach. Significance was set at p≤0.05.
RESULTS:
80 patients were included, providing 80 MRI. The presence of stainless steel brackets with or without archwires negatively influenced the MR images of the cervical region, paranasal sinuses, head and neck region and cervical vertebrae but did not influence the MR images of brain and temporomandibular joint regions.
CONCLUSIONS:
Patients with a stainless steel multi-bracket orthodontic appliance should remove it before cervical vertebrae, cervical region, paranasal sinuses and head and neck MRI scans. The brain and temporomandibular joint regions MRI should not require the removal of such appliances
Evaluation of alveolar cortical bone thickness and density for orthodontic mini-implant placement
Objective: Mini-implant stability is primarily related to bone quality and quantity. This study evaluated alveolar
cortical bone thickness and density differences between interradicular sites at different levels from the alveolar
crest, and assessed the differences between adolescents (12-18 years of age) and adults (19-50 years of age), males
and females, upper and lower arch, anterior and posterior region of jaws and buccal and oral side.
Study Design: In this retrospective study, 48 Computed Tomography scans, performed for oral surgery purposes
were selected from dental records of 3,223 Caucasian orthodontic patients.
The SimPlant software (Materialise, Leuven, Belgium) was used to measure cortical bone thickness and density
at 13 interradicular sites and four bone levels ( 2,4,6 and 8 mm ). For the statistical analysis descriptive statistics,
Student's t-test and Pearson correlation coefficient were used.
Results: Statistically significant differences in alveolar cortical bone thickness and density between age, gender, sites
and sides were found (P<0.05). The Pearson correlation coefficient demonstrated a significant linear increasing
of thickness and density from crest to base of alveolar crest (P.0.05).
Conclusion. Adults show a thicker alveolar cortical bone than adolescents. Alveolar cortical bone thickness and
density were greater in males than in females, in mandible than in maxilla, in the posterior region than the anterior,
in oral than buccal side. There is an increase of thickness and density from crest to base of alveolar crest
Morphological and topographical characteristics of posterior supernumerary molar teeth: an epidemiological study on 25,186 subjects
Objectives: To investigate the prevalence , gender difference , arch , morphology and position within the arch of
supernumerary molar (SM) teeth in a referred Italian Caucasian population.
Study
D
esign: Records of 25,186 young patients were evaluated. Only data related to supernumerary teeth in the
posterior region of the jaws were analyzed. The diagnosis of hyperdontia was formulated during the clinical and
radiological examinations based on panoramic radiographs. Statistical analysis was conducted at level of subjects
in the assessment of prevalence of SMs and sex ratio. Statistical analysis was conducted at level of teeth according to their morphological and topographic characteristics. The analysis of association between supernumerary
morphology and arch, between supernumerary position and arch and between morphology and position was
performed using the χ2 test (P≤ 0.05).
Results: 61 posterior supernumerary teeth were found in 45 patients. The male to female ratio was 2.5:1 ;the
mean age was 21.23 (IC:95%).The SMs were found more frequently in the maxilla (62.3%) than in the mandible;
supernumerary teeth (60.7%) were more frequent than supplemental teeth. The SMs were mostly of tuberculate
shape (56.8%) and paramolars teeth (64.9%) were more common than distomolars. 54% of teeth were erupted in
the arch. No statistically significant relationship were found between the supernumerary teeth shape and the arch
(
P
= 0.087) , between supernumerary teeth position and the arch (
P
=0.511) and between morphology and position
(
P
=0.216).
Conclusions: Epidemiological studies related to supernumerary teeth can be useful to clinicians in the early diagnosis of this anomaly. In this retrospective study the prevalence of SMs was 0.18%. SMs were more frequent
in males and in the maxilla. Supernumerary were more frequent than supplemental; the conical morphology and
paramolar position were the most common shape and position
Impaction of permanent mandibular second molar: a retrospective study
Objective: To determine the prevalence of impacted mandibular second molar (MM2) and the association between
MM2 impaction and crowding. The clinical significance of the angle between first and second mandibular molar
and of the space between the first mandibular molar (MM1) and the anterior margin of mandibular ramus in MM2
impaction were also evaluated.
Material and Methods: In this retrospective study , from the dental records of 2,945 caucasian young orthodontics
patients, 40 subjects with MM2 impaction were included in a study group (SG) and compared with a control group
(CG) of 200 subjects without MM2 impactions. The crowding, the angle of inclination of MM2, the distance
between MM1 and mandibular ramus, the canine and molar relationships, and the lower centre line discrepancy
were measured. For the statistical analysis , descriptive statistics and t-Student for independent sample groups
were used.
Results: The prevalence of impacted MM2 was 1.36%. The independent-Samples t-Test between SG and CG
showed: the presence of crowding (P<=0.001), an higher angle values of MM2 inclination (P<=0.001) and a smaller
distance between MM1 and the anterior margin of mandibular ramus (P<=0.001) in the SG.
Conclusion: The impaction of MM2 is a relatively rare occurrence in orthodontic caucasian populations. The
crowding, a higher angle values of MM2 inclination and a reduced distance between MM1 and the anterior margin
of mandibular ramus, at the time of one third of MM2 root formation (T1), characterize MM2 impaction
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