Prosthetic rehabilitation of maxillary lateral incisors agenesis using dental mini-implants: a multicenter 10-year follow-up

Implant-supported crowns on maxillary laterals and canines-a long-term follow-up of aesthetics and function

OBJECTIVES

To assess the long-term aesthetic and functional aspects of implant-supported crowns in lateral (ISC-L) and canine positions (ISC-C).

MATERIALS AND METHODS

Thirty-two patients (14 males, 18 females, mean age: 23.1, SD:2.0) with an ISC-L or ISC-C participated in this prospective cohort study at baseline (T0) and in the long-term follow-up (T1, mean years: 11.1, SD: 1.0). Twenty-four patients (11 males, 13 females) participated in T1. Patient-reported outcomes (PROM) were rated using surveys with questions related to aesthetics and function. The colour of the implant crown and the buccal gingiva, the appearance of the papilla, periodontal health and temporomandibular disorder (TMD) outcomes were assessed in a clinical examination. The Mann-Whitney, Chi-square and Signed Rank tests were performed.

RESULTS

Patients with an ISC-L and ISC-C were equally satisfied with the crown shape and colour at T0 and T1. No differences in TMD outcomes were reported by the patients and no clinical signs of TMD were observed. At T1, ISC-C had more bleeding on probing and a three mm greater pocket depth than ISC-L (p = 0.03, p = 0.01, respectively). At T0, operators graded the crown colour of ISC-L as being too dark (35%) and ISC-C as being too light (40%). At T1, no difference was seen between the two groups regarding crown colour, gingiva colour and the papilla (p = 0.2749, p = 0.2099, p = 0.8053, respectively).

CONCLUSIONS

The PROM and clinical examination show that ISC-L and ISC-C are equivalent with regard to aesthetics and function in the long term.

CLINICAL RELEVANCE

Although ISC-L and ISC-C are aesthetically and functionally comparable in the long term, ISC-Cs are more likely to impact periodontal health.

Interdisciplinary Management of Bilateral Congenital Lateral Incisor Agenesis

Management of lateral incisor agenesis is a real challenge and needs a strong collaboration between surgical, aesthetic, and orthodontic dentistry. This case report managed upper lateral incisor agenesis with an orthodontic treatment leading to open spaces and placement of cuspids in lateral incisor area to avoid implant placement in maxillary anterior region. Temporary rehabilitation phase, using resin injected tray and removable partial denture, has been placed to maintain mesiodistal dimensions and restore aesthetic during pre-implant analysis and osseointegration. Once osseointegration was fully obtained, keratinized tissue augmentation has been obtained using connective tissue graft. Then, temporary implant fixed crowns allowed soft tissue modeling during interim rehabilitation. Finally, screw-retained permanent crowns were placed to fully restore aesthetic and function. This case goal was to optimize final results and reach patient complete satisfaction using orthodontic treatment combined with implant rehabilitation, and coupled with interdisciplinary management and well-time sequencing treatment.

A digital workflow for pair matching of maxillary anterior teeth using a 3D segmentation technique for esthetic implant restorations

We investigated a state-of-the-art algorithm for 3D reconstruction with a pair-matching technique, which enabled the fabrication of individualized implant restorations in the esthetic zone. This method compared 3D mirror images of crowns and emergence profiles between symmetric tooth pairs in the anterior maxilla using digital slicewise DICOM segmentation and the superimposition of STL data. With the outline extraction of each segment provided by 100 patients, the Hausdorff distance (HD) between two point sets was calculated to identify the similarity of the sets. By using HD thresholds as a pair matching criterion, the true positive rates of crowns were 100, 98, and 98%, while the false negative rates were 0, 2, and 2% for central incisors, lateral incisors, and canines, respectively, indicating high pair matching accuracy (> 99%) and sensitivity (> 98%). The true positive rates of emergence profiles were 99, 100, and 98%, while the false negative rates were 1, 0, and 2% for central incisors, lateral incisors, and canines, respectively, indicating high pair matching accuracy (> 99%) and sensitivity (> 98%). Therefore, digitally flipped contours of crown and emergence profiles can be successfully transferred for implant reconstruction in the maxillary anterior region to optimize esthetics and function.

Bone Dimensional Change Following Immediate Implant Placement in Posterior Teeth with CBCT: A 6-Month Prospective Clinical Study

This prospective clinical study aimed to evaluate the peri-implant hard tissue dimensional change at 6 months of immediate implant placement with bone graft materials in the posterior area using cone-beam computed tomography (CBCT). Twelve dental implants were placed concurrently following tooth extraction in the posterior area and filled with xenograft particles. The CBCT images were taken immediately after surgical procedures and then at 6 months follow-up. To evaluate the hard tissue changes, the vertical and horizontal bone thickness were analyzed and measured using ImageJ software. Paired t-test or Wilcoxon match-pair signed-rank test was done to analyze the changes of hard tissue values at the same level between immediately and 6 months following immediate implant placement. Independent t-test or Mann-Whitney U test was used to analyze the dimensional change in the vertical and horizontal direction in buccal and lingual aspects. The level of significance was set at p value = 0.05. All implants were successfully osseointegrated. At 6 months follow-up, the vertical bone change at the buccal aspect was -0.69 mm and at the lingual aspect -0.39 mm. For horizontal bone thickness, the bone dimensional changes at 0, 1, 5, and 9 mm levels from the implant platform were -0.62 mm, -0.70 mm, -0.24 mm, and -0.22 mm, respectively. A significant bone reduction was observed in all measurement levels during the 6 months after implant placement (p value < 0.05). It was noted that even with bone grafting, a decrease in bone thickness was seen following the immediate implant placement. Therefore, this technique can be an alternative method to place the implant in the posterior area.