Influence of Mouth Breathing on Outcome of Scaling and Root Planing in Chronic Periodontitis

INTRODUCTION

Mouth breathing is perceived to be responsible for persistant marginal gingivitis. The most common region to be affected by gingivitis in mouth breathers is maxillary anterior region. Other areas are affected in following decreasing order: maxillary posterior areas, mandibular anterior region and mandibular posterior region. Various reasons are considered to be responsible for gingival inflammation in mouth breathers. Possible factors responsible for gingival inflammation may be continuous loss of saliva over marginal tissues leading to increased plaque scores or qualitative change in plaque in terms of incorporation of more virulent strains of bacteria in plaque.

Mouth breathing, lip seal, upper lip coverage are related. In one study, mouth breathing along with incompetent lip seal and decreased upper lip coverage were associated with gingivitis. In other study plaque was thought to be a contributing factor for gingivitis in patients with decreased upper lip coverage. One study showed lack of lip seal due to increased overjet to be responsible for increased gingival inflammation. Kolawole KA et al in their study found that lip incompetence was associated with increased plaque scores. It may be due to lack of normal cleansing action of saliva. No association between mouth breathing and gingivitis prevalence had been reported in the study by Sutcliffe. However mouth breathing slightly increased severity of gingivitis.

Saliva performs very important functions including lubrication of oral tissues, antimicrobial action, regulation of pH, elimination of food bolus and facilitating in removal of carbon. Salivary flow provides mechanical cleansing of residues present in mouth such as non adherent bacteria, cellular and food debris. Lack of salivary flushing action results in accumulation of food debris and dental plaque thus promoting an acidogenic and aciduric oral bacteria responsible for dental caries.

Xerostomia /dry mouth is responsible for increase in gingival inflammation and also affects periodontal conditions with increased probing depth, plaque index. In one study, young adults with self reporting of xerostomia had increased sites with bleeding on probing and increased plaque scores. Proliferative activity of oral gingival epithelium is decreased in inflamed gingiva of patients with xerostomia. In one study, healing in gingivectomy wound was delayed in sialadenectomized rats.