Alveolar ridge reduction after tooth extraction in adolescents: An animal study

Abstract

Objective The mechanism for tooth extraction induced residual alveolar ridge reduction (RRR) during adolescence is poorly understood. This study investigated the alveolar bone morphology, growth, resorption and functional loading at normal and extraction sites using an adolescent pig model. Design Sixteen 3-month-old pigs were divided into two groups – immediate post-extraction (IE) and 6-week post-extraction (SE). The IE group received an extraction of one deciduous mandibular molar, immediately followed by a final experiment to record masseter muscle EMGs and strains from the buccal surface of the extraction and contralateral non-extraction sites during function (mastication). The SE group was given the same tooth extraction, then kept for 6 weeks before the same final functional recording as the IE group. Both groups also received baseline (pre-extraction) EMGs and fluorescent vital stains 10 and 3 days before the final functional recording. Immediately after the final functional recording, animals were euthanized and alveolar bone specimens from extraction and contralateral non-extraction sites were collected and used to analyze alveolar bone morphology, apposition and resorption based on fluorescent and hematoxylin and eosin stained histological sections. Results At control sites (IE-extraction, IE-non-extraction and SE-non-extraction), the alveolar ridges grew gingivally and buccally. Bone formation characterized the buccal surface and lingual bundle bone, whereas resorption characterized the lingual surface and buccal bundle bone. The SE-extraction sites showed three major alterations: convergence of the buccal and lingual gingival crests, loss of apposition on the lingual bundle bone, and decelerated growth at the entire buccal surface. These alterations likely resulted from redirected crestal growth as part of the socket healing process, loss of tongue pressure to the lingual side of the teeth which normally provides mechanical stimulation for dental arch expansion, and masticatory underloading during the initial post-extraction period, respectively. Conclusions These data indicate that the initial phase of RRR in adolescents is a product of modified growth, not resorption, possibly because of decreased mechanical stimulation at the extraction site.

Standardized Rat Model Testing Effects of Inflammation and Grafting on Extraction Healing

“…Dentists involved with implant dentistry are interested in preservation of alveolar bone after extraction due to well‐documented changes in bone quality and quantity at the site 1 , 2 . Numerous techniques and interventions have been proposed to reduce negative effects of postextraction conformational changes 16 , 17 .…”

“…Extraction of teeth routinely involves creation of a bony defect and associated bony and soft tissue changes. Alveolar bone is a tooth‐dependent structure, and extraction of teeth results in compensatory fill of the extraction site in addition to well‐documented reduction in alveolar ridge width and height 1 , 2 . All of this occurs in an environment laden with bacteria capable of inducing variable amounts of inflammation.…”

“…Dentistry is heavily invested in research to preserve and enhance the alveolar bone and associated periodontal structures, especially in achieving a stable and esthetic result after compensatory tooth movement, prosthetic replacement, or implant placement. Although postextraction changes in alveolar bone are well described, 1 , 2 cost‐effective models to dissect impact of inflammation and grafting or pharmacologic interventions are lacking. Refining a model to better define effect of inflammation on the healing process after extraction will strengthen the foundation of knowledge and provide a basis for future studies of modifications of the process using pharmacologic interventions.…”

Growth characteristics underlying the lack of a chin in pigs: a histomorphometric study

“…Cadaver mandibles were obtained from two age groups of juvenile (4‐month‐old and 6‐month‐old) female domestic pigs ( Sus scrofa ), which were used in a previous tooth extraction study and a distraction osteogenesis study, respectively . All live animal procedures were approved by the Institutional Animal Care and Use Committee at The Ohio State University.…”

Dental Implantation of Atrophic Jaws Reconstructed with Iliac Bone Graft Crest - Outcome of Seven Cases

“…Bone resorption is attributed to the diminished functional loading at the edentulous ridges even though this theory is not completely proven [5]. General and local factors affect the resorption process including osteoporosis, endocrine disorders, nutritional deficiencies, local vascular changes, diseases of the soft tissue of the mouth, jaw surgeries, traumatic tooth removals, etc.…”