Evidence-based dentistry: Reality and dilemmas

The concept of evidence-based practice [EBP] relies on rendering treatment, the effectiveness is solidly demonstrated by rigorous research, not just empirical experience. The aim of this paper is to review the foudation of EBP and the reality of its application. Evidence is commonly ordered up in a "hierarchy" from expert opinion to case report, case series, case-control study, cohort study, randomized controlled trial, and systematic review/meta-analysis. We stratify this hierarchy into 3 categories ascending from perspective, to investigation then synthesis. Depending on the type and feasibility of research, the higher levels of evidence do not negate the value of lower strata. The application of evidence is illustrated in two representative areas of dentistry: timing of early orthodontic treatment and immediate loading of osseointegrated implants. The clinician faces dilemmas in the need to ground treatment into unquestionable basis and the difficulty of relating this basis to the individual treatment. Reasons for this dichotomy include the scale of variation around mean results delivered by the most sophisticated research and the potential for new more encompassing research to deviate from prior findings. While research sets central tendencies, individual variation favors interpretation of the evidence. In the face of viewpoints on EBP ranging from support to rejection, the clinician should not indict a needed process, but rather use judgment to apply the average response shown in investigations to the individual circumstances of patients

Individual appraisal of facial soft and hard tissues with the mesh diagram

The lateral cephalometric mesh diagram analysis presents advantages not readily available in conventional cephalometric methods. The face is oriented on the patient's natural head position, which provides comparability between cephalometric findings and the clinical facial examination. The patient's profile is not directly compared with the population norm but with an "individualized norm" derived from the application of the population norm to a grid scaled on the patient's facial shape namely, the upper face height [N-ANS] and facial depth [N-S]. Each landmark is assessed by its proportionate location in the mesh diagram grids. Thus, facial form is evaluated in one single display easily interpretable without computation of linear and angular measurements. These principles are illustrated for diagnosis of malocclusions and treatment with a combination of orthodontics and orthognathic surgery. The discrepancies between hard and soft tissues are readily ascertained and measured through the mesh display, and allow the formulation of conclusions on treatment and outcome. The mesh diagram is a flexible cephalometric analysis that should be incorporated in the routine dentofacial diagnosis and treatment planning

Root resorption during orthodontic tooth movement: a literature review

External root resorption [ERR] of permanent teeth is an unpredictable consequence of orthodontic treatment, usually diagnosed on periapical radiographs. The etiological and biochemical mechanisms are still unclear. Theories include excessive force that leads to the development of an avascular area referred to as hyalinized, resulting, through a cascade of cellular events, in increased cementoclast-osteoclast activity. Yet, risk .factors are incriminated that may be classified in two major categories: constitutional factors [gender, chronologic and dental ages, genetics, individual susceptibility, systemic factors, tooth structure, alveoloar hone density, specific tooth vulnerability to root resorption]; physiologic and environmental factors [nutrition, habits, occlusal trauma, endodontic treatment, trauma prior to orthodontic treatment, mechanical pressure such as types of orthodontic movement, appliances, and forces, duration of orthodontic treatment, repeated orthodontic treatment]. When resorption is detected, treatment objectives should be modified to maintain appropriate crown-to-root ratio and periodontal health, while light forces are used and root length monitored