A wide mesio‐distal gap in sites of congenitally missing maxillary lateral incisors is related to a thin alveolar ridge

Abstract

In patients congenitally missing I2, an increased mesio-distal gap width correlates significantly with reduced edentulous AR dimensions. A mesio-distal gap of >6 mm was associated with thin bucco-palatal alveolar ridges, precluding straightforward implant placement in 60-80% of the cases.

Alveolar bone resorption after primary tooth loss has a negative impact on straightforward implant installation in patients with agenesis of the lower second premolar

“…On the other hand, a geometric morphometric evaluation of the whole mandibular cross‐section in the current group of patients (Bertl, Bertl et al., ) revealed that cross‐sectional mandibular size and shape differed significantly between patients with and without P2 agenesis, and that the differences extended beyond a localized morphological change at the agenesis sites, and involved the neighboring teeth and body of the mandible. Nevertheless, the average mesio‐distal crown dimension of the primary second molar is about 10 mm (Harris & Lease, ); the fact that in the present material in the AWO group straightforward placement of an implant, which was about 1 mm larger in Ø comparing to what was simulated in the above‐mentioned study (Bertl, Grotthoff et al., ), was possible in 50% of the cases and may indicate that the dimensions of the alveolar bone in the posterior aspects of the jaws are relatively less influenced by agenesis comparing to the anterior aspects. However, the observed differences regarding the possibility for straightforward implant placement in anterior and posterior jaw aspects, as observed in the two studies, may simply be due to differences in the average bucco‐oral dimensions of the anterior and posterior jaw aspects (i.e., thinner vs. thicker, respectively); in other words, despite similar relative influence by agenesis in anterior and posterior jaw aspects, the remaining bucco‐oral width of the alveolar ridge in the posterior aspects of the jaw was enough for straightforward implant placement.…”

“…On the other hand, a geometric morphometric evaluation of the whole mandibular cross-section in the current group of patients revealed that cross-sectional mandibular size and shape differed significantly between patients with and without P2 agenesis, and that the differences extended beyond a localized morphological change at the agenesis sites, and involved the neighboring teeth and body of the mandible. Nevertheless, the average mesio-distal crown dimension of the primary second molar is about 10 mm (Harris & Lease, 2005); the fact that in the present material in the AWO group straightforward placement of an implant, which was about 1 mm larger in Ø comparing to what was simulated in the above-mentioned study (Bertl, Grotthoff et al, 2016), conflict of interest, and no external funding was obtained for performing the present study.…”

“…In that study, a mesio-distal gap >6 mm prohibited straightforward placement of an implant with an appropriate diameter (e.g., 3.5 mm in Ø) in 80% of the cases (Bertl, Grotthoff et al, 2016).…”

“…The craniofacial morphology differs in various aspects between agenesis and non‐agenesis patients (Gungor & Turkkahraman, ; Kreczi, Proff, Reicheneder, & Faltermeier, ), and in a previous similar analysis on tomographic images of patients with agenesis of the lateral maxillary incisor, the alveolar ridge in sites without the primary tooth in situ was significantly narrower bucco‐palatally compared to non‐agenesis patients, irrespective whether the permanent tooth was in situ or not (Bertl, Grotthoff et al., ). Further, a significant negative correlation of the mesio‐distal gap width with the bucco‐palatal width of the alveolar ridge was observed, that is, the wider the mesio‐distal gap, the thinner was the alveolar ridge bucco‐palatally especially at its coronal aspect.…”

“…Further, a significant negative correlation of the mesio‐distal gap width with the bucco‐palatal width of the alveolar ridge was observed, that is, the wider the mesio‐distal gap, the thinner was the alveolar ridge bucco‐palatally especially at its coronal aspect. In that study, a mesio‐distal gap >6 mm prohibited straightforward placement of an implant with an appropriate diameter (e.g., 3.5 mm in Ø) in 80% of the cases (Bertl, Grotthoff et al., ). In the current study, no evaluation of the possible impact of the mesio‐distal gap on the bucco‐oral dimension was performed.…”