Liddelow G, Klineberg I: Patient-related risk factors for implant ther-

apy. A critique of pertinent literature. Austral Dent J 56:417-426,2011

Fig 1.—Achievement of radiographic bone density data using HLImagearea; RNFB, cervical, middle, and apical thirds of sockets corresponding tais de Melo W, Carneiro-Avelino C: Comparative radiographic evaluationplasma after impacted mandibular third molar surgery. J Oral Maxillofa

Reprints available from I Klineberg, Westmead Hosp, Faculty of Den-tistry, The Univ of Sydney, Level 3, Profial Unit, Westmead NSW2145; e-mail: ivenk@mail.usyd.edu.au

Oral SurgeryPlatelet-rich plasma for bone healing

Background.—Defects in facial skeletal bone may sig-nificantly alter proper prosthetic and functional rehabilita-tion of the stomatognathic system. To accelerate thegrowth of new bone tissue, autologous platelet-rich plasma(PRP) has been used. It accelerates healing through concen-trations of growth factors, including transforming growthfactor-b, vascular endothelial growth factor, three isomersof platelet-derived growth factor, and endothelial growthfactor. These growth factors accelerate chemotaxis, mito-genesis, angiogenesis, and the synthesis of collagen matrixand favor tissue repair when applied to bone wounds. Re-cently, studies have questioned the efficacy of PRP to accel-erate bone healing, so a study of radiographic bone healingusing autologous PRP after tooth extraction was conducted.

Methods.—Fifteen volunteers, aged 18 to 22 years, un-derwent 30 extractions of bilateral impacted mandibular

third molars. The socket on one side was treated with autol-ogous PRP, whereas the socket on the opposite side wasfilled with blood clot (control group). Millimeter periapicalradiographs were taken after 7 days and 1, 2, 3, and 6months postoperatively. HLImage 97 software was used toquantify radiographic bone density three times (Fig 1).

Results.—Postoperative pain, edema, and limitedmouth opening were well controlled. Some patients spon-taneously reported mildly altered facial volume on the sideof the PRP treatment. No excessive bleeding developed.

The mean radiographic bone density for the PRP groupwas 79.24%, whereas that in the control group was 70.83%.PRP thus facilitated a significant improvement in bone heal-ing in the tooth sockets after mandibular third molarextractions.

97 software. Abbreviations: BA, background area; NBA, natural boneo regions of newly formed bone. (Courtesy of C�elio-Mariano R, Mor-of alveolar bone healing associated with autologous platelet-rich

c Surg 70:19-24, 2012.)

Volume 58 � Issue 1 � 2013 17

There were significant differences between the PRPgroup and controls after 1, 2, and 3 months. However, atthe 7-day and 6-month evaluations, there were no statisti-cally significant differences between the two groups. ThePRP group did have higher mean radiographic bone densitythan the control group even at the 7-day and 6-monthassessments.

Overall, the PRP group had faster bone formation thanthe control group. Men in the control group had significantalveolar bone formation compared with women in thatgroup. Men in the PRP group had higher mean radiographicbone density than women, but the difference did not reachstatistical significance.

Discussion.—Applying autologous PRP to surgicalbone wounds after tooth extraction was able to acceleratebone healing, particularly in men. It is important to notethat this study used sodium citrate as an anticoagulantand calcium chloride as a coagulant because other sub-stances can damage the PRP platelets and allow growth fac-tors to be released too quickly and to be lost in theinterstitial tissues. Adequate centrifugation forces are alsoneeded because greater force levels are associated withgrowth factor release during PRP preparation. Thus, thetechnique used to prepare PRP is highly sensitive to

18 Dental Abstracts

variation and requires attention to detail to achieve thebest result.

Clinical Significance.—Autologous PRP is in-expensive and widely available for use in woundhealing applications. This study indicates that itincreasesbothhardandsoft tissuehealingpoten-tial. It is interesting that it was more advanta-geous for men than for women. PRP is a validway to induce and accelerate bone healingwhen used for periodontal defects at the distalroot of themandibular secondmolar after the ex-traction of impacted mandibular third molars.

C�elio-Mariano R, Morais de Melo W, Carneiro-Avelino C: Compara-tive radiographic evaluation of alveolar bone healing associatedwith autologous platelet-rich plasma after impacted mandibularthird molar surgery. J Oral Maxillofac Surg 70:19-24, 2012

Reprints available from R C�elio-Mariano, Dept of Clinic and Surgery,Federal Univ of Alfenas, Rua Manoel Jos�e de Almeida, 52H, JardimColin�as Parque, 37130-000 Alfenas, Minas Gerais, Brazil; e-mail:mariano.int@efoa.br

Orthognathic surgery

Background.—Orthognathic surgery is performed tocorrect discrepancies that are skeletal in origin and to im-prove speech, aesthetics, and function. For growing pa-tients, early treatment does not always eliminate the needfor future surgery. Orthognathic problems are best handledthrough a multidisciplinary approach involving both an or-thodontist and an orthognathic surgeon. The patient is theprimary member of the team and should be involved in alldiscussions, noting his or her expectations and concerns. Is-sues that often concern a patient include the final outcomeof treatment, cost issues, duration of hospitalization, andtreatment-associated complications. Factors that influencethe type and frequency of complications include surgicalsite, duration of surgery, surgical approach, wound contam-ination, and expertise of the surgeon. Type of surgery,whether advancement or setback, and nature of the surgicalcuts must also be considered and discussed with the pa-tient. Data were collected to provide a nationally represen-tative estimate of the number and type of differentorthognathic procedures done in hospitalized patients inthe United States.

Methods.—The data were collected from the Nation-wide Inpatient Sample for 2008 and included all hospitaliza-tions for orthognathic surgery. The procedures wereidentified using the procedure codes from the InternationalClassification of Diseases, Ninth Revision, Clinical Modifica-tion. Outcomes were noted, and estimates were projectedto national levels.

Results.—For the 10,345 hospitalizations for orthog-nathic surgery in the United States in 2008, the averageage of the patients was 26.7 years. Over half (56.2%) ofthe patients were female, and most of the procedureswere elective. Race data were missing for 3159 hospitalizedpatients, but the rest were white (71.9%), black (4.9%), His-panic (12.6%), Asian/Pacific Islander (5.6%), Native Ameri-can (0.4%), and other (4.6%). The primary payers wereprivate insurance plans in 77.3% of the cases.

A single procedure was done in 53.3% of the hospitaliza-tions, two in 36.8%, three in 9.2%, and four in 0.7%. The pri-mary procedures done were segmental osteoplasty of the