Is maxillary diastema an appropriate site for implantation in rats?

Abstract

Background: Implantology or implant dentistry is growing fast during last four decades. Facing the growing demand of implant treatment, there are extreme challenges to clinicians and researchers. First is peri-implantitis with remarkable prevalence. Though investigators have revealed that the etiology of the peri-implant infection is similar to periodontitis, clinically there is no effective treatment. Second, implantation in patients with severe systemic conditions, i.e., severe diabetes, lupus, osteoporosis, organ transplant, and cancer with intensive radiotherapy and/or chemotherapy, is another challenge to implant treatment for lack of scientific research data. Animal models are crucial to help investigators reveal the mechanisms underlying these disorders. Murine models are used most commonly. Rats are the better subject in dental implant research, due to mice could not provide clinical compatible and macro-level measurable data for implant osseointegration and peri-implantitis in oral cavity for lacking enough cancellous bone to support an implant more than 1 mm in length. Objective: Our aim of this research is to find a clinical comparable rat dental implant model. Methods: Six male Sprague-Dawley rats with body weight more than 500 g were used in the experiment. Each rat received two implants. One implant was placed at maxillary diastema in each side. Seven weeks after the implantation, only one implant successfully osseointegrated without movement and inflammation. Implant success and failure rate is analyzed by using Clopper-Pearson's exact method at 95% confidence interval. Results: The present data indicate that the true success rate of implantation in maxillary natural diastema in rat is less than 38.4% at a confident level of 95%. Meanwhile, Micro-CT indicates maxillary first molar position will be a promising site for implantation. Conclusion: Maxillary nature diastema may not be an appropriate site for implantation research for its low successful rate, but maxillary first molar position could be a candidate for implantation research. Further researches are required to illustrate the details.

Cellular and Molecular Dynamics during Early Oral Osseointegration: A Comprehensive Characterization in the Lewis Rat

“…82,85,86 Finally, both models have a large variety of implant dimensions ranging from 0.67 to 1.7 mm in diameter and 2.0−4.5 mm in length. 73,76,82,84,88 One could argue that these variations in implantation procedures, implant size, and bone quality at different locations may reflect what happens in the clinic. However, these in vivo models strive to provide an accurate simulation of the best-case wound-healing scenario.…”

“…A number of studies have employed two particular types of maxilla implantation in the rodent: those which involve extraction of one or more of the first molars before placement of the implant (extraction models) − or direct implantation into the maxillary diastema without tooth extraction (nonextraction models). − Further examination of either of these models will uncover a large variety in methodology. In extraction models, the placement of the implant is reported to be either immediately following tooth extraction − ,, or up to 30 days after. ,− , Placement is also inconsistent, in bed of the first molar, ,− ,, anywhere between the first and second molar, or the socket where the mesial root of the first molar is located before extraction. , In nonextraction models, implantation into the maxillary diastema can occur anywhere anterior to the first molar and posterior of the incisor roots. ,, Finally, both models have a large variety of implant dimensions ranging from 0.67 to 1.7 mm in diameter and 2.0–4.5 mm in length. ,,,, One could argue that these variations in implantation procedures, implant size, and bone quality at different locations may reflect what happens in the clinic. However, these in vivo models strive to provide an accurate simulation of the best-case wound-healing scenario.…”

Pre-Clinical Models in Implant Dentistry: Past, Present, Future

“…Another possibility is to use the maxillary diastema, mesial to the molars. A recent study has successfully shown a model of peri-implantitis in this area [ 378 ], but the validity of this model has yet to be demonstrated [ 379 ]. The maxilla is also used for classic implant surface comparisons [ 376 ], mechanical testing [ 380 ], and analysis of pathophysiological processes [ 381 , 382 , 383 , 384 , 385 ].…”