Shannon E. Owens

Bio: Shannon E. Owens is an academic researcher from Raytheon. The author has contributed to research in topics: Osseointegration & Bracket. The author has an hindex of 4, co-authored 4 publications receiving 268 citations.

The effect of force, timing, and location on bone-to-implant contact of miniscrew implants.

Abstract: This study was conducted to evaluate the effect of timing and force of loading, as well as implant location, on bone-to-implant contact (BIC) of loaded and control miniscrew implants (MSI). Using seven skeletally mature male beagle dogs, 1-2 years of age, followed over a 110 day period, a randomized split-mouth design compared immediate versus delayed loading, 50 versus 25 g loading, and 25 g loads in the maxilla versus the mandible. Mobility was evaluated using a 0-3 point scale before the MSIs were prepared for histological analysis. Histomorphometric analyses were performed under light microscopy using Metamorph software on undecalcified sections. The percentage BIC was measured at three levels (coronal, middle, and apical) of the MSI. BIC was compared statistically using pairwise Wilcoxon signed-rank tests. Mobility was detected in three of the 56 (5.4 per cent) MSIs. The mobile implants were all unloaded controls and showed no BIC. All remaining stable MSIs showed some BIC. However, variation in BIC was large, ranging from 2.2 to 100 per cent. There were no significant (P > 0.05) differences in BIC associated with timing of force application, amount of force applied, or implant location. There was a tendency for less BIC at the coronal level, but the differences between levels were not statistically significant. Within the limits of this study, it is concluded that the timing and amount of force at loading and location of implant placement do not affect BIC. Moreover, it appears that only limited amounts of osseointegration are necessary to ensure implant stability.

A Prospective Study of the Risk Factors Associated with Failure of Mini-implants Used for Orthodontic Anchorage

Abstract: Purpose: The aim of this prospective clinical study was to assess the risk factors associated with failure of mini-implants used for orthodontic anchorage. Materials and Methods: A total of 140 miniimplants in 44 patients, including 48 miniplates and 92 freestanding miniscrews, were examined in the study. A variety of orthodontic loads were applied. The majority of implants were placed in the posterior maxilla (104/140), and the next most common location was the posterior mandible (34/140). Results: A cumulative survival rate of 89% (125/140) was found by Kaplan-Meier analysis. There was no significant difference in the survival rate between miniplates and freestanding miniscrews, but miniplates were used in more hazardous situations. The Cox proportional-hazards regression model identified anatomic location and peri-implant soft tissue character as 2 independent prognostic indicators. The estimated relative risk of implant failure in the posterior mandible was 1.101 (95% confidence interval, 0.942 to 1.301; P = .046). The risk ratio of failure for implants surrounded by nonkeratinized mucosa was 1.117 (95% confidence interval, 0.899 to 1.405; P = .026). Discussion and Conclusion: The results confirmed the effectiveness of orthodontic mini-implants, but in certain situations adjustment of the treatment plan or modifications in the technique of implant placement may lead to improved success rates. INT J ORAL MAXILLOFAC IMPLANTS 2004;19:100‐106

Assessment of mastication with implications for oral rehabilitation: a review

Abstract: Summary During chewing, food is reduced in size, while saliva moistens the food and binds the masticated food into a bolus that can be easily swallowed. Characteristics of the oral system, like number of teeth, bite force and salivary flow, will influence the masticatory process. Masticatory function of healthy persons has been studied extensively the last decades. These results were used as a comparison for outcomes of various patient groups. In this review, findings from literature on masticatory function for both healthy persons and patient groups are presented. Masticatory function of patients with compromised dentition appeared to be significantly reduced when compared with the function of healthy controls. The influence of oral rehabilitation, e.g. dental restorations, implant treatment and temporomandibular disorder treatment, on masticatory function will be discussed. For instance, implant treatment was shown to have a significant positive effect on both bite force and masticatory performance. Also, patient satisfaction with an implant-retained prosthesis was high in comparison with the situation before implant treatment. The article also reviews the neuromuscular control of chewing. The jaw muscle activity needed to break solid food is largely reflexly induced. Immediate muscle response is necessary to maintain a constant chewing rhythm under varying food resistance conditions. Finally, the influence of food characteristics on the masticatory process is discussed. Dry and hard products require more chewing cycles before swallowing than moist and soft foods. More time is needed to break the food and to add enough saliva to form a cohesive bolus suitable for swallowing.

The impact of malocclusion and its treatment on quality of life: a literature review

Abstract: Summary. Aim. The aim of this paper is to review the literature relating to the impact of malocclusion, and the treatment of malocclusion, on physical, social and psychological health (i.e. quality of life, QoL). Design. English-language papers, including cross-sectional studies, retrospective and prospective longitudinal studies, randomized controlled trials, and reviews and meta-analyses were reviewed to determine the impact of malocclusion and its treatment on QoL. Results. Malocclusion and its treatment can affect physical health in terms of pain (e.g. temporomandibular disorders, and dental and gingival trauma), speech and mastication. In terms of psychological health, malocclusion and its treatment is reported to affect self-concept. Socially, malocclusion and its treatment can affect perceived attractiveness by others, social acceptance and perceived intelligence. However, the evidence is conflicting owing to differences in study designs, population's studied and methods of assessment of psychical, social and psychological health. Conclusion. Much controversy exists about the impact of malocclusion and its treatment on QoL. There is a need for a more comprehensive and rigorous assessment of the impact of malocclusion and its treatment on QoL, employing standardized, valid and reliable data collection instruments.