The Use of CAD/CAM Technology in Mandibular Canine Disimpaction: A Case Report.

This case report of an 11-year-old subject shows the digital workflow for the management of an impacted mandibular canine using Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) technology along with Temporary Anchorage Devices (TADs). The miniscrew insertion site was planned using software, and a surgical guide was digitally designed and 3D printed. Orthodontic traction was performed using a 3D-designed and -printed device. In a single sitting, the miniscrew was inserted and the disimpaction device was also delivered. The primary objective of recovery and the repositioning of the impacted mandibular canine in the axis with its eruptive path was achieved. The space available and the subject's early stage of mixed dentition was considered favourable to a spontaneous eruption. This case report shows how CAD/CAM digital technology, combined with 3D printing, enables the creation of a surgical guide to position the miniscrew and the customized devices used for mandibular canine disimpaction. CAD/CAM surgical guides can help clinicians to position TADs with more accuracy and predictability, ensuring high quality bone support offering primary stability. Although orthodontic traction is the most complex therapeutic choice to implement, with the aid of CAD/CAM technology it is possible to proceed with accurate and minimally invasive orthodontic traction in order to recover a mandibular canine.

Computer-guided miniscrew insertion in the paramedian and parapalatal area of the palatal vault: low failure rate and no learning curve required to obtain predictable results?

AIM: To evaluate the failure rate of palatal computer-guided miniscrews, placed in paramedian and parapalatal regions for orthodontic purposes. In addition, to investigate the presence of a learning curve using computer guided miniscrew insertion, and to evaluate the peri-implant soft tissues response at 2-, 6- and 12- month follow-ups. MATERIALS AND METHODS: 202 palatal computer-guided miniscrews were inserted in 78 subjects for orthodontic purposes. A surgical guide was designed after planning the appropriate insertion sites on three-dimensional images created by the fusion of cone-beam computed tomography (CBCT) and digital dental model images. The devices were disassembled monthly to perform the percussion test and to evaluate the mobility of each miniscrew. To determine the presence of a learning curve, the time of miniscrew failures and the number of surgeries were evaluated. Bleeding on probing (BOP) and probing pocket depth (PPD) were recorded for each miniscrew, at 2- (T0), 6- (T1), and 12-month follow ups (T2). RESULTS: An immediate failure rate of 4.95%, due to lack of primary stability immediately following miniscrew insertion, was recorded, with statistically significant higher failure rate of parapalatal miniscrews (P= 0.00). Miniscrew failure occurred at random time, with an absence of a learning curve. The BOP (mean: 3.13%) and PPD (mean: 1.68mm) measurements remained stable over time. CONCLUSIONS: Computer-guided miniscrew insertion in the palatal vault showed a low failure rate without a determined learning curve to obtain predictable results and with long-term stability of peri-implant soft tissues indexes.

Smile esthetic: comparison of perception amongst orthodontists, dental students, orthodontic patients and surgical orthodontic patients

Most patients require orthodontic treatment to improve the esthetics of their smile. Orthodontists must consider how some parameters of mini-esthetics can influence the patient's esthetic perception. Methods: A photograph of the smile of a young female was taken and some modifications were made to the buccal corridor, gingival exposure, smile arc and midline position to assess the influence of these variables on smile attractiveness. Two hundred examiners were selected from four groups: orthodontists (O), dental students (DS), orthodontic patients (OP) and surgical-orthodontic patients (SOP). Each examiner was asked to complete the questionnaire with an approval rating from 1 to 10. Significant level was set at P ≤ 0.05. Results: Only orthodontists considered buccal corridors of 4mm and midline deviation of 1mm as non-esthetic; all other examiners considered gingival exposures ≥3 mm and midline angulation as non-esthetic. All examiners assigned higher satisfaction values to the photo with the concordant smile arc and defined as non-esthetic the covered smile and the reverse smile arc. Patients perceived as non-esthetic only midline deviations of 4mm. The surgical orthodontic patients assigned lower values to the photos and showed greater attention to evaluating the esthetics of the smile than the orthodontic patients. Conclusion: Smile arc, gingival exposure and midline angulation influence smile esthetics; the role of buccal corridors and midline deviation is dependent on the type of examiner

Comparing Distal-Jet with Dental Anchorage to Distal-Jet with Skeletal Anchorage: A Prospective Parallel Cohort Study.

The use of traditional intra-oral devices in maxillary molar distalization is not without undesirable consequences. The aim of the present study was to compare the miniscrew-supported distal-jet appliance to a traditional distal-jet appliance by evaluating the amount of upper first molar distalization and the dentoalveolar side effects. Data of 600 subjects visited at the orthodontic unit of Sapienza University of Rom were analyzed. Only 46 patients met the inclusion criteria and were selected and treated. Subjects were assigned randomly to receive treatment either with miniscrew-supported distal-jet appliance (Group A) or with a traditional distal-jet appliance (Group B). In Group A, miniscrews were inserted using a computer-guided surgical guide. The amount of upper first molar distalization and the dentoalveolar side effects were assessed both on the digital casts and on the lateral cephalometric radiograph at the end of the distalization phase. A descriptive statistical analysis that included the mean values and the standard deviation was conducted to evaluate the molar distalization and the dentoalveolar effects in two groups. Intergroup differences were determined using the Student's t-test. The significance was set at p ≤ 0.05. In Group A, greater maxillary first molar distalization and a spontaneous distalization of the first premolars and a palatal inclination of central incisors were observed. By contrast, in Group B, the first premolars tipped mesially and a proclination of the maxillary central incisors was observed. In both groups, the transverse widths of the dental arch increased while a greater tendency of first premolar extrusion and of maxillary first molar rotation was observed in Group B. The skeletal anchorage device achieved greater first molar distalization and did not cause dento-alveolar side effects.

Comparision of profile macro-estethic perception among orthodontists, dentistry students, orthodontic patients and surgical orthodontic patients.

BACKGROUND: The patient's needs should guide the orthodontist in choosing the most appropriate therapy. The purpose of the present survey was to compare the esthetic perception of the facial profile by orthodontists (O), dentistry students (DS), orthodontic patients (OP) and surgical-orthodontic patients (SOP) and to evaluate the influence of gender, age and level of study. MATERIAL AND METHODS: A facial profile photograph of a young female was taken and twelve modified images were made, altering the position of the jaws in protrusion and in retrusion. Two hundred caucasian examiners, divided into four groups (O, DS, OP, SOP), were selected. Each examiner was asked to complete the questionnaire with an approval rating from 1 to 10. An ordinary least square OLS model was applied. Significant levels were set at P ≤ 0.05. RESULTS: All examiners considered a straight profile or a slight retrusion of the maxilla as the most attractive profile. Slight discrepancies (up to 2 mm) in jaw protrusion were barely perceived by patients. Mandibular retrusion (2 and 4 mm) was one of the least appreciated condition by all examiners. Surgical-orthodontic patients assigned lower ratings compared to orthodontic patients. Female subjects assigned lower ratings than males. Patients with secondary school education assigned higher statistically significant values compared to other levels of study. The lowest values were attributed by the sample of age > = 17 years. CONCLUSIONS: The choice of the most appropriate therapy is based not only on a correct diagnosis, but on the evaluation of esthetic and psychological aspects. Key words:Estethic, profile, orthodontic, surgical orthodontic patients.

Uprighting Impacted Mandibular Second Molar Using a Skeletal Anchorage: A Case Report.

The aim of this case report is to present an innovative combined orthodontic-surgical technique to disimpact mandibular second molar (MM2) using an orthodontic miniscrew and an elastic chain. The impact on the Oral health-related quality of life (OHRQoL) was also evaluated. Using the present techinique, it is possible to expose the impacted tooth, insert a self-drilling miniscrew in the retromolar area, and remove the bud of third mandibular molar. At the same time the orthodontic force is applied with the use of an elastomeric chain that connects the head of miniscrew and vestibular and oral buttons bonded on MM2. A close traction is performed for the whole treatment time without the reactivation of the elastic force. The use of skeletal anchorage allowed the disimpaction of impacted MM2 in a short treatment time (about three months) avoiding the typical biomechanical side effects of traditional orthodontic appliance and increasing the effectiveness of the treatment. Further studies are necessary to evaluate the real advantages and disadvantages of this combined orthodontic-surgical approach.